Progress in search for dengue vaccine

Besides French and American researchers, Thai scientists have now also said that they have developed a prototype vaccine that can soon be tested on humans.

Science and Technology Minister Virachai Virameteekul said the vaccine’s development marked a major step in overcoming the spread of the dengue virus. Initial laboratory tests on mice achieved an 80 percent prevention rate.

Virachai went on to say that it was a very big step in science and the accumulation of Thai research over the past 20 or 30 years.

Over 100 countries afflicted

There are four strains of the dengue virus which is found in over 100 countries from Africa, the Americas, the eastern Mediterranean, South East Asia and Western Pacific. The World Health Organization says up to 50 million people fall ill from the disease each year.

While most people face only mild effects from the virus, when complications arise, it can lead to the more deadly haemorrhagic fever.

Experts from Chiang Mai University, National Centre for Genetic Engineering and Biotechnology and Mahidol University created a hybrid virus known as a Chimeric Live-attenuated vaccine using genetic engineering to match the four strains of the virus.

Big challenge

Mahidol University professor in molecular biosciences, Prasert Auewarakul, says getting the right balance within the vaccine to match the four serotypes of the virus was a challenge. "The challenge is for this type of technology, the live attenuated vaccine, is you need to have four viruses that are almost equally good in replicating inside the human body. So you need to balance the four vaccines very carefully so they are equally strong in terms of replicating in the body."

Individuals are only immune to the type of dengue virus they are infected with. If a person becomes ill with another type of dengue their medical condition becomes far more serious. Most vulnerable are children who have no immunity and can die within days of infection.

Dr. Boonsook Keelapang, a researcher from Chiang Mai University, says improving the health safety of children is a vital outcome of the research. "It is important because if we succeed we can help our children in our country because dengue is the (major) disease affecting the Thai people and all the people in South East Asia and we need all the power and help to make it work."

Affordable vaccine

Key to bringing the vaccine to the market is a 100 million dollar investment by privately owned bio-technology company, Bio-Net Asia. Company president Vitoon Vongsangool told Deutsche Welle, "We are unlike a multinational. We want to make the vaccine affordable. When you make it affordable you get more in terms of volume."

Rising global temperatures are hastening the spread of the dengue virus. The market for the vaccine will reach from India to China throughout all of South East Asia and even into northern Australia.

Author: Ron Corben (Bangkok)
Editor: Sarah Berning