Post-earthquake Public Health in Haiti

Special Feature

By Stan Deresinski, MD, FACP, Clinical Professor of Medicine, Stanford, Associate Chief of Infectious Diseases, Santa Clara Valley Medical Center, is Editor for Infectious Disease Alert.

Synopsis: At a depth of 13 km, and just 25 km from Port-Au-Prince, Haiti, a fault system along the boundary separating the North American and Caribbean plates abruptly experienced a rapid acceleration of its usual super-slow motion lateral strike slip faulting. On January 12, 2009, at 16:53 local time, the result was the devastation of portions of the western third of the island of Hispaniola by an earthquake of magnitude 7.0 on the Richter scale. This was not the first earthquake to strike Haiti — Port-Au-Prince was largely destroyed by one in 1770 — but it appears to be the strongest recorded. It has been estimated that the number of deaths directly resulting from the event exceeds 50,000, perhaps by many tens of thousands. The injured must be dealt with and the population provided water and food. The conditions created by the devastation, particularly in a country that some considered a disaster before the earthquake, will produce a colossal public health challenge. WHO has posted a preliminary statement aimed at facilitating the response to the challenges presented by this calamity.

Source: Public health risk assessment and interventions. Earthquake: Haiti. January 2010 World Health Organization. Communicable Diseases Working Group on Emergencies, WHO headquarters Communicable Diseases Surveillance and Response, Pan American. Disclaimer: WHO reference number: WHO/HSE/GAR/DCE/2010.1 http://www.who.int/diseasecontrol_emergencies/publications/haiti_earthquake_20100118.pdf

Haiti, with a 2007 population of 9.7 million, is the poorest country in the Western Hemisphere, with 55% of households earning less than one U.S. dollar a day. Before the earthquake, 45% of the population lacked access to safe water and 83 lacked access to adequate sanitation. Most health care is provided by traditional healers. Malnutrition is commonplace, and multiple infectious diseases, including HIV and tuberculosis, are endemic. Vaccination rates are inadequate (see Table 1).

Table 1

Traumatic injuries, including crushes and burns, are common after earthquakes. These obviously necessitate the availability of surgical facilities and intensive care — which will require evacuation to medical facilities in other countries. These will also result in infections, including gangrenous ones. The limited vaccination coverage of the population makes tetanus an important risk, as was seen in Aceh after its tsunami. The injuries and infections, as well as the lack of drinking water in a hot tropical climate, will lead to many cases of acute renal failure, necessitating dialysis.

The lack of safe drinking water is not likely to be solved by rain since, during the winter dry season, there are only an average of three days with measurable rainfall, yielding a total of 32 mm in the month of January. Water that is available is often not safe, putting the population at risk of water-borne diseases, such as typhoid, hepatitis A, and hepatitis E. Leptospirosis is endemic in Haiti but, fortunately, cholera is not. Polio has been eliminated from Haiti.

Resettlement of displaced individuals to camps often results in crowding (although crowding in urban Haiti existed already), with resultant transmission of a number of respiratory infections, including measles, diphtheria, pertussis, and a variety of respiratory viral infections. Of note, is that pandemic influenza A (H1N1) 2009 is currently circulating in Haiti. Meningococcal disease also may spread under these conditions. Of great concern in conditions of crowding is tuberculosis, which, in 2007, had an incidence of 147 cases per 100,000 population. Approximately 4,000 patients were receiving treatment for tuberculosis in Port-Au-Prince at the time of the earthquake. Many with tuberculosis are coinfected with HIV.

Vector-borne diseases also may pose a risk, especially with the population abandoning their homes for fear of aftershocks and living in the streets. West Nile virus has been detected in Haiti. All four dengue types are endemic in Haiti, where transmission mainly occurs during April through November. Malaria, however, is transmitted year round throughout the country. Only Plasmodium falciparum is present; it has been considered to always be susceptible to chloroquine, and failures of treatment with this drug have not been reported. However, mutations in the pfcrt gene associated with chloroquine resistance were recently identified in some isolates obtained in the Artibonite Valley.1 Lymphatic filariasis is common. Zoonoses of concern include leptospirosis and rabies. A program of mass rabies vaccination of dogs was in progress at the time of the earthquake.

WHO has enunciated a set of priority interventions for immediate implementation (see Table 2).

Table 2

An element to consider with regard to essential emergent medical and surgical care is appropriate triage. Contaminated or infected wounds or those present for more than six hours should not be closed. Patients with wounds should be given tetanus prophylaxis. Standard infection control precautions should be maintained. Post-exposure prophylaxis should be available for health care, rescue, and other workers. Protection of the blood supply must be maintained. Measures must be taken to prevent interruption of treatment of patients with tuberculosis, HIV, and chronic non-infectious diseases, such as diabetes mellitus. Provisions for mental health and psychosocial support must be made available.

Measles vaccination is an immediate priority for children aged 6 months to 14 years living in crowded or camp settings, regardless of previous vaccination or disease history. Supplementation with vitamin A should be administered to children six months through 59 months of age. Mass tetanus vaccination is not indicated. Hepatitis A vaccination can be considered, and typhoid vaccination may be useful for control of outbreaks.

Large numbers of medical and other workers are entering Haiti to provide relief services. Guidance regarding personal measures for individuals planning on volunteering are addressed in this WHO document, but a more extensive set of recommendations has been posted by CDC.2

A medical correspondent on CNN warned of the danger of unburied corpses. As it has indicated before, WHO states, "It is important to convey to all parties that corpses do not represent a public health threat. When death is due to the initial impact of the event and not because of disease, dead bodies have not been associated with outbreaks. Standard infection control precautions are recommended for those managing corpses."

Reference

  1. Londono BL, et al. Chloroquine-resistant haplotype Plasmodium falciparum parasites, Haiti. Emerg Infect Dis. 2009;15:735-740.
  2. CDC. Guidance for Relief Workers and Others Traveling to Haiti for Earthquake Response. http://wwwnc.cdc.gov/travel/content/news-announcements/relief-workers-haiti.aspx