EDITORIAL - Settle the Dengvaxia controversy

If uptake of COVID-19 vaccines and boosters continues to be tepid during this week’s three-day mass vaccination program, part of the reason has to be the lingering impact of the hysteria over the Dengvaxia controversy. Litigation over deaths allegedly caused by Dengvaxia must be speeded up if the government wants to significantly reduce hesitancy not just for the anti-dengue shot but also for other vaccines against several preventable but potentially deadly diseases.

Developed by French pharmaceutical giant Sanofi Pasteur, Dengvaxia is the first dengue vaccine to be approved by global health authorities. In June 2016, the World Health Organization and its Strategic Advisory Group of Experts on Immunization or SAGE endorsed the vaccine for use among ages nine to 45 in countries where dengue is endemic.

By the end of 2016, the Philippines, Brazil and nine other countries had granted regulatory approval for Dengvaxia. Following the WHO and SAGE endorsements, the Philippines rolled out the vaccination program, targeting one million nine-year-olds in three regions with the highest cases of dengue.

As Sanofi Pasteur continued its research and testing, however, additional data indicated that the vaccine increased the risk of severe dengue for those who have never had the disease. When the company issued this warning in November 2017, the Philippines had already given the vaccine to 800,000 school children. The consequent hysteria attributed 99 children’s deaths to the vaccine and led to indictments for homicide and “torture of children” against about 40 government officials at the time.

Following deliberations by SAGE, the WHO updated its guidelines on the use of Dengvaxia in 2017, but did not recommend the discontinuation of the use of the vaccine in dengue-endemic areas. In 2019, the WHO added the vaccine to its model list of essential medicines. Dengvaxia remains approved for use in countries including Brazil, Indonesia, Mexico, Singapore and Thailand. It has also been approved in non-dengue endemic countries such as the United States and those covered by the European Medicines Agency.

Still, the Philippines banned Dengvaxia in 2019. The scare also affected the country’s general vaccination program, with vaccine uptake for measles falling from 88 percent in 2014 to just 55 percent in 2018. Measles outbreaks inevitably erupted, with cases surging from 2,400 confirmed infections in 2017 to 18,000 in 2018 and a massive 48,871 the following year. In September 2019, polio also made a comeback in the Philippines, 19 years after the country was declared polio-free.

A scientifically sound resolution of the Dengvaxia controversy may help ease vaccine hesitancy, which is being seen even in the COVID inoculation drive. Litigation of the Dengvaxia case should not crawl along as usual.