News Scan for Nov 03, 2022

News brief

Flu on the rise in Northern Hemisphere regions, with H3N2 still dominant

Flu activity is starting to rise in parts of the Northern Hemisphere, including Europe and North America, the World Health Organization (WHO) said in its latest global flu update, which covers data through Oct 16.

In central Asia, Kazakhstan reported increased activity, mainly from influenza B. In western Asia, flu rose in some countries, including those on the Arabian Peninsula, and in southern Asia, flu activity remained low, except in Iran.

Tropical African and South American countries reported low flu activity. And while most Southern Hemisphere countries reported further decreases, some temperate South America countries reported increases, including Argentina and Chile.

Of respiratory samples that tested positive for flu at national flu labs during the first half of October, 90.4% were influenza A. Of subtyped influenza A viruses, nearly 82% were H3N2. Of characterized influenza B viruses, all belonged to the Victoria lineage.
Oct 31 WHO global flu update


Groups detail support for Uganda's Ebola vaccine trials

The Coalition for Epidemic Preparedness Innovations (CEPI), Gavi, and the WHO today spelled out a plan to speed up research during Uganda's ongoing Ebola outbreak, with a goal of ensuring that the country has access to doses of investigational vaccines against the Sudan Ebola virus.

Currently, there are no licensed vaccines or treatments against Sudan Ebola. Uganda's health ministry recently announced that three candidate vaccines will be tested in the current outbreak setting. They are from Oxford University in the United Kingdom and Sabin Vaccine Institute and Merck in the United States.

In a joint announcement today, the groups also said they would facilitate the scale-up and access to any vaccines that are licensed following the clinical trials, which will be facilitated by Makerere University Lung Institute in Uganda.
Nov 3 CEPI, Gavi, WHO joint statement

COVID-19 Scan for Nov 03, 2022

News brief

Omicron mRNA vaccine efficacy lower, more fleeting in kids than teens

COVID-19 vaccination of children in Qatar was tied to low to modest, rapidly waning protection against infection with the Omicron variant, but teens had slightly more robust, longer-lasting immunity, suggests a study published yesterday in the New England Journal of Medicine (NEJM).

A team led by Weill Cornell Medicine-Qatar researchers used national databases and rapid antigen test results from healthcare facilities starting on Jan 5, 2022, to evaluate the efficacy of two doses of the Pfizer/BioNTech mRNA COVID-19 vaccine in children aged 5 to 11 years amid Omicron predominance and in adolescents aged 12 to 17 before and during Omicron.

In Qatar, adolescents were vaccinated starting in February 2021, followed by children aged 5 to 11 a year later. Median follow-up was 69 days in children and about 44 and 156 days before and during Omicron in adolescents.

Vaccine effectiveness (VE) of the 10-microgram (μg) primary series in 37,456 children against infection was 25.7% (95% confidence interval [CI], 10.0% to 38.6%). VE was strongest immediately after the second dose (49.6%; 95% CI, 28.5% to 64.5%) but fell to a statistically insignificant 11.0% (95% CI, −26.8% to 37.5%) after 3 months.

Among children 5 to 7 years, VE was 46.3% (95% CI, 21.5% to 63.3%), while it was 16.6% (95% CI, −4.2% to 33.2%) among those aged 8 to 11.

VE of two 30-μg vaccine doses in adolescents was 30.6% (95% CI, 26.9% to 34.1%), although many had been vaccinated months earlier. VE was 35.6% (95% CI, 31.2% to 39.6%) among adolescents 12 to 14 years and 20.9% (95% CI, 13.8% to 27.4%) among older teens.

Before Omicron, VE among 46,634 adolescents was 87.6% (95% CI, 84.0% to 90.4%) and waned slowly after dose 2. Amid Omicron, VE among 35,806 adolescents was 30.6% (95% CI, 26.9% to 34.1%). The authors said the more robust response in adolescents could be due to the larger antigen dose.

"Our findings suggest the need to reconsider the value and strategies of vaccinating healthy children in the omicron era with the use of currently available vaccines," they wrote.
Nov 2 NEJM study


Report: COVID-19 likely spread through floors, walls of quarantine hotel

The Omicron SARS-CoV-2 variant was likely transmitted through the floors and walls of a quarantine hotel in Taiwan in December 2021, adding to a large body of evidence that aerosol transmission plays a significant role in outbreaks and clusters, according to a report yesterday in Emerging Infectious Diseases.

Taiwan required inbound international travelers to quarantine in hotels for 7 to 14 days following a negative polymerase chain reaction (PCR) test before air travel to the island. In the weeks preceding the Lunar New Year celebrations of 2022, such hotels were in high demand, and many commercial hotels converted to quarantine hotels.

The report details three case-patients who lived in nonadjacent rooms on different floors of the quarantine hotel in the last week of December of 2022, and had no direct contact during their stay. All three tested negative for the virus within 72 hours of boarding flights to Taiwan, but tested positive on PCR tests while staying at the hotel.

The case-patients traveled from China, New York, and Japan, respectively, and the authors deduced that the traveler from New York likely had an emerging case of COVID-19 due to the Omicron strain at the time of travel.

Old tunnels and air conditioner units were found to transmit aerosols throughout the hotel. A small-scale tracer-case experiment showed multiple air leaks in the building, sufficient to spread virus aerosols.

"In the setting of under-ventilated indoor environments with recirculated air conditioning systems, the exhaled aerosol might remain suspended for a prolonged period and disperse across a long range," the authors concluded. "It is plausible, then, that a high concentration of virus-laden aerosol might have accumulated in a poorly ventilated room and might have been transported by the airflow across different rooms through the structural defects."
Nov 2 Emerg Infect Dis


Pfizer and BioNTech start clinical trial of flu-COVID combo vaccine

Pfizer and BioNTech today announced the launch of a phase 1 clinical trial to assess the safety, tolerability, and immunogenicity of its candidate combination mRNA vaccine that targets influenza and COVID-19.

The vaccine—given as a single dose— combines Pfizer's investigational quadrivalent mRNA flu vaccine, which is in phase 3 trials, with the updated COVID-19 booster that targets the original SARS-CoV-2 virus plus BA.4/BA.5 Omicron subvariants from Pfizer and BioNTech.

Ugur Sahin, MD, BioNTech's cofounder and chief executive officer, said the goal is to provide people with an efficient way to protect against two severe respiratory diseases that involve evolving viruses that require adapted vaccines. "The data will also provide us with more insights on the potential of mRNA vaccines addressing more than one pathogen. This will help us to further develop our infectious disease pipeline to deliver on patient centric vaccination approaches," he said.

The trial is under way in the United States and has a goal of enrolling 180 healthy adults ages 18 through 64. Participants will be followed for 6 months. The first participant was immunized this week.
Nov 3 BioNTech press release

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