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What is A malarial survey is conducted in 50 villages having a population of one lakh. Out of 20000 slides examined, 500 turned out to be malaria positive. The annual parasite incidence is - and explain in detail?
<> -Annual parasite incidence. = confirmed cases during one year *1000 ---------------------------------------------------------- Population under surveillance (0.5%) -It is based on intensive active and passive surveillance and cases are confirmed by blood examination. Reference : Park's textbook of preventive and social medicine, 23rd edition, pg no:261 <\>