Effects of hydro-meteorological and geological disasters on vaccine-preventable disease outbreaks and routine immunisation amongst children: A scoping review.

Hydro-meteorological and geological disasters can pose serious harm to community health, such as an increased risk of infectious diseases and related mortality. We conducted a scoping review to compile the available literature on the effects of hydro-meteorological and geological disasters on routine immunisation and vaccine-preventable disease (VPD) outbreaks among children and adolescents under 18 years. We searched Medline, Embase, Global Health, Scopus, and Web of Science for original studies and systematic reviews on the topic published by the 21st of October 2024. We included studies that quantitatively analysed the effect of any of the thirty Emergency Events Database (EM-DAT) recognised hydro-meteorological and geological disasters (or those fitting EM-DAT criteria) on a comprehensive list of World Health Organization (WHO)-recommended vaccines and the 23 diseases against which they prevent. We included 26 studies, of which 19 concerned with vaccine-preventable disease outbreaks and seven focused on routine immunisation disruption.. Our review indicates that floods, cyclones, droughts, extreme temperatures, tsunamis, and earthquakes may result in vaccine-preventable disease outbreaks and routine immunisation disruption, and identified young children and refugees as at-risk populations. Flooding was reported to be associated with water-borne and vector-borne vaccine-preventable disease outbreaks such as malaria. Poor water, sanitation and hygiene (WASH) were further recognised as facilitating conditions for vaccine-preventable disease outbreaks after disasters. The vaccination studies reported reduction in routine immunisation rates in the months following a disaster, considering infrastructural damage to health facilities and vaccine storage issues as common causes. Finally, there was significant knowledge gap on the effects of specific disasters (e.g., wildfires and volcanic eruptions) and diseases (e.g., influenza, yellow fever, malaria, and dengue).In conclusion, our review reinforce the need for better policies to ensure vaccine equity, resilient health system and safe WASH to prevent vaccine-preventable disease (VPD) outbreaks following hydro-meteorological and geological disasters.