The consortium also monitors the emergence of disease and epidemics due to other serogroups. Learn more about MenAfriNet external icon. Epidemics of meningococcal meningitis in Africa can affect hundreds of thousands of people and kill many thousands. CDC contributed to development of an inexpensive vaccine. CDC is now working with partners to ensure it is used where needed most and evaluated for effectivene… more. Top of Page. Skip directly to site content Skip directly to page options Skip directly to A-Z link.
Meningococcal Disease. However, some comparisons are possible and illustrative. The incidence of suspected meningitis in Burkina Faso was 61 cases per population in — [ 2 ], compared to In this analysis, the highest NmX incidence was in Togo in 7. However, pneumococcal meningitis incidence in Burkina Faso in — 32 was twice that reported in 3 districts in — 14 [ 29 ], and in Chad, suspected meningitis incidence in The experience of the 5 key high-risk MenAfriNet countries in conducting high-quality meningitis surveillance demonstrates that long-term investment in case-based surveillance is a valuable platform both for monitoring evolving meningitis epidemiology and for evaluating the effectiveness of bacterial meningitis vaccines, especially MACV integration into routine immunization programs, pneumococcal conjugate vaccines, Hib conjugate vaccines, and a potential future multivalent meningococcal conjugate vaccine [ 25 ].
This network collects high-quality, case-based meningitis data in a region where the collection of high-quality surveillance data is a challenge, but is extremely important due to the high disease burden.
These case-based data are a critical supplement to the conventional aggregate surveillance reporting via the Integrated Disease Surveillance and Response framework [ 8 ], as well as to enhanced meningitis surveillance being conducted elsewhere in the meningitis belt [ 31 ]. Therefore, maintenance of case-based surveillance in key high-performing meningitis belt countries beyond the completion of the MenAfriNet project will help ensure continued availability of high-quality data to inform vaccine policy [ 32 ].
These results support other analyses demonstrating the continued remarkable impact of MACV on both NmA carriage and disease throughout the meningitis belt [ 4 , 5 ].
This analysis indicates that regional meningitis epidemiology continues to change following MACV introduction. However, these declines were more pronounced among other PCV13 serotypes than for serotype 1, which continues to cause outbreaks in the region [ 40 ], indicating a potential need to reevaluate pneumococcal meningitis prevention and response strategies in the belt.
Despite the high-quality surveillance conducted in the 5 MenAfriNet countries, challenges to case-based meningitis surveillance in these countries remain. A perennial challenge is specimen transport. However, creative approaches to tracking specimens using barcodes and a cloud-based system in Burkina Faso may provide insights on how to improve this process and may be scaled up to other countries [ 41 ].
Ensuring that all suspected meningitis cases are reported, nearly all suspected meningitis cases have a CSF specimen collected, and every CSF specimen is received and tested at a national reference laboratory via culture or rt-PCR is key to high-quality case-based surveillance. Additionally, this case-based surveillance network only focuses on the clinical presentation of meningitis and does not capture cases with nonmeningitis presentations such as meningococcemia [ 42 ], therefore presented incidences are minimal estimates of the full burden of invasive disease due to these pathogens.
Despite these challenges, our reported incidence rates adjust for changes in culture and rt-PCR testing capacity over time and likely reflect true trends in pathogen-specific incidences for meningitis.
An immense effort has been invested in MACV vaccination campaigns in MenAfriNet countries and elsewhere in the belt, resulting in major successes in mobilizing international and local communities and encouraging high vaccine uptake, and in an extraordinary and unprecedented reduction in meningitis burden and NmA transmission.
However, the data emphasize the importance of non-NmA serogroups and pneumococcal meningitis, and suggest that intensive meningitis surveillance with high levels of laboratory confirmation in a number of countries is needed to provide a representative picture of the dynamic regional epidemiology.
Continued thoughtful and successful integration of MACV and PCV into childhood routine immunization programs, along with long-term investments in surveillance and a future multivalent meningococcal conjugate vaccine, could help to ensure that a goal of defeating meningitis by is met [ 32 , 43 ].
Supplementary materials are available at The Journal of Infectious Diseases online. Consisting of data provided by the authors to benefit the reader, the posted materials are not copyedited and are the sole responsibility of the authors, so questions or comments should be addressed to the corresponding author.
The MenAfriNet Consortium www. The authors thank all MenAfriNet partners, including participating national health systems, health centers, and laboratories. The findings and conclusions of this report are those of the authors and do not necessarily represent the official position of CDC or WHO. Financial support. This work was funded by the MenAfriNet consortium www.
Potential conflicts of interest. All other authors report no potential conflicts of interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed. Greenwood B. Manson lecture. Meningococcal meningitis in Africa. Google Scholar. Serogroup A meningococcal conjugate vaccination in Burkina Faso: analysis of national surveillance data. Lancet Infect Dis ; 12 : — Status of the rollout of the meningococcal serogroup A conjugate vaccine in African meningitis belt countries in J Infect Dis ; Suppl 4 : S — 7.
Impact of MenAfriVac in nine countries of the African meningitis belt, an analysis of surveillance data. Lancet Infect Dis ; 17 : — Impact of the serogroup A meningococcal conjugate vaccine, MenAfriVac, on carriage and herd immunity. Clin Infect Dis ; 56 : — MenAfriNet: a network supporting case-based meningitis surveillance and vaccine evaluation in the meningitis belt of Africa.
J Infect Dis ; Suppl 4 :S— Nationwide trends in bacterial meningitis before the introduction of valent pneumococcal conjugate vaccine-Burkina Faso, — PloS One ; 11 : e World Health Organization. Technical guidelines for integrated disease surveillance and response in the African region. Brazzaville: WHO , Google Preview. Standard operating procedures for case-based surveillance of meningitis, preparedness and response to meningitis epidemics.
Improving case-based meningitis surveillance in 5 countries in the meningitis belt of sub-Saharan Africa, — J Infect Dis ; Suppl 4 : S — Standard operating procedures for enhanced meningitis surveillance in Africa. Laboratory methods for the diagnosis of meningitis caused by Neisseria meningitidis , Streptococcus pneumoniae , and Haemophilus influenzae , 2nd ed. Geneva : World Health Organization , J Clin Microbiol ; 45 : — 6.
Clinical validation of multiplex real-time PCR assays for detection of bacterial meningitis pathogens. J Clin Microbiol ; 50 : — 8. Impact of valent pneumococcal conjugate vaccine on pneumococcal meningitis—Burkina Faso, — MenAfriNet Consortium. Bacterial meningitis epidemiology and return of Neisseria meningitidis serogroup A cases in Burkina Faso in the five years following MenAfriVac mass vaccination campaign.
PLoS One ; 12 : e Metrics details. Bacterial meningitis occurs worldwide but Africa remains the most affected continent, especially in the "Meningitis belt" that extends from Senegal to Ethiopia.
Three main bacteria are responsible for causing bacterial meningitis, i. Since , other Nm serogroups including W, X and C have also been responsible for causing epidemics. Based on basic spatio-temporal methods, and a years database of reported suspected meningitis cases and death from the World Health Organization, we used both geographic information system and spatio-temporal statistics to identify the major localizations of meningitis epidemics over this period in Africa.
Bacterial meningitis extends today outside its historical limits of the meningitis belt. Since the introduction of MenAfrivac vaccine in , there has been a dramatic decrease in NmA cases while other pathogen species and Nm variants including NmW, NmC and Streptococcus pneumoniae have become more prevalent reflecting a greater diversity of bacterial strains causing meningitis epidemics in Africa today.
Bacterial meningitis remains a major public health problem in Africa today. Formerly concentrated in the region of the meningitis belt with Sub-Saharan and Sudanian environmental conditions, the disease extends now outside these historical limits to reach more forested regions in the central parts of the continent.
With global environmental changes and massive vaccination targeting a unique serogroup, an epidemiological transition of bacterial meningitis is ongoing, requiring both a better consideration of the etiological nature of the responsible agents and of their proximal and distal determinants. Peer Review reports.
Bacterial meningitis affects all countries of the world but primarily Africa especially the "Meningitis belt" that extends from Senegal near the Atlantic coast to Ethiopia and Somalia on the seashores of the Red Sea and the Indian Ocean [ 1 ].
Apart from epidemics, at least 1. Three main bacterial species are responsible for causing meningitis, Streptococcus pneumoniae Sp , Haemophilus influenzae type b Hib and Neisseria meningitidis Nm most likely to cause major epidemics of cerebrospinal meningitis CSM [ 3 ]. Within the traditional meningitis belt, major epidemics occur every 5 to 12 years, with an attack rate of up to cases per , individuals [ 10 ]. Research studies carried out at the interface between epidemiology and climatology since the mid-XXth century have demonstrated the existence of a strong seasonal pattern of epidemics, which occurs during the dry season [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ] i.
During this period, the dry winds of the Harmattan blow in Western Africa, carriers of dust and sand particles, may irritate the mucous membranes of the upper respiratory tract for people living in these regions.
It should be noted that Neisseria meningitidis has the human oropharynx as an ecological niche. When the upper respiratory tract is colonized by the bacteria without causing disease, it is called a carriage state. On the other hand, when the oropharyngeal mucosa is attacked for example by the sand wind, the bacteria can cross into the general circulation and thus cause disease a failing or dysfunctional relationship between the bacteria and the host.
The bacterium is transmitted from person to person through droplets of respiratory or pharyngeal secretions and is often manifested by fever, stiff neck, headache, sometimes sensitivity to light and vomiting… [ 18 , 19 , 20 ]. The management of bacterial meningitis is both preventive vaccines and curative antibiotics. The recommended antibiotics are currently penicillin, ampicillin, chloramphenicol and ceftriaxone in monotherapy, especially in low-income countries [ 23 , 24 , 25 ].
The conjugate vaccine MenAfriVac was developed rapidly and has been deployed extensively since in all countries of the belt, with the goal of protecting populations against the most prevalent meningococcal meningitis serogroup, i.
Vaccination campaigns have been a great success particularly in Burkina Faso, Mali and Niger in Nearly 20 million people aged 1 to 29 years were vaccinated during these campaigns and the following epidemic season showed a dramatic reduction of NmA cases [ 29 ].
In addition, some epidemics of meningitis have been shown to occur with irregular cycles within some countries of the belt [ 9 , 30 ], suggesting that vaccine campaigns could have affected the spatio-temporal dynamics of meningitis spread or that ecological or evolutionary interferences could have happened between the different co-circulating bacterial strains causing meningitis. At the same time, several other African countries located outside the so-called meningitis belt have faced sporadic but significant epidemics of meningitis [ 31 , 32 , 33 ].
A possible extension of the African meningitis belt to other African territories has raised the possibility that it may become necessary to extend vaccination programs beyond the previously prioritized targeted countries. In one previous study, we show that an interplay of different geographical and environmental variables as latitude, longitude and socio-economic drivers are important to consider in the epidemiology of bacterial meningitis epidemics in DRC which is considered outside the meningitis belt [ 34 ].
In this study based on a year time-series of suspected meningitis cases and death reported in the 53 different states in Africa by the World Health Organization WHO , we provide a first descriptive analysis of continent-wide meningitis epidemics in order to characterize the existence of spatio-temporal patterns of transmission over this period.
Data with pathogen identification is also illustrated. This work allows to extract several important conclusions about the circulation of meningitis pathogens and their recent African continent-wide spread, and to propose recommendations for the surveillance and control of these severe human infections all over Africa. With its 54 independent countries and a population of approximately billion of people with a density of 40 inhabitants per km 2 , Africa is currently considered to be the second largest and most populated continent after Asia [ 35 ].
The topography of the continent is dominated by uplands cut in hard rocks and often lined with cliffs. The majority of the uplands can reach a height of m. There are also plains and higher mountains which are mainly concentrated in the eastern part of the continent. The climate is determined by the crossing of the Equator line and the Tropics. There are four types of climate: 1 the equatorial climate around the Equator with two categories, a humid condition in the center and the west mm to over mm of water per year and a drier one in the east rainfall less than 1 mm ; 2 the tropical climate between the tropics, except the equatorial zone with two subclimate types, a wet type to mm of rainfall per year with 3 to 6 months of dry season and a dry type between to mm of rain per year with 6 to 9 months of dry season; 3 the desert climate north of the Tropics, i.
Each climate has a characteristic type of vegetation or biome. The equatorial climate is characterized by a dense rainforest, a developed fauna and flora. The vegetation of the tropical climate is distinguished from the others by the quasi-absence of forest or presence of the savannah or savannah-like ecosystems while that of the Mediterranean climate, by pine forests, scrubland and chaparral, and the desert climate by a dry to very dry, sparse or absent savannah [ 36 , 37 ].
Meningitis has been associated with the sub-Saharan and Sudanian, desert-like and dry-savannah, environments, thus suggesting that bacterial meningitis is associated with the environmental conditions prevailing in those types of ecosystems [ 38 , 39 ].
In the context of public health actions related to bacterial meningitis, the epidemiological surveillance currently carried out in sub-Saharan and Sudanian Africa in general and more particularly in the countries of the meningitis belt has the ultimate goal of contributing to reducing morbidity and mortality linked to these infections.
We collected the annually numbers of suspected cases and deaths due to meningitis reported during the meningitis epidemics periods from the different national health systems to WHO using the different following official websites pages consulted on May 9, Weekly Epidemiological Record accessed 9. We obtained data on suspected cases and deaths of meningitis between and , as defined according to WHO guidelines [ 2 ] at the health area spatial scale in the different countries. We also collected additional data from previous research on meningitis epidemics in Africa from to Kante, We obtained the database of confirmed cases from to in Africa from WHO, which presents the information about all CSF samples received for meningitis diagnosis, including the date of sampling, number of positive samples, the pathogen identified by Latex test, culture or polymerase chain reaction PCR.
Due to the lack of data precision, only data from the years to were used in the present review. Spatial analyses of meningitis cases were performed with the softwares QGIS 2. Annual time-series of meningitis and death cases were also studied using the software Stata ver. From to , 2,, cases including , deaths were reported to WHO-AFRO in the 53 African countries during the meningitis epidemics period, with a mean case-fatality rate of 5.
The highest case numbers were reported in ,cases see Fig. Annual meningitis cases blue bars and death red line in Africa, — a , annual cases blue bars and deaths red lines of meningitis reported from to in countries within the belt b and outside the belt c. Countries are ranked from left to right according to the number of cases reported.
Out-of-the-belt, Ghana recorded the highest number of cases 70, cases, 2. The spatial distribution of meningitis epidemics from to , illustrated through years periods of time see Fig. During the s to the s, meningitis epidemics were distributed widely on the African continent, with almost all the countries of the continent reporting cases. Towards the end of the s and from the s, meningitis epidemics appeared to decline in the south of the continent and in Northern Africa see Fig.
From an epidemic point of view, the s to the present show a near-universal African continent-wide distribution of major epidemics, with the late s and s harboring the greatest outbreaks of major meningitis epidemics. From the s until now, epidemics seem less important and concentrated in the upper part of the meningitis belt and the central part of the continent Fig.
Spatial distribution of meningitis cases by country in Africa from to Note that meningitis cases information is unavailable for the period — The areas in grey illustrate the different countries belonging to the meningitis belt.
The distribution of 11, positive CSF samples is shown in Table 1. Nm accounted for During this period Sp and Hi represented Overall, meningitis cases were highly dominated by Nm with different strains over the period, with NmC and NmW dominating in terms of confirmed cases and progressively replacing NmA in both time and space.
Since , corresponding to the progressive introduction of MenAfrivac vaccine in Africa, there has been a downward trend in notifications of NmA. NmW and C and Sp increased from The NmC strain showed a peak of case notifications between and , and thus appears to have significantly increased in occurrence in Africa following the introduction of MenAfriVac. The Sp pathogen, for its part, also seems to be increasing in Africa over this period and experienced a peak of case notifications in and in Fig.
Time-series of bacterial meningitis pathogens identified in Africa from to a and from to after MenAfrivac b. Between and , it is evidenced that Western African countries, particularly Niger, Nigeria and Burkina Faso three countries of the meningitis belt and a country in Eastern Africa, i. Specifically, these five African countries appear today as an important cradle for the circulation of co-existing strains of bacteria causing meningitis Figs.
The differences observed in the spatial distribution of pathogen strains as listed on Figs. Symptoms in teens and young adults. Some countries recommend immunisations to protect his age group. For example, over 65s in the UK are routinely offered free [pneumococcal vaccination[CW3]].
Other countries such as the US also recommend a pneumococcal vaccine for this age group. Where you live in the world influences your risk of getting meningitis. Additionally, environmental factors such as smoke exposure can increase risk. Travel abroad may increase your risk of encountering meningitis causing bacteria. An up-to-date list of countries with potential risk can be obtained from www. The risk of catching meningitis is the highest in the world in an area of Sub-Saharan Africa known as the meningitis belt.
This area stretches from Senegal to Ethiopia and is prone to large outbreaks of disease known as epidemics as a result of warm and dusty winter winds which can damage mucous membranes in the lungs and throat, making it easier for meningitis causing bacteria to invade the body. Large epidemics of meningitis and septicaemia caused by meningococcal bacteria disease have been linked to the Hajj pilgrimage. Meningitis and septicaemia caused by meningococcal bacteria or Hib bacteria are considered infectious, although the vast majority of cases are isolated.
When there is a case of meningococcal or Hib meningitis and septicaemia certain people who have been in close contact with a case may need to take antibiotics or be vaccinated. If you have been in contact with someone with meningococcal meningitis or septicaemia and are worried about becoming ill or passing the infection to others, download our 'Am I at Risk? Robbie Jones contracted meningococcal disease at 21 months resulting in his left leg being amputated below the knee, the right leg above the knee and the loss of fingers on his left hand.
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