WHO advisers weigh in on COVID-19 boosters, Pfizer vaccine in younger kids

World Health Organization (WHO) vaccine advisers today updated their COVID-19 vaccine prioritization guidance, which backs booster shots in high-priority groups and refined their recommendations for the Pfizer/BioNTech vaccine, which it now recommends in a reduced dose for children ages 5 to 11 years.In other developments, health officials in Europe provided a snapshot of the latest Omicron variant impacts, with the United Kingdom designating the BA.2 subvariant as a variant under investigation.Most vulnerable highest priorityThe WHO's Strategic Advisory Group of Experts on Immunization (SAGE) met on Jan 19 to assess the latest vaccine developments and update their recommendations, including those relating to emergency use of the Pfizer vaccine.

Today at a briefing, they announced the third revisions to their roadmap for COVID-19 vaccine prioritization, which was first issued in October 2020.They said the main focus remains on fully protecting the most vulnerable groups, adding that booster doses should be offered to high-priority groups such as older people and healthcare workers 4 to 6 months after completing the primary vaccine series.

The interval the WHO recommends is in line with shorter intervals adopted by some countries.SAGE also emphasized that countries with high vaccine coverage in their high-risk populations should prioritize global sharing of vaccine over vaccinating healthy children and adolescents, who are at the lowest risk of severe illness.Regarding their updated assessment of the Pfizer vaccine, they recommended extending the use of the lower 10-microgram dose version to children ages 5 to 11.Tracking Omicron, watching the BA.2 subvariantIn an epidemiologic update on the Omicron variant and its