In the span of two decades, Tamil Nadu wrestled with malaria, and within that period, the State managed some modest victory over the disease. From over a lakh cases in the 1990’s, and a significant percentage of them in the urban Chennai area, today, the State has whittled down its malaria positive cases substantially, and achieved an even better record of reducing deaths from malaria.
Considered an urban problem brought on by migration, rapid industrialisation, and hectic construction activity, aided by helpful monsoons in a tropical zone, malaria was the big bug bear of the State’s public health system. A systematic campaign of surveillance, prevention and vector control, and aggressive screening and treatment are some of the reasons for the achievements over the years, epidemiologists point out, on the occasion of World Malaria Day on Thursday.
“Over the years, the number of cases has come down significantly,” says S. Elango, former Director of Public Health. The reduction was not drastic, but very gradual and a result of some intensive awareness campaign, and a multi-modal approach, he adds.
He points out that the most remarkable achievement has been in the Chennai Corporation area, which at some point, accounted for about 75 per cent of the cases in the State.
“Compared to other vector-borne diseases, Malaria is not a problem. There is no parasitic incidence among infants, which merely means there has been no case of positive malaria case among children below one year. This indicates that there is no acute, continuous transmission of malaria,” Dr. Elango explains.
Intensive surveillance of malarial cases has been one way of tackling the menace, explains a senior public health official at the Directorate of Public Health. “We even test cases of fever on suspicion. The percentage that tests positive is quite low, and dropping, but we do not want to take the risk of spreading infection,” he says. The number of blood smears tested for malaria continues to be high in the State (over 70 lakh in 2012, for instance).
The official further goes on to add that source reduction of larvae and mosquitoes are a serious business. Larvicide spraying and fogging are carried out regularly, to prevent breeding of the disease causing Anopheles mosquito.
The mosquito breeds in clear water, as in wells, uncovered over head tanks, or seepage collected at dam sites, he explains. In Chennai, the ‘Dry Day’ concept, where residents are requested to clean out their overhead tanks and keep them dry for a whole day, made a big difference in keeping down the number of malarial infections, Dr. Elango says.
“Unless the local government authorities and members of the public co-operate, no successes are possible in vector control,” according to the public health official. Government and private hospitals are aware enough to treat the fever cases, and if the patient tests positive, treat for malaria.
Malaria, however, is far from ceasing to be an issue in Tamil Nadu. While the numbers have come down, there is no room for complacency. “Unless the mosquito control measures are kept up, along with surveillance and testing, the State is sure to slip up. In addition, there is now the emerging issues of resistance: the vector’s resistance to insecticides, and patients’ resistance to one of the primary drugs, Choloroquine,” Dr. Elango says.