Micro filarial rate touched 0.07% this year
Lymphatic filariasis, or Elephantiasis, is well on its way towards being eliminated in Tamil Nadu.
“With the micro filarial rate dropping every year, it has reached a new low - 0.07 per cent - in 2011. The MF rate is the number of cases that test positive among all those screened in the community,” explains G.K.Durairaj, additional director (Malaria and Filaria), Directorate of Public Health.
Filariasis is mostly manifest as elephantiasis, a thickening of the skin and tissues of the legs, or lower body, though different worms can affect different parts of the body. The disease-causing ‘filariea' are spread by culex mosquitoes that breed in dirty and stagnant water.
In Tamil Nadu, 13 districts are said to be endemic to filariasis, and this is where prevention activity has been centered. These districts are Chennai, Kancheepuram, Tiruvallur, Vellore, Tiruvannamalai, Tiruchy, Villuppurm, Cuddalore, Nagapattinam, Tiruvarur, Thanjavur, Pudukkottai and Kanyakumari. Among these, the Tirupattur area in Vellore district and Thiruvannamalai were felt to be crucial segments.
The reason for the drop is a combination of public health efforts, Dr. Durairaj said. While fogging, anti larval and anti adult mosquito biocides spraying, and encouraging the use of mosquito nets is on regularly, what has turned the tide is probably the Mass Drug Administration (MDA) programme held periodically.
Under this programme, DEC (Diethyl Carbamazine) and Albendazole tablets are given to people in the age group 2 to 60 years in the endemic areas. “Every year one dose of both these drugs is given to patients as per WHO recommendation. This will kill any microfilaria presence effectively, and thereby, reduce the filariasis load in the community,” R.T.Porkaipandian, Director of Public Health, explained.
MDA was started first in Cuddalore district in 1998, in an effort to stem the tide of rising lymphatic filariasis cases. “Generally, MDAs are not conducted if the prevalence is less than one per cent. However, the State continues to do so though we reached an MF rate of 0.38 per cent in 2005 itself. This was just to ensure that the disease is eliminated,” he said.
Given the performance over the last few years, and the dropping rates, it is likely that there may be just one more MDA, to be held in Tamil Nadu, Dr. Porkaipandian added. “It may be safe to stop with just this one round, since we are at 0.07 per cent. Of course, a formal decision is yet to be taken in this regard.”
In contrast, the incidence of malaria, continues to remain a concern, especially in Chennai city and Rameswaram (in Ramanathapuram). About 14,000 cases are reported every year in the State. Additional manpower and strengthening of supervision is planned to reduce the burden, with the assistance of National Rural Health Mission, in Rameswaram, Dr. Durairaj said.