Context:

The National Vector Borne Disease Control Programme (NVBDCP) is a comprehensive programme for prevention and control of vector borne diseases namely Malaria, Filaria, Kala-azar, Japanese Encephalitis (JE), Dengue and Chikungunya which is covered under the overall umbrella of NRHM. Directorate of National Vector Borne Disease Control Programme (NVBDCP) is the central nodal agency for the prevention and control of vector borne diseases.

Malaria

• Malaria is a complex mosquito-borne infectious disease caused by a eukaryotic protist of the genus Plasmodium. It varies widely in epidemiology and clinical manifestation in different parts of the world. In India, Malaria is caused by Plasmodium falciparum or Plasmodium vivaxtransmitted by nine major species of anopheline mosquitoes.
• Malaria continues to pose a major public health threat in different parts of the country, particularly due to Plasmodium falciparium as it is sometimes prone to complications and death, if not treated early.
• The major vector mosquito for rural malaria viz. Anophales culicifacies, is distributed all over the country and breeds in clean ground water collections. Some of the vector species also breed in forest areas, mangroves, lagoons, etc., even in those with organic pollutants.
• About 80% of malaria burden is in North-eastern (NE) states, Chhattisgarh, Jharkhand, Madhya Pradesh, Odisha, Andhra Pradesh, Maharashtra, Gujarat, Rajasthan, West Bengal and Karnataka.
• The focus is on empowering grass-root workers in diagnosing and treating malaria cases even in remote and accessible areas by scaling-up the availability of bivalent Rapid Diagnostic Kits (RDK) and Artemisinin-based Combination Therapy (ACT).
• There is a need to give thrust for prevention/control of malaria (and other VBD also) in urban areas under the Urban Malaria Scheme which is presently implemented in only 131 towns/cities. These efforts coupled with integrated vector control strategies including distribution of Long Lasting Insecticide Treated Nets (LLIN) in endemic areas will greatly reduce the malaria morbidity and mortality.
• Bi-valant Rapid Diagnostic Kit for improving diagnostic facilities for both types of malaria (Plasmodium Falciparum and Plasmodium Vivax) in difficult and inaccessible areas have been introduced in the programme.
• Performance based incentive for ASHAs in endemic areas for Malaria and Kala azar has been introduced in India.

Filariasis

• Filariasis is transmitted by mosquito species i.e. Culex quinquefasciatus and Mansonia annulifera/M. uniformis. The vector mosquitoes breed in polluted water in drains, cross pits etc. in areas with inadequate drainage and sanitation.
• The target year for Global elimination of this disease is by the year 2020. Government of India is signatory to the World Health Assembly Resolution in 1997 for Global Elimination of Lymphatic Filariasis. The National Health Policy (2002) has however, envisaged elimination of lymphatic filariasis in India by 2015.
• The strategy of annual Mass Drug Administration (MDA) with annual single recommended dose of DEC + Albendazole tablets is being implemented in the country since 2004. In addition, scaling up of home based foot care and hydrocele operation have been initiated for disability alleviation.

Kala-Azar

• Kala-azar is caused by a protozoan parasite Leishmania donovani and spread by sandfly, which breeds in shady, damp and warm places in cracks and crevices in the soft soil, in masonry and rubble heaps, etc.
• Important recent initiatives taken to control Kala-azar include case detection through rapid diagnostic kits and improved treatment compliance by using oral drug Miltefosine.
• In addition, compensation to the patients for loss of wages and incentive to ASHAs/volunteers for case detection and ensuring complete treatment have also been provided.

Japanese Encephalitis

• Japanese Encephalitis is a zoonotic disease which is transmitted by vector mosquito mainly belonging to Culex vishnui group. The transmission cycle is maintained in the nature by animal reservoirs of JE virus like pigs and water birds. Man is the dead end host, i.e. JE is not transmitted from one infected person to other.
• Outbreaks are common in those areas where there is close interaction between animals/birds and human beings. The vectors of JE breed in large water bodies such as paddy fields.
• AES is emerging as a serious public health challenge. Given its complex etiology, medical complications and after-effects of illness, effort is on to develop a multi-pronged strategy including safe water, sanitation, nutrition, community education, medical attention and rehabilitation to address the problem.
• The disease is endemic in 14 states of which Assam, Bihar, Haryana, and Uttar Pradesh have been reporting outbreaks.

Dengue Fever

• Dengue Fever is an outbreak prone viral disease, transmitted by Aedes Aegypti mosquitoes.
• Aedes aegypti mosquitoes prefer to breed in man made containers, viz., cement tanks, overhead tanks, underground tanks, tyres, desert coolers, pitchers, discarded containers, junk materials, etc. in which water stagnates for more than a week. This is a day biting mosquito and prefers to rest in hard to find dark areas inside the houses.
• The risk of dengue has shown an increase in recent years due to rapid urbanization.
• The disease has a seasonal pattern i.e. the cases peak after monsoon and it is not uniformly distributed throughout the year.
• Dengue is a self limiting acute disease characterized by fever, headache, muscle, joint pains, rash, nausea and vomiting. Some infections result in Dengue Haemorrhagic Fever (DHF) and in its severe from Dengue Shock Syndrome (DSS) can threaten the patient’s life primarily through increased vascular permeability and shock due to bleeding from internal organs.

Chikungunya

• Chikungunya is a debilitating non-fatal viral illness caused by Chikungunya virus which has re-emerged in the country after a gap of three decades.
• This disease is also transmitted by Aedes mosquito. Both Ae. aegypti and Ae. albopictus can transmit the disease.
• Humans are considered to be the major source or reservoir of Chikungunya virus. Therefore, the mosquitoes usually transmit the disease by biting infected persons and then biting others. The infected person cannot spread the infection directly to other person (i.e. it is not a contagious disease).
• Improved surveillance, case management and community participation, inter-sectoral collaboration, enactment and enforcement of civic bye laws and building bye laws are emphasized for this diseases.

Source: nvbdcp.gov.in