Measles Epidemiology Shows Striking Contrast
Congo Outbreak
Kills 4,000 Children - None in 2019 US Outbreak
“Measles has caused so much damage in my village…there
were deaths in almost every house. Some families have lost two, three,
or even four children.”
That’s how one resident of Kasai Province in the
Democratic Republic of the Congo (DRC) has described the impact of the
ongoing measles outbreak in the Congo, according to Doctors Without
Borders.
Measles virus in 2019 has provided a striking
revelation of the difference between the current epidemiology of the
disease in the US and a developing African country with different
health systems and vaccination programs.
Congo Outbreak
The outbreak declared in June in the DRC has evolved to
become the world’s largest and fastest moving outbreak, according to
the WHO regional office in Africa. To date the number of suspected
cases has gone beyond 203,000 with more than 4,000 deaths, almost all
of them children.
The Congolese government and WHO have launched measles
vaccination campaigns which are expected to reach over 800,000
children aged 9-59 months. A goal is to protect the children who were
not vaccinated through the routine immunization program and therefore
achieve the needed high levels of population immunity.
The exacting toll in the Congo stems both from failure
to vaccinate and from inability to adequately treat children affected
by the disease.
Barriers
Doctors Without Borders reports that several factors
are responsible for the surge in cases in 2019. These factors include
1) low immunization coverage, 2) irregular supply or even stock-outs
of vaccines, 3) a weakened surveillance system, 4) limited logistical
means that undermine the cold chain needed for vaccines, 5) armed
conflicts and displacement that paralyze the health system in some
areas, and 6) financial or geographic barriers limiting or even
preventing patients’ access to health facilities.
Ebola Contrast
The measles situation is in striking contrast to the
situation with Ebola also raging in DRC in 2018-19. It is the second
largest outbreak of the disease on record, and despite having a much
higher mortality rate, the Ebola virus has caused only about half of
the deaths associated with measles (~2,000).
Better Approaches
What is needed to battle vaccine preventable disease
according to international aid organizations is more focus on giving
resources that can create or improve overall health care
infrastructure which in turn can provide decentralized capacity to
provide care to all communities.
US Outbreak
The United States registered 1,249 measles cases in 22
separate outbreaks in 2019 which is the most cases reported in a
single year since 1992, according to the Centers for Disease Control.
The virus has been considered eliminated from the US since 2000
because the virus is no longer endemic.
Source
The outbreaks in 2019 stemmed mostly from travelers who
acquired measles outside the United States and subsequently
transmitted the infection to unvaccinated persons back in the US. The
unusually large number of cases for the US were widespread in 17
states and generated considerable publicity throughout the year mostly
centered on pockets of unvaccinated persons who refuse or neglect to
have their children vaccinated for religious or philosophical reasons.
In 2019, close-knit Orthodox Jewish communities in New York accounted
for 75% of all the cases. State public health officials moved to
strengthen the laws governing any exemptions from school vaccination
requirements.
Ten percent or 119 measles cases were hospitalized in
the US and no deaths were reported to CDC.
Characteristics
The majority of outbreaks in the US were small and of
limited duration because of high population level immunity and rapid
outbreak control responses.
The New York oubreaks were larger and lasted longer
because of the size of the pockets of susceptibles in the affected
religious communities. Nevertheless, outbreak control measures were
sufficient to halt the outbreaks before they had lasted 12 months and
allowed the US to retain its status as a country where measles has
been eliminated because the cases did not persist longer than one
year. ■
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