Key facts

The impact depends on the intensity, duration, day and time of day the earthquake hits. It also depends on the quality of buildings and infrastructure (such as roadways and bridges). There is a larger impact in areas of high population and building density.

Earthquakes generally occur without warning. Aftershocks can remain a significant hazard, causing further damage and increasing the psychological stress of both affected communities and humanitarian workers.

In the immediate aftermath, earthquakes can result in other health hazards including fires, landslides, avalanches, tsunamis and soil liquefaction (ground instability).

Earthquakes can damage health facilities and interrupt services, impacting access to essential care. They can be followed by a large influx of search and rescue and medical teams.

Main health impacts

Health concern	Risk factors
Mental health consequences	Mental health impacts including (but not limited to) severe anxiety, post-traumatic stress disorder (PTSD), and depression may occur as a result of experiencing the trauma of an earthquake (for example, homelessness; losing loved ones; loss of livelihood; etc.) Experiencing multiple traumatic events can lead to compound or complex trauma
Trauma or injury	Building collapse causes the majority of trauma, but other injuries can occur from landslides, fires or tsunamis triggered by the earthquake. Mortality and the injury peak are usually within the first 72 hours.
Diarrhoeal diseases	Contamination of water supply can occur when sanitation facilities are damaged or destroyed. Displacement or destroyed homes can lead to difficulty maintaining proper sanitation and hygiene practices which can lead to problems such as diarrhoeal diseases.
Respiratory illnesses, skin disease and vaccine- preventable diseases	Earthquakes may lead to population displacement. Overcrowded, communal emergency shelters, coupled with difficulty maintaining proper sanitation and hygiene practices can lead to problems such as respiratory illnesses, skin diseases and some vaccine-preventable diseases. A major earthquake can cause severe damage to health facilities and lead to the disruption of routine health services such as vaccination programmes, increasing the risk of transmission of vaccine-preventable diseases.
Vector-borne diseases	Flooding and break-down in waste management and sanitation services can lead to areas of stagnant water and an increase in certain vector (for example, mosquito) breeding sites. Interruption of solid waste management can result in certain vectors (for example, rats) coming into closer contact with humans (due to increased feeding sites and breeding grounds).
Overall adverse health outcomes	Damage to health facilities and means of communication, power and stock disruptions, and staff absenteeism limit access to all health care services from emergency care, maternal and child health services and essential care of noncommunicable diseases (NCDs).

Disease tools that may be relevant

Acute diarrhoea

Cholera

Hepatitis A

Hepatitis E

Typhoid fever

Acute respiratory infections preventable by vaccine - Diphtheria, chickenpox, mumps, rubella, whooping cough

Measles

Meningococcal meningitis

Poliomyelitis (polio)

Chikungunya

Dengue fever

Malaria

Zika virus infection

Acute respiratory infections (ARIs)