RS vaccine leads to sharp drop in infant ICU admissions this winter

The number of babies requiring intensive care due to an RS virus infection has dropped sharply this fall and winter, the Rijksinstituut voor Volksgezondheid en Milieu (RIVM) reports. Between late September and early February, 43 infants were admitted to the ICU with RS, whereas 178 were hospitalized in the same months last year. The 75 percent decrease is mainly the result of the rollout of the RS vaccine, according to the institute.

Infants became eligible for a vaccine against the virus at the beginning last fall. The vaccines offers protection for approximately half a year. In recent months, around 75 percent of babies have been immunized, the RIVM reports. Further research in the months ahead will determine the exact impact of the vaccination.

A year ago, the large number of young children hospitalized with the RS virus strained planned pediatric intensive care services. The virus can lead to serious respiratory infections and poses the greatest risk to the youngest infants.

Rather than prompting the body to generate its own antibodies, as a conventional vaccine does, the RS injection works through passive immunization. It delivers preformed antibodies, nirsevimab, that offer instant protection against the virus.

Since the antibodies circulate in the blood right away, infants gain protection nearly instantly after the injection. That protection remains effective for roughly half a year, typically long enough to cover the winter months, with the virus most prevalent between October and March.

Beyond intensive care cases, between 1,500 and 3,000 infants in the Netherlands are typically admitted to hospital each RS season due to RSV, the RIVM reports. Early findings from Spain and France suggest that the RS vaccination could cut overall hospitalizations by roughly three-quarters to four-fifths.