Babies in the Dutch Caribbean islands should be immunised against the RS virus earlier in the year, experts have said.

Researchers at Nijmegen’s Radboudumc medical hospital said that under the current schedule, the antibodies created in response to the jab had mostly disappeared by the time infections start to rise.

Babies are immunised against the virus in the Netherlands in September or October to protect them during the wave of infections in the autumn.

But in the Caribbean the virus begins to circulate in June, at the start of the rainy season, which runs through until December.

The RS (respiratory syncytial) virus infects the airways and causes mild illness in adults, but can be deadly or lead to severe complications for children in their first year of life.

The number of newborns in intensive care has fallen significantly since the RS virus was included in the immunisation programme last year.

The public health agency RIVM said it would look at whether to adjust the schedule in the light of the research.