Healthcare leaders are closely watching respiratory virus trends heading into fall. Overall, there is a healthy dose of optimism that the U.S. won't see the same levels of severe disease that strained hospitals nationwide last year, though it's still too early to determine whether a "tripledemic" of COVID-19, flu and respiratory syncytial virus will play out in some capacity.
In early September, life sciences analytics company Airfinity released forecasts indicating U.S. hospitalizations for the viruses will peak at the end of January.
For now, here's a look at where things currently stand with COVID-19, flu and RSV:
COVID-19: Both hospitalizations and deaths continue to climb, according to the CDC's most recent data. There were 18,971 new COVID-19 admissions for the week ending Sept. 2, marking a nearly 9 percent increase from the week prior. Deaths were also up 10.5 percent. COVID-19 admissions have increased for eight consecutive weeks in the U.S. While COVID-19 metrics are rising again, admissions are increasing from record lows. For context, in 2022, there were 34,546 new admissions for the same week, and in 2021, they were at 84,235, according to CDC's historical data.
The emergence of new, more mutated subvariants like BA.2.86 is important to watch, but the strain has not yet shown it is infectious enough to outcompete the current dominant strains like EG.5, according to lab data. Subvariant FL.1.5.1 however, was found to be the most immune-evasive XBB relative. The updated COVID-19 shots, which the FDA approved Sept. 11, are expected to protect against some of the newer strains.
With admissions and deaths both increasing and newer variants emerging, some hospitals and health systems have brought back mask policies. Others are watching trends and waiting to make that determination.
Flu: Overall, flu activity remains low across the country, though the CDC anticipates levels to increase over the next few weeks. Fewer than 1 percent of specimens tested at clinical laboratories across the nation tested positive for influenza for the week ending Sept. 2, CDC data shows. According to recent data, the flu vaccine in the Southern Hemisphere reduced the risk of influenza-associated hospitalizations by 52 percent, indicating flu shots in the U.S. will offer similar levels of protection. Experts typically monitor trends in the Southern Hemisphere, where flu season is now winding down, to predict how things could play out in the U.S. Australia saw large numbers of cases, with disease rates highest in children, which may be due to a decrease in pediatric vaccination rates compared to previous years, health experts told Becker's.
Last year, the U.S. saw an early and severe start to flu season, with activity beginning to increase in early October and peaking in early December. Overall, estimates indicate around 300,000 people in the U.S. were hospitalized with the flu last season. Typically, flu season peaks later, between December and February. The CDC typically recommends people 6 months and older get an annual flu vaccine.
RSV: After COVID-19 related disruptions last year, experts largely anticipate RSV to follow a more typical seasonal pattern this year, with activity ramping up in the fall and peaking in December or January. On Sept. 5, the CDC issued a health alert saying RSV activity was increasing in the Southeast, suggesting the U.S. will see a national uptick within several months. RSV began an unseasonably early ascent last summer. By October, an intense surge was overwhelming children's hospitals nationwide. Many experts believe RSV came back with a vengeance in the 2022-23 season because many people weren't exposed during the prior season, when masking and other COVID-19 prevention measures were still commonplace.
Experts are optimistic the intensity this year will be "closer to normal" in line with pre-pandemic patterns, given the virus's prevalence last season. This year also marks the first time RSV vaccines will be available to adults 60 and older, a group that is at high risk of severe disease. A monoclonal antibody will also be available for infants.