Identification of malaria hot spots for focused intervention in tribal state of India: a GIS based approach

Abstract

Background: In India, presently malaria shows a declining trend whereas Plasmodium falciparum (Pf) cases show an up trend. In central India, specifically, Madhya Pradesh (M.P.) a forested and tribal area, control of malaria is logistically difficult and outbreaks are frequently recorded, reasons for this being inadequate surveillance, poor reporting, a time lag in reporting to decision makers and a lack of geo referenced information to pin point the trouble spots for a timely preventive action.

Results: An information management system based on Geographic Information System (GIS) using district and block wise malaria data, has been constructed for Madhya Pradesh for quick retrieval of info and dynamic generation of maps to highlight hot spots of malaria for formulating prompt and focused malaria control strategy. Out of total 48 districts consisting of 313 blocks, based on certain criteria GIS identified 58 blocks falling in 25 districts as Hot Spots. Malaria flares up from these pockets whenever favourable conditions for transmission occurs. It was suggested to National Vector Borne Disease Control Programme (NVBDCP) that focused malaria control in these hot pockets may be taken up on priority during the year 2007, it was implemented by State Health Authorities, M.P. under the directive of NVBDCP. Implementation of control measures were evaluated by NVBDCP.

Conclusion: GIS mapping would make it easy to update information instantly and to identify the trouble spots at the village level within the district which is the lowest unit equipped with computer facilities and the information can reach instantly to state and the policy makers to formulate focused and cost effective malaria control strategy. This is the first time when GIS has been used in national control programme for tribal malaria.

Figure 1

a) Location of Madhya Pradesh in India. b) Tribal dominated Districts in M.P. c) Tribal dominated blocks in M.P.

Figure 2

Spatio temporal evolution of malaria in 2000 – 2005 in districts of Madhya Pradesh. a) District wise Annual Parasite Incidence: number of positive cases per thousand population per year (2000 – 2005). b) District wise Pf per Cent: Per cent Pf cases out of total positive cases.

Figure 3

Spatio temporal evolution of malaria in 2000 – 2005 in blocks of Madhya Pradesh. a) Block wise Annual Parasite Incidence: number of positive cases per thousand population per year (2000 – 2005). b) Block wise Pf per Cent: Per cent Pf cases out of total positive cases.

Figure 4

Blocks satisfying conditions laid down for classifying as hot spot. a): Blocks showing 100% pf cases during 2000 – 2005. b): Blocks exhibiting consistently >30% pf during 2000 – 2005. c): Blocks reporting >70% pf in 2005. d): Districts exhibiting consistently >30% pf during 2000 – 2005.

Figure 5

Malaria hot pocket requiring focused intervention overlaid on problem districts in M.P. depicting geographic location for planning of logistics and schedule for intervention.