A meningitis outbreak in Nigeria has killed 745 people since November 2016 in over 8,000 reported cases.
The outbreak left the federal government and health officials struggling to contain the specific strain – meningitis serotype C - which has been reported in 181 local councils in 22 of Nigeria’s 36 states, including the Federal Capital Territory.
The 6 worst hit states are all in northern Nigeria: Katsina, Kebbi, Sokoto, Niger, Yobe and Zamfara, where the first case of the 2016/2017 meningitis C epidemic was reported.
The governor of Zamfara, Abdulaziz Yari, attributed the outbreak in an interview to “God’s anger”.
“There is no way fornication will be so rampant and God will not send a disease that cannot be cured,” the governor was reported to have said in Hausa. He was widely criticised for his comments.
This factsheet sets out scientific explanations for why Zamfara and other parts were badly hit, as well as the disease's causes, symptoms and vaccines available.
Regular outbreaks in African meningitis belt
A large part of Nigeria falls in the African meningitis belt, which stretches from Senegal to Ethiopia across 26 countries. For the past 100 years, periodic waves of meningitis have claimed countless lives. These waves start in the dry season between December to June and can last up to 3 years.
Between 1995 and 2014, the World Health Organisation documented more than 900,000 cases in the region and over 90,000 deaths, while between 10% and 20% of survivors developed chronic neurological conditions.
Researchers have shown there is an environmental connection to outbreaks along the meningitis belt. A 2003 study conducted by researchers at the Liverpool School of Tropical Medicine found that “absolute humidity, dust and rainfall profiles, land-cover type and population densities were independently associated with the location of [meningitis] epidemics”.
The Meningitis Vaccine Project, a partnership between the World Health Organization and the non-profit health organisation PATH, points out that concurrent infections and demographic conditions, such as when large parts of the population go on pilgrimages or travel to regional markets, further add to the burden.
Less common bacteria type driving current epidemic
Meningococcal meningitis is a bacterial form of meningitis which infects the membrane of the brain. This cerebrospinal infection has a 50% fatality rate when left untreated and can lead to brain damage, deafness and epilepsy. Children and adolescents are particularly vulnerable to the disease.
Different types of bacteria can cause meningitis, but Neisseria meningitidis has been identified as the major culprit in most of Nigeria’s epidemics. The bacteria is carried in the throat and can overpower the body's defences, letting the infection spread through the bloodstream to the victim’s brain. It is transmitted by drops of respiratory or throat secretions from people carrying the bacteria.
The bacteria has 12 subgroups and 6 of them - serotypes A, B, C, W, X and Y - cause epidemics, with type A epidemics being the most common in the African meningitis belt. (Note: Other, less deadly forms of meningitis are caused by viruses, fungi, amoebas and other parasites.)
Zamfara’s governor was quoted as saying that “because people refused to stop their nefarious activities, God now decided to send type C virus, which has no vaccination”.
But the present meningitis C epidemic is not new. There were reported cases of the strain in Nigeria in 2013, 2014 and 2015 - and a vaccine is available.
The symptoms of meningitis C are similar to those of the other serotypes. According to WHO, the obvious symptoms are a stiff neck, fever, light sensitivity, headaches and vomiting. The symptoms are usually observed between day 2 and day 10 of infection.
Other symptoms of meningitis include:
Children made up half of cases
The most recent large-scale epidemic within the African meningitis belt was reported in 2009, hitting mainly Nigeria and Niger Republic. Over 80,000 cases were reported in both countries and in Nigeria alone, 175 districts crossed the epidemic threshold of 10 reported cases per 100,000 people per week.
In 1996, one of Nigeria’s worst-ever outbreaks of cerebrospinal meningitis was recorded, with a fatality rate of just over 10%. In the first 6 months of that year, 11,717 people reportedly died out of 109,580 cases recorded.
During the current epidemic, children between 5 and 14 have been the most affected, accounting for more than half the cases.
Reasons why northwest Nigeria has been worst hit
Each state in the region has reported and confirmed meningitis cases, registering 7,618 cases out of the 8,057 cases as at 12 April 2017. Most deaths - 457 of the 745 deaths - were recorded in Zamfara state.
Poverty, poor health facilities and religious practices - apart from environmental risks - may also have contributed to the prevalence of meningitis in the region. In a 2010 poverty profile report by the Nigeria Bureau of Statistics, the region was listed as the country’s the poorest - with an absolute poverty rate of 70%.
Vaccination only started in April 2017
Commercial quantities of vaccines needed to fight meningitis C are not available or produced locally, so Nigeria has had to make special plans with international health partners to get vaccination doses required to check the epidemic.
The WHO international coordinating group on vaccine provision for epidemic meningitis control is believed to have just about 4 million doses in storage. At the beginning of April, about 500,000 doses of meningitis C vaccines have reportedly been distributed to affected states while about 820,000 doses are expected from the United Kingdom.
However, vaccine distribution has been marred in controversy in some affected areas as batches of vaccines are being diverted by officials and sold illegally to people.
Nigeria warned of impending outbreak
Sadly, many deaths could have been averted. Countries in Africa's meningitis belt - particularly Nigeria - were warned of impending meningitis C outbreaks, a report of a meeting convened by the WHO in October 2015 in Geneva shows.
“There is a high risk of continuing expansion of serotype C epidemics of meningococcal meningitis in 2016 and future years across the meningitis belt of sub-Saharan Africa,” the participants concluded.
The meeting - which was attended by WHO experts, local health officials, US’ Centres for Disease Control and representatives of international aid agencies - recommended that:
Enhanced surveillance should be maintained in all countries of the meningitis belt,
Nigeria and the Democratic Republic of Congo shore up their relatively weak surveillance systems,
High priority should be given by partners to increasing the stockpile of meningitis C vaccines.