Bloodsucking insects and ticks can transmit pathogens between animals, between humans and between animals and humans. The vector-borne infections which affect humans represent a complex relationship between three different types of organism: human, vector and pathogen. Examples include malaria, dengue fever and chikungunya (CHIKV). Vector-borne zoonotic diseases, transmitted between animals and humans via insect bites, represent an even more complex situation. Vertebrates play a very important role in the epidemiology of diseases such as Lyme Disease and West Nile Fever, which can have both mammals and birds as the intermediary host.
Lyme Disease has been the subject of much attention in the Netherlands. This is because it is the only endemic vector-borne disease which affects humans. RIVM research reveals that the number of reported tick bites has risen in recent decades, as has that of cases of Erythema Migrans, the rash that typifies Lyme Disease. We are performing further research to gain a better understanding of why this should be so, and to formulate an appropriate response. Our research focuses on the extent of the public health problem, the pathogens which cause infection and the seriousness of the resultant illness. We devote particular attention to the complex transmission cycle from animal via vector to human. Another research programme is concerned with ways in which diagnostic testing for Lyme Disease can be improved. RIVM has also produced resources to support public health education about Lyme Disease.
In recent years, the Asian tiger mosquito has also attracted considerable attention. Although an ‘exotic’ species (i.e. not native to the Netherlands), the Asian tiger mosquito has regularly been found in glasshouses and among stockpiles of used tyres. RIVM is monitoring the risks to public health should this species establish a permanent presence in the Netherlands. We also coordinate the development of policy and an intervention plan for the eradication of exotic mosquitoes, whereby attention must be devoted to the risks which the use of biocides may pose to public health and the environment.
RIVM is also actively involved in the development of an early warning system for possible outbreaks of vector-borne diseases in other parts of the world, in partnership with the ECDC and other European health organisations.