Integrating wastewater surveillance and meteorological data to monitor seasonal variability of enteric and respiratory pathogens for infectious disease control in Dhaka city.

Background: Seasonal meteorological variations influence the spread of infectious diseases. Wastewater surveillance helps understanding pathogen transmission dynamics, particularly in urban areas of climate-vulnerable countries like Bangladesh.

Methods: We analysed 54 weeks of wastewater surveillance, clinical surveillance, and meteorological data from Dhaka, Bangladesh. Samples from 11 sites were tested for Vibrio cholerae (V. cholerae), SARS-CoV-2, Salmonella enterica subspecies enterica serovar Typhi (S. Typhi), and Group A rotavirus. Diarrhoeal Disease Surveillance data were sourced from icddr,b, and meteorological data from the Bangladesh Meteorological Department. Regression models adjusted for site and time variations were used for statistical analysis.

Results: Proportion of confirmed cholera cases among the diarrhoeal disease surveillance recruits were highest during post-monsoon (coef: 2.53; 95 % CI: 0.41 to 4.67; p = 0.029). V. cholerae log10 concentrations in wastewater were positively associated with pre-monsoon (coef: 0.93; 95 % CI: 0.26 to 1.58; p = 0.010), while SARS-CoV-2 peaked during monsoon (coef: 1.85; 95 % CI: 0.96 to 2.73; p < 0.001). S. Typhi and rotavirus log10 concentrations showed negative associations with pre-monsoon (coef: -0.96; 95 % CI: -1.68 to -0.27; p = 0.011, and -0.84; 95 % CI: -1.17 to -0.50; p < 0.001, respectively). Temperature positively influenced log10 concentrations of V. cholerae (adj. coef: 0.09; 95 % CI: 0.02 to 0.15; p = 0.014) and SARS-CoV-2 (adj. coef: 0.19; 95 % CI: 0.10 to 0.27; p < 0.001), but negatively associated with rotavirus (adj. coef: -0.06; 95 % CI: -0.10 to -0.03; p < 0.001). Similar associations were found between pathogen-positive samples and temperature.

Conclusion: Our study shows that seasonal, and meteorological factors (particularly temperature) influence the patterns and abundance of pathogens in wastewater and help in understanding disease transmission across different weather patterns.