Editor’s note: Edsel Maurice T. Salvana, MD, DTM&H, FPCP, FIDSA is an internationally-acclaimed infectious diseases physician, health advocate, and TED fellow. He is the director of the Institute of Molecular Biology and Biotechnology at the University of the Philippines National Institutes of Health. He is also an adjunct faculty for global health at the University of Pittsburgh. The opinions expressed on this piece are the author's.
Manila (CNN Philippines Life) — In the 1950s, one out of five children died before the age of five. Many of these children succumbed to vaccine-preventable diseases, particularly measles. The introduction of an effective measles vaccine in 1963 saw a steep decline in childhood deaths. The World Health Organization estimates that the measles vaccine prevented over 21 million deaths globally from 2000 to 2017.
Yet, despite its life-saving and world-changing impact, the measles vaccine and the breakthrough science behind it are under attack. Anti-vaccine “advocates,” or “anti-vaxxers,” are undermining decades of progress in eliminating some of the deadliest and most debilitating diseases. In resource-limited countries, the combination of measles and malnutrition can kill one-third of children who are not given the vaccine. Measles is transmitted very efficiently through the air, and outbreaks in areas with poor vaccination rates progress rapidly and threaten nearby communities.
Vaccines are among the most effective public health interventions invented by man. It is right up there with sanitation and clean water. However, it is easily taken for granted as people forget what the diseases being prevented look like. Vaccines have become a victim of their own success. Like any medication, vaccines have side effects and it is hard to understand why a person would expose a child to a potentially (tiny risk, but nevertheless possible) harmful intervention when the target disease has not been seen for years. Parents in the 1950s were deathly scared of polio, which could doom their children to life inside an iron lung since polio could paralyze the muscles used for breathing.
Polio vaccination in the early years was wildly successful as a result of this fear. As more children received the vaccine, fewer cases emerged. Side effects from the live polio vaccine eventually outpaced the actual cases of polio, understandably forcing doctors to switch to a killed vaccine with less potential for harm. But it is difficult to appreciate how well a vaccine works when you cannot see the benefit, and this set the stage for the rise of the anti-vaxxers.
“Vaccines are among the most effective public health interventions invented by man.”
In 1998, a physician named Andrew Wakefield published a study in a prestigious medical journal that suggested that the combination measles, mumps and rubella vaccine was linked to autism. Anti-vaxxers rejoiced and actively attacked vaccination. Later it was shown that Dr. Wakefield had pretty much made the study up, and that he was guilty of unethical practices. But the damage had been done, and vaccine confidence had been shaken. Despite study after study debunking the link between vaccines and autism, the anti-vaccine movement gained traction and vaccination rates plummeted across the world.
This decrease in vaccine confidence did not spare the Philippines. Since 1998, basic vaccination rates in children have languished below 80 percent, with a coverage of only 70 percent at the end of 2017. With the Dengvaxia controversy erupting in the news, vaccine uptake further plummeted to historic lows, with some areas reporting only 40 percent coverage. Measles cases quadrupled in 2018 compared to the year before. We are currently in the midst of a ten-fold rise in measles cases in the National Capital Region, with multiple deaths and reports of further outbreaks elsewhere.
Did the Dengvaxia controversy cause the current epidemic? Not entirely. But it certainly didn’t help. Vaccine confidence was already shaky as a result of the Wakefield study, and the hysteria surrounding the dengue vaccination program may have been the last straw. Many health centers were reporting that the most common reason for declining vaccines in the last year was because of Dengvaxia, and continued attacks on the Department of Health on media further undermine confidence in the government.
As more people die, how do we move forward? Restoring confidence in DOH and in vaccines needs to be the priority, so that people will start vaccinating their children again.
“We need to move on from this situation where we have demonized a vaccine that was improperly used, and stick to the facts. Hold those who improperly used it accountable, but do not make false accusations without scientific basis that further undermines vaccine confidence.”
While there was probably some wrongdoing in prematurely implementing a mass immunization program with a new vaccine, a lot of misinformation has muddled the facts. Dengvaxia as a vaccine for dengue in those with previous infection works. It decreases severe dengue risk by over 90 percent.
For those without previous dengue infection, it prematurely increases severe dengue risk to the level of an unvaccinated seropositive (with blood evidence of previous dengue infection), or from 0.2 percent to 0.5 percent. Nearly 90 percent of Filipino children above the age of 9 years old are seropositive even if they never looked sick, since only one out of five people with a previous dengue infection manifest any symptoms. No deaths have been linked directly to the vaccine, despite uncorroborated pronouncements based on gross autopsy findings from the Public Attorney’s Office. The dengue vaccine has now been approved for use by 20 countries, and the Philippines is the only country that has suspended it.
We need to move on from this situation where we have demonized a vaccine that was improperly used, and stick to the facts. Hold those who improperly used it accountable, but do not make false accusations without scientific basis that further undermines vaccine confidence. And most of all, help the prematurely vaccinated children who may be at higher risk for severe dengue through vigilant surveillance, but don’t attribute every single malady to the vaccine without reason.
If there ever was a magic bullet in medicine, vaccines would be it. Unfortunately, many have forgotten just how bad things were before vaccines came along. This collective amnesia will be the death of many, many children. Hopefully these outbreaks will serve as a wake-up call to those of us who have become complacent, or are in denial. It is truly unfortunate that it comes at the cost of innocent lives.