Communicable Diseases and Disease Surveillance

Malaria

     National Anti Malaria Programme

Malaria is a common disease of the tropical World caused by the parasite Plasmodium. The disease is transmitted from man to man by the infective bites of female mosquitoes belonging to genus Anopheles, as the mouth parts of male mosquitoes are not developed for biting and cannot pierce the skin. There are 4 species of malaria parasites, of which 3 species are found in India. These are:

      Plasmodium Vivax that may cause relapsing malaria but seldom death (50-55% of total reported cases);

      P. falciparum that causes malignant malaria and may lead to death (48-52% of total cases) and

      P. malariae that may cause severe malaria (small numbers found in foothills in Orissa)

      P. ovale (not found in India)

Often 0.5% to 2% of P. falciparum cases (malignant variety of malaria) may develop severe malaria with complications. In such cases death rates may be 30% or more, if timely treatment is not commenced. All malaria mortality in India is due to P. falciparum only.

The disease manifests with sudden onset of high fever with rigors and sensation of extreme cold followed by feeling of burning heat, leading to profuse sweating and remission of fever by crisis thereafter. The febrile paroxysms occur every alternate day. Headache, body ache, nausea, etc. may be associated features. However in atypical cases, classical presentation may not manifest. Since infection of any kind leads to fever, the strategy adopted by NAMP is to test all fever cases for malaria in a laboratory under the microscope. This practice ensures that malaria among the fever cases are not missed, and those found positive for malaria are given full course of malaria treatment. On an average NAMP examines 80-90 million fever cases, and the current malaria incidence is about 2 million cases annually.

Malaria transmission occurs in almost all areas of India except areas above 1800 metres sea level. Country's 95% population lives in malaria risk areas. Malaria in India is unevenly distributed. In most parts of the country about 90% malaria is unstable with relatively low incidence but with a risk of increase in cases in epidemic form every 7 to 10 or more years. This depends on the immune status of the population and the breeding potential of the mosquitoes, rainfall being the leading cause of malaria epidemics as it creates high mosquito population. In North-Eastern States efficient malaria transmission is maintained during most months of the year. Intermediate level of stability of malaria transmission is maintained in the plains of India in the forests and forest fringes, predominantly tribal settlements in eight states (Andhra Pradesh, Jharkhand, Gujarat, Madhya Pradesh, Chhatisgarh, Maharashtra, Orissa and Rajasthan).

National Programme for Control of Malaria

At the time of independence malaria was responsible for an estimated 75 million cases and 0.8 million deaths annually. Government of India launched the National Malaria Control Programme (NMCP) in 1953. DDT spraying resulted in a sharp decline in malaria in all areas under spray. In 1958, GOI converted NMCP to the National malaria Eradication Programme (NMEP). The strategy of malaria eradication was highly successful and the cases were reduced to about 100,000 and deaths due to malaria were eliminated by 1965-66. Subsequently the programme faced various technical obstacles and financial and administrative constraints, which led to countrywide increase in the number of cases. 6.47 million malaria cases were reported in 1976, the highest since resurgence. In 1977 the Modified Plan of Operation (MPO) was launched with the immediate objectives to prevent deaths and to reduce morbidity due to malaria. The programme was integrated with primary health care delivery system. Selective indoor residual spray by stratifying areas based on cases per 1,000 populations in a year i.e. the Annual Parasite Incidence (API) of 2 and above was recommended in the MPO. Malaria incidence declined to about 2 million cases by the year 2000 and thereafter.

Enhanced Malaria Control Project (EMCP)

The states of Andhra Pradesh, Chattisgarh, Gujarat, Jharkhand, Madhya Pradesh, Maharashtra, Rajasthan and Orissa together contribute around 60-70% cases and deaths due to malaria. World Bank assisted Enhanced Malaria Control Project is in operation in 1045 malaria hardcore tribal PHCs of 100 districts covering 62 million population in these states. Nineteen towns of 10 States have also been included under EMCP. In these areas, attempts are being made to have an integrated strategy for malaria control which includes providing for presumptive treatment to fever cases at each village; presumptive radical treatment at health facilities in high risk areas; promotion of use of insecticide treated bed nets; use of larvivorous fish in mosquito breeding sites and selective indoor residual spray in high risk areas. The project period has been extended for a period of one year i.e. up to 31st March 2004.

Urban Malaria Scheme (UMS)

Since the resurgence of malaria in early 1970s, urban malaria has been recognised as an important problem contributing to overall malaria morbidity in the country. To assist the states in control of malaria in urban areas, Urban Malaria Scheme (UMS) was launched in 1971. The scheme is being implemented in 131 towns in the country. Urban malaria poses problems because of haphazard expansion of urban areas. The urban malaria vector, An. stephensi breeds in stored water and domestic containers. Construction activities and aggregation of labour provide ideal opportunities for vector to breed and transmit malaria in urban areas.

Under UMS, the centre provides assistance in kind which includes larvicide and 2% Pyrethrum Extract. The operational cost and the cost of MLO and equipment are borne by the states. However, the centre bears the operational cost as well as material & equipment for UMS in the North-Eastern States and Chandigarh.

Current Malaria Control Strategies

The main control strategies under the programme are:

      Early Case Detection and Prompt Treatment (EDPT) to provide relief to the patient, and reduce reservoir of the infection.

      Selective Vector Control by appropriate insecticidal spray in rural areas and recurrent anti-larval measures including biological methods like use of larvivorous fish.

      Promotion of personal prophylactic measures including use of Insecticide Treated Mosquito Nets (ITMN), etc., and promotion of bio-environmental control measures.

      Capacity building of optimal utilization of the technical manpower for the programme.

Malaria Situation

The reported incidence is between 2-3 million cases annually since 1984 with some fluctuation from year to year. The overall incidence of malaria in the country has shown a declining trend since 1987. The malaria situation in the country from 1996 onwards is given below.

*(Provisional)

**As per report received from state health authorities to the Dte. of NAMP till 25th July 03'

API: Annual Parasite Incidence (per thousand population)

The overall physical performance in respect of screening of population through active and passive surveillance of fever cases by examination of blood slides that is Annual Blood Examination Rate (ABER) has remained between 9.31 and 8.71 against the target of 10 which implies 87.1% to 93.1% achievement against target. The state-wise performance indicates that 16 states and UTs recorder ABER > 10, 10 states and UT recorded between 5-10 and 9 states recorded less ABER < 5.

77.9 million populations were covered with Indoor Residual Spray (IRS) in the country during 2001. The state-wise coverage during 2001 indicates that 21 states/UTs recorded more than 75%, eight states/UTs, 60 to 75% and 3 states less than 60% coverage against the targeted population for spray by the states/UTs. During 2002 as per provisional report 65 million population covered with IRS.

Central Assistance

NAMP is a category II centrally sponsored scheme on cost sharing basis between Centre and States. The central government provides technical guidance and assistance in the form of kind, which includes the approved materials like insecticides, anti-malarial drugs and larvicide's. Assistance is also provided for capacity building through training and IEC. The state governments are responsible for programme implementation, infrastructure and decentralized logistics. Since December 1994, NAMP has been made a 100% centrally sponsored scheme (Plan) in 7 N.E. States for meeting the operational cost in addition to material assistance for effective control of malaria. The central assistance provided to the states during the last five years is as under.

* Excluding assistance given for Kala-azar

Major Achievements

Malaria has been effectively controlled in vast areas covering almost 80% population of the country in spite of increased population, rapid and unplanned urbanization, increased migration and population aggregation. Developmental activities, industrial growth, expansion of agriculture deforestation and changing lifestyles also have the potential of increasing the breeding sites of mosquitoes. At present, malaria continues to be a public health problem affecting around 20% population that lives largely in remote, inaccessible, forest and forest-fringe areas.

These areas have poor infrastructure and large number of vacancies at key level functionary that contributes to operational difficulties in programme implementation. Further, technical obstacles like development of Chloroquine resistance in P.falciparum and insecticide resistance in malaria vectors in some areas also pose challenge to the malaria control efforts besides developmental activities leading to creation of mosquitogenic conditions, urbanization, migration and climate change serving as aggravating factors for malaria transmission.

The country has been able to contain malaria incidence between 2 and 2.5 million cases annually for more than a decade in spite of increased population @ 2.1% annually.