This is the VOA Special English DEVELOPMENT REPORT.
Up to five-hundred-million people are infected each year with a disease called leishmaniasis (LEASH-ma-NIGH-a-sis). Most of the victims are young children in poor countries. An organism called the leishmaniasis parasite causes the disease. It is spread by the bite of a sandfly. The insect passes the parasite from dogs to humans.
Recently, a study found that children could be protected from visceral leishmaniasis if dogs wear collars with chemicals to guard against insect bites. Dog collars are worn around the neck. They usually are made of metal or animal skin.
There are four forms of leishmaniasis. Visceral leishmaniasis causes high body temperature. It also can affect some organs of the body. Victims may not produce enough white blood cells. The disease will kill if it is not treated. Most victims of visceral leishmaniasis are in Bangladesh, Brazil, India, Nepal and Sudan.
In the study, research scientists from Britain and Tabriz University in Iran studied eighteen Iranian villages during a period when leishmaniasis often is spread. The researchers gave chemically treated collars to dog owners. After one year, the researchers tested dogs and children in all the villages for the parasite, known as Leishmaniasis infantum. The infection rate was cut by fifty-four percent in dogs. The rate in children dropped by forty-two percent.
Using chemically treated dog collars is one of several ways to control the spread of leishmaniasis. One method is to cover or spray houses with chemicals designed to kill insects. Another way is to destroy dogs without owners and other animals that show signs of the disease.
These methods are reported to have helped in China. However, they have not been very effective in other areas. In Brazil, for example, the number of leishmaniasis cases has risen slowly during the past twenty years. The researchers report that two-hundred-thousand homes in Brazil were sprayed and twenty-thousand dogs destroyed each year during this period.
The World Health Organization estimates that twelve-million people are infected with leishmaniasis worldwide. The W-H-O estimates that at least three-hundred-fifty-million people in eighty-eight countries may be at risk of infection.
This VOA Special English DEVELOPMENT REPORT was written by Jill Moss.