Page 107 - JSOM Summer 2019

An Ongoing Series

Measles Vaccination

A Matter of Confidence and Commitment

Richard Turner, on Behalf of the PLoS Medicine Editors*

rominent among the anxieties of our times are those Vaccine Action Plan 2015–2020 recognizes the need for high
regarding health and disease. Not only are ageing pop- and consistent levels of vaccine coverage yet acknowledges the
Pulations expected to suffer an increased burden of non- difficulties in meeting the challenges of achieving high and eq-
communicable diseases in the future, but risks of and harms uitable coverage, owing to the existing pronounced variations
from existing and emerging infectious diseases could also in national and regional coverage with measles vaccination.
increase, owing to population growth, migration, climate
change, and other factors. At the population level, it is clear In the United States, despite the declared elimination of mea-
that the hard-won gains in medicine and public health brought sles in 2000, outbreaks have been well documented in recent
about by vaccination, antimicrobial and other treatments, and years—the outbreak in Southern California during December
improved sanitation will need to be sustained, broadened, and 2014–February 2015 involved at least 125 cases. Among
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intensified to protect and provide for an increasing proportion these cases, a substantial proportion were in people known
of the human population. Global aspirations, including those not to have been vaccinated, including infants who were too
set out in the Sustainable Development Goals, are unambigu- young to have been protected and individuals who had chosen
ous in setting out an anticipated future trajectory of improved not to receive measles vaccination (i.e., 49 people were unvac-
health, well-being, and prosperity. cinated among the 110 cases identified in California). More
recently, an outbreak in Clark County, Washington State has
Measles, a highly contagious viral infection, is in various re- been widely reported in the past few weeks, and at the time
spects the perfect example of a threat to health that respects of writing there had been 65 confirmed measles cases in this
neither aspirations nor boundaries between developed and area. In 2018, writing in PLoS Medicine, Jacqueline Olive
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developing countries. Complications of measles infection in- and colleagues highlighted clusters of people claiming non-
clude pneumonia (the most common cause of death in chil- medical exemptions from measles vaccination in states where
dren with measles), encephalitis, ear infections that can lead to this is permitted by law. The authors noted that “new foci
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permanent deafness, and diarrhea. Although a safe and very of antivaccine activities are being established in major met-
effective two-dose vaccination schedule has been available and ropolitan areas, rendering select cities vulnerable for vaccina-
widely deployed since the 1960s, the need for very high and tion-preventable diseases.” It is difficult to imagine a future
consistent vaccination coverage to elicit herd immunity means scenario without repeated and serious measles outbreaks in
that the disease burden and harms of measles remain substan- the US and elsewhere, given the gaps in protection against the
tial. WHO reports that globally, in an apparent uptrend of disease. A cautionary indication of the extent to which the
cases occurring in 2017, measles led to an estimated 110,000 dangers of so-called “vaccine hesitancy” can escalate is in the
deaths, most in children aged under 5 years. Tragically, these Philippines, where there are reported to have been thousands
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deaths were unavoidable, given the estimated 20.8 million of measles cases and at least 189 deaths since the beginning of
children in low- and middle-income countries who had not 2019, mainly in children. 6
received a single dose of measles vaccine through routine pro-
grams in that year. The reasons for people not accepting vaccination against
measles and other potentially fatal and readily preventable in-
In the 53 high- and middle-income countries that make up fections are, unfortunately, all too well known. Fears about
its European region, WHO has indicated that around 82,500 potential harms of the combined measles, mumps, and rubella
cases of measles were reported in 2018, an alarmingly high vaccination were raised by a discredited study published in
number even among a population in excess of 900 million peo- The Lancet in 1998 and are continuing to circulate. As Peter
ple, and a greater than 3-fold increase since 2017. There were Hotez, dean of the National School of Tropical Medicine at
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72 reported deaths in children and adults. Here, the European Baylor College of Medicine, Houston, Texas, commented to
*Published: March 26, 2019; https://doi.org/10.1371/journal.pmed.1002770
Copyright: © 2019 Turner, on behalf of the PLoS Medicine Editors. This is an open access article distributed under the terms of the Creative
Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and
source are credited.

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