Climate variability and infectious disease burden in Coastal Sindh, Pakistan: A trend analysis (2019-2022)

This study examines the spatio-temporal trends of climate-sensitive infectious diseases and their associations with climate variables in coastal districts of Sindh, Pakistan from 2019 to 2022.

An ecological time-series design was used to analyzed facility-level surveillance data from 166 primary health centers alongside meteorological data on temperature, humidity, and precipitation from ground-based monitors. Incidence rates for suspected malaria, diarrhea, dysentery, and typhoid were calculated. Temporal trends were assessed using the Mann-Kendall test, and Pearson correlations were used to examine associations with climate variables.

A total of 982,538 cases were recorded over the four-year period, with under-five diarrhea and suspected malaria being the most prevalent. Thatta district alone reported nearly 30,000 malaria cases in September 2022 following severe monsoon flooding. Malaria peaked 4-6 weeks after monsoon rainfall, while diarrhea showed dual peaks in March and during monsoon months. Significant positive correlations were found between disease incidence and temperature, humidity, and precipitation, particularly for malaria and diarrhea.

The study provides compelling evidence of the impact of climate variability on infectious disease patterns in coastal Sindh highlighting the need for climate-resilient health systems, enhanced disease surveillance, and integration of meteorological data into early-warning mechanisms.