With a relatively large COVID-19 outbreak expected in the United States over the summer, the Food and Drug Administration is considering approving a COVID-19 vaccine that combines this year’s strain as early as this week, CNN reported, citing anonymous people familiar with the matter.
Last year, the FDA authorized a COVID vaccination for 2023-2024 on September 11, near the peak of SARS-CoV-2 infections during that year’s summer epidemic. This year, the summer epidemic started earlier and, by some indicators, peak levels are much higher than usual.
Detection of SARS-CoV-2 in wastewater currently indicates “very high” virus levels in 32 states and the District of Columbia. An additional 11 states are listed as “high.” Looking at the trends, areas in the southern and western parts of the country are now reporting SARS-CoV-2 levels in wastewater comparable to the 2022-2023 and 2023-2024 winter waves, which peaked in late December.
SARS-CoV-2 concentrations in wastewater by state
Trends in SARS-CoV-2 concentrations in wastewater by region over the past year
Trends in SARS-CoV-2 concentrations in wastewater by region throughout the pandemic
The test positivity rate, a metric that has fallen due to a dramatic decline in testing, stood at 18.1% weekly test positivity (approximately 43,000 tests) in mid-August. If this accurately reflects the number of cases, such a rate would not have been seen since the peak of 30.5% during the first surge in the Omicron wave in January 2022 (approximately 991,000 tests).
The good news is that we have accumulated so much protection from past infections and vaccinations that the two most serious indicators — emergency department visits and deaths — have not shown similar increases. The weekly percentage of emergency department visits diagnosed with COVID-19 is low, similar to last summer’s outbreak. The death toll is similarly low, but this is only a provisional figure from the most recent weeks.
The FDA is firmly committed to a strategy of offering an annual COVID-19 vaccine for the winter epidemic rather than the summer epidemic. The FDA’s idea is to encourage Americans to get the flu and COVID-19 vaccines together between September and November, just before the cold-weather respiratory illnesses occur simultaneously. The new vaccination ramp-up could blunt the level of severe respiratory illness at a time when the health care system is at highest risk of being overwhelmed.
Seasonality
But whereas seasonal influenza and other respiratory viruses almost exclusively surge in the winter, COVID-19 seasonality was not a given, and so far, summer waves have occurred just as consistently as winter waves, creating some hiccups in vaccine releases.
Some experts are urging people to get the COVID-19 vaccine in preparation for a summer surge in cases. “Now is the time to get vaccinated as cases surge,” Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told CNN on Sunday.
However, the only vaccines currently available target last year’s strains (related to the XBB.1.5 Omicron variant), which are already gone and may not offer strong protection against current strains (JN.1 and KP.2 Omicron variants). Even if a vaccine targeting the 2024-2025 KP.2 is approved by the FDA this week and hits pharmacy shelves next week, it will take two weeks for a single dose to provide full protection. By that time, the summer epidemic will likely have waned. In fact, some regions, including parts of the South and West, appear to have already peaked.
Another thing to consider is the timing for maximum protection from winter epidemics. Last year, the CDC recommended only one dose of the vaccine for healthy people aged 5 years and older. This shot provides maximum protection for about four months. Getting your annual shot in early September could result in less protection if COVID-19 peaks again at the end of the year, as it has done the past two years.
As per the 2023-2024 guidelines, people aged 65 and above can get a second COVID-19 booster shot four months after the first dose. People who are moderately or severely immunocompromised can also get a booster dose of the updated COVID-19 vaccine.
