Vector-borne diseases

The national capital of Delhi and the two Telugu States have been witnessing a steep rise in dengue fever amid fear of a possible outbreak as the total number of cases from the vector-borne disease is rising alarmingly.

Vectors are organisms that transmit pathogens and parasites from one infected person (or animal) to another, causing serious diseases in human populations. These diseases are commonly found in tropical and sub-tropical regions and places where access to safe drinking-water and sanitation systems is problematic.

Vector-borne diseases account for 17% of the estimated global burden of all infectious diseases. The most deadly vector-borne disease, malaria, caused an estimated 627 000 deaths in 2012. However, the world's fastest growing vector-borne disease is dengue, with a 30-fold increase in disease incidence over the last 50 years.

Vector-borne diseases are infections transmitted by the bite of infected arthropod species, such as mosquitoes, ticks, triatomine bugs, sandflies, and blackflies. Arthropod vectors are cold-blooded (ectothermic) and thus especially sensitive to climatic factors.

Weather influences survival and reproduction rates of vectors2, in turn influencing habitat suitability, distribution and abundance; intensity and temporal pattern of vector activity (particularly biting rates) throughout the year; and rates of development, survival and reproduction of pathogens within vectors.

However, climate is only one of many factors influencing vector distribution, such as habitat destruction, land use, pesticide application, and host density, according to European Centre for Disease Prevention and Control Vector-borne infectious diseases, such as malaria, dengue fever, yellow fever, and plague, cause a significant fraction of the global infectious disease burden; indeed, nearly half of the world’s population is infected with at least one type of vector-borne pathogen.

The National Vector Borne Disease Control Programme of India (NVBDCP) is the programme for prevention & control of these vector borne diseases as an integral part of the National Rural Health Mission (NRHM) of India. The NVBDCP envisages a self-sustained and well informed, healthy India free from vector borne diseases with equitable access to quality health care services nearest to their residences.

The programme activities are directed in a way to meet with the Millennium Development Goal of halting and reversing the incidence of malaria and other vector borne diseases by the year 2015 towards reduction of poverty.