Meningitis control in countries of the African meningitis belt, 2015
Lab resultws and conclusions below; full text is at http://www.who.int/wer/2016/wer9116.pdf?ua=1
On the lab results for N. meningitides in the meningitis belt, here are the figures from 2015;
Type A 77
Type B 1
Type C 1120
Type X 20
Type X 458
Other serotypes 82
The 2015 epidemic season was marked by the expansion of the N.m. C serogroup that caused 2 large scale outbreaks in Nigeria and Niger. Sporadic cases of N.m. C were also reported in Burkina Faso, Côte d’Ivoire and Mali. It is foreseen that N.m. C will continue to expand in the coming years.
The re-emergence of N.m. C in Africa, is considered to be likely due to natural evolutionary changes in the bacteria, rather than serogroup replacement, following introduction of MACV.8 Since 2010, 16 of the 26 countries of the African meningitis belt have introduced MACV. No N.m. A epidemics have occurred in areas where vaccination with MACV has been implemented.
Overall, there is a continuing dramatic decrease in the numbers of N.m. A cases in these countries. While the burden of meningitis in the African belt has steadily decreased with the success of the MACV introduction, at least 10 000 suspected cases and numerous outbreaks due to other pathogens continue to occur each year.
In 2015, over 20 000 people were affected by meningitis, with 26 districts facing epidemic situations, mainly due to N.m. C. In 2012 a similar situation occurred (20 062 cases, 33 districts in epidemic predominantly due to N.m. W). As vaccine manufacturers are phasing out production of the more affordable meningococcal polysaccharide vaccines in favour of the more effective but prohibitively expensive conjugate vaccines, the means to control these epidemics is seriously compromised.5
Until the development of an affordable multivalent conjugate vaccine is made available, WHO and partners will continue to bolster affordable, appropriate vaccine supply in order to support countries’ efforts to control meningitis outbreaks. These epidemiological changes emphasize the need for continuing to strengthen surveillance of meningitis and in particular the laboratory component. The 2 main surveillance strategies, i.e. the enhanced surveillance covering all countries for outbreak detection and the case-based surveillance to measure the impact of MACV and monitor trends in N.m. serogroups are necessary and complementary to adapt the outbreak response and inform preventive vaccination strategies.