About
a century ago, the first outbreak of epidemic meningitis in Nigeria occurred in Zungeru, a
town in Northern Nigeria near the River Niger. This outbreak was reported by
McGahey in 1905 in the Journal of Tropical Medicine and 32 cases were reviewed
in that report (Greenwood, 2006). There are no detailed accounts of the extent
of this epidemic, but it spread widely within that year and was recorded as reaching
Yola, a town in North-Eastern Nigeria, 500 miles east of Zungeru (as shown in the figure below). This first epidemic accounted for an estimated 20,000 cases and many
thousands of deaths.
It
is widely thought that the disease described by McGahey was meningitis because
of the wide age range affected and the characteristic signs and symptoms seen,
which were similar to cases of meningitis described elsewhere. Further
confirmation was obtained the next year (1906) when the disease spread to Ghana and the meningococcus was isolated by culture from cerebrospinal fluid (Greenwood,
2009). Even though it may not be certain if this meningitis epidemic was the
first ever in Northern Nigeria, recorded discussions with traditional rulers at
that time suggested that they recognized that this was a new illness (with strange
signs and symptoms). In addition, the writings of early medical explorers in
the 1700s and 1800s in Northern Nigeria (like Mungo Park, a surgeon), who had
written on diseases like malaria in the region, made no mention of epidemic
meningitis.
There
are many theories that try to explain how epidemic meningitis got to Northern
Nigeria (origin of the disease in the country). Greenwood (2009) outlines some
of them in his review, but it is not exactly certain which of them is the most
accurate. The first possible explanation is that a strain of the bacteria,
which is usually non-pathogenic and lives in the human airway epithelium
(commensals in the upper airway tract) acquired a virulent gene possibly by
mutation and became pathogenic causing disease and spreading in the population.
It is theorized that this same evolutionary process was responsible for the
first epidemic in Europe a century earlier.
Other
theories suggest that the disease was brought to Nigeria from Sudan; a large
epidemic was recorded in Omdurman, Sudan in 1989. There are suggestions that
the epidemic strain was brought into Northern Nigeria by West African pilgrims
who had embarked on the Hajj (Muslim
pilgrimage) and who travelled across Sudan before crossing the Red Sea to the
Arabian Peninsula and returned by the same route. These journeys from West
Africa across the Sudan could be completed, travelling by horse or camel, in a
few months, which is well within the period in which the causative bacteria can
persist in the upper airway tract. In modern times, the Hajj is still a place where international transmission of
meningitis still occurs even though in recent years mandatory vaccinations have
greatly reduced this risk.
In
Northern Nigeria, major meningitis epidemics were recorded in the medical
literature in 1949-1950, 1960-1962 and 1969-1970 (Blakebrough, et. al., 1982). The
report (see picture below) by Vollum and Griffiths (1962) describes their efforts to
control the epidemic of 1961 in the province of Katsina in Northern Nigeria.
They used sulphadimidine snuffs, which was very effective at that time. They
achieved this success by carefully coordinated plans involving the Emir of
Katsina, district heads and the people of the community in carrying out the
intervention in the districts where they worked. This is a good illustration of
how to implement public health control strategies for an epidemic disease in a
low resource setting even though this was almost half a century ago and public
health efforts in Nigeria was still in the infancy stages.
REFERENCES
Blakebrough, I.S., et. al., 1982. The epidemiology of infections due to Neisseria meningitidis and Neisseria lactamica in a Northern Nigerian community. The Journal of Infectious Diseases, 146(2), pp.626-637.
Greenwood, B., 2006. 100 years of epidemic meningitis in West Africa – has
anything changed? Tropical Medicine &
International Health, 11, pp.773–780.
Vollum, R.L. and Griffiths, R.W., 1962. An experiment in the prevention of
meningococcal meningitis in Nigeria. Journal
of Clinical Pathology, 15, pp.50-53
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