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Complex emergency/population movement

Complex emergency/population movement

Last update: 2022-03-22

Key facts

  • Population movement often results from a combination of hazards, either manmade and/or natural.  
  • Complex emergencies can lead to significant population movement and epidemics. These also often result in the collapse of the health system. 
  • Increase of population movement is exacerbated by climate change. 
  • The population is often affected by malnutrition, epidemics and poor health overall. Specific health needs and vulnerabilities exist before, during and after population movements. 

Main health impacts

Health concern Risk factors
Malnutrition/micronutrient deficiency

Insufficient nutrient intake leading to increased vulnerability to infection, morbidity and mortality.  

Vulnerable groups including children under five years of age, pregnant and lactating women, and people with chronic illness such as HIV and TB are especially at risk. 

Diarrhoeal diseases Limited access to water supplies and sanitation services lead to diarrhoeal diseases. During population movements, increased vulnerability can lead to large scale outbreaks of cholera and other infectious diseases. Lack of and/or delay in treatment and illness itself contributes to deteriorating nutritional status and makes malnourished people more vulnerable.
Vector-borne diseases  Lack of suitable shelter and lack of access to bed nets or other preventive measures increase exposure to and risk of vector-borne diseases 
Respiratory illnesses, skin infections and vaccine-preventable diseases  Significant population displacement and overcrowded, communal emergency shelters coupled with poor hygiene, can lead to respiratory illnesses or skin diseases. High insecurity in complex emergencies can lead to the disruption of routine health services such as vaccination programmes, therefore increasing the risk of transmission of vaccine-preventable diseases, namely measles.
Overall adverse health outcomes Conflict and violence can lead to damage to health facilities and disruption to provision of health care services. During population movements some groups may be unable to access existing services due to a range of obstacles (e.g. inability to use services in other countries, high costs), therefore limiting access not only to primary health care such as maternal and child health services, but also to essential care for chronic noncommunicable diseases (NCD).