PORT-AU-PRINCE, Haiti, March 26, 2015 (AMG) — An oral cholera vaccination campaign carried out across rural Haiti was effective, according to a study led by Harvard Medical School researchers at Partners In Health.
The campaign: The study, published in the March issue of The Lancet Global Health, found there were 63 percent fewer cases of cholera among those who received the vaccine than those who did not. The vaccine was given to 45,417 people in the Artibonite Department with 91% receiving both oral doses two weeks apart.
Recipients were shown to be protected for between 4 and 24 months after the campaign began. The intervention was carried out by Partners In Health and its sister organization, Zanmi Lasante, with the full cooperation of Haiti’s Ministry of Health between April and June 2012.
Why is this significant?: There are currently two cholera vaccines considered safe and effective by WHO; Shancol, developed by the Indian company Shantha Biotechnics and the one used in this campaign, and the Swedish developed Dukoral. These have both been used before in countries where cholera is endemic – a constant threat in people’s lives – but rarely in severe outbreaks such as in Haiti due to insufficient evidence if its effectiveness.
The real-life constraints that initially accompanied the chaos of Haiti’s broken health system, lack of medical personnel and limited time to inform the public were thought by some skeptics as too challenging to run an effective vaccination campaign. The official guidance that treatment and clean water and hygiene initiatives are key to fighting cholera is unchanged, however, this latest study adds to growing evidence that it is possible to vaccinate large numbers of people in a short time with encouraging results.
Louise Ivers, Associate Professor of Global Health and social medicine and a Senior Health and Policy Adviser at Partners In Health says, “we undertook the campaign as a public health emergency, but having data to demonstrate how effective it was helps to solidify the case for using vaccines in this kind of setting—and that helps transfer lessons from Haiti to other places where cholera occurs or may appear for the first time.”
Questions still to consider before rolling the intervention out nationally include how effective one dose of vaccine is compared to two, its safety during pregnancy and its stability in a tropical climate.
The epidemic now: Until October 2010, ten months after the devastating earthquake, cholera had not been recorded in Haiti for at least 150 years. It has now been reported in all 10 departments. The porous border between Haiti and the Dominican Republic led to cholera’s emergence there the following month, and by 2014 it had reached Cuba, Mexico and Puerto Rico, but not with the same ferocity as where it began. Haiti’s woefully unprepared health system and lack of infrastructure propagated an outbreak that to date has infected around 720,000 people and killed over 9,000.
Despite evidence linking the epidemic to the United Nations Stabilization Mission in Haiti, who were deployed from Nepal where cholera is endemic, they have continued to deny any legal responsibility. Haiti has launched another lawsuit against the UN, having been told in January that the organisation is immune from liability. On March 11, 1,500 Haitian victims and their families sued the international body in a federal court in Brooklyn in a class action.
As the fight for compensation and culpability continues, efforts to control the epidemic are ongoing. In December last year, the Chilean government contributed US$300,000 towards Haiti’s fight, specifically towards the vaccine campaign.
Following last year’s rainy season, the International Committee of the Red Cross vaccinated over 5,780 prisoners. Over five years since the greatest natural disaster in Haiti’s living memory, these latest findings give hope to a nation struggling to get back on its feet.
Cover image: CDC Global