They are normally transmitters of the disease, but mosquitoes could one day be used to tackle malaria after scientists developed a genetically engineered version of the species that can deliver a vaccine.

Researchers altered the salivary glands of the Anopheles stephensi mosquito, dubbed a "flying vaccinator," so that it carried the Leishmania vaccine within its saliva.

This mosquito, the main spreaders of human malaria, was shown in tests to transmit this vaccine when it bit its host, in this case laboratory mice, making it a transmitter of the vaccine.

Bites from the insect succeeded in raising antibodies in the mice, indicating successful immunization with the vaccine, according to research published in Insect Molecular Biology, a British scientific journal.

The study, led by Associate Professor Shigeto Yoshida from the Jichi Medical University in Japan, could be used to formulate a new strategy in the global fight against malaria.
"The lack of an effective malaria vaccine means control of the carrier has become a crucial objective to combating the disease. Following bites, protective immune responses are induced, just like a conventional vaccination but with no pain and no cost," said Yoshida.

"What's more, continuous exposure to bites will maintain high levels of protective immunity, through natural boosting, for a lifetime. So the insect shifts from being a pest to being beneficial."

About 60 species of the Anopheles mosquito are vectors of the malaria parasite, which are transmitted to humans when the female feeds on blood. Every year about 250 million people are infected with malaria and nearly one million die, according to the World Health Organization.

In Africa one in every five childhood deaths is caused by malaria, says the WHO.

However, the researchers admit that there are barriers to using this form of vaccination in the wild, including issues of controlling dosage, "medical safety issues" and the "issues of public acceptance to the release of transgenic mosquitoes."
SOURCE:London, England (CNN)

New malaria vaccine found safe for children

A new vaccine has shown promise in protecting the most vulnerable patients -- young children -- against malaria, says a study.
Researchers found the vaccine stimulated strong and long-lasting immune responses in Mali children. Actually, the antibody levels the vaccine produced were as high or even higher than the antibody levels found in adults who have naturally developed protective immune responses to the parasite over lifelong exposure to malaria.

"The findings imply that we may have achieved our goal of using a vaccine to reproduce the natural protective immunity that normally takes years of intense exposure to malaria to develop," says Christopher V. Plowe, Professor at the Centre for Vaccine Development (CVD), Maryland University.
Plowe, who led the study, is also an investigator with the Howard Hughes Medical Institute and a Doris Duke Distinguished Clinical Scientist.

In places like Africa, where malaria is particularly rampant, the young are most vulnerable to the disease since they have not built up the same natural immunity as adults. A child dies of malaria every 30 seconds, according to the World Health Organisation.

There are about 300 million malaria cases worldwide each year, resulting in more than one million deaths, most of them African children, says a CVD release.

The new vaccine, called FMP2.1/AS02A, was developed as part of a longstanding research collaboration between the Walter Reed Army Institute of Research (WRAIR) GlaxoSmithKline Biologicals (GSK). "There is a large economic cost and a human cost," said Debra Lerner, Director of the Institute for Clinical Research and Health Policy Studies at Tufts Medical Centre, who led the study.

 Source: Daily Mail