Risk of malaria transmission in stone quarry sites of Villupuram district in Tamil Nadu, India

Abstract

Movement of labourers from malaria endemic areas into non-malarious places for employment in quarry industries poses threat on transmission of malaria. Such situation was prevailing in Villupuram District of Tamil Nadu, where there were earlier reports of occurrence of malaria. Therefore, the risk of malaria transmission was assessed in the area with quarry industries. Malaria parasite (Plasmodium species) infection in human was diagnosed. Sixteen mosquito species were recorded from the larval samples and 13 species were recorded in adult collection. PCR assay showed that, out of 50 mosquito pools, 3 pools of An. subpictus were found positive for P. vivax infection (MIR: 1.09). Three P. vivax positives (asymptomatic) were detected among migrant labourers and one positive among the villagers. Two asymptomatic P. falciparum infections were found among the school children. Thus, the area with both vulnerability and receptivity was under risk of establishmant of a focus for indigenous transmission of malaria, necessitating surveillance and containment measures.