Oral polio vaccine causes Hispaniola outbreak

By SUSANNAH A. NESMITH, Associated Press

SANTO DOMINGO, Dominican Republic (December 3, 2000 5:53 p.m. EST http://www.nandotimes.com) - A mutated polio vaccine has infected at least three people in the Caribbean nations of the Dominican Republic and Haiti, causing the first outbreak of the disease in the Western Hemisphere since 1991, the Pan American Health Organization said.

The outbreak has raised serious concerns because it has been traced to the same oral vaccine that experts have used to eliminate the disease in many countries, said a statement released Saturday by the organization, which is a part of the Washington-based Organization of American States.

But it said the standard vaccine appears to still work against the mutated strain, and its experts are helping organize vaccination efforts in Haiti and the Dominican Republic, the two countries that make up the island of Hispaniola.

Polio is a highly infectious disease that usually strikes children under 5. It damages the spinal cord and brain, causing paralysis and sometimes death.

In the Dominican mountain town of Constanza, where the first case was reported, officials at the local hospital said they have been swamped by people seeking vaccinations.

"Everyone here is worried," hospital director Jose Matos Perez was quoted as saying in Listin Diario newspaper. "Everyone wants to vaccinate their children, including many with children that are over five years old."

Visitors to both countries should make sure they are vaccinated, the health organization said.

The last case of polio in the Americas was diagnosed in Peru in 1991.

The organization said laboratory tests had confirmed two cases in the Dominican Republic and one in Haiti since July, and doctors were investigating 16 other patients suffering polio-like paralysis. The statement did not describe the state of health of those infected.

The vaccine, known as Sabin 1 oral poliovirus vaccine, uses a weakened version of the virus to teach the body how to identify and fight active viruses.

The mutated virus is 97 percent identical to the one used in the vaccine, the organization said.

The health organization believes that the three infected people may have caught the mutated strain from someone else. That person - or persons - may have received a standard vaccination that mutated within them; they then may have passed it to the infected people, who were living in an area where few people have been vaccinated.

The only other known case of an oral vaccine mutating into a virulent strain was in Egypt between 1983 and 1993, the organization said. More than 30 people were infected with that strain.