Episode 208: Bad News, Good News

Chris Dall: Hello and welcome to the Osterholm update, a podcast about infectious diseases and public health featuring Dr. Michael Osterholm. Dr. Osterholm is an internationally recognized medical detective and director of the center for Infectious Disease Research and Policy, or CIDRAP, at the University of Minnesota. In this podcast, Dr. Osterholm draws on over 50 years of experience in infectious disease epidemiology to provide straight talk on the latest infectious disease outbreaks, counter misinformation and disinformation about vaccines, and distill the complex and ever evolving public health threats facing our world. I'm Chris Dall, reporter for CIDRAP news, and I'm your host for these conversations. Welcome back everyone to another episode of the Osterholm update podcast. From the moment it received emergency use authorization from the Food and Drug Administration, Paxlovid has been one of the primary antiviral medications for adults with COVID-19 who are at risk for hospitalization or death. Some of you might remember the "If it's COVID, Paxlovid" tagline created by drugmaker Pfizer in its advertisements for the drug. But the results of two randomized clinical trials published recently in the New England Journal of Medicine found that Paxlovid failed to reduce hospitalizations or deaths in adults with risk factors for severe COVID-19 outcomes. On its face, that seems like bad news. But as emergency physician researcher and writer doctor Jeremy Faust noted recently in his Inside Medicine Substack column, it also contains some good news because there were no deaths from any cause in the study.

Chris Dall: And that tells us something about where we are with COVID. "Yes. The fact that two major studies conducted in 2022 to 2024 failed to show this benefit for Paxlovid is cause for celebration," Faust wrote. COVID-19 is no longer the massive mortality threat it once was. It's nowhere near the hospitalization threat, either. The results of these two Paxlovid trials and what they tell us about COVID-19, are among the topics we'll be addressing on this May 7th episode of the Osterholm update, episode number 208. We'll also discuss a CDC study on COVID-19 vaccines that's been blocked by the acting CDC director. Examine a survey that reveals the impact of changes to CDC messaging on vaccines and autism. Explore the US Defense Secretary's decision to no longer require flu shots for US military members. Provide an update on U.S. measles outbreaks and respiratory virus activity. Bring you up to speed on the hantavirus outbreak on a Dutch cruise ship, and review the findings of CIDRAP analysis of HPV vaccines. And of course, we'll have the latest installment of This Week in Public Health history. There is a lot to get to in this episode. But before we get started, as always, we will begin with Dr. Osterholm opening comments and dedication.

Dr. Michael Osterholm: Thanks, Chris, and welcome to the podcast family. It's good to have you all back again. As Chris noted, we have a lot to cover today. I want to also welcome those who may be coming to hear us for the first time, and I hope that we're able to provide you with the kind of information that you're looking for. We do have a lot to cover today, a lot of policy on science all mixed together here. But before we do that, I want to acknowledge a dedication that maybe one of the most special ones that we've ever had on this podcast. I want to remind you, if you don't remember, and I know that none of you will acknowledge you didn't remember, but this Sunday, May 10th is Mother's Day. Mark your calendars. We want to dedicate this episode to all the mothers, grandmothers, step mothers, foster mothers, aunts, and any other maternal figure that helped shape our lives. Being a mother is one of the most thankless but incredibly important jobs around. There is no denying that without mothers and maternal figures alike, we wouldn't have anything in this world. These figures are instrumental in shaping us and supporting us. They often bring so much dedication, care and love to our lives while often sacrificing themselves. And far too frequently the sacrifice goes unrecognized. I know that from my own late mother's perspective. I'd also like to acknowledge that some of us might have strained relationships with our mothers. Some people long to be mothers, but have had great difficulty in that journey to getting there.

Dr. Michael Osterholm: And finally, I know that some of us have also lost mothers, a grief which can weigh so incredibly heavy on our hearts. We're thinking of you folks, too, no matter what your situation might look like. I hope you can take this time to honor a mother or maternal figure in your life this next week. Who knows if words in a card, a bouquet of flowers, or a nice dinner can even begin to express the endless gratitude for all that mothers have done for us. But it surely will start. And in this moment, I want to take the opportunity to acknowledge some very special mothers that today are ever present in everything I do or think about. Why? Because the mother of my children, both my daughter and my son, is a remarkable woman, Peggy Johnston, who I can only have say the most wonderful things about as a mother. And all these years later. It's not just a mother, but she's also an incredibly important figure in the lives of my five grandchildren. Thank you very much, Peggy, for what you do. And the same is true for Fern Peterson, my wife and her three sons, who adore her as they should, as well as their grandson. You have been remarkable models of love, caring and compassion in our lives. Thank you for that. And finally, there's one last special mother, someone that I had the opportunity to call mother on many, many occasions with heartfelt belief that I felt like she was my mother.

Dr. Michael Osterholm: Many of you know, Jim Wappes, our editor here at CIDRAP, a very important figure in our organization. Well, his mother, Lorraine, died this past Monday at age 102. She died peacefully after a long blessed life devoted to family, friends, nurturing, travel and card table memories. She was a remarkable lady. She goes way back in time here. Lorraine has had a long history of accomplishments, including graduating as valedictorian her Cromwell High School in 1941. She earned a bachelor's degree in nursing from the University of Minnesota in 1945. Her first shot was an obstetrics nurse at Saint Francis Hospital in San Francisco. She is someone who has given so much love to others in her life. As her family describes her, she had a ridiculously rich life revolved around faith, family, friends and card playing. We offer our condolences to Lorraine's seven children, their three spouses, 16 grandchildren and 16 great grandchildren. I, for one, will count myself as one of those sons at somewhat of a distance. For years I referred to Lorraine, his mom, and loved every moment of it. What a kind and giving person. So on this Mother's Day, we hope that all the moms can feel celebrated, can feel loved, and can understand their importance in this world and in particular for Lorraine. Thank you so much for the incredible mother you were to so many people for so many years. We will miss you. We love you. Well, and now we move on to that part of the podcast that for some of you, it's time to take a break.

Dr. Michael Osterholm: About 30 seconds. But for the others of you, this is really important. And as we get closer and closer to that summer solstice, that even gets more important. I'm very happy to report that today, May 7th, in Minneapolis, St. Paul sunrise will be at 5:53 am, sunset at 8:26 pm. that's a whole whopping 14 hours, 32 minutes, and 15 seconds of sunlight. But equally important is we're still gaining sunlight at two minutes and 33 seconds a day this week, meaning that the days are only going to get better. Remember on June 20th and 21st this year, the sun length will actually be 15 hours, 36 minutes and 50 seconds. We have more than another hour yet to go in terms of gaining sunlight. Love it. And for those of you who have a very real interest in Auckland, New Zealand, and the Occidental Belgian Beer House on Vulcan Lane today, your sun rises at 7:05 am., sunset at 5:29 9 pm. That's ten hours, 24 minutes and 28 seconds of sunlight. And unfortunately, you're losing sunlight at about one minute and 50s a day. But as I shared with you before, we will be very happy to make certain that you can participate in our sunlight. As your days get darker and hours get brighter. Because you know what? We're going to be looking to you next December for some of the same. So celebrate the sun. It's that time of the year.

Chris Dall: Mike, I want to start with the Paxlovid news, and I'll note that this will be our ID query for today's episode, since we've received a lot of emails asking about the results of these two trials that were published in the New England Journal of Medicine. As I laid out in the introduction, this appears to be a bad news, good news story. Explain that to our listeners.

Dr. Michael Osterholm: Well, let me begin by saying it is a bit of both, but actually I think it's more good news than bad news. And this is a very important point. Also, I just want to remind everyone as we have this discussion around this. Remember, we are not in the same place today in this world of COVID like we were in 2020 to 2023. Today, most of the world has a relatively moderate to high level of immunity to COVID viruses. Just because of our experience with either actual infection or vaccination. The virus itself has changed. Clearly, the days of the number of deaths that we saw with Delta, and even in the early stages of Omicron, is very different than we see with the descendants of Omicron. The virus that has now been around for the last several years. So think of it in that regard that it's a combination of how do we as humans stack up against the virus today compared to what we did back three years ago? So let's get back to the question you asked when you noted the studies here. What we're talking about are two large, what we call open label, randomized controlled trials. Panoramic in the UK and CanTreatCOVID in Canada, published in the New England Journal of Medicine. Together, these studies enrolled just over 4000 Non-hospitalized adults at higher risk for severe COVID-19. These were patients aged 50 and older or younger adults with underlying conditions like diabetes or asthma. Importantly, more than 98% were previously vaccinated. All were treated within five days of symptom onset, and they were randomized to receive either usual care alone or usual care plus antiviral Paxlovid for five days and then with 28 days of follow up.

Dr. Michael Osterholm: Now, the bad news is straightforward. In both trials, Paxlovid was not found to reduce the combined outcome of hospitalization or death. In panoramic though severe events occurred in just 0.8% of patients receiving Paxlovid versus 0.7%. With usual care in can treat COVID, it was 0.6% versus 1.2%. But here's where the good news becomes the more important story. Those event rates are remarkably low, both for the patients receiving Paxlovid and those that didn't. And across both trials, there were zero deaths. That's a profound shift from the earlier epidemiology of the pandemic, where we would have expected a much higher level of deaths to occur. To put that into context, we can look back at the original Paxlovid trial, Epic-hr trial, which showed an 89% reduction in hospitalization and death. But that study was conducted in unvaccinated individuals at a time when baseline risk of a severe outcome was dramatically higher. Over 6% in the placebo group. What's changed since then isn't the antiviral. As I just noted, it's the population and the virus Together, widespread immunity from vaccination and prior infection has driven the risk of severe outcomes way down, particularly in light of the fact that the virus has changed only in a very limited way over the past few years. So what this is really telling us is that the Paxlovid didn't fail in these new trials. In a sense, that's misleading. It's not that the drug stopped working, but rather there was less severe disease to prevent.

Dr. Michael Osterholm: So therefore the drugs action weren't that important in how the outcome actually was settled. In a setting with fewer than 1 in 100 high risk patients are hospitalized. Even effective drug may struggle to show additional benefit. That said, Paxlovid is still doing something clinically meaningful. In both trials, patients who received it had faster recovery times by several days and lower viral loads by the end of treatment. As you know from our previous episodes, we discussed the fact that higher viral loads actually were associated with increased occurrence of long COVID itself. So there is clear antiviral activity and a modest benefit for symptom reduction. The practical takeaway is that we're in a different place now than we were with Paxlovid was first introduced. Rather than being a broadly life saving intervention, Paxlovid is now better thought of as a targeted tool. Dr. H. Clifford Lane, former deputy director for clinical research and special projects at the National Institute of Allergy and Infectious Disease, and Dr. Tony Fauci, former NIAID director, published an editorial in JAMA to accompany the papers from the new trial. In it, they emphasized that using Paxlovid may still make some sense for certain patients, especially older adults and immunocompromised individuals, but clinicians may be more selective in the patients they prescribe it to. So in short, the bad news is that Paxlovid is found to have little impact on severe outcomes among most vaccinated patients. But the very good news is the reason why severe COVID-19 outcomes have become much, much less common today than they were 3 to 4 years ago.

Chris Dall: And Mike, this ties in with the discussion. We had a few episodes back, and with a recent article in STAT titled What Happened to COVID? In that article, several experts shared their view on whether COVID is still a significant threat or if it's become just another virus that makes people sick with cold or flu like symptoms. Where do you stand in this discussion?

Dr. Michael Osterholm: Well, this is a really very important question, Chris. And I think it's one that a lot of us think about, whether we know it or not. And what I mean by that is that we are living in a world where we're still trying to understand what will this virus look like next week, next month, next year, several years out. And we've had a period of time for which most of the activity around COVID has actually been one of a much lower risk for causing serious illness and in many instances, even a lower incidence of infection in our communities. So from that standpoint, when you go through a pandemic like we did with COVID, there's a lot to process. I mean, just consider the fact around six years ago, we all basically watched as life as we knew it changed virtually overnight. Hospitals were overrun, flights were canceled, businesses were closed. Schools shut down. At the same time, thousands of people in this country, sometimes tens of thousands, were dying from this new virus every week. Fast forward to today and things again look very different. Of course, COVID is still here with us, and the pandemic, without a doubt left a lasting mark on society. But as time has passed, I think there's been this slow and gradual return to what some would consider a normal or maybe a new normal.

Dr. Michael Osterholm: With that in mind, I thought that the stat piece you mentioned, written by Helen Branswell and published on April 27th, really did a great job of basically taking a step back and asking the question, where are we right now with COVID? Has it become just another respiratory virus? If you get a chance, I'd encourage you to read the article itself. We'll include the link to it in the podcast notes. But we also recognize that there might be some access issues with a possible paywall on the STAT website. The article asks a very valid question because in many ways it moved in that direction when it comes to severe disease and death. The overall threat has clearly declined. Again, as I mentioned a few episodes back, this was episode 205, Disease Awaits for No. One, published on March 26th. We've gone from a period where we saw more deaths from COVID in a single week in this country than we did throughout all of 2025. There were 26,000 deaths in the US the week of January 3rd to the ninth, 2021, versus 21,000 5000 left in the entire year of 2025. Another way the stat piece captured this trend was by looking at where COVID has ranked among the leading causes of death. In 2021, it was the number three cause of death in the US.

Dr. Michael Osterholm: In 2023, it was the 10th. And by 2024, it was the 15th. So again, this gives you a very clear signal that from an overall population perspective, the burden and severity of COVID have come down in a meaningful way. But that still does not mean the risk has disappeared. Remember, we're still talking about tens of thousands of deaths each year. I just noted that in 2025, we actually saw 21,000 deaths. And we can't overlook the consequences of things like long COVID. These aren't things we associate with the common cold. Maybe it's more influenza like now in terms of burden, but that's a serious disease that we take quite seriously on an annual basis. At the same time, there's still the real possibility that SARS-CoV-2 might evolve in a way that could reshape the risks. Well, I don't think that's likely right now. As I've shared, we have been living in this Omicron era, but that will likely change someday. Now, would that mean we could see something similar to what we saw in the darkest phase of the pandemic? I don't think so at all. But when we are dealing with a virus like this that's constantly evolving and we've seen consequential changes in the past, we must admit we don't know what will really happen. As I noted previously, virtually everyone at this point has some form of immune protection against the virus, which has surely played a substantial role in terms of reducing severity.

Dr. Michael Osterholm: However, that protection isn't exactly permanent and as was noted in the stats story, uptake of vaccines has continually declined. This from the article, quote, "The World Health Organization reported late last year that 13% of older adults and 6% of health workers had a shot in 2024, with most of those doses administered in high income countries. In low and middle income countries, rates of booster uptake have fallen below 1%, even among the high risk groups," unquote. So what does this mean moving forward? Again, if we're not mindful about maintaining this protection, particularly among those at highest risk from serious disease. We could very well see hospitalizations and deaths creep back up. And to me that's really the bottom line message. COVID is no longer the crisis it once was. Surely not. But it's also not something you can just sit back and ignore. I, for one, still get my two doses of vaccine a year because I'm in an older age group and I have some underlying health conditions that may put me at higher risk of serious illness. I do think about those 21000 deaths in 2025, and if I could avoid being one of those numbers, Getting my two doses of vaccine a year are sure worth it.

Chris Dall: Sticking with COVID for a moment, I want to ask you, Mike, about a study on COVID-19 vaccine efficacy that was supposed to be published in March in the CDC's flagship publication, Morbidity and Mortality Weekly Report. The study reportedly showed COVID-19 vaccines cut the likelihood of emergency department visits and hospitalizations in half this past winter, despite thorough review by CDC staff. The study has been blocked from publication in Mmwr by Acting Director Jay Bhattacharya. He says it's because the methodology is flawed. Your response?

Dr. Michael Osterholm: Well, let me just say that this is another one of those moments where I really wish I could say I'm surprised by the actions of current leadership, but unfortunately it's just par for the course at this point. Chris, let me add that it's not just this study that you've highlighted here that is of question today. Earlier this week, we learned of additional studies at the FDA that provided very supportive evidence of the safety of both COVID and shingles vaccines. And that, too, was buried by the FDA and not allowed to be presented publicly as despite the fact that the results were from very, very well designed and carried out studies. But let me go back to the article that you noted. This review had initially cleared through the CDC's long standing and thorough scientific review process. It did get a true review by real experts following the initial approval. Jay Bhattacharya, who is the director of the NIH and also the current acting director of the CDC, delayed and then ultimately blocked the study from publication because of what he considered Methodologic concerns, citing issues with the test negative study design. This is a study design that has been used for years for assessing vaccine effectiveness, and was actually used in CDC's own March. Mmwr publication of how effective flu vaccines were this past season. There is no question that across the world, this is a time tested methodology.

Dr. Michael Osterholm: While not perfect with potential sources of some bias, we have shown that it is a reliable and cost effective way to measure vaccine effectiveness. Effectiveness in this case. Meaning what is the vaccine actually do when it's used in the population? Vaccine efficacy, which we often often talk about, is another measure where it is part of a randomized controlled trial where you're manipulating what is happening as opposed to observing what's happening. And so I just want to point out that the distinction here is very important because we want to know how is this vaccine working every day in the population. That's effectiveness data. And that's the data that we have reliably used test negative control studies for decades and have given us such important information. So let me just say, with any study there are limitations to the design. The fact that I surely support, for example, the test negative design does not account for false positive or false negative test results. It does not account for asymptomatic cases. It also limits the study population to health care seeking individuals, who can also be considered as a strength because it can control for the confounding variables of access to care and care seeking behavior. In other words, if someone who actually seeks out care may also be more diligent about their health, therefore, they may be more likely to be vaccinated.

Dr. Michael Osterholm: So let me just conclude about the use of test negative design studies. I think it's important to acknowledge the limitations of such study designs, especially because each design comes with its own unique set of strengths and weaknesses. But it is a very, very good measure of serious illness, hospitalizations, and deaths that are prevented by these vaccines. And we must remember that no amount of politics is going to change that. Now, back to the issues at hand. The block manuscript on the effectiveness of 2025 2026 COVID-19 vaccines in adults. The study used the vision network data from 253 emergency departments and urgent CARES, and 179 hospitals in seven states. Eligible encounters were people who were seen at one of these medical sites with COVID-19 like illness, and had taken a SARS-CoV-2 test ten days before to three days after the encounter. Encounters with a positive test were the cases, and those with a negative test were the controls. The odds of COVID-19 vaccination among cases and controls were calculated, compared and used to estimate the vaccine effectiveness. This information comes from a leaked copy of the manuscript, and I'm sharing it with you to show that this was a standard use of the test negative control study design. Something had been used, as I pointed out for several decades. For even more context, the study came from the Vision Network, a research effort launched in 2019 between the CDC and multiple health care and public health systems around the country.

Dr. Michael Osterholm: The research focus is to assess the effectiveness of flu, COVID, and RSV immunizations against moderate to severe outcomes. Right at the bottom of the CDC's vision website, the page reads, and I quote, vision uses a test negative control design as well as prospective cohort designs with data collected by participating sites, unquote. This blocked manuscript is a product of CDC's own partnership, using a study design that they openly support on their Vision Network website, and one for which the infectious disease vaccine research community also uses. I don't know about you, Chris, but I have a hard time believing the CDC would be advertising the use of a study design that is not trustworthy. In his own op ed in The Washington Post, Jay Bhattacharya doubled down on the decision, citing concerns about the study design, saying, and I quote, the core problem is that to measure the effectiveness of a vaccine in keeping people out of a hospital, for instance, this method throws away all the data about people vaccinated or not, or who are never hospitalized. Instead, it replaces data with unverifiable assumptions, leading to bias. The vaccine effectiveness estimates this method yields could be an overestimate or underestimate. It's all impossible to tell.

Dr. Michael Osterholm: Unquote. It's clear to me this is an economist who knows very little about study design and methods for assessing vaccine efficacy or effectiveness, a body of scientific information that is readily available and supported by the medical community. For him to write a paragraph like that just suggests to me even more how out of touch he is with scientific reality. Even to the extent that there are limitations, this methodology. Let me be clear they were openly acknowledged in the censored paper and are no different from the limitations that many, many, many other vaccine effectiveness studies that have been published following full peer review process. A process Bhattacharya stated MMR is not subject the articles to. So where does this leave things? I don't think we can ignore the fact that the focus of the censored paper is COVID-19 vaccines, and specifically mRNA technology, even though these findings show great benefits of the vaccine. This administration has been working hard to limit access to it. I don't think this is a matter of questioning the study design used, nor the limitations that exist and are acknowledged by the authors. I think this is a blatant effort to again, limit access to vaccines, and it's just simply unacceptable. This approach to deciding how scientific data is shared by our federal government with the public is simply dangerous.

Chris Dall: Back in November, you may remember, the CDC made a controversial change to a page on its website regarding vaccines and autism. In short, the text on the page was changed from stating the scientific consensus that there is no link between childhood vaccines and autism to saying, quote, studies have not ruled out the possibility that infant vaccines contribute to the development of autism, unquote. Now to the present. Last week, a group of researchers published the results of a survey gauging the impact of that language change. Mike, can you tell our listeners what they found and why it's important?

Dr. Michael Osterholm: The vaccines in autism, disinformation is truly a zombie myth. No matter how many times we try to take it out, it just won't die. The change to the CDC page last year gave that myth even more oxygen. And this new survey gives us real data on the impact. The study, published in science last week, surveyed almost 3000 adults. Respondents were split into three groups. One saw the original CDC language clearly stating the scientific consensus has found no link between autism and vaccines. A second group saw the new CDC page that states falsely that there is a possible contribution of vaccines to autism. And the final group did not see either page and served as a control. Participants were then asked a series of questions about vaccines and their trust in institutions like the CDC. Researchers found that the group that read the current CDC page were more likely to view vaccines at a higher risk and engage in conspiracy style thinking. We're talking about one sentence at the top of a web page, making a substantial difference in people's views on health interventions. I appreciate the efforts these researchers put into documenting something that we're seeing in real time. Even when messaging isn't saying vaccines are blatantly unsafe, confusing, or conflicting information about vaccines leads to mistrust and declines in uptake. There's no easy fix for all the damage that the HHS leadership has caused and continues to cause, but we can do our best to share the best evidence we have and communicate it as clearly and consistently as possible, one on one conversations, whether it's with friends, family, coworkers, or your patients. If you're a health care provider, are the best place where we can likely move the needle.

Chris Dall: Mike, in another recent move by the Trump administration regarding vaccines, Defense Secretary Pete Hegseth recently announced that the U.S. military would no longer require flu shots. Your thoughts.

Dr. Michael Osterholm: Chris, the issue of vaccine mandates is complicated, particularly when it comes to something like influenza. In my recently published book, The Big One, my coauthor Mark Olshaker and I discuss this very issue of vaccine mandates and how it really doesn't make sense to take a one size fits all stance of being pro mandate for all vaccines in all settings, or anti mandate for all vaccines. We outlined four factors that should be considered when assessing whether a vaccine mandate is appropriate for a given vaccine in a given population. First, are there safety concerns that need to be addressed in the population for which we are mandating vaccine use? Second, how effective is the vaccine not only in preventing illness but also even potentially infection? And in addition to have any impact on the transmission of the virus from an infected person to someone not yet infected. Third, what is the duration of protection? And fourth, does the disease for which we recommend a vaccine cause serious illness and death to the point at which the public would accept the mandate as important for individual and public health? When we look at these questions, it's easy to understand why we mandate things like measles vaccination in schools, measles vaccine are safe, highly effective in both in terms of preventing infection and from the virus spreading in that environment. It provides durable protection over time and protects against a virus which can cause severe disease and death. When looking at a mandate for something like influenza vaccination, it gets a little more complicated. We know the vaccine is quite safe, so that isn't a concern. But compared to vaccines typically mandated in school settings like MMR or polio vaccines, the influenza vaccine is not highly effective and does not provide durable protection. It is certainly far better than nothing, particularly when it comes to protection against severe disease and death.

Dr. Michael Osterholm: But even the protection wanes after a few months. After considering these first three factors, it's understandable to reach the conclusion that influenza vaccine mandates for schools and workplaces are probably not necessary. However, our fourth factor to consider whether the vaccine prevents serious illness and death to the point at which the mandate is acceptable applies differently in the population settings. In the military settings where we need troops to remain troop ready. This means we need them to be healthy and ready for action. Well, as I just noted, we may not keep them from becoming infected and even ill. However, ensuring that this population is protected against severe disease is critical not just from a public health perspective, but from an occupational readiness and national security perspective as well. No different from any other health requirements expected of military members. I will be very clear right now. A 50% reduction in serious illness, even among the younger soldiers, is something that we should be using to keep that troop readiness at its highest level. The bottom line is, while I'm not an advocate for influenza vaccine mandates in most settings, the military is one where this type of requirement seems very appropriate. The removal of this mandate, in the absence of any new evidence suggesting that this policy should be changed is disappointing, and I hope that members of the military continue to see the importance of vaccination and choose to protect themselves each year by receiving the flu vaccine. I can tell you for certain, I get my flu shot every year. I will do whatever I can relative to vaccination if it means protecting against serious illness, hospitalizations and deaths. And that should mean the same thing to our troops and our troop readiness.

Chris Dall: Let's turn now to our review of U.S. respiratory activity. Mike, are we done with cold and flu season? And do you have any expectation that COVID might pick up again over the summer as it has in previous summers?

Dr. Michael Osterholm: Well, it seems that the cold and flu season is finally behind us. Flu activity continues to decrease across the board, with outpatient visits for influenza like illness now at levels we are only seen before in October. Colorado is the only state considered to have low flu activity, while the other 49 are considered minimal. There have been 12 additional pediatric deaths reported since our last episode, which means we're now up to 155 for the season. A real tragedy. However, it did compare favorably against what we witnessed in 2025. We had 285 deaths. RSV activity also continues to decline. The national wastewater concentration is very low, with only four states Michigan, Nebraska, Utah and Vermont having moderate concentrations. RSV related hospitalizations and emergency room department visits have continued to decline in every age group and activity. Lastly, COVID-19 activity continues to remain quiet, with wastewater concentrations being considered very low in every region. COVID-19 related hospitalizations and emergency department visits continue to decline as well. So far, I'm not seeing any signs of COVID picking up. That would make me think that we're seeing COVID activity pick up in early summer. But you know me, Chris, I don't like to make predictions about these unpredictable viruses. I often hear people making these predictions based on the assumption that this is a seasonal virus with a summer and a winter flurry of activity. I agree with people that this is a seasonal virus, but only because it happens in every season. I expect that at some point in the future we will see COVID activity increase, but I don't know exactly when that will be. We're going to come up on a time when immunity from previous infection or from boosters is waning in the majority of the population who experience infection or who receive vaccine. And we're not sure of the status or timeline of the fall vaccine, which further complicates what we could see come fall and winter. We will keep you posted on that very important piece of information.

Chris Dall: U.S. measles cases appear to be slowing down, but the CDC recently warned that they will likely pick up over the summer with increased travel. But Mike, is travel related measles that much of a concern given how much local transmission there is in this country right now?

Dr. Michael Osterholm: Chris, measles is here, there and everywhere. As you mentioned, there is considerable transmission happening in the U.S. if you look at since January 1st through April 30th, the U.S. has reported And 814 confirmed cases of measles. Hotspots are shifting compared to the last few months. The major outbreak in South Carolina has officially been declared over, but Utah and parts of Arizona still have substantial and growing case counts. And if you're outside of the US Mountain West region, it's not necessarily good news. There is currently ongoing transmission across 37 jurisdictions, with Texas and Florida both reporting well over 100 cases each. The CDC health alert ahead of summer travel is warranted, but getting on an airplane isn't the only way to pick up measles. If you're living in the United States, travel can introduce more cases, but sustained spread is happening all over the country in these largely under-vaccinated communities. So if you have friends or family who may be at higher risk, either an infant too young to be vaccinated or someone who is immune compromised, you may think carefully about traveling to a known hotspot, but the risk environment around measles has really changed compared to where it was 20 years ago. There are some big picture policy contexts that's worth noting surrounding measles as well. In April, HHS Secretary Robert F. Kennedy Jr. appeared in multiple hearings on the Hill, answering pointed questions from policymakers about his history of spreading anti-vaccine information.

Dr. Michael Osterholm: Policy changes at CDC and the overall agency response to measles outbreaks. Kennedy did his best to distance himself from these issues, claiming, quote, I have nothing to do with these measles outbreaks, unquote, and citing growing measles cases worldwide as the cause of rising numbers in the US. He also points to the fact that trends in lower vaccination rates and rising measles cases begin before he took on his leadership role at HHS. Which leads us to look at the smoking gun of his entire career, discrediting public health scientists and evidence based medicine before he joined the federal government. One bright spot I can add to our measles conversation is that we're seeing advances in how we're able to detect community spread of infectious diseases. In our most recent public health alert, a collaboration between CIDRAP and the New England Journal of Medicine, Evidence Journal authors describe how they used genomic sequencing in Chicago wastewater to detect measles virus. This signal was reported to the local health department and linked to one confirmed measles case that day. Let me also add, we just have had an experience here in Minnesota where, in fact, in the Rochester, Minnesota waste basin, which includes over 140,000 individuals, there was a bump up of activity for measles virus in that wastewater system, only to find out that there actually was a single case of measles in the community at that time that had not yet been diagnosed with measles.

Dr. Michael Osterholm: The fact that you could pick up one case in a waste stream of 140 000 people, to me is just simply remarkable. I don't know how the dilution factors did not ultimately mean you missed the case. And then on top of it, that case, there were two subsequent individuals who had a relationship with the case. One and two weeks later, they developed measles. And yet the wastewater picked up even a higher bump the same day that those two cases were diagnosed, meaning that, again, it was highly effective in that large waste basin and still picking up measles virus. To me, this is almost magic. Surely wastewater is increasingly shown itself to be a valuable and highly sensitive surveillance tool that I hope we can adequately leverage to combat infectious diseases and improve the health of our communities. However, I worry a great deal about this potential as I just attended a meeting recently with senior administration officials who indicated that funding for these programs were being cut. However, again, remember, surveillance alone isn't going to stop an outbreak. Prevention still relies on our ability to build and maintain vaccination coverage. That's what we must keep a central focus.

Chris Dall: Mike, some of our listeners might be wondering and may be a little worried about the story that broke earlier this week regarding an outbreak of hantavirus on a Dutch cruise ship. What can you tell them?

Dr. Michael Osterholm: Well, I find this outbreak to be a great epidemiologic mystery story, but not one of great public health significance. And if you look at the media this past week, surely it made you almost believe that this was going to be the next pandemic virus. There was such emphasis on it. And I can tell you that I had numerous experiences with media where I had to walk them off the edge of the cliff because of the fact that they were convinced that this was a very significant story. It's a curious story. By the time this podcast is actually published, I'm sure there'll be more important information that will be showing up. But as of now, I can say that we have seven cases of what appears to be a hantavirus infection. I understand that one of those cases may actually not be hantavirus. We'll have to wait and see. But at this point, we can clearly say that there is an outbreak on the ship because of the fact that there have been at least two individuals that have now been test positive. Before I get into the details of the outbreak, let me first provide some context on hantavirus. For those who may be unfamiliar, hantavirus infections are very rare, with only 890 cases reported in the US in total since surveillance of the disease began in 1993. That 1993 outbreak involved 33 different cases, 26 of which occurred between April and July of 1993. 17 died. It was focused on the Four Corners area of the United States. The Hantaviruses have been around for hundreds of years.

Dr. Michael Osterholm: The virus is transmitted when dried urine or droppings from rodents are inhaled. These types of exposures typically happen when people clean enclosed spaces with little ventilation, like sheds or attics. Less commonly, it can also be spread through being bitten or scratched by an infected rodent. Eating food contaminated with the virus or touching contaminated objects and then touching your nose or mouth. It's likely that those events are relatively rare. Only one type of hantavirus, the Andes virus, which actually is found in South America and specifically in Argentina, has been found to be transmitted person to person. Hantavirus infections can cause a serious condition called hantavirus pulmonary syndrome, which starts as flu like symptoms but very often progresses to very severe disease, which can include lung and heart failure. Approximately 4 in 10 people who develop hantavirus pulmonary syndrome will die from the disease. Hantaviruses can also cause hemorrhagic fever with renal syndrome, which is fatal in 1 to 15% of patients. As I noted, there are currently seven illnesses associated with this outbreak. Tragically, three individuals have died. One is in intensive care unit in South Africa, and two crew members are experiencing acute respiratory symptoms while still on the ship. It's unclear whether these individuals were infected while on the ship or in one of the stops along the ship's route. The ship departed from Argentina, where there currently are not any known hantavirus cases, and was headed for the Canary Islands. Oceanwide Expeditions, the company operating the ship, has said that they are considering sailing to Spain for passengers to disembark and undergo medical screening, but no definitive plan or date has been announced at the time of our podcast recording.

Dr. Michael Osterholm: So what does all this mean? Well, first of all, let me just say that there are a number of different possible scenarios here. It's very possible that a older couple from Germany, both who have died, actually got on in Argentina and had spent time in Argentina before getting on the ship. It's possible that they actually brought the virus on the ship. And if so, the incubation period of potentially up to several weeks matches up quite well. Also, it could explain how the other individuals on the ship got infected, because remember, the Andes strain, which is the one that we see in Argentina, is the one strain that has actually been associated with person to person transmission. And in fact, in 1996, there was an outbreak in Argentina where the primary mode of transmission was determined to be person to person. And it again involved the Andes strain of the virus. Another possibility here is that it was also picked up on land excursions that the ship made throughout the course of the previous 2 to 3 weeks. As many of you know who have ever traveled by ship, you know that from time to time the ship will stop at port. People will disembark, go explore the local area, and then come back. And finally, the last possibility, which seems unlikely, is that there are actually were rodents on board on the ship or had been on the ship, and there were dried urine and feces that were cleaned up or again, somehow aerosolized.

Dr. Michael Osterholm: I don't know which of these scenarios are likely to be the case. I think the first one actually, I believe is the one that's most favorable, where they actually had individuals bring it on board in an incubation period and actually become clinically ill while on the ship. We'll have to wait and see. But what does all this mean? Well, the first thing that most everyone has missed, there are 17 Americans on board this ship. And guess what? The CDC had no participation in this particular outbreak. Why? Because we have cut all ties with WHO They can no longer use our expertise. Or can we put our expertise to work helping out. This is the first of what will be many such outbreak situations around the world, where it would have been in everyone's best interest to have the United States involved. But we've been forcibly kept out of that area. So stay tuned. Again, this is not going to cause a large outbreak of serious illness, and it's one that hopefully we can put into perspective. I've often said, as you know, that which kills us versus that which hurts us versus that which sometimes makes us very concerned. All can be very, very different. And in this case, I don't think that there's really any evidence that we're going to see any kind of widespread transmission with this virus at all.

Chris Dall: Finally, CIDRAP's Vaccine Integrity Project this week released its review of data on the human papillomavirus, or HPV vaccine. What did the review find, Mike?

Dr. Michael Osterholm: Well, let me just start off and say that I am so proud of the Vaccine Integrity Project staff and what they're doing. It is simply remarkable. It's a very proud moment for us at CIDRAP to be so engaged in this kind of activity, literally providing the kind of evidence we need for the entire country to support the vaccine recommendations that get made. And considering how do we continue to monitor vaccine performance. I'm very excited to share the HPV report, which was officially published on the CIDRAP website on Tuesday of this past week, the Vaccine Integrity Project took this topic on around the time that the Department of Health and Human Services announced that it would be altering the childhood immunization schedule without ACip review, a topic we covered in episode 200 of the Osterholm update. As a reminder, they reduced the number of recommended doses of HPV vaccine to a single dose at 11 to 12 years of age, as opposed to two or more, depending on the circumstances. Not only was this troubling because they circumvented the established procedures, but now the HHS recommendations were inconsistent with formal FDA licensure and with the FDA approved package insert. The goal of the systemic review and meta analysis was to build on the data published in two recent reviews on the topic conducted by Cochrane, a highly reputable group that synthesizes and does meta analysis medical research, ensuring that we could leverage their methods to update the work and provide the most up to date evidence on the safety and effectiveness of HPV vaccines. We were able to find an additional 121 peer reviewed studies that met our search criteria and were published after Cochrane's eligibility time frame, in combination with the Cochrane reviews.

Dr. Michael Osterholm: A total of 274 studies informed our results, synthesizing data across safety, effectiveness and immunogenicity outcomes, encompassing randomized controlled trials and observational studies across safety studies. Our updated search found no credible evidence that HPV vaccination increases the risk of serious adverse events or adverse pregnancy outcomes. Vaccine effectiveness and efficacy studies also showed strong and consistent evidence supporting the role of HPV vaccine in preventing cervical cancer, precancerous lesions, and persistent HPV infection. One of the topics we hope to get more data on was the comparison of one and multi-dose schedules. We found evidence that the outcomes were similar for serious adverse events persistent HPV 1618 infection and protection against precancerous cervical lesions among individuals receiving one, 2 or 3 doses. While this is good news, the field still needs additional information, though, including data from longer term studies demonstrating durability of a single dose protection, especially in males and for non-cervical disease endpoints. Overall, the most recent evidence continues to strongly support the safety and effectiveness of US approved HPV vaccine and remains consistent with prior Cochrane findings. The involvement of the Cochrane researchers was critical in shaping the methods of this review, and they signed on as coauthors of the report posted online. I also want to acknowledge the huge contributions of the Vaccine Integrity Project research team at CIDRAP, which includes many members of our podcast team. An incredible amount of work went into making this review happen and providing medical specialty societies and the American public with clear evidence based information on HPV vaccination.

Chris Dall: And Mike, I also want to highlight for our listeners a story that was published Tuesday along with the VIP report by CIDRAP news reporter Liz Szabo. It's a story that features a survivor of cervical cancer, a woman who was born long before the vaccines were approved. And it tells the story of her struggle with the diagnosis and with treatment. And it's really a testament to the significance of these vaccines. We will have a link to that story on the podcast page. And now it's time for this week in public health history. Mike, what are we celebrating this week?

Dr. Michael Osterholm: Well, let me start out by saying this is an interesting one. Okay. I hope the audience takes note of just how interesting this is. Today, May 7th, marks the founding of the American Medical Association back in 1847. That's nearly 180 years ago, the AMA was founded for a variety of reasons. You have to remember that back in the mid 1850s, modern medicine was nowhere near what it's like today. Misinformation and medical hoaxes were rampant. So maybe that's not unlike today. But the medical hoaxes were different back then, like eyedrops full of opium and alcohol. The AMA was founded in part to tackle these harmful practices and regulate treatments for all. But another goal, the AMA, was to foster healthier and friendlier relationships between doctors. In fact, the founding of the AMA can be traced back to a gun duel between two feuding doctors a couple of decades earlier. Believe it or not, scuffles between doctors were actually pretty common. Back in the 1800s, the duel in question was challenged between two doctors, Daniel Drake and Benjamin Dudley. The two had disagreements back in med school, which snowballed into an ongoing feud over the span of years, Drake and Dudley even went back and forth at each other in newspapers at the time.

Dr. Michael Osterholm: This disdain came to a boiling point when Dudley challenged Drake to a duel after he felt his reputation was at stake. Drake thought the idea was silly, but a colleague, William Richardson, stepped up. Dudley and Richardson met in the woods, took ten steps from each other, raised their pistols and shot at each other. Yes, you heard that right. Two doctors shooting each other in the forest. Pretty crazy, huh? Richardson missed his shot but was struck by Dudley in the groin. Ouch. Luckily, there was a third doctor watching who assisted Dudley to help save Richardson's life by stopping the bleeding. The duel outraged citizens and doctors alike, which eventually led to a call for a society where doctors could be civil together. Eventually, the AMA was formed. Since its formation, the AMA has strived to keep up to date with best ethical practices in medicine. They also publish JAMA, one of the most widely circulated medical journals in the world. Needless to say, it's come a long way from dueling doctors in the middle of the woods.

Chris Dall: Mike, we've really covered the waterfront today, from Paxlovid to dueling doctors. What are your take home messages for today?

Dr. Michael Osterholm: Well, Chris, first of all, the Paxlovid story is a very important one. Important in the sense that it's given us a new perspective on where we're at with COVID. First of all, the drug didn't really fail in the two studies we referenced today, as much as the patients didn't needed the drug period, if they had never gotten the drug, they would have done just fine. That is a reflection of the new World Order of COVID. And as we discussed today, that's good news. The question is, how long will that detente between the virus and us last? And even having said that, I will must continue to admit that, in fact, 25000 deaths a year is still a real challenge with COVID. But fortunately, it's not like 26,000 deaths a week in the height of the pandemic. The second piece is the respiratory infections are down and out. We are, I think, at a very good point right now with all three of them influenza, RSV and COVID. I don't expect to see any major increases in any of the three in the days ahead. The one that might in fact, give us a challenge later in the summer could be COVID, but we'll watch that carefully. And finally, as I noted in the hantavirus story, that's what kills us versus that which hurts us versus that which scares us, are all different in terms of how we perceive the risk of a given infectious agent right now. Being scared means that we are very concerned about this virus, when in fact, it is way down on the list of infectious disease challenges in terms of number of cases, number of deaths. I think we will see that the outbreak will be solved in the next few days, and hopefully the individuals who are still currently ill or who may become ill over the next few days actually do well.

Chris Dall: And what is your closing song for this episode, Mike?

Dr. Michael Osterholm: Well, in keeping with Mother's Day and the dedication that we had at the beginning of this podcast, I wanted to do something that would again celebrate that. And there's an artist who seems to have written a song for almost every moment that we have. I picked a song today from Taylor Swift. The song is "The Best Day." It's a song written and recorded by her for her second studio album, fearless, in 2008. It was produced by her and Nathan Chapman. The Best Day is an understated folk rock song with a country rock arrangement with lyrics dedicated to Swiss parents. Most of the verses being to her mother. A music video containing the home footage, edited by Swift and released on May 1st, 2009 as part of a special Mother's Day promotion through the Big Machine Records. Swift actually recorded the Best Day and edited an accompanying home video without telling her mother, Andrea, so as to surprise her for Christmas. Swiss mother recalled that when her daughter showed her the song in the video on Christmas Eve, "that's when I lost it, and I've lost it pretty much every time I've heard that song since". That really is what this is all about. I wish our mothers could all feel empowered to lose it, based on a special day called Mother's Day and the recognition that we all have for their important role in our lives. So here it is, the song The Best day. I'm five years old. It's getting cold. I've got my big coat on. I hear your laugh and look up smiling at you.

Dr. Michael Osterholm: And I run and run past the pumpkin patch and the tractor rides. Look now the sky is gold. I hug your legs and fall asleep on the way home. I don't know why all the trees change in the fall. But I know you're not scared of anything at all. Don't know if Snow White's house is near or far away. But I know I had the best day with you today. I'm 13 now and don't know how my friends could be so mean. I come home crying. And you hold me tight and grab the keys. And we drive and drive. Until we found a town far enough away. And we talk and window shop. Till I've forgotten all their names. I don't know who I'm going to talk to at school now. But I know I'm laughing on the car ride home with you. I don't know how long it's going to take to feel okay, but I know I had the best day with you today. I have an excellent father. His strength is making me stronger. God smiles on my little brother inside and out. He's better than I am. I grew up in a pretty house and I had space to run and had the best days with you. There was a video I found from back when I was three. You set up the paint set in the kitchen, and you were talking to me in the age of princesses and pirate ships and the Seven Dwarfs. And daddy's smart. And you're the prettiest lady in the whole wide world. And now I know why all those trees change in the fall.

Dr. Michael Osterholm: I know you're on my side. Even when I was wrong. And I love you for giving me your eyes. Staying back and watching me shine. And I don't know if you know. So I'm taking this chance to say that I had the best day with you today. Taylor Swift. Thank you very much for joining us. I hope that we were able to give you some helpful information today. It seems as if the world is swimming in disinformation, and we'll just continue to do our part to try to help you wade through all of that. All I can say in these times of craziness, and sometimes to the point of almost despair. Stay with it. Stay positive. Stay kind. I know that's hard to hear. I know that many people may even say, well, how can you do that? Or why should you even talk about it? We just need to be reminded how important it is to be kind. It makes a difference. So thank you. We'll be back with you in two weeks. And by that time, God knows what's going to be happening in the world. But we'll be there with you. I can't again also say enough about the podcast crew. Thank you so much for your help with this podcast and to you, the podcast family. You mean the world to us. I really mean that from the bottom of my heart. You mean the world to us. Thank you, thank you and thank you. Be kind, be safe. Thank you.

Chris Dall: Thanks for listening to the latest episode of the Osterholm update. If you enjoy the podcast, please subscribe, rate and review wherever you get your podcasts. And be sure to keep up with the latest infectious disease news by visiting our website, CIDRAP.edu. This podcast is supported in part by you, our listeners. The Osterholm update is produced by Sydney Redepenning, Elise Holmes and Ruby Guthrie. Our researchers are Cory Anderson, Meredith Arpey, Leah Moat, Emily Smith, Claire Stoddart, Angela Ulrich and Mary VanBeusekom.