Researchers in the US have found promising results from clinical trials on a new dengue vaccine. A dengue vaccine developed by US National Institutes of Health scientists protected everyone given the shot against the virus. The vaccine is very effective at preventing the deadly infection and is likely to require only a single dose. The researchers said it could become widely available by 2018.
Dengue fever produces a high fever, rash and joint pain, but may also cause hemorrhage and shock, as well as death. It affected nearly one lakh people in India last year. Development of vaccines for dengue has been complicated. Since the disease can be caused by any of four dengue virus serotypes and the vaccine must be tetravalent providing equal protection against all four serotypes researchers said.
Scientists from University of Vermont or UVM, National Institute of Allergy and Infectious Diseases (NIAID) and Johns Hopkins Bloomberg School of Public Health in the US gave volunteers a vaccine or placebo and tested for protection against a weakened strain of dengue that causes infection, but no or minimal symptoms.
Results of the research in the US showed that all vaccinated volunteers were protected from the “challenge” virus, but none of the volunteers receiving placebo vaccines were protected. The vaccine was well-tolerated in all volunteers. “This work used a robust method which predicts a high likelihood of success for this critically important dengue vaccine,” Beth Kirkpatrick from UVM said.
“Control of dengue has certainly been a public health priority for many years, but getting there hasn’t really been very easy,” said virologist Stephen Whitehead of the NIH’s National Institute of Allergy and Infectious Diseases, who spearheaded the development of the vaccine. The vaccine was made from a mixture of four live, weakened viruses targeted to each of the four different strains.
The results were very promising and inspired “great confidence” that the vaccine will protect people in areas where dengue is endemic. Dengue, found in the world’s tropical and subtropical regions, infects nearly 400 million people in more than 120 countries annually. Most survive with few or no symptoms, but more than 2 million people annually develop dengue hemorrhagic fever, which kills more than 25,000 people each year.