samedi 18 août 2012

WHO Calls For Emergency Stockpile Of Cholera Vaccine

by RICHARD KNOX A month ago the results of a successful cholera vaccine project in Haiti became available. Now the World Health Organization is calling for the establishment of a global stockpile of the vaccine to respond to outbreaks like Haiti's. The WHO's technical advisers cited the recent Haiti vaccination project, involving 100,000 people in Port-au-Prince and a rural area, as evidence that cholera vaccination can work in the midst of an outbreak — a proposition that has engendered controversy since Haiti's epidemic began in late 2010. Critics argued that vaccination would distract from treating cholera victims. Moving with unusual speed, the WHO is seeking funds to launch the stockpile, which would initially contain enough doses to vaccinate a million people and cost $10 million a year to maintain. The vaccine costs $1.85 a dose, and two doses are needed over a few weeks' time to achieve 60 to 85 percent protection. But it's clear the WHO envisions a much bigger stockpile down the road. "As manufacturers ramp up production in the near future, the experts unanimously recommended moving toward universal vaccination," the WHO and its sister organization the Pan American Health Organization said in a statement. Universal cholera vaccination in Haiti would require almost 20 million doses. That in itself would not eliminate cholera there, but the experts now agree that vaccination would help curb the illness, along with programs to increase access to clean water and sewage treatment. More than a half-million Haitians have been infected with cholera since 2010, and more than 7,400 have died from the disease. The neighboring Dominican Republic has reported more than 25,000 cases and over 400 deaths. And this summer, Cuba began to see cholera cases for the first time since it was a Spanish colony in the 1800s. The chairman of the WHO technical advisory group, Dr. Ciro de Quadros, called the results of the Haitian demonstration projects "highly impressive" and said they "really provide a road map for what we can do in the near future." The group met earlier this week in Washington. The deputy director of PAHO, Dr. Jon Andrus, who was initially skeptical of using oral cholera vaccine during an outbreak, opened this week's meeting by saying that if the evidence warrants it, "we should not fail to miss short-term opportunities to save lives more quickly." On the advice of PAHO, Haiti decided against cholera vaccination after the disease was introduced, most likely by United Nations peacekeeping forces from a cholera-endemic area. The Centers for Disease Control and Prevention in the U.S. has also been highly skeptical of the vaccine's role. But some public health advocates were convinced that vaccination could make a difference, and pushed WHO and PAHO to reconsider. In mid-2011, the World Health Assembly (the WHO's governing body) called for more effective cholera control, including the use of cholera vaccine "where appropriate." And last year, the WHO approved a cheaper and easier-to-use oral vaccine called Shanchol, which was used in the Haitian demonstration project this spring. Against this backdrop, advocates of cholera vaccination in Haiti realized it would be crucial to show the feasibility of cholera vaccination in settings where at-risk populations are hard to reach, need to understand vaccination, and must return for a second dose. Government officials also had to be convinced that the enterprise was praticable. The mass vaccination campaigns in Port-au-Prince and the Artibonite River valley weredelayed by false reports that the vaccine was experimental. That required more review by a government-appointed ethics committee, pushing the launch date into Haiti's rainy season, when cholera incidence spikes and the logistics of vaccination become difficult. But in the end, more than 90 percent of vacinees returned for a second dose. A similar recent experience during a cholera epidemic in the West African nation of Guinea buttressed the case that the vaccine is deliverable in difficult situations. Dr. Louise Ivers of Partners in Health, which sponsored one of the Haitian demonstration projects, told Shots in an email that the organization is gratified that WHO has decided to include vaccination in the toolkit of anti-cholera measures. "While currently available cholera vaccines are not golden tickets, we must move quickly to save as many lives as we can with the tools that are available to us now," Ivers said http://www.npr.org/blogs/health/2012/08/17/159014069/who-calls-for-emergency-stockpile-of-cholera-vaccine

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