09 September 2010 - On 12 January 2010, the Haitian earthquake shook Port-au-Prince, Haiti's capital, causing widespread devastation. This natural disaster was shortly followed by a similar one in South America: on 27 February 2010, the Chilean earthquake occurred off the coast of the Maule Region of Chile, bringing with it chaos, disorder and economic disruption.
But natural disasters are not limited to earthquakes; there are also tsunamis, landslides, volcanic eruptions, hurricanes, tornadoes and floods. The most recent disaster situation took place in Pakistan, where heavy monsoon rains resulted in flooding that affected over 20 million people. This article addresses epidemics and disease flare-ups after disaster situations.
Natural disasters can threaten human lives directly and from disease impacts that follow a disaster. According to the US Centers for Disease Control and Prevention the risks for communicable disease transmission among people after natural disaster events are associated primarily with the size and characteristics of the population displaced, the proximity of safe water and functioning latrines, the number of animal and human fatalities, the nutritional status of displaced populations, the level of immunity to vaccine-preventable diseases, and the access to healthcare services.
Peoples' lives are also impacted as their livelihoods suffer. People have a right to food and a right to a standard of living. Where natural disasters impact these, there is a need for both immediate emergency relief and broader recovery actions.
Human diseases associated with natural disasters are often linked to lack of access to safe water and sanitation, to situations of crowding and close human contact with animals, to insect-transmitted diseases that are influenced by rainfall and humidity, and the presence of mosquitoes. Undoubtedly, the presence of large numbers of dead bodies and animal carcasses in disaster-affected areas heightens concerns of numerous disease outbreaks.
After an emergency situation, often a large number of dead animals require timely disposal either through burial or burning. In the case of floods, suitable disposal areas, dry firewood or other material to burn the carcasses may not be readily available. The smell and sight of decomposing bodies can cause distress and also pollute water supplies.
Outbreaks of anthrax, brucellosis, leptospirosis, rabies, salmonellosis and tularaemia generally have an animal origin. For example, after the displacement of people, there may be an increase in the number of stray dogs and marauding dogs forming groups can be observed. With this there is an increased risk of dog bites, some of which could create the risk of the transmission of rabies.
The safety of food, especially of animal origin, is one of the major concerns following emergency situations. The lack of adequate refrigeration facilities and the absence of inspection services can lead to unsafe products being marketed and consumed. The consumption of animals that have died during the event should be strongly discouraged.
Animals are also made more vulnerable to diseases through displacement and over-crowding, where they may experience diseases for which they have little or no immunity. Livelihoods are placed at risk as people's assets are exposed to disease and malnutrition, and markets for animals and animal products may be inaccessible.
A systematic and comprehensive evaluation should identify: (1) endemic and epidemic diseases in humans and animals that are common in the affected area as well as areas that may supply animals to the affected area in the recovery phase; (2) living conditions of the affected populations, including number, size, location, and density of settlements; (3) numbers of dead animals and humans; (4) availability of safe water and adequate sanitation facilities; (5) underlying nutritional status and immunization coverage among animal and human populations; and (6) degree of access to available healthcare facilities as well as functioning of veterinary services and the presence of effective crisis management and response units.
The UN Food and Agriculture Organization (FAO) works diligently to address emergency responses and recovery. Where transmissible and non-transmissible animal and zoonotic diseases occur after disastrous situations, FAO applies its knowledge of veterinary public health, epidemiology and crisis management in its effort to reduce disease risks, mitigate the impacts, and encourage public health communications.