Booster injections are extremely effective at preventing hospitalisations for coronavirus, says Dutch public health institute RIVM, after studying hospital figures over a two month period.

However, the results may now be different because the research focused mainly on the Delta variant of the virus, while more infectious Omicron is now dominant in the Netherlands.

The RIVM researchers said someone who had a booster had a five times lower chance of being admitted to hospital than someone who has been vaccinated, but not yet a third jab.

In the period November 10 to January 13, the protection rate for people with a booster was 97% against a hospital admission, and 98% against ending up in an intensive care ward. For those without the booster, the rates were 85% and 93%, the RIVM said.

The chance of someone who was fully vaccinated, including booster, being admitted to hospital was 33 times lower than that of someone who had not been vaccinated at all.

The vaccine effectiveness of booster vaccination will be monitored in the next few months to track effectiveness in relation to the Omicron variant and how it develops, the RIVM said.

The RIVM said that data from Britain indicates that the basic series of vaccinations as well as the booster offers less protection against the Omicron variant than against Delta, but that a booster vaccination still provides much more protection against Omicron than the basic vaccinations on their own.

According to the government’s coronavirus dashboard, some 53% of the over 18s have had a booster injection so far. This week the government launched a new publicity campaign in an effort to improve the take up rate.