Netherlands sees slight decrease in Meningococcus W infections

The number of infections with Meningococcus type W bacteria in the Netherlands is declining slightly, according to new figures from public health institute RIVM. The decrease can only partly be attributed by the new vaccination program for this bacteria among teenagers, Hans van Vliet, head of the RIVM's National Vaccination Program, said to NOS.

Meningococcus W is more often fatal than other types of Meningococci bacteria. It can cause blood poisoning and meningitis, which can turn fatal within 24 hours of infection. The RIVM therefore launched a national vaccination program for teenagers between 14 and 18 years last year, as they play a major role in the spread of this bacteria. The vaccination covers four types of Meningococci, including type W.

But according to Van Vliet, the vaccination is likely not the main cause of the decline in infections. "A very small part, but we do not expect the real effect of it until after a longer period of time", he said to NOS. "It seems like a natural development. Just as we could not explain the increase in type W infections since 2015, we can not explain this either."

Before 2015, an average of four people became infected with type W in the Netherlands per year. Last year there were 103 type W infections. Up to and including June this year, 39 type W infections were reported. Since 2015, a total of 45 people in the Netherlands died from a type W infection, 23 of which last year. So far this year, five people have died. The risk of death is particularly high in the age group 14 to 24 years, according to the RIVM.

The decline in infections is reason enough to be cautiously optimistic, Van Vliet said to NOS. "But it is not yet a guarantee. Because the behavior of the bacteria remains difficult to predict", he said. Not much is known about type W yet. "But the entire vaccination campaign is accompanied by all sorts of studies."