WHO experts swap out 2 flu A strains for next Northern Hemisphere vaccine
The World Health Organization (WHO) today announced that its influenza vaccine strain selection committee has made its recommendations for the Northern Hemisphere's 2021-22 flu season, which swaps out the two influenza A strains for both the egg-based and cell-based or recombinant vaccines.
For the egg-based vaccines, they recommend replacing the current 2009 H1N1 vaccine strain (A/Guangdong-Maonan/SWL1536/2019) with A/Victoria/2570/2019 and replacing the current H3N2 component (A/Hong Kong/2671/2019) with A/Cambodia/e0926360/2020.
For cell-based or recombinant versions, they recommend replacing the H1N1 current vaccine strain (A/Hawaii/70/2019) with A/Wisconsin/588/2019 and the current H3N2 component (A/Hong Kong/45/2019) with the same one as the egg-based strain: A/Cambodia/e0826360/2020.
The influenza B strains remain the same for all vaccine types. For trivalent (three-strain) vaccines, the team recommends including the Victoria lineage.
When compared with the Southern Hemisphere recommendation made in September, the H3N2 recommendations differ for the egg and other versions.
The WHO said flu surveillance was disrupted in most countries early in the pandemic, but has since recovered, with some countries testing even more samples than in previous years. However, there were vastly fewer flu detections with fewer viruses available for sharing.
Feb 26 WHO Northern Hemisphere flu vaccine strain report
Feb 26 WHO Q and A
WHO shares more details about Russia's recent H5N8 avian flu cases
The WHO today shared more details about the seven recent human H5N8 avian flu infections reported in Russia, the first known cases involving the strain.
Russian officials detected the virus when they tested clinical specimens of poultry farm workers who took part in an H5N8 outbreak response operation in Astrakhan oblast in the south. The outbreak at the layer farm occurred from Dec 3 to Dec 11, killing 101,000 of 900,000 chickens. Given the size of the outbreak, the response took several days.
Patient ages range from 29 to 60 years, and five of them are women.
The workers who tested positive remained asymptomatic over several weeks of observation. Follow-up swab testing was negative for the virus, and serology studies suggested recent infections. No related illnesses were found in any family members or close contacts. Further serology studies in contacts are under way.
An analysis of the H5N8 virus from the poultry found that it belonged to 18.104.22.168b clade of H5 viruses, which have been detected in several European nations, including Russia, as well as Egypt and Iraq.
The WHO said more information is needed to fully assess the risk, but for now, the threat of human-to-human transmission from H5N8 remains low.
Feb 26 WHO statement
Feb 22 CIDRAP News story "Russia reports first human H5N8 avian flu cases"
Six countries report new polio cases, with some noting the first of 2021
According to the weekly update from the Global Polio Eradication Initiative (GPEI), six countries have reported new cases: Afghanistan, Pakistan, the Republic of the Congo, Ethiopia, Guinea, and Mali.
In Afghanistan, officials confirmed six circulating vaccine-derived polio type 2 (cVDPV2) cases, the first of 2021. The country tracked 305 cVDPV2 cases in 2020. Neighboring Pakistan also tracked two cVDPV2 cases bringing its 2021 total to three cases, as well as one case of wild poliovirus type 1 in Balochistan, the first of 2021.
All African nations reporting polio this week confirmed cases of cVDPV2. Congo and Ethiopia each reported one case, and Guinea noted six cases. They bring Congo's 2020 cases to 2, Ethiopia's to 25, and Guinea's to 45.
Finally, GPEI said Mali recorded 2 cases of cVDPV2 in Koulikoro, bringing its totals for last year to 38.
Feb 26 GPEI update