The new patch, developed by U.S. biotechnology company Iomai Corp., has been found to reduce the likelihood of contracting traveler's diarrhea among people going to high-risk areas like Mexico.
Even when people developed diarrhea while wearing the patch, the condition was less severe and the agonizing episode shorter, the researchers said. Travel diarrhea affects nearly 27 million travelers and 210 million children each year, often from eating contaminated food or drinking contaminated beverages.
The diarrhea usually lasts about four to five days; symptoms include loose stools, nausea, vomiting, abdominal pain, and dehydration and its main cause is enterotoxigenic E. coli bacteria. The disease is responsible for some 380,000 child deaths.
Two doses of the vaccine are needed to make it most effective and it is most effective when given two weeks before traveling. In this phase II trial, 178 people planning trips to Mexico or Guatemala were randomly assigned to the vaccine patch or placebo patches.
The researchers from the University of Texas School of Public Health in Houston found that 24 of the 111 travelers who received placebo had travelers diarrhea, of these 11 had diarrhea caused by E. coli.
However, among the 59 travelers who received the vaccine, 12 had bouts of diarrhea, but only three had diarrhea caused by E. coli. The report is published in the June 12 online issue of The Lancet.
However, the researchers added that the vaccine still needs to go through a large phase III trial. If the trials are successful, the vaccine could be available to the public by 2011.
