Painless Vaccines

By Nancy Steinbach

This is the VOA Special English Science Report.

Every year, millions of children and adults are given vaccine medicines to prevent disease. These vaccines are injected into the body using a needle. However, some people do not get vaccines because they fear needle injections. Or the injections are too costly or too difficult to give. Medical researchers hope to change this by developing vaccines that can be given without a needle.

The latest new vaccine could be placed on the skin for a few hours. A team at the Walter Reed Army Institute of Research in Washington, D-C studied the possibility of such a vaccine a few years ago. They experimented with mice.

The scientists placed a liquid on the animals' skin. The liquid contained proteins that were part of vaccines against the diseases diphtheria or tetanus. The liquid was mixed with poison produced by the bacteria that causes the disease cholera.

The cholera toxin was given to strengthen the body's defense system against whatever disease proteins were given along with it.

The mice developed antibodies in their blood to fight against both diphtheria and tetanus. They did not develop cholera. Gregory Glenn was part of the Walter Reed medical research team. He is now the scientific director of the Iomai Company in Washington, D-C. The company is developing this new kind of vaccine. Recently, the scientists reported about their work in the publication "Nature Medicine."

They said small pieces of material containing a vaccine could cause strong defense reactions in people when placed on the skin. These pieces of material are called skin patches. The researchers said using skin patches could probably protect people against many kinds of diseases. Early tests on people seem to show the method is safe. The company plans tests on more people. It expects results some time next year.

Medical experts say the vaccine patch could be most important in developing countries. It could be the least costly way to reduce disease and infection rates. Using a vaccine patch avoids the problems of safely storing and using vaccines and needles. And it could be a good method for vaccinating large numbers of people. It would reduce the number of medical workers and material required for mass immunizations.

This VOA Special English Science Report was written by Nancy Steinbach.