Effects of Climatic Factors on Diarrheal Diseases Among Children in Nepal

Introduction

  • The incidence of diarrhea is a significant cause of morbidity and mortality in low-income countries like Nepal.
  • Diarrheal diseases are temperature-sensitive and are likely linked to climate change.
  • Climate change is associated with increased mean and variability of temperature and precipitation, leading to higher occurrences of water and food-borne diseases.
  • This ecological study aims to provide evidence connecting weather and climate with diarrhea incidence in Nepal.

Study Design and Methodology

  • Data Sources:
    • Monthly diarrheal disease data and meteorological data across all Nepalese districts from 2002 to 2014.
    • Diarrheal cases were obtained from the Health Management Information System (HMIS).
    • Meteorological data were acquired from the Nepal Department of Hydrology and Meteorology.
  • Data Analysis:
    • Log-linear regression models were used to assess relationships between temperature variables, rainfall, relative humidity, and diarrhea incidence.
    • Only predictors with p-values < 0.25 were included in the models.

Key Findings

Effects of Temperature
  • Mean Temperature:
    • A 1 °C increase in mean temperature is associated with a 4.4% increase in diarrhea incidence (95% CI: 3.95, 4.85).
    • Regional variations in susceptibility to increased diarrhea incidence exist (0.85% in Central Terai to 5.05% in Western Mountain).
  • Maximum Temperature:
    • A 1 °C increase corresponds to a 3.87% rise in diarrhea incidence, with regional variations between 0.74% to 5.22%.
  • Minimum Temperature:
    • A 1 °C increase in minimum temperature led to a 3.79% increase in diarrhea incidence.
Effects of Rainfall
  • Rainfall Impact:
    • A 1 cm increase in rainfall results in a 0.28% increase in diarrhea incidence (95% CI: 0.15, 0.41).
    • Regional increases vary, ranging from 0.37% in Eastern Hill to 0.80% in Mid-Western Hill.
Seasonal Variations
  • The highest incidence of diarrhea occurs in summer (11.63% increase, compared to winter), driven by monsoonal rains and warmer conditions.
  • Spring results in a significant decrease (-14.5%) in diarrhea cases, highlighting seasonal variability in disease incidence.

Discussion

  • The findings establish a robust link between climatic variables and diarrhea incidence.
  • Mountain regions display heightened sensitivity to climate variability, increasing the burden of diarrheal diseases.
  • Understanding these relationships enables improved resource allocation and the development of predictive models for diarrhea outbreak management.

Conclusions

  • Rising temperatures and changing precipitation patterns are likely to exacerbate the incidence of diarrheal diseases among children under five in Nepal.
  • These climatic influences necessitate enhanced surveillance, better health infrastructure, and pro-active public health policies to mitigate future risks associated with climate change.