Global Journal of Medical Research, F: Diseases, Volume 22 Issue 4

26 Year 2022 Global Journal of Medical Research Volume XXII Issue IV Version I ( DD ) F © 2022 Global Journals A Brief Study on the Prevalence of Malaria in Kolkata, West Bengal, India on malaria, limited data have been available specifically for age, gender, and seasonal variance [4]. The current study therefore focuses on some of these aspects. a) Background of the study After India attained independence in 1947, 75 million malaria cases had been estimated in a population of 330 million. During the eradication era in the late 1950s and early 1960s, remarkable malaria eradication had been achievement, with malaria cases significantly declining to just 100,000 cases in 1964. Unfortunately, the number of cases gradually increased thereafter, reaching 6.4 million by 1976 [5]. Nonetheless, despite having the highest burden of malaria within the Southeast Asian region, India has shown a declining trend in malaria incidence in recent years [2]. Malaria is essentially a protozoan infectious disease caused by four main Plasmodium species in humans, namely Plasmodium falciparum , Plasmodium vivax , Plasmodium ovale , and Plasmodium malariae . Among the aforementioned protozoans, P. vivax has caused majority of the deaths worldwide. Only female anopheles mosquitoes can be the vector for malaria. In terms of malaria transmission, approximately 30 out of over 400 different species can transmit malaria. Such mosquitoes mostly bite at night, with some resting outdoors and others indoors. A person bitten by a mosquito carrying the malaria parasite may become infected with malaria. Similarly, a mosquito without the malaria parasite who bites a person already infected with malaria may acquire the malaria parasite and subsequently infect another person [6]. The epidemiology of malaria in India is complex given the geo-ecological diversity, multiethnicity, and wide distribution of nine anopheline vectors transmitting three main Plasmodium species: P. falciparum , P. vivax , and P. malariae . The number of cases within the country still account for 6% of global malaria cases and approximately half of the total Plasmodium vivax cases worldwide [7]. Kolkata (formerly Calcutta), the capital of state West Bengal, India with an area of 205 km 2 , is under the jurisdiction of the Kolkata Municipal Corporation (KMC). According to 2011 census, Kolkata has a population of 45 lakhs. Kolkata has still been considered the most malaria-prone district of West Bengal, India given the conducive climatic condition and urban lifestyle maintained within the city. Over a century ago, the city provided Sir Ronald Ross an opportunity to eradicate the transmission cycle of the disease. Unfortunately, the transmission cycle of malaria has still yet to be interrupted permanently [8]. Nonetheless, the status of malaria within Kolkata has improved considerably over last decade under the keen supervision of the officials of the KMC [9]. b) Objective The current study aimed to investigate the present status and trends of malaria in a designated ward under the jurisdiction of the KMC to determine timing, location, and distribution of malaria cases, as well as identify risk factors to mitigate future outbreaks. II. M aterials and M ethods A cross-sectional study was designed based on data collected from the KMC documents and a pretested questionnaire administered to Taltala area residents during the winter. For ethical consideration, verbal or written approval was taken from the residents. Variables taken into account included age, sex, malaria category, medicine intake history, and others. Most of the wards were also found to be at high risk for malaria peaking during the postmonsoon season. Appropriate statistics had been utilized for the present study. The study included a total of 120 participants who were interviewed using pretested questionnaires on socio– demographic parameters, education, occupation, household information, and malaria-related behavior upon recruitment. A medical history was taken, after which a clinical examination was performed in all patients using standard protocol. Weight and height were measured following the standard anthropometric protocol. Body mass index was calculated as kg/m 2 . Fever was defined as an axillary temperature ≥37.5 °C. Venous blood was collected in ethylenediaminete- traacetic acid vials. Malaria parasites were counted per 200 white blood cells on Giemsa-stained thick blood films, whereas parasite species were defined based on thin-film microscopy. III. R esults Table 1: Kolkata Municipal Corporation showing indicators of malaria intervention Borough ABER SPR API 6 9.61 15.6 15.53 ABER, annual blood examination rate; SPR, slide positivity rate; API, annual parasite incidence. Table 2: Distribution of malaria category Groups N = 120 Percentage (%) Plasmodium vivax (PV) 105 87.5 Plasmodium falciparum (PF) 15 12.5