24 systematic reviews concerned prevention of vector-borne diseases (15 about malaria, 5 dengue fever, 2 leishmaniasis and one each Lyme disease and tick-borne encephalitis). Chemoprohylaxis (malaria 7, Lyme disease 1) and immunization (malaria 3, leishmaniasis 1, tick-borne encephalitis 1) and vector control measures (10, through reducing density of insect vectors, providing barriers between susceptible humans and vectors) were common topics for review. One review focused on culling of host species)