RSV Immunity Debt Produces Unintended Consequence

A recent analysis published by The Lancet Infectious Diseases revealed the long-term, hidden impact of Respiratory syncytial virus (RSV) during the COVID-19 pandemic.

Before 2019, RSV was highly seasonal in temperate countries like England.

The good news is RSV activity substantially decreased shortly after the implementation of non-pharmaceutical interventions to slow the spread of the SARS-CoV-2 coronavirus in March 2020.

However, multiple countries reported out-of-season RSV resurgences after the following winter season.

Out-of-season RSV resurgences are explained by decreased population immunity following a prolonged period of minimal RSV exposure, also referred to as RSV immunity debt.

Quantifying these effects of prolonged periods of low exposure over time is essential.

Out-of-season RSV resurgences pose significant challenges to healthcare systems already strained by two and a half years of the pandemic.

These researchers stated on September 2, 2022, 'RSV should be monitored all year round for as long as out-of-season RSV resurgences are among plausible scenarios.'

'With no specific treatment against RSV currently licensed, hospitals must ensure sufficient bed capacity to provide supportive care, notably respiratory support, during epidemics.'

'Long-lasting uncertainties about the timing of epidemics could force hospitals to maintain a high level of readiness for extended periods each year.'

'Monitoring population immunity levels should, therefore, be part of the public health toolbox.'

Overall, Bardsley and colleagues' observations confirm the concept of immunity debt as an unintended consequence of non-pharmaceutical interventions.

RSV remains the most common cause of lower respiratory tract infection in children younger than five.

In 2019, a meta-analysis estimated that RSV was associated with about 3.6 million hospitalizations annually.

As of September 6, 2022, the U.S. FDA has not authorized any RSV vaccine candidates currently conducting late-stage clinical trials, which are listed on this webpage.

There is market optimism that these innovative RSV vaccines could become available in the coming months.

Note: This article was manually translated and curated for mobile readers.