• The World Health Organization (WHO) COVID-19 emergency committee is meeting today to discuss if the situation still warrants a public health emergency of international concern (PHEIC) which has been in effect since Jan 30, 2020. The group's director-general has said though the changing virus is still capable of causing more waves of infections and deaths, the WHO hopes that the end of the PHEIC can be declared sometime this year. The WHO will hold a media briefing on global health issues tomorrow and will likely announced the committee's recommendation.
• The Independent Panel for Pandemic Preparedness and Response, which has been tracking capacities at the global level, this week released a roadmap for better protecting the world against pandemic threats. The panel said applying lessons learned during COVID-19 offers a once-in-a-lifetime opportunity to get pandemic preparedness right, adding that regional groups and large institutions are in an increasingly strong position to strengthen capacities. The group is headed by Ellen Johnson Sirleaf, Liberia's former president, and Helen Clark, who is New Zealand's former prime minister.
• The US Food and Drug Administration (FDA) vaccine advisory group will meet on June 15 to discuss and make recommendations on the strains to include in the 2023-24 COVID-19 vaccines, according to a notice posted today in the Federal Register. The meeting will be virtual and open for viewing by the public.

In Australians who had never previously had COVID-19, a three-dose COVID-19 vaccination series was 42.0% effective against infection and 81.7% effective against hospitalization or death during Omicron, a new study in Emerging Infectious Diseases finds.

The study was conducted in Western Australia, which had low case counts of COVID-19 until the Omicron variant began to spread beginning in January 2022. The region had strict travel restrictions and local outbreak measures that had significantly reduced the number of COVID-19 cases in the community, leaving a population with low levels of natural immunity, but high (more than 90%) vaccination rates.

To conduct the study, the authors compared the vaccination history of 188,950 positive case-patients and 188,950 negative matched controls from specimens collected from  February 1, 2022, to May 31, 2022. Of the 377,900 study participants, 30,420 (8%) were unvaccinated at the time of testing, 84,237 (22%) had received two doses, and 263,243 (70%) had received three doses, the authors said.

Vaccine effectiveness (VE) for preventing lab-confirmed infection was 24.9% (95% confidence interval [CI], 21.2% to 28.4%), increasing to 42.0% (95% CI, 40.2% to 43.6%) for people who had received three doses of vaccine. VE was highest (70.7%) among those who had gotten a booster no more than 30 days before testing.

Ancestral strain vaccines still provide substantial protection against severe disease caused by newer variants.

Severe cases of COVID-19, defined by hospitalizations, and deaths were rare in the study. VE against severe disease for two doses of vaccine was 41.9% (95% CI, 4.8% to 64.5%) and increased to 81.7% (95% CI, 73.9% to 87.2%) for three doses.

The authors concluded, "Our study definitively demonstrates that ancestral strain vaccines still provide substantial protection against severe disease caused by newer variants among a population free from potential confounding of previous immunity conferred by natural infection with an earlier variant."

New data from a nonprofit hospital safety group show that the average rate of three healthcare-associated infections (HAIs) hit a 5-year high in US hospitals during the COVID-19 pandemic and have remained high.

The data from the latest Leapfrog Hospital Safety Grade, covering late 2021 through 2022, showed that the average standard infection ratios for central line-associated bloodstream infections (CLABSIs), methicillin-resistant Staphylococcus aureus (MRSA) infections, and catheter-associated urinary tract infections (CAUTIs) rose by 60%, 37%, and 19%, respectively, compared with the period immediately before the pandemic. Thirty-two of 50 states saw significant increases in CLABSIs, 18 in MRSA infections, and 11 in CAUTIs.

The data add to the growing body of evidence that the pandemic's impact on hospital staffing and resources has impeded infection prevention and control efforts. Data released by the Centers for Disease Control and Prevention in 2021 showed hospitals in 12 states saw significant increases in CLABSIs, CAUTIs, and ventilator-associated events (VAEs) in 2020 compared with 2019. Prior to 2020, rates of HAIs at US hospitals had been declining.

Alarming findings like these indicate hospitals must recommit to patient safety and build more resilience.

"The dramatic spike in HAIs reported in this Safety Grade cycle should stop hospitals in their tracks—infections like these can be life or death for some patients," Leah Binder, president and CEO of The Leapfrog Group, said in a press release. "We recognize the tremendous strain the pandemic put on hospitals and their workforce, but alarming findings like these indicate hospitals must recommit to patient safety and build more resilience."

In a statement emailed to reporters, Society for Healthcare Epidemiology of America President Deborah Yokoe, MD, MPH, said the increases are likely related to overburdened staff and the diversion of infection prevention and antimicrobial stewardship resources to pandemic response.

"Despite the financial challenges that many healthcare facilities currently face, this new data highlights the need for healthcare facilities to invest in the infection prevention and control programs that spearhead this work and to build the system-wide infection prevention infrastructures required to create and sustain improvements over time, even in the face of the next public health crisis," Yokoe said.

As flu levels taper off in the Northern Hemisphere, some Southern Hemisphere countries are reporting increased detections over the past few weeks, the World Health Organization (WHO) said in its latest update, which covers the first half of April.

In the tropical part of South America, Peru reported a spike in activity involving the 2009 H1N1 strain, with a few other countries reporting slight increases. In temperate zones of the Southern Hemisphere flu activity rose slightly in Australia and Chile, mainly due to H1N1.

Elsewhere, Hong Kong reported a sharp increase in H1N1 activity, while Bhutan and Sri Lanka reported increased activity.

In the Northern Hemisphere, levels declined. North America's indicators returned to interseasonal levels, with H1N1 and influenza B circulating in the United States and influenza B predominant in Canada. Europe's flu levels declined to the epidemic level, with most of the region experiencing a wave of influenza B activity following the earlier wave of influenza A.

Testing at national flu labs in the first part of April found that 75.5% of positive flu samples were influenza A, and, of subtyped viruses, 70.2% were H1N1. All influenza B viruses belonged to the Victoria lineage.

The UK Health Security Agency (HSA) today reported a rise in measles cases and urged parents and guardians to ensure that children are up-to-date with their measles, mumps, and rubella (MMR) vaccine doses.

In a statement, the HSA said that, from January through April 20, 49 measles cases have been reported, which is already approaching the 54 cases reported for all of 2022. Most of the infections have been reported in London, but some have been reported in other areas and some have been linked to international travel.

Officials said the number of children vaccinated against measles has declined in recent years. For example, uptake of the first dose in 2-year-olds is 89%, and uptake of two doses in 5-year-olds is 85%, well below the World Health Organization's 95% targets, which are levels set to achieve and maintain elimination.

The HSA said routine childhood immunizations fell globally during the pandemic, and measles is now circulating in many countries. It said the WHO has warned that Europe is likely to experience a resurgence unless countries conduct catch-up vaccine campaigns.