There is a new weapon in the drug arsenal against rotavirus diarrhea, an often-deadly disorder for infants in poor countries as the result of dehydration. The medication can be an important backup for new rotavirus vaccines expected to become available within a decade.
Diarrhea is among mankind's most common ailments. One-fourth of the world's population suffers it every year. The form of the illness caused by the rotavirus has enormous medical and social costs. Roughly 500,000 young children die from it annually in developing countries, while in industrial nations, one in 40 children are hospitalized.
Although effective vaccines have recently been developed to prevent the virus, there has been no effective treatment for people suffering it. Now, a study published in the medical journal Lancet shows that a drug used for several years against a form of diarrhea caused by a parasite called cryptosporidium also works against rotavirus and other viral diseases of the gut. The drug is nitazoxanide, available under the brand name Alinia from Romark Laboratories.
"It has been an anti-diarrheal from the beginning," said nitazoxanide study leader, physician Jean-Francois Rossignol of the Romark Institute for Medical Research in Tampa, Florida. "We knew it was working extremely well in diarrhea, but the only proof we had at the time were the anti-parasitic effects. By accident we discovered about two years ago that this was a broad spectrum anti-viral."
Rossignol and Egyptian and Italian colleagues tested nitazoxanide in babies suffering life-threatening rotavirus diarrhea in Cairo. Among 50 children admitted to Cairo Children's Hospital, infants who received nitazoxanide took an average of 31 hours to recover compared to 75 hours for a placebo group.
"We discovered that the drug was not only very effective, but very well tolerated by babies who were vomiting and with intensive dehydration due to massive diarrhea," he added. "In the developing world, the first thing you want to do if you develop a drug is safety because the health care system is not really able to cope with side effects of drugs."
In addition to nitazoxanide, two new oral rotavirus vaccines from the pharmaceutical companies Merck and GlaxoSmithKline have been very effective in South American tests. Experts at this week's International Rotavirus Workshop in Lisbon say they could become available to all children worldwide in 10 years. Rossignol says the vaccines will become the first line of defense against rotavirus diarrhea. But he points out that nitazoxanide will be necessary as a backup, because the vaccines may prove less effective in parts of Africa and Asia where malnutrition and other conditions might interfere with their immune response.
"You have to have a drug because some patients are going to be sick with the vaccine and some others are not going to get the vaccine," he explained.