Dengvaxia: the facts (2)

Last week I asked why there was such a rush to undertake the inoculation program. Well, at the time dengue cases had risen alarmingly, and some urgent action was required. But it was a most unusually quick action for a usually slow-acting administration, and why it happened should be delved into more. The reason could be as legitimate as the acceleration of the disease at the time, requiring quick action. But even if that’s what it was, the question on the speed and manner has to be answered. Or it could be an administration wanting to look good for an upcoming election it wanted to win.

But vaccination against dengue should continue; it can greatly reduce the number who would otherwise suffer from the infection, as well as the number of deaths—900 in 2016—about which I don’t see headlines. The World Health Organization has updated its guidelines and acknowledged that the dengue vaccine can have significant population-level benefits in highly endemic areas. It recommended continued vaccination of individuals who have started vaccination.

Note further that where the prevalence of dengue is 85 percent, as here, for every case of severe dengue in a seronegative person, 10 seropositive persons are saved from illness.

As the WHO says, “If the vaccine is administered in a population with a high seroprevalence, there is still a significant benefit in terms of reduction of severe dengue and hospitalizations due to dengue… WHO recommends vaccination only in individuals with a documented past dengue infection, either by a diagnostic test or by a documented medical history of past dengue illness.” The preferred approach would have been to apply a rapid diagnostic test at the time of vaccination, but such an assay is still being developed. The Department of Health, however, should have done a better check of past history. It didn’t.

What all this says is that the chance of a child who had been inoculated suffering a severe case of dengue is small, and of death even smaller. Both are more likely if they are not vaccinated.

It’s not financially possible to vaccinate the whole population, and there are some areas (where dengue prevalence is less than 70 percent) where it wouldn’t be advisable. But to inoculate kids as they turn nine would eventually lead to significant impact on decreasing the dengue transmission. But best to wait until a test kit is available to check if children are seropositive or seronegative, and not inoculate them until they have been infected—if they do get subsequently infected.

Esquire magazine published an article by Dr. Edsel Salvaña whose title says it all: “How the Dengvaxia scandal might destroy a good vaccine.”

Dr. Salvaña wrote that “from a public health perspective, the decision to use the vaccine is a much easier one. In highly endemic settings such as the Philippines, where nearly 95 percent of children above 11 years old have evidence of past dengue infection, the risk-to-benefit ratio is clear.”

We need to separate the politics from the medicine. Let Congress focus on whether the decision and the order to use it were done in the right way. Let’s leave the DOH and the Food and Drug Administration to do their job, assisted, I’d suggest, by the WHO and unhampered by political interference. Particularly in the forensic analysis of the children who recently died: Was it dengue? If it was, did they have the three inoculations necessary? Were they seropositive or seronegative? (This may not be determined solely through a discussion with parents. That’s not very reliable.)

What disturbs me most about this whole sorry issue is the rush to judgment without looking first into the facts. I am sure Senators Dick Gordon and JV Ejercito will ferret that out. As to its priority over other equally urgent issues, that’s a judgment call I’ll leave to those more expert in arguing. What is very sad about all this is that people are now scared to be inoculated—for anything. What has been lost is the fact that no drug is perfect, no drug works 100 percent. If vaccination helps more than hurts people, it should be done. Dengvaxia reduces the chance of suffering a severe case of dengue by 93 percent. It is beneficial to far more than the very few it might hurt. I suggest that we follow the DOH’s call to work together in finding a solution to resolve this issue dispassionately, without further scaring a scared public.

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Read my previous columns: www.wallacebusinessforum.com E-mail: wallace_likeitis@wbf.ph

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