Guest blog by David M. Olson, MD, Medical Advisor, Médecins Sans Frontières/Doctors Without Borders (MSF), New York, NY, USA
This week I have been called back to Haiti because of the cholera epidemic that first hit in late October and which continues to have a devastating effect. At the time of writingthis post, more than 1,100 people have died and over 18,000 hospitalizations due to cholera have been reported throughout the country.
The main priority for MSF, at this time, is to treat and manage patients in cholera treatment centers (CTCs) and on an outpatient basis. Patients with cholera can die within hours due to severe dehydration from voluminous diarrhea and vomiting. Treatment for cholera is relatively simple: intravenous fluids (ie, Ringer’s lactate solution) for the most severe cases, and oral rehydration solutions (ORS), comprised of glucose and electrolytes, for those who can drink and keep down fluids.
In recent weeks, the outbreak has spread to the area of the capital, Port-au-Prince, where the risk of transmission is high due to concentrated populations in unsanitary conditions. Because cholera has not been seen in Haiti for several decades, the country’s population has had no previous exposure to cholera bacteria and is thus relatively vulnerable to infection.
The strain of Vibrio cholerae bacteria identified in Haiti, the O1 El Tor biotype, was found to be most similar to strains from South Asia, which have also been seen in outbreaks elsewhere. In the 2008-2009 cholera outbreak in Zimbabwe, this V. cholerae strain was isolated and shown to be resistant to fluoroquinolones (antibiotics), the first such report in Africa. With our colleagues in Nigeria and Cameroon and the Pasteur Institute, we also reported the presence of this fluoroquinolone-resistant strain in the 2009 cholera epidemic in western/central Africa.
The isolation of this particular strain in different epidemics is not unexpected. Cholera is endemic in many countries all over the world, and these outbreaks can be seen as part of an ongoing, decades-long global pandemic. The current global pandemic (seventh recorded) began in 1961, affecting countries worldwide. Last year, outbreaks also occurred in Zambia and Papua New Guinea, and other outbreaks are currently ongoing in Pakistan and again this year in western and central Africa, killing more than 2,000 people and involving more countries than in 2009 (Nigeria, Cameroon, Niger, Chad). What is happening now in Haiti, as well as in Africa and Asia, may thus be part of the seventh global pandemic.
Where the cholera strain arose from may never be known and is a moot point, given that the priorities should be treating the patients now in the CTCs and the prevention of further cases. Clean water, proper sanitation, and good hygiene practices are all that is needed to prevent cholera. It must be kept in mind however that access to clean water or sanitation is difficult to come by at this time in Haiti and other at-risk areas (eg, Pakistan’s flooded areas). For the time being, cholera infection risk remains high, and immediate medical attention is essential.
Cholera vaccination is a potential avenue of medical response, but seemingly not a feasible option at this time. Currently WHO/PAHO does not recommend the use of cholera vaccination in Haiti as an emergency response. Focus is currently on case management, though as conditions change, vaccine use may be advisable. A number of issues make vaccinating during an outbreak particularly challenging, including administration (requires two oral doses a week apart), duration of protection, lack of licensed use in children <2 years old, storage requirements, and cost. Also, the global cholera vaccine supply cannot currently meet the huge needs in Haiti, where millions of people are at risk.
As cholera infections continue in Haiti, protests from the population in some areas have led to delays or cancellations in setting up new CTCs. The panic and frustration from local populations are understandable. Even with the “simple” medical solutions of oral and intravenous rehydration, our CTCs are busy, as we deal with issues of space, human resources, and a moving epidemic. Support from other aid actors is urgently needed to fully cover other aspects of cholera control, namely safe water distribution, health promotion, oral rehydration points, and waste management and disposal.