Dengue Vaccine Controversy In The Philippines

A dengue vaccine put thousands of kids at risk for a deadly disorder. Some scientists says the manufacturer did too little to warn parents in the Philippines.

RACHEL MARTIN, HOST:

The U.S. FDA approved one of the most sought-after vaccines in recent decades on Wednesday. It's a vaccine to prevent dengue. Puerto Rico is particularly at risk for the disease. It's a mosquito-borne virus that infects more than a million people every day. It kills about 20,000 children every year.

The approval is currently only for kids, and it came with an important restriction. It can only be given to kids ages 9 to 16 who have had prior dengue infection. The vaccine was launched without that restriction in the Philippines and, as NPR's Michaeleen Doucleff reports, the repercussions there have been deadly.

MICHAELEEN DOUCLEFF, BYLINE: Back in 2016, the Philippines was all abuzz. The government was launching a massive vaccination campaign for nearly a million school kids. They held a big event, invited lots of media. Here's a recording from The Associated Press.

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JANETTE GARIN: (Foreign language spoken).

DOUCLEFF: A young girl, about age 9 or 10, was sitting on a stage in a bright yellow T-shirt with the words dengue is dangerous across it. The girl squeezed her eyes closed and bit her lip as the Health Secretary Dr. Janette Garin gave her a shot in her arm.

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GARIN: The drastic reduction in severity...

DOUCLEFF: Garin told the crowd that this shot, the world's first dengue vaccine, would save thousands of kids. The vaccine had been tested in a huge trial with more than 30,000 kids globally. The results were published in the prestigious New England Journal of Medicine. But halfway around the world, in a D.C. suburb, one scientist was worried.

SCOTT HALSTEAD: When I read the New England Journal article, I almost fell off the chair. To be honest with you, I was quite shocked.

DOUCLEFF: That's Dr. Scott Halstead. He spent more than 50 years studying dengue with the U.S. military. He says when he looked at the data, right away, he knew the vaccine had a problem - that it was putting some kids at risk for a potentially deadly side effect where your blood vessels start to leak, like with Ebola.

HALSTEAD: The trouble is that it occurs very rapidly - just a matter of hours. And this is what's so scary because, you know, there's nothing on the outside of the body that tells you, oh, that's a person that's leaking fluid inside.

DOUCLEFF: A child can go into shock.

HALSTEAD: Then everything gets worse, and you - maybe it's impossible to save your life.

DOUCLEFF: It's a complication called plasma leakage syndrome. Halstead says the risk is small, but still, he was so worried, he started writing editorials to scientific journals, even warned the Filipino government about the problem.

HALSTEAD: I just say, no, you can't give a vaccine to somebody - some perfectly normal, healthy person - and now put them at risk for the rest of their lives for plasma leakage syndrome. You can't do that.

DOUCLEFF: Sanofi Pasteur, the vaccine manufacturer, disagreed, and the Philippines campaign continued. Then, in November 2017, more than a year after kids started getting their shots, the vaccinations came to a screeching halt.

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UNIDENTIFIED REPORTER: Outrage and fear in the Philippines.

MARA CEPEDA: Suspends the sale of the controversial Dengvaxia dengue vaccine for a year.

BARNABY LO: Manufacturer Sanofi warned that the vaccine could trigger severe illness.

DOUCLEFF: Data confirmed Halstead's fears. The vaccine does raise the risk of hospitalization and plasma leakage syndrome for some kids. There were claims the vaccine killed 10 kids. Protests erupted across the country.

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UNIDENTIFIED PROTESTER: (Foreign language spoken).

DOUCLEFF: The Philippines Congress launched investigations.

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UNIDENTIFIED MEMBER OF CONGRESS: Good morning everyone. This hearing of the committee on accountability...

DOUCLEFF: Here's the problem. For children who have already been exposed to dengue, the vaccine is safe and works pretty well. But there is an unusual thing about the dengue virus. The second infection can be a lot worse than the first. So for kids who have never had the disease, the vaccine acts as the first exposure. So if they are exposed to dengue later on, they're at a higher chance of having this severe reaction.

The increased risk is small. Out of a million kids in the Philippines, the vaccine could cause about a thousand kids to be hospitalized. And Dr. Isabel Rodriguez at the University of California, San Francisco says parents were never told about this risk.

ISABEL RODRIGUEZ: What bothers me the most about this whole story is risk communication.

DOUCLEFF: Rodriguez, who studies dengue in South America, says Sanofi didn't acknowledge a potential risk until after 800,000 kids were vaccinated.

RODRIGUEZ: There was a lot of uncertainty. That, we knew from the beginning. But you need to communicate that explicitly. People need to be aware of that.

DOUCLEFF: Dr. Su-Peing Ng is global medical head of Sanofi Pasteur.

SU-PEING NG: We've always been very transparent in sharing the results of our research. And I just want to stress that we have full confidence in our vaccine as it's been approved by regulatory agencies in over 20 countries.

DOUCLEFF: In hindsight, given what's known now with the new data and everything, would you guys have done anything differently with this vaccine?

NG: No. We have been very, very close to the dengue research community, working closely with them over the last 20 years in the effort to find a solution for public health need.

DOUCLEFF: The Philippines government has indicted 14 government officials over the deaths of 10 children. The government said the officials acted with, quote, "undue haste in launching the campaign." Six Sanofi officials were also indicted for not properly helping children who had serious reactions to the shot. Sanofi disputes this, adding in a written statement to NPR, there is no clinical evidence that any reported fatalities were causally related to vaccination.

Dr. Keymanthri Moodley directs the Center for Medical Ethics and Law at Stellenbosch University. She says there is so much at stake in these situations. There can be deaths and other far-reaching consequences.

KEYMANTHRI MOODLEY: The problem that arises with a vaccine that goes wrong is that it creates fear and anxiety in terms of the public, especially the parents. And it can impact negatively on the established immunization programs that are actually safe and work very well.

DOUCLEFF: Which is what is happening in the Philippines. Many parents are now wary of getting their kids vaccinated for any disease. As a result...

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JAMELA ALINDOGAN: This is San Lazaro Hospital in Manila.

DOUCLEFF: ...The country is facing a massive measles outbreak. So far, there have been more than 26,000 cases.

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ALINDOGAN: At least 60 children have already died of measles in this hospital alone over the last month. And the situation is getting worse.

DOUCLEFF: That's Al Jazeera reporting in February shortly before the country launched an emergency measles vaccination campaign. Back in the U.S., the FDA yesterday approved Dengvaxia for use here with one important restriction. Doctors must have proof of a prior dengue infection to ensure the vaccine is safe for a child - a safeguard Filipino families never had.

Michaeleen Doucleff, NPR News.

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