Vector-Borne Diseases

There has been a worldwide resurgence of vector-borne diseases since the 1970s including malaria, dengue, Yellow fever, louse-borne typhus, plague, leishmaniasis, sleeping sickness, West Nile encephalitis, Lyme disease, Japanese encephalitis, Rift Valley fever, and Crimean-Congo hemorrhagic fever. Reasons for the emergence or resurgence of vector-borne diseases include the development of insecticide and drug resistance; decreased resources for surveillance, prevention and control of vectorborne diseases; deterioration of the public health infrastructure required to deal with these diseases; unprecedented population growth; uncontrolled urbanization; changes in agricultural practices; deforestation; and increased travel. Changes have been documented in the distribution of important arthropod disease vectors. The yellow fever mosquito, Aedes aegypti has reestablished in parts of the Americas where it had been presumed to have been eradicated; the Asian tiger mosquito, Aedes albopictus, was introduced into the Americas in the 1980s and has spread to Central and South America; and the blacklegged tick, Ixodes scapularis, an important transmitter of Lyme disease and other pathogens, has gradually expanded its range in parts of eastern and central North America.