Vietnam is expected to generalize the first-ever vaccine for the mosquito-borne disease dengue fever, after the completion of its experimental phase, according to the local drug administration.
In order for the new vaccine to be circulated, the antigenic substance must first go through clinical trials, the Drug Administration of Vietnam said.
According to Phan Trong Lan, director of the Ho Chi Minh City Pasteur Institute, Vietnam is among five Asian nations to take part in the trial of the dengue fever vaccine.
The Southeast Asian country is in the third phase of the experimental process, during which the effectiveness of the vaccine is evaluated, Lan said.
During this stage of the drug’s development, over 2,300 children between the age of two and 14 in My Tho City, Tien Giang Province and Long Xuyen City, An Giang Province, both in the Mekong Delta, volunteered to go through the trials.
The combined result of these trials in both Asian and South American countries showed that the success rate in terms of prevention of dengue was 66 percent for children above nine years old, minimizing harm in 81 percent of dengue fever cases that required hospitalization and in 93 percent of more severe cases, Lan elaborated.
In children below the age of nine, the vaccine proved less effective, with a prevention rate of only 44 percent, minimizing harm in 56 percent of patients that required hospitalization and 67 percent of even more serious cases.
However, Tran Dac Phu, head of the General Department of Preventive Medicine under the Ministry of Health, was cautious in his assessment of the new dengue fever vaccine.
“Dengue fever bears the heaviest burden amongst epidemics in Vietnam. There are approximately 100,000 people infected with the disease and dozens of fatalities each year,” Phu said.
The application of the antigenic substance must be carried out on a large scale, after thorough studies in terms of safety and effectiveness are conducted, according to the health official.
He expected that the cost of the vaccine will not make it affordable to everyone with an anticipated price worldwide of US$50 per shot, adding that a person must be injected with a total of three shots at six-month intervals.
The vaccine will not be provided free of charge as it is not included in the country’s expanded program of immunization, Phu continued.
“If the vaccine is effective, I believe that local authorities will provide the injection free-of-charge for poorer people,” he said.
Dengue fever is an infectious disease transmitted by the bite of an Aedes mosquito that has been infected with the dengue virus, with symptoms including high fever (39 degrees Celsius or higher), headaches, muscle and joint pains, and a skin rash similar in characteristics to measles, according to the World Health Organization (WHO).
The disease is considered epidemic in 128 countries. The prolonged El Nino phenomenon between 2014 and 2016 in Vietnam is thought to have increased the risk of outbreaks.
Various vaccines against the disease have undergone 20 years of research in 17 nations.
The WHO has recently approved the use of the vaccine, with Mexico, Brazil, El Salvador and the Philippines all preparing for its production and application.