Abstract:
Climate change has led to an increasing frequency and intensity of extreme climate events such as heat and drought extremes with considerable global public health burden. This systematic review collected 87 domestic and international studies from 2000 to 2023, considering the impacts of heat extremes, drought extremes, and compound hot-dry events on infectious diseases attributable to various transmission pathways such as waterborne, foodborne, insect-borne, airborne, and contact-transmitted diseases. Our results showed that high temperature was associated with increased transmission risks of waterborne and foodborne diseases including infectious diarrheal diseases (cholera, dysentery, typhoid, and paratyphoid) and infectious gastroenteritis; vector-borne diseases including dengue fever, Zika virus (ZIKV) disease, chikungunya fever, malaria, West Nile fever, and Rift Valley fever; airborne diseases including influenza-like diseases, influenza A, measles, and mumps; and contact-transmitted diseases including HIV/AIDS, schistosomiasis, and leptospirosis. Additionally, drought conditions also amplified the transmission risks of waterborne and foodborne diseases including cholera,
Escherichia coli infection, rotavirus infection, and hepatitis E; vector-borne diseases such as scrub typhus, schistosomiasis, hemorrhagic fever with renal syndrome, and West Nile fever; airborne diseases including meningococcal meningitis, pertussis, measles, and upper respiratory infections; and contact-transmitted diseases such as HIV/AIDS. Along with global warming, the frequency of compound high temperature and drought events shows a considerably increasing trend, causing more adverse health effects than heat or drought alone. However, there is limited research quantifying their effects on infectious diseases. These associations may be mediated through temperature and precipitation on infectious disease pathogens, transmission vectors, population susceptibility, public health services, and behaviors. In the context of climate change, the increasing occurrence of compound events of high temperatures and droughts raises health concerns, and further studies are needed to enhance our understanding of the impacts of climate change on infectious diseases and improve human adaption to climate change.