DTP-Vaccinated African Infants Had a Higher Death Rate than Unvaccinated Infants, According to New “vax/unvax” Study
A study published earlier this month (see HERE ) examining the effect of vaccination on mortality in 3-5 month old infants in the West African nation of Guinea-Bissau showed a fivefold higher death rates in infants who received diphtheria-tetanus-pertussis (DTP) and oral polio (OPV) vaccines compared to unvaccinated infants. The study, published in the journal EBioMedicine by Danish researchers from the Statens Serum Institut (SSI), was based on infants born between 1980 and 1983 and used data collected by the SSI’s Bandim Health Project (BHP). The study of vaccinated and unvaccinated African infants represents a rare, albeit limited, example of the kind of “vaxxed/unvaxxed’ study that many critics of American vaccination policy have long called for.
In their prospective study of over 1,000 infants, the SSI authors examined the effects on infant mortality of a new vaccination program that included both OPV and DTP vaccines. They reserved their harshest assessment for the newly introduced DTP vaccine, observing pointedly that “DTP was associated with 5-fold higher mortality than being unvaccinated. No prospective study has shown beneficial survival effects of DTP.”
In a broader criticism of global vaccine policy, the authors continued, “Unfortunately, DTP is the most widely used vaccine, and the proportion who receives DTP3 [three doses of the DTP vaccine] is used globally as an indicator of the performance of national vaccination programs.” In a further criticism of DTP vaccines, the analysis suggests that the OPV, which was typically administered together with DTP vaccine, had a moderating effect on the death risk of DTP. When (due to logistical problems with OPV availability) infants were vaccinated with DTP only, the death rates were even worse: as much as ten times higher than unvaccinated infants.
Unlike the recently leaked “vax/unvaxxed” study on homeschool children (see HERE) and the more commonly understood usage today of the “vaxxed/unvaxxed” concept, this analysis was narrower. The study examined infants during a brief window of time—the period between 3 and 6 months of age--and measured a single outcome—death. Described by the authors as a “natural experiment,” the study was designed in order to address on ongoing debate over the efficacy in low-income countries of the Expanded Immunization Program (EPI) since its introduction in the 1970s. At the time, the EPI targeted countries like Guinea-Bissau that had high infant mortality rates--under-five mortality rates were close to 50% there in 1978-9—and included four vaccines for seven diseases. Since individual vaccines included in the EPI might have different effects, the authors decried the absence of “individually randomized studies,” noting that “surprisingly few studies examined the introduction of vaccines and their impact on child survival.”
Due to its specific focus, the study design has little to say about the vaccine schedule debate in high-income countries and has several key limitations. Most notably, the “unvaccinated” children in the BHP study group only remained unvaccinated for a period of less than 14 weeks between 3 and 6 months of age until they attended the “quarterly weighing sessions” when OPV and DTP vaccines were administered. Even this briefly unvaccinated group wasn’t fully unvaccinated. The authors noted that “of the 651 unvaccinated children, 219 received DTP and/or OPV before their first weighing examination. These children counted as ‘unvaccinated’ until their first weighing examination.” Even though the death rate in the unvaccinated group was lower than in the vaccinated group, death rates were high on both sides. Five of the eighteen deaths covered in the study period occurred in the unvaccinated group and the authors don’t disclose whether any of these deaths had received a vaccination before the official examination “landmarks” used to define vaccination events in the database.