Malaria

Malaria is a potentially life-threatening parasitic disease caused by parasites known as Plasmodium viviax (P.vivax), Plasmodium falciparum (P.falciparum), Plasmodium malariae (P.malariae), and Plasmodium ovale (P.ovale). It is transmitted by the infective bite of the Anopheles mosquito. Man develops disease after 10 to 14 days of being bitten by an infective mosquito. There are two types of parasites of human malaria, Plasmodium vivax, and P. falciparum, which are commonly reported in the state of Himachal Pradesh. Inside the human host, the parasite undergoes a series of changes as part of its complex life cycle. (Plasmodium is a protozoan parasite). The parasite completes its life cycle in liver cells (pre-erythrocytic schizogony) and red blood cells (erythrocytic schizogony )Infection with P.falciparum is the most deadly form of malaria.

The epidemiological scenario of the malaria situation in the state of Himachal Pradesh from 1981 to 2021

VECTORS OF MALARIA

• There are many vectors of malaria
• Anopheles culicifacies is the main vector of malaria
• It is a small to a medium-sized mosquito with Culex like sitting posture

1 Feeding Habits

• It is a zoophilic species
• When high densities build up relatively large numbers feed on men

2 Resting habits

• Rests during daytime in human dwellings and cattle sheds

3 Breeding places

• Breeds in rainwater pools and puddles, borrow pits, river bed pools, irrigation channels, seepages, rice fields, wells, pond margins, and sluggish streams with sandy margins.
• Extensive breeding is generally encountered following monsoon rains.

4 Biting time

• The biting time of each vector species is determined by its generic character, but can be readily influenced by environmental conditions.
• Most of the vectors, including Anopheles culicifacies, start biting soon after dusk. Therefore, biting starts much earlier in winter than in summer but the peak time varies from species to species.

MALARIA CONTROL STRATEGIES

1. Early case Detection and Prompt Treatment (EDPT)

• EDPT is the main strategy for malaria control - radical treatment is necessary for all the cases of malaria to prevent transmission of malaria.
• Chloroquine is the main anti-malaria drug for uncomplicated malaria.
• Alternative drugs for chloroquine resistant malaria are recommended as per the drug policy of malaria.

2. Vector Control

(i) Chemical Control

• Use of Indoor Residual Spray (IRS) with insecticides recommended under the programnme
• Use of chemical larvicides like Abate in potable water
• Aerosol space spray during daytime
• Malathion fogging during outbreaks

(ii) Biological Control

• Use of larvivorous fish in ornamental tanks, fountains, etc.
• Use of biocides.

(iii) Personal Prophylactic Measures that individuals/communities can take-up

• Use of mosquito repellent creams, liquids, coils, mats, etc.
• Screening of the houses with wire mesh
• Use of bednets treated with insecticide
• Wearing clothes that cover a maximum surface area of the body

4. Community Participation

• Sensitizing and involving the community for detection of Anopheles breeding places and their elimination
• NGO schemes involving them in programme strategies
• Collaboration with CII/ASSOCHAM/FICCI

5. Environmental Management & Source Reduction Methods

• Source reduction i.e. filling of the breeding places
• Proper covering of stored water
• Channelization of breeding source

6. Monitoring and Evaluation of the programme

• Monthly Computerized Management Information System(CMIS)
• Field visits by state by State National Programme Officers
• Field visits by Malaria Research Centres and other ICMR Institutes
• Feedback to states on field observations for correction actions.

Targets for Malaria Elimination in Himachal Pradesh: -

Himachal Pradesh is currently in Category 1 i.e. Elimination Phase. In districts where transmission is interrupted, the goal is to maintain malaria-free status and prevent re-introduction, with particular emphasis on tackling the problem associated with imported malaria.