Natural immunity against serogroup X meningococci in Togo

Tackling a previously rare form of meningococcal disease

Scientific version
  • Researchers:
    Dr Gunnstein Norheim, Dr Judith Mueller, Dr Ray Borrow, Prof Andrew Pollard
  • Start Date:
    01 September 2009
  • Category:
    Prevention
  • Location:
    Oxford University, Oxford, UK, Agence de Médecine Préventive, Dapaong, Togo, Ministry of Health, Lomé, Togo
Natural immunity against serogroup X meningococci in Togo

Completed September 2011

This project addressed a major step in MenX vaccine research by studying naturally acquired immunity against serogroup X meningococcal bacteria in an area of Togo, West Africa that was affected by an outbreak in 2007. Scientists recruited healthy individuals from Togo, and compared their immunity to serogroup X meningococci with healthy control individuals from Burkina Faso and the UK within the same age range.

Investigating immunity and building capacity

Ethical approvals for this study were granted from relevant authorities in the U.K. and Togo in August 2009. In order to recruit healthy volunteers, the co-investigator from the Togolese Ministry of health engaged with the local city mayor local chiefs, presidents of neighbourhood committees and community leaders in Kara town, Togo. Local people were told about the project by use of a local radio station (Radio Tabala Kara) and “city criers” (gongonneurs), and encouraged to take part.

Following shipment of equipment to Kara, Togo, site preparation and communication with public health authorities, training of study recruiters, interviewers and technical personnel was undertaken. Over 20 staff, most of them from Togo, were involved in the field study operation coordinated by the Agence de Medicine Preventive (AMP). Nearly 300 healthy children and adults aged 3-5 years, 15-19 years and 20-25 years of age from the Kara region, Togo, were recruited. These individuals were also interviewed for known risk factors for contracting meningococcal disease. Data from questionnaires were entered into a database by AMP, and the samples were received in the U.K. in November 2009.

Samples from Togo, Burkina Faso and the UK were tested in several different ways:
•    The levels of antibodies against the surface coat (polysaccharide) and the surface proteins (outer membrane proteins) of serogroup X meningococci were developed
•    All blood samples were tested for their ability to kill serogroup X meningococci in the laboratory, a test that has been tailored for serogroup X bacteria by the PHE Vaccine Evaluation Laboratory in Manchester, U.K.

The samples were also used to help researchers purify the serogroup X polysaccharide from bacteria collected in Burkina Faso. This work was published in the journal Vaccine in July 2012.

In order to enhance meningitis surveillance in Togo, the project has also helped to work with Togolese health officials and doctors to build diagnostic capacity in the region. Local training in diagnostic techniques means that Togolese organisations are less dependant on outside help.

Altogether, the project has resulted in several scientific outputs that have stimulated more research on vaccine and diagnostics development. This will hopefully reduce the time until a vaccine and a diagnostic test targeting serogroup X N.meningitidis will be available for use in the African Meningitis Belt, and in this way benefit people affected by meningitis and septicaemia in the future.

Why is it important?

Meningitis epidemics periodically sweep across the African Meningitis Belt, which stretched from Senegal in the west to Ethiopia in the east, affecting up to 250,000 people in a single year.

These epidemics have been largely due to meningococcus A, and the introduction of a new MenA vaccine from December 2010 should reduce their severity. In the meantime, meningococcus X (previously a rare type of meningitis) has emerged as an increasingly important cause of the disease, and is not covered by any vaccine. This research has helped to start finding out if the strategy used for developing other successful meningitis vaccines, using the polysaccharide or ‘sugar coat’ of the bacteria, will work for meningococcus X

Papers and presentations

Emergence of serogroup X meningococcal disease in Africa: need for a vaccine.
Xie O1, Pollard AJ, Mueller JE, Norheim G.
Vaccine. 2013 Jun 12;31(27):2852-61. doi: 10.1016/j.vaccine.2013.04.036. Epub 2013 Apr 24.

Target amount

£20000.00

Donated so far

£0.00

So far £0.00 has been raised for this project including these recent donations...
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