CDC ends investigation into sprout-linked E coli outbreak that sickened 51

The Centers for Disease Control and Prevention (CDC) said in an update yesterday that it has concluded its investigation into a 10-state outbreak of Escherichia coli linked to contaminated clover sprouts that sickened 51 people, up 12 from the agency's Mar 19 update.

CDC traced the outbreak to a seed lot that supplied Chicago Indoor Garden, which recalled all products containing red clover sprouts on Mar 16. The same seed lot was the source of a 2019 outbreak of the same strain of E coli from clover sprouts.

Eighteen of 32 people interviewed by the CDC (56%) reported eating sprouts in the week before their illness. No outbreak-related deaths occurred, but three people were hospitalized. Patients' symptoms began from Jan 6 to Mar 15.

The CDC said that, while the outbreak appears to be over, "raw and lightly cooked sprouts are a known source of foodborne illness. CDC recommends that consumers, restaurants, and other retailers always follow food safety practices to avoid illness from eating sprouts."

These measures include cooking sprouts thoroughly, asking that raw sprouts not be added to restaurant food, checking sandwiches and salads to be sure they don't contain raw sprouts, and avoiding raw sprouts of any kind in children, older adults, pregnant women, and people with compromised immune systems.

The CDC advises retailers to buy sprouts from growers that follow the Food and Drug Administration Sprouts Guidance.
Apr 22 CDC update
news scan
Mar 19 CDC food safety alert


WHO: 6 recent DRC Ebola cases tied to persistent virus source

The World Health Organization (WHO) today posted an update on the six new Ebola cases reported since Apr 10 in the Democratic Republic of the Congo (DRC) outbreak, all in Beni, noting that all seem to be linked to earlier transmission and that features of some of the cases pose a high risk of community spread.

Of the newly confirmed patients, four died, including two in the community, which raises the risk of wider spread. Of the three newest cases, two were registered as contacts, but none were regularly followed because of insecurity challenges and community resistance.

One of the two patients who is still alive is receiving care in an Ebola treatment center. The other is still in the community, and response teams are working with residents to bring him or her to an Ebola treatment center for care and to prevent further transmission.

For the recent cases, 762 contacts have been identified, and 602 (79%) are being monitored. Genetic analysis of samples from the six patients shows a link to cases that were confirmed in July 2019, suggesting a persistent infection source, such as direct contact with the body fluids of a survivor.

So far, 3,461 cases have been reported in the DRC's outbreak, 2,279 of them fatal. The WHO has asked donors for $20 million to keep the outbreak response going through early May.
Apr 23 WHO outbreak update


WHO says immunization gains could be lost in light of COVID-19

The WHO warned today in a separate report that shutting down immunization campaigns and routine services in light of the COVID-19 pandemic could increase the risk of vaccine-preventable outbreaks.

"Disease outbreaks must not remain a threat when we have safe and effective vaccines to protect us," said Tedros Adhanom Ghebreyesus, PhD, WHO director-general. "While the world strives to develop a new vaccine for COVID-19 at record speed, we must not risk losing the fight to protect everyone, everywhere against vaccine-preventable diseases. These diseases will come roaring back if we do not vaccinate."

Measles, polio, diphtheria, and yellow fever are the top concerns for WHO officials, who worry COVID-19 may disrupt immunizations services or prevent parents from seeking routine childhood immunizations. To illustrate this fear, the WHO said a deadly measles outbreak last year in the DRC was made worse by that country's ongoing battle against an Ebola outbreak (see previous scan).

Currently, the WHO recommends a temporary pause of  preventive immunization campaigns where there is no active outbreak of a vaccine-preventable disease.
Apr 23 WHO news release


WHO warns COVID-19 burden could boost African malaria deaths

With countries in sub-Saharan Africa accounting for a small but increasing proportion of global COVID-19 cases, countries have a critical window of opportunity take steps to minimize disruptions in malaria prevention and treatment services, the WHO said today in yet another report.

It urged countries to move fast and distribute insect-treated nets and antimalaria medications and do their best to maintain those essential control services. The WHO warned that severe disruptions could double malaria deaths compared with 2018.

In making its recommendations, the group looked at nine different pandemic-related disruption scenarios for 41 countries to estimate potential increases in cases and deaths. The worst-case scenario, which involved the suspension of insecticide-treated net campaigns and a 75% cut in access to malaria medications, estimated that deaths this year could reach 760,000, double that of 2018. "This would represent a return to mortality levels last seen 20 years ago."

The WHO also advises speeding up mass vector control campaigns and commended Benin, the DRC, Sierra Leone, and Chad for starting their bed net campaigns during the pandemic.
Apr 23 WHO statement


Monoclonal antibody may enhance anthrax vaccine protection, study finds

A phase 4 study has discovered that co-administration of the monoclonal antibody raxibacumab with Anthrax Vaccine Adsorbed (AVA) does not negatively affect AVA immunogenicity, suggesting that combining the two might provide added benefit in people who may have inhaled spores containing Bacillus anthracis.

In the noninferiority study, published yesterday in The Lancet Infectious Diseases, researchers randomly assigned 573 healthy volunteers 18 to 65 years old in a 1:1 ratio to receive either 0.5 microliters (mL) subcutaneous AVA on days 1, 15, and 29 or a 40 milligrams per kilogram intravenous infusion of raxibacumab right before AVA on day 1, followed by AVA only on days 15 and 29 at three US centers from Feb 24, 2015, to Jun 6, 2017.

They found that the geometric mean concentration (GMC) of anti-protective antigen antibodies was 26.5 micrograms (μg)/mL (95% confidence interval [CI], 23.6 to 29.8) in the 276 participants given only AVA versus 22.5 μg/mL (95% CI, 20.1 to 25.1) in the 269 given AVA plus raxibacumab.

The between-group ratio was 1.18 (90% CI, 1·03 to 1·35; P = 0·0019), which met the defined noninferiority margin and supports the hypothesis that the addition of raxibacumab doesn't undermine the vaccine's efficacy. Adverse event rates in the two groups were similar, at 87 (30%) of 286 in the AVA group versus 80 (29%) of 280 in the AVA-plus-raxibacumab group; no serious adverse events were reported.

In a commentary in the same journal, Michael Norris, PhD, and Jason Blackburn, PhD, of the University of Florida in Gainesville, said that raxibacumab "is an effective, safe, and valuable addition to the current AVA vaccination regimen for anthrax post-exposure prophylaxis, with the capacity to substantially reduce morbidity and mortality of human infection," noting that its efficacy against anthrax caused by new and diverse forms of anthrax pathogens is unknown.

The study was sponsored by the US Biomedical Advanced Research and Development Authority (BARDA) and GlaxoSmithKline, which produced raxibacumab until it sold the drug to Emergent BioSolutions in 2017.
Apr 22 Lancet Infect Dis
abstract and commentary

Stewardship / Resistance Scan for Apr 23, 2020

News brief

Antibiotic messaging survey finds empowerment more effective than fear

Public campaigns that use "fear-based" messaging to reduce antibiotic use and antimicrobial resistance (AMR) may be more effective if they also contain messages that empower patients to self-manage without antibiotics, UK researchers reported in a study published today in BMC Medicine.

To test the efficacy of fear-based messages, both with and without empowering messages regarding influenza-like illness (ILI) symptoms being easily self-managed without antibiotics, researchers from the National Institute for Health Research Health Protection Research Unit sent a survey to 4,000 UK respondents.

The respondents were randomized to receive three different messages about antibiotic use and AMR: one contained a "fear-only" message, and the other two were "mild-fear-plus-empowerment" and "strong-fear-plus-empowerment". The main outcomes measured were whether the messages were "very/somewhat new" to respondents and whether the messages had an effect on the likelihood of visiting a doctor and requesting antibiotics for ILI.

Overall, 25.2% of respondents said the message they received was "very/somewhat new," with small but significant variation between messages. Of those for whom the respective information was "very/somewhat new," only those given the "strong-fear-plus-empowerment" message were significantly less likely to request antibiotics if they visited a doctor for an ILI (182/388, 46.9%), versus 116/336 (34.5%) of those who received the "mild-fear-plus-empowerment" message and 85/285 (29.8%) who received the "fear-alone" message.

Those for whom the respective information was not "very/somewhat new" said they would be less likely to request antibiotics for ILI across all messages. The three messages had analogous self-reported effects on likelihood of visiting a doctor and in subgroups defined by believing antibiotics would "definitely/probably" help an ILI. 

"Consistent with meta-analyses on the effectiveness of fear-based messages in other healthcare areas, the evidence from this study suggests that fear-based messages about antibiotics and AMR are more likely to be effective in reducing consultations and antibiotic requests, especially among those with low AMR awareness, if they include 'empowering' information about effective self-management without antibiotics," the authors conclude.
Apr 23 BMC Med study


Flu vaccination helped reduce antibiotic prescriptions, study finds

A study led by researchers from the US Centers for Disease Control and Prevention has found that influenza vaccination averted 1 in 25 antibiotic prescriptions among outpatients with acute respiratory illness (ARI). The results appeared today in Clinical Infectious Diseases.

For the study, researchers enrolled outpatients 6 months or older who had ARI and were treated at 50 to 60 healthcare facilities that belong to the US Flu Vaccine Effectiveness (VE) Network from 2013 through 2018.

To examine the evidence for the role of influenza vaccination on antibiotic prescribing among these outpatients, they collected data on antibiotic prescribing and diagnosis codes for ARI syndromes and calculated VE by comparing vaccination odds among influenza-positive test cases to test-negative controls. They estimated the number of ARI visits and antibiotic prescriptions averted by influenza vaccination using estimates of VE, coverage, and prevalence of antibiotic prescriptions and influenza.

Over the 5-year study period, among 37,487 enrolled patients, 18,807 (50%) were vaccinated against influenza, and 9,659 (26%) were considered influenza-positive. Antibiotics were prescribed to 36% of patients with ARI and 26% of influenza-positive patients. The top three most prevalent ARI syndromes were viral upper respiratory tract infection (47%), pharyngitis (18%), and allergy or asthma (11%). After adjusting for potential confounders, the overall VE against lab-confirmed influenza was 35% (95% confidence interval [CI], 32% to 39%).

Based on the VE and vaccination coverage, the researchers estimate that vaccination prevented 5.6% of all ARI syndromes, with a range of 2.8% (sinusitis) to 11% (clinical influenza) for each of the clinical syndromes, and 3.8% (95% CI, 3.6% to 4.1%) of antibiotic prescriptions among ARI outpatients.

The authors of the study say the findings are consistent with previous research that suggests antibiotics are overprescribed for ARI syndromes for which they are not indicated. They conclude that improvements in vaccine coverage and effectiveness, combined with efforts to reduce antibiotic use and improve diagnosis and recognition of influenza, are important strategies for reducing antibiotic prescribing for these syndromes.
Apr 23 Clin Infect Dis abstract


Review highlights areas for improvement in UK AMR strategy

A review of the UK government's first 5-year AMR strategy by the Policy Innovation and Evaluation Research Unit (PIRU) at the London School of Hygiene and Tropical Medicine has identified several areas for improvement in both human and animal health that could help strengthen implementation of future AMR policy.

The first UK AMR 5-year strategy, launched in 2013, aimed to slow the development and spread of AMR through improved antibiotic prescribing and infection prevention measures in human and animal health. The PIRU evaluation explored how the strategy was implemented and how AMR is being managed in local health services across the UK in the pig and poultry industries and companion animals.

Among the findings of the review is that while there has been considerable progress in the collection and sharing of AMR data in human health settings, there was a lack of awareness among some local National Health Service (NHS) staff of all the data that are available. In addition, some hospitals have found it easier to meet some AMR control targets than others, and there have been problems introducing and using diagnostic tests designed to distinguish between bacterial and viral infections.

On the animal health side, the review found that livestock sectors were in different stages of improving the way they use antibiotics and collect data, with some private industry groups and professional organizations demonstrating leadership. But more data over a longer period are needed to assess efforts to reduce antibiotic use in animals, and more could be done to harmonize data on AMR and antibiotic use across the human and animal health sectors so that they can be compared more easily. Veterinarians also noted that talking with pet owners about antibiotic use is challenging due to short consultations.

Finally, the review found that patients and members of the public haven’t been involved enough in the development and implementation of the strategy and that increased public involvement could lead to better ways of managing AMR.
Apr 22 PIRU UK AMR strategy evaluation

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