What is the annual blood examination rate in West Bengal?
The annual blood examination rate (ABER) is a measure of the level of diagnostic monitoring activity. Data from 2007 suggested the ABER in West Bengal was around 5%, which is well below the level of 10% which is recommended for active surveillance and is the target of the National Vector Borne Disease Control Programme.
However, within West Bengal there is variation in the ABER both geographically and temporally. One study showed that in Naxalbari block in Darjeeling district, ABER in 2003 and 2004 was as low as 3.5%. The region experienced a malaria outbreak in late 2005, and the average ABER for this year soared as high as 16%; however, from January to May of 2005, before the transmission season and the outbreak, the ABER was only 0.5%! This means that monitoring efforts at the start of the outbreak were probably insufficient to detect the emergence of the outbreak and therefore delayed the process of responding to the emerging disease threat. Maintaining sufficient levels of malaria surveillance monitoring is particularly important in West Bengal, since this state is one of the major endemic centres for malaria in India, contribution about 11% of all malaria cases and about 6% of all cases of Plasmodium falciparum.