Risk factors for communicable diseases in humanitarian emergencies and disasters: Results from a three-stage expert elicitation

Abstract

Background: Humanitarian emergencies including disasters associated with natural hazards, conflict, complex emergencies and famines can pose significant risks to public health, especially when they lead to population displacement into inadequate conditions. To reduce the risk of communicable disease outbreaks in such situations it is necessary to know the key risk factors, their thresholds (quantitative risk factors only) and their relative importance in different types of emergencies. Methods: We conducted a three-stage structured expert elicitation. Experts from the fields of health protection and humanitarian assistance were invited to complete three successive online questionnaires. Experts were asked to choose the 20 most critical risk factors and in subsequent rounds to determine thresholds for urgent (yellow threshold level) and critical action (red threshold level). Additionally, experts were asked to assign weights for the risk factors in different emergency types. Results: We identified 20 key risk factors, which include factors related to water, sanitation and hygiene, access to health care, vaccination, nutrition, political will and others. Nine out of the 20 risk factors were quantifiable, for those risk factors yellow and red thresholds are given. 11 risk factors were qualitative. All risk factors scored highly when weighted in different emergency types and differences between risk factor weights in different types of emergencies were limited. Conclusion: Communicable disease risks in humanitarian emergencies are a nexus of complex and often interrelated individual issues. Knowing key risk factors and their thresholds and weight in different types of emergencies can help guide emergency response and risk reduction efforts.