Lawmakers in the Philippines are scrutinizing official decisions to pursue the wide-scale introduction of the world's first dengue vaccine despite objections from government experts, and continue its use after a subsequent warning from the World Health Organization.
Former President Benigno Aquino III's administration launched the vaccination drive in April 2016 with the goal of immunizing one million children against dengue, which is caused by a mosquito-borne virus. The potentially fatal disease can cause fever, headaches, joint pain and possibly internal bleeding.
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In a congressional hearing on Thursday, Mr. Aquino told lawmakers that he had seen the disease as a significant enough problem in his country that he met with executives from French pharmaceutical maker Sanofi SA two times before his government approved its vaccine, Dengvaxia.
The government drive proceeded against the wishes of an advisory panel of doctors at the Department of Health, which raised concern over the lack of long-term safety data for the vaccine.
In the 20 months that followed the launch of the drive, the Philippines vaccinated over 800,000 children.
President Rodrigo Duterte's administration picked up the program after he took office at the end of June 2016.
The WHO said the following month that the vaccine could expose people previously uninfected with dengue to an elevated risk of severe dengue, the potentially lethal form of the virus.
The government found in late 2016 that there were unspecified "adverse events following immunization" in the five months leading up to Aug. 20, 2016, for at least 997 children out of more than 400,000 who had received a dose in that period, according to a document prepared for the congressional investigation and reviewed by The Wall Street Journal.
The document said that at least 30 of those children were hospitalized because of "serious illnesses" and at least two died. The two deaths weren't attributed to dengue. It hasn't been established that the Dengvaxia inoculation resulted in any cases of severe dengue or deaths in the Philippines.
Sanofi said last month that after additional analysis it had determined that the vaccine isn't suitable for people who hadn't been infected previously with dengue. For those people, "more cases of severe disease could occur" if they receive the vaccine and later contract the virus, the company said.
Lawmakers last week began questioning former and current officials, doctors, public-health experts and Sanofi executives in an effort to determine, among other things, why Manila didn't suspend the program until this month.
Sanofi said the vaccine is still effective for people who have previously contracted dengue. Dengvaxia, a live-virus vaccine, is administered in three doses, taken six months apart, and gains in effectiveness with each successive dose, the company said; effectiveness also varies against each of the four strains of dengue, according to Sanofi.
The Philippines didn't test for previous dengue infection as part of the vaccination program, according to the document prepared for the congressional investigation.
Mr. Aquino told lawmakers on Thursday that he acted in good faith when deciding to use the vaccine in a mass drive, and that no concerns had been raised directly with him.
Mr. Duterte said he welcomed the investigation by Congress. "If there is a failure, let them sort it out," he said Wednesday.
The Philippines was the first country to launch a mass immunization drive using Dengvaxia. The vaccine has been introduced in 10 other countries, but the only other one to use it for mass immunization is Brazil, where the program has been confined to Paraná, a state hit hard by dengue epidemics in recent years.
No serious side effects have been reported there, said a spokeswoman for the state, who said prior exposure to dengue was prevalent in the region.
The dengue virus infects 390 million people globally every year and kills tens of thousands, according to the WHO. More than 200,000 people contracted dengue in the Philippines last year.
For 10-year-old Christine Mae de Guzman, her symptoms began with a throbbing headache one day in October 2016, according to her parents. Within days she had died, succumbing to severe dengue, according to a medical record reviewed by the Journal.
Her mother, Marivic de Guzman, said she couldn't understand why her daughter got the disease because Christine had received a dose of Dengvaxia earlier that year and had no prior history of the virus. Christine died shortly before she was due to get her second dose.
Christine's school in the province of Bataan, about 80 miles northwest of Manila, had been among the first to take part in the immunization drive.
"Of course we approved of it," said Christine's father, Nelson de Guzman. "It was for her health."
Sanofi said it wasn't in a position to comment on Christine's case because it hadn't been reported to the company. The company said its studies showed it takes three years for any increased risk to surface after the first shot. Christine died six months after receiving hers.
The Department of Health said it plans to sue Sanofi and demand a refund for the roughly $70 million it says it spent to buy the vaccine. It said it wants Sanofi to cover medical costs associated with any future hospitalizations.
A Sanofi spokesman said the drugmaker hasn't received legal notice from the government.
--Aricel Saludo-Garcia in Manila and Paulo Trevisani in Brasília contributed to this article.
Write to Preetika Rana at email@example.com
(END) Dow Jones Newswires
December 17, 2017 23:12 ET (04:12 GMT)