Growing Rice and a Cholera Vaccine at the Same Time　(2/2)

People would take the vaccine as a drug that contains the powder. Cholera is usually spread through water or food, in places where conditions are dirty and drinking water supplies are unsafe. Cholera infections are often mild. But some people develop severe cases. The World Health Organization says half of them will die if they are not treated.

The researchers say the experimentalcholera vaccine produced reactions in the immune system and in areas of mucosaltissue" class="hjdict" word="tissue" target=_blank>tissue. Mucosal surfaces include the mouth, nose and reproductive organs. Cholera as well as viruses like those that cause influenza " class="hjdict" word="influenza " target=_blank>influenza and AIDS infect these areas.

The scientists have great hopes for rice-based vaccines as a way to protect large populations against mucosal infections. There would be no need for injection, since the vaccine would be taken by mouth.

Yet scientists have tried for some time to make plant-based vaccines. Researchers in the United States have developed one for Newcastle disease in chickens, but so far there are no products for humans. At the same time, scientists have to deal with concerns about genetically engineered plants accidentally mixing with food crops.