Impact of disasters on public health – part 1

by Reynold Hewitt Tue, Jul 20, 2010

Disasters have claimed millions of lives throughout the world be it natural or man-made. Natural disasters include weather phenomena such as tropical storms, extreme heat or extreme cold, winds, floods, earthquakes, landslides and volcanic eruptions. Disasters caused by humans include transportation accidents, industrial accidents, release of hazardous materials and the collapse of buildings.{{more}}

Disasters are still widely thought of as sudden onsets of cataclysmic events. However, disasters such as famine and global climate change could be considered ‘slow-onset’ disasters. As odd as the idea sounds, disasters can even be ‘chronic’ – that is: continually occurring over a protracted period of time and may affect people all over the world every year, resulting in the generation of international refugees and internally displaced persons.

Man-made disasters include fires, chemical explosions, train accidents, hazardous materials etc. and the presence of refugees. These often occur as a result of lack of maintenance or carelessness, resulting in the loss of lives.

The Caribbean area is vulnerable to natural disasters, such as hurricanes, volcanic eruption, floods and earthquakes. There have been many significant Hurricanes in the Caribbean region such as hurricane Janet in 1955 and hurricane Allen in 1980. Earthquakes have also occurred in Trinidad and Tobago, Jamaica and Antigua.

On January 12, 2010 Haiti was impacted on by a 7.5 magnitude earthquake that devastated and damage Port-au-Prince and environs. Vital infrastructure necessary to respond to the disaster was severely damaged or destroyed. This included all hospitals in the capital; air, sea, and land transport facilities; and communication systems. This is a typical example of the harmful effects of a natural disaster on populations. The quake affected the three Médecins Sans Frontières (Doctors without Borders) medical facilities around Port-au-Prince, causing one to collapse completely. A hospital in Pétionville, a wealthy suburb of Port-au-Prince, also collapsed, as did the St. Michel District Hospital in the southern town of Jacmel, which was the largest referral hospital in south-east Haiti.

The earthquake in Haiti affected areas that were affected by poverty, absence of building codes and where there was no disaster preparedness plan.

The Haiti earthquake killed approximately 217,366 people. More than 500,000 people have left Port-au-Prince for outlying areas, including nearly 100,000 who have gone to Grand Anse and more than 160,000 to Artibonite. The Government estimates that 97,294 houses were destroyed and 188,383 were damaged. Disasters are considered to be devastating when there is a loss of human lives.

According to the International Federation of the Red Cross and Red Crescent Societies, in 2002, international disasters affected 608 million people and killed more than 24,000. Disasters are unusual public health events that overwhelm the coping capacity of the affected community.

Public Health events are triggered by natural, man-made and other disasters. Usually the risk of a communicable disease in a community affected by a disaster is proportionate to endemic levels. There is generally no risk of a given disease when the organism which causes it is not present beforehand. When disaster impacts on a population, there is usually population displacement, ecological changes, disruption of utilities and interruption of public health services.

Most disasters have sudden impact, though some, such as droughts and famines, are somewhat awkwardly called ‘slow onset’ disasters. In some cases, there may be warnings, such as weather predictions. Getting these warnings to those at risk is often difficult in developing countries. Despite the increase in technology and early warnings, there is little many people can do in the absence of disaster preparedness or adequate resources. This is evident by scale of loss from hurricane Katrina in 2005 in the United States, the earthquakes and wildfires in the western U.S., and the recurring tornados that blanket areas of the Midwestern and southern United States were devastating, despite warnings.

The most obvious impact on the health of a population affected by a disaster is illness, disability, injuries, and death; direct losses in infrastructure; and loss or disruption in health care delivery. The impact may be Physical (deaths, injuries, food scarcity, homelessness, disease outbreak, displacement of population), economic (destruction of crops, destruction of hospital property, disruption of production, setback to economic development programmes) and psychological (Loss of spirit and low morale of citizens, trauma of displacement, loss of productive faith in the future) creating a loss of income.

The immediate health burden depends on the nature of the hazard. In the aftermath of a major disaster, authorities must meet extraordinary demands with resources that cannot begin to meet even basic health needs and that often have been drained by the immediate emergency response. Disasters related to natural events may affect the transmission of preexisting infectious disease, but the imminent risk of large outbreaks in the aftermath of natural disasters is often overstated. In the short-term, an increased number of hospital visits due to diarrheal diseases, acute respiratory infections, dermatitis, and other causes should be expected following most disasters. In the medium term, heavy rainfalls may affect the transmission of vector-borne diseases, for example, from residual water that may contribute to an explosive rise in mosquitoes. There may be increases in leptospirosis cases, dengue fever and gastroenteritis.

The health burden of disasters includes damage to housing, schools, channels of communication, and industry. Damage to hospitals, health facilities, and water and sewage systems have the biggest impact on health. The long-term health burden includes loss of medical care, interruptions in the control of communicable disease and other public health programs, and loss of laboratory support and diagnostic capabilities of hospitals. A common misperception is that the damage to critical health facilities is promptly repaired, but experience shows that damaged health infrastructure recovers at a slower pace than other service sectors, such as trade, roads, bridges, telecommunications, and housing.

Different types of disasters result in different patterns of injury and these in turn produce variable levels of morbidity and mortality. Generally it is believed that earthquakes are capable of producing large numbers of deaths. Earthquakes and high wind events such as tornados are capable of producing large numbers of severe injuries requiring intensive care.

If earthquakes occur when people are either in or close to buildings, large numbers of injuries result. While most are not life-threatening, the injured do require immediate medical care from health facilities that are often unprepared, damaged, or totally destroyed. Authorities must provide services to a displaced population, rehabilitate health facilities, restore normal services, and strengthen communicable disease surveillance and control. They must also attend to the long-term consequences, such as permanent disabilities, mental health problems, and possibly increases in rates of heart disease and chronic disease. Therefore, if the Public Health System is damaged or destroyed it is often difficult to treat the injured, consequently resulting in loss of limbs, disability or death.

– To be continued