Mind & Body
Study: U.N. Projections of Cholera Inaccurate
- Tuesday, April 12, 2011 4:07 PM
A study conducted to determine the spread of cholera in Haiti, by the University of California (UCLA) and Harvard Medical School determined that the United Nations (UN) critically underestimated the epidemic. The UN projected 400,000 while the academic report by the universities determined the number to be twice that. The U.N. estimates are critical because those are used to determine how resources are allocated.
The study published by Jason Andrews M.D. and Sanjay Basu, M.D. projected 779,000 cases of cholera and 11,000 deaths between March 1st and Nov 30, 2011, nearly 10% of the population.
The two also believe that Haitians must take a long term approach for curbing the epidemic. Basu told the LA Times "the epidemic is not likely to be short-term" and his colleague Andrews said "it is going to be larger than predicted in terms of sheer numbers and will last far longer than initial projections."
United Nations Estimated on Assumption
In October, the U.N. projected that 200,000 people would eventually become infected, and then two weeks later it doubled that projection to 400,000.
According to Basu, however, the U.N. made its estimate based on the assumption that the disease would infect 2 percent to 4 percent of Haiti's population of 10 million people. Basu and Andrews said the U.N. estimates did not incorporate existing disease trends or take into account major factors, such as where water was contaminated, how the disease is transmitted or even human immunity to cholera.
Using data from Haiti's Ministry of Health and other sources, Andrews and Basu made a more sophisticated model of the spread of disease in several Haitian provinces. The results led them to predict that 779,000 Haitians would contract the disease and about 11,100 would die in the next eight months.
Vaccination to Save Lives
The Basu-Andrews report included estimates on the effectiveness of what Haitian authorities and the international community have undertaken in providing uncontaminated water. The doctors' report says that 105,000 of the roughly 800,000 expected cases could be averted by providing 1% of the population with uncontaminated water.
The major suggestion of the report is the use of vaccines and antibiotics to thwart the spread and heal the patients of the disease.
Dennis Chao of the Fred Hutchinson Cancer Center in Seattle, Washington , along with 3 other colleagues agreed with the Basu-Andrews report.
Chao's research paper , published by the Proceedings of the National Academy of Sciences, found that vaccinating 5% of the population would reduce the number of cases by 11%. 30%, double-vaccines, would reduce the cases expected by 55%, saving 3,320 lives.
Sanjay Basu, speaking in the LA Times articles said, the beauty about vaccines and antibiotics is they not only help the person who received them, but they reduce the transmission of the disease to others.
Dennis Chao, in a Nature News article said that there are not enough doses in the world to provide it for the population of 10,000,000 in Haiti.
Carolina Danavar, the Regional Immunication Adviser for the Pan American Health Organization (PAHO) said in the same article that "at the beginning of the epidemic, vaccination was considered, but given the limited global vaccine supply and other issues [such as fairness], cholera vaccinating was not considered practical."
David Sack a vaccine expert at John Hopkins University, Baltimore, Maryland said stockpiles of the vaccine are available but limited as the World Health Organization (WHO) seeks to determine how many are available and should be kept in supply.
Sack placed blame on the United Nations, saying their fault estimates hindered the organization's preparedness. Sack said "had the UN ordered the production of vaccines back in October, there would have been enough for use in high-risk areas, there would not have been a problem of limited supply."
The United Nations, through MINUSTAH, has been accused for causing the outbreak, for dumping waste from a Nepalese Station into the water supply. Many independent scientist and doctors have identified the cholera strain in Haiti to be from South Asia. For the UN's part they have sent an investigator to the island and await the investigator's report.