Malaria, other vectorborne and parasitic diseases programme

All about climate change and vectorborne diseases

All about climate change

Numerous climate change vulnerability assessments anticipate that rising global temperatures will increase the incidence of communicable diseases including vector-borne diseases (VBDs). Transmitted by bites from infected mosquitoes and other insects (vectors) VBDs are particularly dependent on climatic factors:

  • insects have no internal control over their body temperature and as ambient temperatures rise their distribution may expand through increased reproductive rate, biting behaviour and survival;
  • humidity and the availability of water for breeding also determine vector distribution, longevity and behaviour;
  • the incubation period of pathogens within vectors is also temperature-dependent and tends to become shorter in warmer conditions; and
  • human behaviour is likely to be affected by climate change which may increase our interaction with vectors and the diseases they carry.

Climate-sensitive VBDs in the Region

In the WHO Western Pacific Region, important VBDs that might be affected by climate change include malaria, dengue, other arboviruses such as Japanese encephalitis, chikungunya and West Nile virus, lymphatic filariasis, plague, tick-borne diseases including tick-borne encephalitis, Lyme disease and rickettsioses, and schistosomiasis.