Dengvaxia helpful if 'used properly': infection specialist

ABS-CBN News

Posted at Aug 08 2019 08:45 AM | Updated as of Aug 08 2019 09:02 AM

Watch more in iWant or TFC.tv

MANILA - An infection specialist on Thursday said the controversial Dengvaxia vaccine will help in future dengue epidemics if "used properly."

"The scientific evidence is overwhelming that this will be useful for patients who have already had dengue, or patients who actually did not finish their series of 3," Dr. Edsel Maurice Salvana told ANC's Early Edition.

Government has declared a national dengue epidemic after recording 146,062 cases of dengue, with 622 deaths as of July 20. The figure is double from the 73,818 cases recorded during the same period last year.

Salvana, director of the Institute of Molecular Biology and Biotechnology at the National Institutes of Health, agreed with health officials that the vaccine would have "minimal impact" on the current dengue epidemic, but it would have made a difference if the vaccine was used 6 months ago.

"It’s not an epidemic response vaccine in the sense it takes a while for vaccines to work. In the case of Dengvaxia, you need 3 doses before we know it has efficacy," he said.

"But because in the Philippines dengue transmission is ongoing year-round, if you decrease the number of people who are susceptible to dengue then you can also decrease the overall burden of infection."

The government doctor added that there's "no reasonable scientific argument" for government not to lift its ban on Dengvaxia, citing the approval of the European Union (EU) and the United States Food and Drug Administration (FDA), which he said was "one of the most stringent in the world."

"As doctors, as the medical society that are directly treating the patients, if the US FDA and EU have already approved a drug for use, as long as we use properly, there’s no reasonable scientific argument not to use it," Salvana said.

"They will not approve a vaccine if they have significant safety concerns and significant efficacy concerns."

The government in late 2017 stopped giving the world-first vaccine to schoolchildren after drug maker Sanofi disclosed that it may cause more "severe" symptoms among those who have not had dengue.

"They did an additional study to determine that in patients who have not had dengue before, the risk increases from 2 out of 1,000 to 5 out of 1,000, same as that of somebody who has already had dengue once and did not get the vaccine," Salvana explained.

The French firm appealed last month the revocation of Dengvaxia's certificate of product registration.

LINK TO DEATHS?

Salvana said there's no proof yet that the controversial vaccine is linked to deaths.

"As far as we know, the only way Dengvaxia is linked to an increase of death is if somebody who did not have dengue gets Dengvaxia and then dies from dengue," he said.

"It doesn’t cause death in and of itself, but it can increase the risk to 5 out of 1,000, which is the same as that of somebody who has had dengue before but did not get the vaccine."

Salvana added that those who examine the patients who allegedly died from the vaccine must be forensic pathologists and not forensic specialists.

"The Public Attorney's Office doctor is not a forensic pathologist. He’s a forensic specialist. The Philippine Society of Pathologists has commented that is very inappropriate to make conclusions by gross findings and these need to corroborated by tissue diagnostics," he said.

"You cannot make conclusion based on what we call gross or what you can just see by your eye, you cannot say anything just by looking at the organs."

Reports of alleged deaths due to Dengvaxia have spawned a vaccination scare that led to a drop in immunization coverage in the country to 40 percent last year, from an average 70 percent in recent years.