Background. Larval indices such as the house index (HI), container index (CI), and Breteau index (BI) are widely used as alarm signals to interpret vector-borne diseases in surveillance programs. Presently, larval indices such as house index > 10% or container index > 5% or Breteau index > 50% are used as alarm signals to detect outbreaks of mosquito-borne diseases. However, some areas remain missing for active surveillance due to guidance posed to health workers for active surveillance. The present study aims to investigate the new modified cut-off points for early intervention of Aedes aegypti for the district of Solapur southwestern region of Maharashtra state in India.

Methods. The present retrospective study of four-year record of dengue outbreaks was taken to test-validity of Aedes larval indices in the Solapur district. The data of HI, CI, and BI, during, and after the outbreak of respective areas were collected from 2019 to 2022. Receiver operating characteristic (ROC) curves were used to determine the thresholds to find modified cut-off points for early detection of mosquito-borne outbreaks.

Result. The HI_MAX (maximum block HI in a radius of 100m) had an area under the ROC curve of 64.5.%. At the cut-off of 8%  the predicted transmission is with 46.8% sensitivity and 81.1% specificity. The CI_MAX (maximum block CI in a radius of 100m) had an area under the ROC curve of 64.5%. At the cut-off of 4.13% the predicted transmission is with 39.2% sensitivity and 84.6% specificity. The BI_MAX (maximum block BI in a radius of 100m) at 2-month intervals had an area under the ROC curve of 67.6%. At the cut-off of 7.69%  the predicted transmission is with 50.6% sensitivity and 77.6% specificity.

Conclusion. In conclusion, the specified standard values may serve as reliable indicators for the timely identification of dengue outbreaks and as a guide for the implementation of targeted vector management strategies. The overarching goal is to effectively manage dengue epidemics by maximizing the prudent allocation of financial, technical, and human resources.

larval indices, house index (HI), container index (CI), Breteau index (BI), receiver operating characteristic (ROC) curve.

Received: October 29, 2023; Accepted: December 1, 2023; Published: December 6, 2023

How to cite this article: Sanjay Mulaje, Digambar Zombade and Ramesh Patil, On statistical detection of larval indices: an innovative strategy for control of mosquito-borne diseases in the district of the southwestern region of Maharashtra, Far East Journal of Theoretical Statistics 68(1) (2024), 81-92. http://dx.doi.org/10.17654/0972086324005

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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