On
March 23, 2013 the World Health Organization announced an outbreak of Ebola
Virus Disease in the country of Guinea.[1] Located in West Africa,
the tiny country is home to nearly 11 million people and is ranked 179th
on the Human Development Index.[2] The fact that it was the World
Health Organization, and not the Guinea Ministry of Health, that made the
announcement of the outbreak is telling in and of itself. Guinea had not
detected the outbreak, it was only the coincidental presence of a Médecins Sans Frontieres team in the
country to treat a Malaria outbreak that led to the discovery of what would
become the largest Ebola outbreak in the history of the disease.[3] This
paper will analyze the health surveillance system of Guinea in an effort to
understand how such an outbreak could have gone unnoticed, continuing to spread
among the population and to neighboring countries for nearly three months
before the WHO announcement.
The Guinea Ministry of Health and
Public Hygiene did have a simple national health surveillance system in place
prior to the outbreak. Each Prefectural Health Directorate reported their
weekly tallies to the Directorate of Prevention and Disease Control which
compiled that data into a national database of cases.[4] But that
system was limited by both resource constraints and the number of physicians
and healthcare workers in the country. There is one physician for every 7,143
people in the country, compared to one physician for every 500 people in the
United States.[1] Physicians in Guinea have significantly less
capability to follow up on idiopathic cases with a pathological investigation.
And those that did would have had limited lab capabilities, mainly focused
around the infectious diseases considered endemic to the region.
The fatal flaw in the system lay in
its inflexible nature. The system had been designed nearly entirely around
monitoring patients with symptoms of the major infectious diseases: Yellow
Fever, Cholera, Poliomyelitis, and to a much smaller extent certain Viral
Hemorrhagic Fevers such as Marburg and Crimean-Congo, but never Ebola.[4]
And there was simply no capacity for the system to identify new infectious
disease outbreaks that hadn’t been previously identified in the region.
The data that was available in
Guinea rarely went beyond simple case counts.
And where electronic records were kept, they were often incomplete or
invalid.[4] Few organizations were active in the area, meaning that
the Ministry of Health numbers were generally taken at face value, with no
effort expended in order to determine the actual numbers of infected persons by
other means.
As previously stated, the number of
physicians meant that workload was high and resources scarce. Furthermore,
almost 93% of all health expenditures occurred outside the formal health
infrastructure, meaning physicians were unlikely to see even a tenth of the
population with health complaints. Previous
efforts at reforming the Guinea Health System, such as the Bamako Initiative of
1987, were primarily focused around access to drugs and essential health
services. Little or no consideration was
given to infectious disease surveillance.[6]
The sensitivity of the system to
detecting the endemic diseases is impossible to verify. Retrospective case finding by the WHO
indicates that by time the first Ebola case had been confirmed by the Insitiut
Pasteur in Paris, there were at least 59 cases throughout Guinea, and likely
more in the neighboring countries of Sierra Leone and Liberia.[3]
Because no cases were reported, there was no Predictive Value Positive for the
surveillance system. In fact, had staff from Médecins Sans
Frontieres not brought the disease to the attention of the Ministry of Health
and Public Hygiene, it is unlikely that it would have been detected at all.
Rather, it would most likely have been brought to light when the disease spread
to a country with a more developed surveillance system.
The failure of the system to detect
the Ebola Virus Disease outbreak in a timely fashion makes it difficult to put
much faith in the system’s ability to provide an accurate picture of the
overall state of health in the country of Guinea. With the tide of the Ebola
outbreak now receding, it is likely that the accompanying loss in funding and
resources will draw with it the ability of the country to detect, identify, and
treat disease. With the devastating
effect the disease has had on healthcare workers, the surveillance system will
likely operate at an even lower level than before. Without the benefit of
additional capacity in diagnostic facilities and healthcare workers, the system
will continue to rely on the presence of outside organizations for major
components of healthcare such as infectious disease surveillance, making it
impossible for it to respond to outbreaks in a timely manner.
The
failure of the Guinea infectious disease surveillance system is a story of the
disparity in global burden of disease.
Ebola cannot thrive in a country with a sensitive and timely
surveillance system, but such a system is reliant on effective institutions and
adequate resources that were not present in Guinea prior to the outbreak.
Furthermore, a surveillance system cannot detect what it isn’t looking for, and
this outbreak has demonstrated the great risk posed to numerous countries for
whom that same lack of effective institutions and adequate resources is the
norm. If these factors are not addressed
there is no way of preventing a new outbreak of viral hemorrhagic fever, an
aggressive strain of multi-drug resistant tuberculosis, or some other disease
that is just as costly as the one we are just now starting to bring under
control.
- World Health Organization. Ebola Virus Disease in Guinea. http://www.afro.who.int/en/clusters-a-programmes/dpc/epidemic-a-pandemic-alert-and-response/outbreak-news/4063-ebola-virus-disease-in-guinea.html. 23 March 2013\
- Central Intelligence Agency. (2014). Guinea. In The World Factbook. Retrieved from https://www.cia.gov/library/publications/the-world-factbook/geos/gv.html 14 February 2014.
- World Health Organization. Ground zero in Guinea: the outbreak smoulders – undetected – for more than 3 months. http://www.who.int/csr/disease/ebola/ebola-6-months/guinea/en/#. July 2013.
- Rebaudet S, Mengel MA, Koivogui L, et al. Deciphering the Origin of the 2012 Cholera Epidemic in Guinea by Integrating Epidemiological and Molecular Analyses. Ryan ET, ed. PLoS Neglected Tropical Diseases 2014;8(6):e2898. doi:10.1371/journal.pntd.0002898.
- Sudre B, Bompangue D (2009) Epidémiologie du choléra et Evaluation du Système d'Alerte Précoce en République de Guinée. Rapport de mission. UNICEF. in French. Available:https://wca.humanitarianresponse.info/fr/system/files/documents/files/EpidemiologieCholera_Evaluation_Guinee_dec09.pdf Accessed 13 December 2013.
- Ridde V. Report from West Africa: Is the Bamako Initiative Still Relevant for West African Health Systems? Int J Health Serv January 2011 41: 175-184, doi:10.2190/HS.41.1.l
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