‘Lift Dengvaxia ban, but no mass vaccination’

MANILA, Philippines — An infectious disease expert from the University of the Philippines-Manila recommended yesterday the lifting of the ban on the use of Dengvaxia vaccine in private clinics, saying there is a testing tool available in the country to detect previous dengue infections.

Edsel Maurice Salvana, director of the Institute of Molecular Biology and Biotechnology at UP-Manila’s National Institutes of Health, told The STAR yesterday that a blanket ban on Dengvaxia should not be imposed because there is still a way to identify past dengue infections.

“It is called indirect IgG Dengue Elisa, which is available in the Philippines in commercial laboratories. It was even mentioned by the World Health Organization,” said Salvana, referring to the April 2018 updated recommendation of WHO-Strategic Advisory Group of Experts on Immunization on the use of Dengvaxia.

Salvana said the IgG Dengue Elisa can be used as a pre-screening tool to determine if a person has had dengue in the past.

However, he noted that since it takes one to two days before the results of this testing tool can come out, Dengavaxia cannot be administered during a mass vaccination.

Instead, the vaccine can be used for voluntary immunization in private clinics.

He added for mass mass vaccination, a “point-of-care” test is needed, which is like a pregnancy test that an obstetric gynecologist uses wherein results are immediately available.

Salvana made the statement following pronouncements of National Dengvaxia Task Force and Department of Health regional director Eduardo Janairo of Calabarzon that they will not recommend to the DOH the restoration of certificate of product registration of Dengvaxia.

Janairo said the vaccine is not effective in preventing dengue infection as they recorded 26 vaccinees who acquired dengue in Calabarzon. Seven of them have received the complete three doses of the vaccine.

Around 172,000 public elementary school children were given Dengvaxia in Calabarzon.

DOH data showed the number of dengue cases in the country had already reached 188,562 from Jan. 1 to Aug. 13, including 807 deaths.

Officials said this is the highest number of dengue cases in the last five years. This is also more than 90 percent higher than the cases during the same period in 2018.

The rapid spread of the virus prompted the DOH to declare a national dengue epidemic, he added.

Salvana said that while Dengvaxia cannot address the current dengue epidemic, it will be beneficial in preventing severe dengue.

He maintained that with the efficacy rate of 93 percent, the number of deaths from dengue this year would have been reduced by half if the victims eligible to receive Dengvaxia were vaccinated.

“Assuming that all those current 807 deaths right now are from severe dengue and at least half of them were above 10 years old – meaning they were eligible to receive the vaccine at an efficacy rate of 93 percent reduction of severe dengue, we are looking at at least 400 lives saved just for this epidemic,” he added.

Testing tool

“IgG Dengue Elisa is one option to enable medical practitioners to determine if a person had a previous dengue infection, and this test is available in many dengue endemic countries,” he said

Salvana added that the other drawback in using IgG Dengue Elisa is its “possible cross-reactivity with other flaviviruses such as Zika virus or Japanese encephalitis virus may occur, giving rise to false positive results.”

The certificate of product registration of Dengvaxia was permanently cancelled by the Food and Drug Administration after its manufacturer French firm Sanofi Pasteur, had failed to submit post-marketing surveillance.

The company had filed an appeal with the DOH which has been reviewing it.

Health Secretary Francisco Duque III said in an interview that they will release the results of the review this week.

“It will be a good time to already talk more about it lengthily and I would also need to have the legal service of DOH to join me (in releasing results) because there would be some legal principles involved,” he added.

Also reacting to Janairo’s announcement, Philippine Foundation for Vaccination executive director Lulu Bravo said no vaccine is 100 percent perfect.

In an interview, she claimed that “Dengvaxia, based on clinical trial will reduce severity by 93 percent and hospitalization by 80 percent.”

“It’s the same as in other vaccines. Measles vaccines will not give 100 percent (efficacy) just like hepatitis B, chicken pox, etc. But we keep on vaccinating, right? There’s many literature saying mosquito repellants are inffective and yet they recommend it (to fight dengue),” Bravo added.

The Negros Occidental Provincial Health Office reported that 37 dengue patients have died in the province from January to Aug. 10 with 5,900 cases recorded, which is a 60 percent increase compared to the same period last year.

The Sangguniang Panlungsod of Bacolod City also approved an appropriation ordinance for P17.8 million on the request of the City Health Office for its campaign against dengue.

Dr. Grace Tan, Environmental Sanitation Division head of the City Health Office, said the fund will be used for medicines, chemicals and equipment for their dengue campaign.

Tan said they have reached the alert level since the DOH declared a Dengue National Outbreak. – With Gilbert Bayoran, Gerry Lee Gorit, Ben Serrano