Flu and respiratory syncytial virus (RSV) season has just begun in the northern hemisphere, and the consensus among experts is that the 2022-2023 season is shaping up to be more severe than in recent (relatively mild) years. It might even be worse than the pre-COVID-19 seasons.
Health data company IQVIA has been analyzing insurance claims data filed by doctors’ offices, hospitals and urgent care centers across the country for three decades and has focused on case trends over the of the previous year. The team found that flu diagnoses were already at record highs. Even before the start of the flu season in the spring of 2022, influenza cases began to be well above the three-year average, reaching almost 950,000 cases per week by mid-October ( compared to around 400,000 at the same period in 2019, just before the pandemic). began).
These higher rates are not completely unexpected. Flu cases dropped significantly in the first two years of the pandemic, when people had less contact with each other and generally followed mitigating measures to control COVID-19, such as wearing masks and social distancing. These behaviors helped stop the spread of the flu. But, says Murray Aitken, executive director of the IQVIA Institute, current flu numbers “trend to increase each year since 2012 significantly.”
Experts are also concerned about another worrying flu trend. The Southern Hemisphere flu season, which often gives the United States a glimpse of what to expect, hit early and hard this year. Australia, for example, had its worst flu season in five years, with nearly 30,000 lab-confirmed flu cases at its weekly peak in June; flu season tends to peak later, between July and September.
Other respiratory viruses, SARS-CoV-2 and RSV, are also on the rise. COVID-19 is still responsible for about 260,000 infections per week in the United States on average, and labs that are part of the U.S. Centers for Disease Control and Prevention’s National Respiratory and Enteric Virus Surveillance System have reported a 500% increase in the percentage of positive tests. for the RSV from the beginning of September. RSV affects children and the elderly the hardest. “This virus is hitting extremely hard this year,” says Dr. Juanita Mora, spokesperson for the American Lung Association and allergist and immunologist at the Chicago Allergy Center. One of the reasons cases are rising so quickly (especially in young children), and so early in the season, could be because COVID-19 restrictions that have closed schools and kept children at home have protected many of them against any infection during the last two years. . “In general, 100% of children will have had RSV by the age of two, but that’s not the case now,” Mora says. “For the last three years we haven’t had an RSV season, so we have a cohort of children who don’t have the immunity that they might normally have.”
Although there is a vaccine to protect children against RSV, it is only approved for children most at risk of developing serious disease, such as premature babies and those born with lung or heart disease. The vaccine requires monthly injections throughout the infection season, and most children are not eligible to be vaccinated. For them, Mora says, the best protections are the same behaviors that protect children from the flu and COVID-19: keeping children informed about flu and COVID-19 vaccines, washing their hands often and avoiding everything. close contact with coughing children. or sneezing.
With flu and RSV cases rising so rapidly, hospitals in some parts of the country are already feeling strained. But the situation could worsen as new variants of COVID-19, some of which evade vaccine protections, continue to proliferate this winter.
What is contributing to the rapid and historic increase in respiratory disease? This is likely a combination of factors, including mild seasons early in the pandemic as well as slow flu vaccination rates. Although it is still relatively early in the flu season, flu vaccination is almost 9% behind what it normally is now during the pre-pandemic years.
Experts say that while these signs are concerning, the United States is not necessarily doomed to suffer as severe a virus season as countries like Australia. If more people get vaccinated against influenza and COVID-19, it could lessen the effects of viruses that are circulating more strongly than usual.
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