Epidemiological analysis of respiratory and intestinal infectious diseases in three counties of Sichuan: the baseline survey of Disaster Mitigation Demonstration Area in western China

Hysteresis effects of different levels of storm flooding on susceptible enteric infectious diseases in a central city of China

BACKGROUND

Recently, attention has focused on the impact of global climate change on infectious diseases. Storm flooding is an extreme weather phenomenon that not only impacts the health of the environment but also worsens the spread of pathogens. This poses a significant challenge to public health security. However, there is still a lack of research on how different levels of storm flooding affect susceptible enteric infectious diseases over time.

METHODS

Data on enteric infectious diseases, storm flooding events, and meteorology were collected for Changsha, Hunan Province, between 2016 and 2020. The Wilcoxon Rank Sum Test was used to identify the enteric infectious diseases that are susceptible to storm flooding. Then, the lagged effects of different levels of storm flooding on susceptible enteric infectious diseases were analyzed using a distributed lag nonlinear model.

RESULTS

There were eleven storm flooding events in Changsha from 2016 to 2020, concentrated in June and July. 37,882 cases of enteric infectious diseases were reported. During non-flooding days, the daily incidence rates of typhoid/paratyphoid and bacillary dysentery were 0.3/100,000 and 0.1/100,000, respectively. During flooding days, the corresponding rates increased to 2.0/100,000 and 0.8/100,000, respectively. The incidence rates of both diseases showed statistically significant differences between non-flooding and flooding days. Correlation analysis shows that the best lags for typhoid/paratyphoid and bacillary dysentery relative to storm flooding events may be 1 and 3 days. The results of the distributed lag nonlinear model showed that typhoid/paratyphoid had the highest cumulative RR values of 2.86 (95% CI: 1.71-4.76) and 8.16 (95% CI: 2.93-22.67) after 4 days of general flooding and heavy flooding, respectively; and bacillary dysentery had the highest cumulative RR values of 1.82 (95% CI: 1.40-2.35) and 3.31 (95% CI: 1.97-5.55) after 5 days of general flooding and heavy flooding, respectively.

CONCLUSIONS

Typhoid/paratyphoid and bacillary dysentery are sensitive enteric infectious diseases related to storm flooding in Changsha. There is a lagging effect of storm flooding on the onset of typhoid/paratyphoid and bacillary dysentery, with the best lagging periods being days 1 and 3, respectively. The cumulative risk of typhoid/paratyphoid and bacillary dysentery was highest at 4/5 days lag, respectively. The higher of storm flooding, the higher the risk of disease, which suggests that the authorities should take appropriate preventive and control measures before and after storm flooding.

Related Factors Associated With Earthquake Inpatient Mortality

OBJECTIVES

To date, we have only limited evidence of the determinants of earthquake inpatient mortality-related factors. This study is among the first to explore related factors of inpatient deaths using data from multiple hospitals and multiple earthquakes.

METHODS

We included and retrospectively analyzed data on 32,976 earthquake inpatients in the West China Earthquake Patients Database. Of these, we analyzed the records of 284 patients who died during hospitalization. We collected 12 dichotomous variables with reference to previous reports: patients' age (both ≤ 15 years and ≥ 65 years), gender, prehospital treatment, intensive care unit (ICU) admission, the presence of severe traumatic brain injury (TBI), trunk injury, severe poly-trauma, crush syndrome, multiple-system organ failure (MSOF), infection, and cardiac/respiratory disease. We performed multivariate logistic regression analysis to explore independent related factors of mortality.

RESULTS

Ultimately, we identified severe TBI, MSOF, old age (≥ 65 years), ICU admission, crush syndrome, and cardiac/respiratory disease as independent mortality-related factors. Severe TBI was the greatest risk factor of inpatient death (ods ratio [OR], 31.913, 95% confidence interval [CI], 20.484-49.720), followed by MSOF (OR 30.905, 95% CI, 21.733-43.947).

CONCLUSION

To reduce earthquake inpatient mortalities, the related factors analyzed in this study should be prioritized in future inpatient earthquake response strategies.