Experts predict ‘twindemic’ with surging cases of influenza and RSV

by Jacob Fuller

Lauren Dempsey, MS in Biomedicine and Law, RN, FISM News 


Doctors and other disease experts are sounding the alarm about a “twindemic” of influenza and respiratory syncytial virus (RSV), which could be particularly dangerous for children.

Many of the same experts, however, previously predicted that a simultaneous surge in COVID-19 and flu cases over the last two winters would create a “twindemic,” but their predictions never became reality.

Some suggest that COVID-19 public health measures and mitigation strategies kept the flu and RSV from circulating. Now that the country has relaxed restrictions, some fear that this winter people could be much sicker.

However, the 2022-2023 flu season was significantly worse than previous years in countries like Australia and recent data from the CDC suggests that flu season in the United States is starting earlier and will likely be rougher than typically expected. This trend is also being seen in the United Kingdom. The most recent CDC surveillance report shows that positive flu cases increased from 1,274, or 2.2%, to 1,766, or 3.3%, of specimens that were collected with almost 96% being Influenza type A.

Cases of RSV usually appear in November and the season lasts until April, whereas the flu season starts in October and ends in May.

Hospitals are reporting higher than usual cases of RSV occurring much earlier in the season than is normally seen. Monica Buchanan, senior director of strategic and enterprise communications for Connecticut Children’s Hospital told CNN “RSV admissions have skyrocketed at Connecticut Children’s,” adding that, “October has been like never before for this virus.”

The hospital’s executive vice president Dr. Juan Salazar added: “I’ve been doing this for a long time, I’ve been at Connecticut Children’s for 25 years, and I have never seen this level of surge – specifically of RSV – coming into our hospital.” He also said that during the COVID-19 pandemic children lacked exposure to other viruses which may have weakened their immune systems.

The lockdowns and isolation strategies to prevent COVID-19 seemed to have a rebound effect with hospitals reporting that more children were being hospitalized for common illnesses such as rhinoviruses and adenoviruses over the summer. Rachel Baker, a researcher at Princeton University warned that “The numbers [of infections] were pretty stable for 30 years, but in 2020 it disappeared. We need to be aware that future large outbreaks might be coming.”

The CDC reports an increase in RSV detections and RSV-associated emergency department visits and hospitalizations across the U.S. with some regions already reaching peak levels of infection. In an average year, there are about 2.1 million outpatient visits for RSV among children younger than 5 years old, 58,000 hospitalizations, and 100–300 deaths.

Adults can also get RSV, but the virus typically presents as a common cold, with many recovering within a week or two. Children — especially infants — have smaller airways, which puts them at risk for more severe respiratory infections like bronchiolitis and pneumonia that may require hospitalization.

Treatment for RSV is limited to symptom management and supplemental oxygenation when needed. There is no vaccine or antiviral medication currently available, although researchers are working on it. Dr. Francesca Ceddia, senior vice president of respiratory vaccines at Moderna, told Pharmacy Times that the company is in the early stages of developing a combined mRNA vaccine for influenza, COVID-19, and RSV.