While it seems a while off, as we take in the lazy days of summer, respiratory viral season is just around the corner. Scientists have been hard at work trying to prepare and also to ensure that the coming fall and winter don’t see a repeat of last year’s so-called tripledemic.
While the start of the school year and cooling temperatures often lead to a broad range of viral respiratory illnesses, these days the big three are flu, RSV and COVID-19. During the 2022-23 viral season, a surge in cases resulting from all three of these potent viruses had the combined effect of increased hospitalizations and deaths, especially among the most vulnerable people with weakened immune systems and the elderly.
Seasonal flu is caused by the influenza virus, which has long been a source of illness during the colder months whereas COVID-19 is caused the SARS-CoV-2 virus, which was first identified in late 2019. RSV, also known as respiratory syncytial virus, is well known to pediatricians as a virus that affects young children but it also can cause serious illness among older people and those with immunocompromising conditions.
There are multiple strains of each of these viruses, resulting from mutations that are constantly occurring. For this reason, people who have been vaccinated during a previous season and even those who have recovered from an infection can get infected again, especially during a future season. Respiratory viral season typically runs from October to April but can sometimes start early and/or end late.
Vaccination is one of the most effective ways to reduce the risk of serious illness from flu, COVID-19 and now even RSV (among older people).
Each year, scientists reformulate the flu vaccine to contain the strains of influenza virus most likely to be circulating during the flu season. A decision is typically made during the spring to allow adequate time for vaccine production to permit late summer vaccinations.
Last month, the U.S. Food and Drug Administration also announced the vaccine formula for this year’s COVID-19 vaccine, which will likely be available at the same time as the flu vaccine. The chosen strain is XBB.1.5, which is among the most common strains of SARS-CoV-2 currently circulating. It is likely that a universal COVID-19 vaccine will be recommended similar to flu vaccine in the years to come.
You may have heard that the FDA also recently approved two RSV vaccines that will be offered to people ages 60 years and older later this year. The goal is to reduce the risk of hospitalization and death from RSV among the elderly.
Last year flu, COVID-19 and RSV combined were responsible for more than 100,000 deaths in the United States during the fall and winter. Many of these deaths and many more hospitalizations could have been prevented with vaccination for flu and COVID-19. This year, most people will have access to a recommended flu and COVID-19 vaccine and people 60 and older will also have the option of an RSV vaccine.
Dr. Matthew A. Clark, a board-certified physician in internal medicine and pediatrics, works for the Indian Health Service.
