Résumé
Background: Dengue is one of the most rapidly spreading mosquito-borne viral diseases in the world. Aedes aegypti mosquito is the main vector of dengue and Chikungunya. Entomological surveillance on Aedes mosquito has been standardized on different indices like House index, Container index, Breteau index. Larval indices are important predictors of outbreaks and are valuable in taking preventive measures. The objectives of the present study was to study the trend of larval indices over four months in selected wards of Kaiparambu Panchayat, Thrissur, Kerala, India and to identify the major breeding sources.Methods: A series of surveys were conducted from May to August of 2017 in Kaiparambu Panchayat under the field practice area of Amala Institute of Medical Sciences Thrissur. Houses were selected serially from 4, 5 and 6 wards with roughly 120 houses being covered each month.Results: A total of 489 houses were surveyed over 4 months. Overall, positive containers (with larvae) were present in 375 of 4055 potential containers showing a calculated House index (HI) is 44.4%, Container index (CI) is 11.5% and the Breteau Index is 76.7%. All three indices increased from May to June, peaked in July and dropped by August. Plastic containers were the most common source of breeding.Conclusions: The indices indicate risk even in the pre-monsoon season and there is a marked rise during monsoon. Hence, control measures need to be adopted during the pre-monsoon season so as to reduce the impact of the impending outbreak.
Résumé
Background: Mosquito borne diseases are a major public health problem in Kerala. Mosquito density assessed by larval surveys is easier and quicker to perform. The larval indices are an important practical predictor of outbreaks of mosquito borne disease and are valuable in taking preventive measures. This study is done to calculate standardized larval indices namely house index, container index and Breteau index and to identify the major breeding sources of mosquitoes in the residential environment in a rural of Thrissur, Kerala.Methods: A cross-sectional study selecting 80 houses from 1 wards of Konnikara village under Thrikkur Panchayath under the field practice area of rural training centre, Amala Institute of Medical Sciences Thrissur. Every water holding container indoors and outdoors was counted and searched for larval presence and noted on a pretested format.Results: In this study, 80 houses were surveyed in 2 days initially in June and in September. All the entomological indices were found to be above the critical level in the initial survey in June. House index=36% container index=44%; Breteau index=143% showing high chances for outbreaks of mosquito borne diseases. In September though the indices were very low house index 1.25% container index 2.77% and Breteau index.Conclusions: The area is prone for mosquito borne disease outbreaks like dengue fever and after interventions the vector indices and potential risks came down
Résumé
A c1inico-epidemiological study of fever cases was carried out in three villages of Ambajogai Mandal, Beed, Maharashtra. Out of 123 fever cases studied, most common affected age group was 21-45 years with more number of females i.e.55.28%. The patients mainly presented with fever and joint pain with no any evidence of haemorrhagic manifestation. Of the 36 blood samples tested 03 samples were found positive for IgM antibodies to dengue virus. Larval survey showed highest breeding preference in domestic water container like earthen pots. Entomological indices were found out to be higher as house index 19.76%; container index 19.02%; Breteau index 22.31%. Clinico-epidemiological, laboratory and entomological investigations indicate present episode of fever outbreak was due to dengue fever. It demands for strengthening the surveillance activity and alert reporting of peripheral health staff along with IEC activities for community participation and involvement of other departments.