Mosquito
Mosquito-borne diseases are currently most prevalent in East Africa, Latin America,  Southeast Asia, and India; however, emergence of vector-borne diseases in Europe have recently been observed. A weighted risk analysis demonstrated associations to climate for 49% of infectious diseases in Europe including all transmission routes. One statistical model predicts by 2030, the climate of southern Great Britain will be climatically-suitable for malaria transmission "Plasmodium vivax" malaria for 2 months of the year. By 2080 it is predicted that the same will be true for southern Scotland.
Dengue fever outbreaks
The first recognized dengue epidemics occurred almost simultaneously in Asia, Africa, and North America in the 1780s, shortly after the identification and naming of the disease in 1779. A pandemic began in Southeast Asia in the 1950s, and by 1975 DHF had become a leading cause of death among children in the region. The first case of DHF was reported in Manila, Philippines around 1953 through 1954. A small child with dengue fever started to bleed uncontrollably. Other children then became victims to the new symptom. Epidemic dengue has become more common since the 1980s. By the late 1990s, dengue was the most important mosquito-borne disease affecting humans after malaria, with around 40 million cases of dengue fever and several hundred thousand cases of dengue hemorrhagic fever each year.
Significant outbreaks of dengue fever tend to occur every five or six months. The cyclical rise and fall in numbers of dengue cases is thought to be the result of seasonal cycles interacting with a short-lived cross-immunity for all four strains in people who have had dengue. When the cross-immunity wears off the population is more susceptible to transmission whenever the next seasonal peak occurs. Thus over time there remain large numbers of susceptible people in affected populations despite previous outbreaks due to the four different serotypes of dengue virus and the presence of unexposed individuals from childbirth or immigration.