Concepts required to understand the epidemiology and ecology of vector-borne diseases are presented in sections that cover components of the transmission cycle, modes of transmission by the vector, different types of transmission cycles based on vertebrate hosts, vector incrimination, interseasonal maintenance mechanisms, and surveillance. Minimal components required for transmission of a vector-borne pathogen include a competent vertebrate host and an arthropod vector, a virulent pathogen, and a suitable environment. The efficiency of transmission depends on the frequency of contact between host and vector and is delineated by blood meal acquisition behavior by the vector and environmental conditions that drive the system. Transmission cycles mostly have evolved from sylvan zoonoses comprised of a diverse variety of hosts and vectors to urbanized anthroponoses comprised of human hosts and a limited number of vectors that frequently rest and blood feed in houses. Vector incrimination is dependent upon the diagnosis of frequent field infection, degree of competent host contact, and vector competence determined experimentally. Many vector-borne pathogens appear to have evolved in the tropics, but have become a serious public, veterinary, or wildlife health problem after invading temperate latitudes. Here, interseasonal maintenance becomes a key element for pathogen persistence, delineates endemicity, and delimits distribution in time and space. Because outbreaks of vector-borne disease occur intermittently even in endemic areas, surveillance programs are required to track cases and the pathogen within transmission cycles in time and space to inform public health policy and provide operational decision support to direct intervention.
- Transmission cycles
- Vector incrimination
- Vectorial capacity
ASJC Scopus subject areas
- Immunology and Microbiology(all)
- Agricultural and Biological Sciences(all)