Disaster and then Disease

By Elizabeth Batt

The International Federation of Red Cross and Red Crescent Societies, describes a natural disaster as a “sudden, calamitous event that seriously disrupts the functioning of a community or society and causes human, material, and economic or environmental losses that exceed the community’s or society’s ability to cope using its own resources.”

The earthquake in Haiti that occurred on January 12, 2010, caused death and destruction, the extent of which has yet to be realized. Sadly, Haiti’s problems might be only just beginning. Often following the initial aftermath of any natural disaster there follows a second wave of deaths, caused by disease.

Types of Disease Prevalent in the Aftermath of a Natural Disaster
When a natural disaster strikes to the extent that it did in Haiti, the infrastructure of a country is decimated. Fresh water supplies, sewage disposal and power is destroyed or severely interrupted. What remains is often contaminated, initiating a vicious cycle that cultivates communicable diseases. In a third world country like Haiti, where resources are already stretched thin and immunizations are not standard practice, the loss of life is certain to be much higher because they’re simply not equipped to deal with an incident of this magnitude.

The study, “Management of dead bodies in disaster situations.” PAHO; 2004, indicates that little threat for communicative disease outbreak is posed by actual human remains. The threat comes from the survivors themselves, the destruction of their surroundings and an inevitable crowding situation caused by displacement. Without a continuous fresh water supply, survivors are forced to drink polluted water just to stay alive. Aided by the lack of adequate sanitary conditions, these pollutants are ingested and then defecated back into the water source. It becomes a breeding ground for communicable diseases.

Water-related Diseases
Water-related diseases include infectious diarrhea or norovirus, salmonella and cholera. Noroviruses are transmitted through the fecal-oral route after the ingestion of contaminated food and water. Once infected, a person-to-person transmission can occur. Noroviruses cause diarrhea and vomiting that without adequate sanitization amenities, continue to perpetuate.

Salmonella is often referred to as food poisoning. It causes the same symptoms as norovirus and can be present in almost any type of food. Salmonella is transmitted through infected feces that come into contact with a food source. People can become carriers of salmonella, transmitting the disease for life.

Cholera, transmitted by the fecal-oral route has an extremely brief incubation period of just 2-5 days. It can cause acute diarrhea, dehydration and kidney failure. Of all water-related diseases, cholera is perhaps the most insidious and can kill an adult within hours.

Crowding-related Diseases
The three most common crowding-related diseases are meningitis, measles and acute respiratory failure (ARF). Meningitis causes an inflammation of the membranes surrounding the brain and spinal cord and can lead to permanent neurological damage. Measles is a highly contagious viral disease that can cause seizures and coma. The complications of measles can include blindness and brain inflammation. ARF has a high morbidity rate of 50-70% in both children and adults. Caused by inadequate gas exchange, oxygen levels drop and carbon dioxide levels rise. An effect of displacement, over-crowding issues and poor nutrition, ARF is a major cause of death.

Vectorborne Diseases
Vectorborne diseases are caused by “vectors” such as mosquitoes that carry malaria. Earthquakes and other natural disasters can change a habitat, as evidenced in Saenz R, Bissell RA, Paniagua F. "Post-disaster malaria in Costa Rica." Prehospital Disaster Med. 1995;10:154–60. This change in habitat can create conditions that are ripe for breeding, causing an upsurge in outbreaks of malaria. Children are particularly at risk of contracting malaria, a virus that in its most dangerous form, can affect the brain and kidneys. Dengue, also carried by mosquitoes, can develop into dengue haemorrhagic fever. The spread of dengue can be directly related to inadequate solid waste disposal and water storage. Without treatment, fatality rates can exceed 20%.

Haiti's challenges are far from over and despite aid being sent to this ravaged country, the death toll as it stands now, is certain to rise.