Ecological Dynamics of Culex quinquefasciatus Larval Habitats in Purulia, India.

Mosquito-borne diseases remain a major global public health concern, with Culex quinquefasciatus acting as an important vector of lymphatic filariasis. This study investigated ecological and physico-chemical characteristics of larval breeding habitats across 14 villages in the Ajodhya Hill Forest, Purulia, India, between November 2023 and September 2024. Per-dip larval density (PDLD) was highest in polluted drains near human habitations (38.4 ± 1.5 larvae/dip), compared to ponds (25.53 ± 0.70) and roadside ditches (10.46 ± 0.35). Aerobic heterotrophic bacterial counts ranged from 4.13 × 105 to 21.56 × 105 cfu, with significantly greater microbial loads in organically polluted habitats. Correlation analysis revealed strong positive associations of PDLD with turbidity (r = 0.943), total dissolved solids (r = 0.919-0.963 depending on bacterial indicators), and bacterial abundance, whereas dissolved oxygen showed a negative correlation (r = - 0.890). Principal component analysis indicated that the first axis explained 53.1% of total variance. Artificial neural network modeling further identified turbidity and total dissolved solids as the most influential predictors of larval density, achieving low prediction error (training SSE = 0.056). These findings demonstrate that organically enriched, microbially active habitats strongly promote Cx. quinquefasciatus proliferation and highlight the potential of ecological and microbial indicators for targeted vector management.