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letter from the editor | 270

Public health challenges

An article recently published in The New York Times (“Anti-Vaccine Activists Have Taken Vaccine Science Hostage,” August 5) warns that fear of being misinterpreted has caused vaccine researchers to avoid talking about potential negative aspects of their effectiveness and safety, even minimizing results that could indicate problems related to their use. Considering the recent rise in epidemics of preventable diseases, this fear is not unfounded. The article argues that self-censorship, however, can place scientists on the same footing as anti-vaccination activists, with both selecting data that reinforces their own perspective. Transparency in science, the article concludes, is essential to encouraging people to get vaccinated, since even the slightest secrecy increases public distrust in one of the world’s most important public health achievements.

This issue’s cover story (page 18) attempts to unravel recent Brazilian media reports that vaccine uptake in the country, which was previously considered excellent, has dropped significantly in the last two years (by as much as 21 percentage points). The proportion of children vaccinated against poliomyelitis, rotavirus, hepatitis A and B, and meningitis in 2017 was the lowest in years, and was well below the rate recommended by the World Health Organization, making the country more susceptible to epidemics.

This alarming data has naturally led to one key question: why? Several causes have been proposed, but as yet there is no evidence of how much each factor actually contributes to the current situation. Of the five reasons highlighted by the Brazilian Ministry of Health, four relate to a lack of knowledge or communication. They are: a misleading perception that diseases such as polio have disappeared, making immunization unnecessary; ignorance of the complex mandatory vaccination schedule; an (unfounded) fear that receiving lots of vaccines overwhelms the immune system; and more worrying still, a fear that immunization may cause harmful side effects.

The fifth reason, more practical in nature, relates to the operating hours of public health clinics, which usually only open on weekdays during business hours. Another explanation offered by experts is that the number of vaccines registered fell due to a change in the immunization records system. Scientists and health officials are urgently trying to get to the bottom of what has caused this abrupt decline, and are taking steps to reverse the situation before serious issues—such as the recent measles outbreak in Manaus—spread throughout the country.

Brazil received the maximum score for its treatment of three vaccine-preventable diseases (measles, tetanus, and diphtheria) in a comparative analysis of national health system access and quality in 195 countries (page 25). In a ranking based on data from 1990 to 2016, Brazil placed 96th and overall has improved since the previous survey, although the disparities between health services in different states has increased. Public health systems worldwide have improved in general, but the contrasts between more and less developed nations have become more pronounced.

Still on the topic of health, in 2014 a small group of scientific journals, including the British Medical Journal, began inviting patients with certain diseases and their caregivers to evaluate scientific papers in parallel to traditional peer review (page 38). According to the journal, they are able to provide ideas and perspectives often overlooked by the academic review system.