Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Meningitis: effectiveness of preventive vaccination demonstrated

06.06.2007
Meningitis epidemics caused by the pathogen Nesseiria meningitis (or meningococcus) provoke high mortality in children and young people under 20 years of age in sub-Saharan Africa. They rage during periods of drought from January to April, in the area known as the “Meningitis Belt”

Two types of vaccine are currently on the market: the polysaccharide vaccine and the conjugated vaccine. The polysaccharide form, elaborated from a sugar present at the surface of the meningococcus provides only partial, temporary immunity in very young children (2).

The conjugated vaccine, however, is based on a combination between this same sugar and an antigenic protein and renders an effective durable immunity. It could therefore be used in a routine preventive vaccination campaign. But it is costly. Its high price, at 11 to 22 euros per dose, means it remains inaccessible for African countries. These have available only the polysaccharide vaccine, less expensive at 0.3 to 0.5 euro, but which, because of its low immunity capacity, is generally kept only for emergency vaccinations, when epidemics occur.

IRD researchers have been running a follow-up study of the people of the Niakhar region (located 150 km from Dakar, in Senegal) for more than 40 years. They looked into the question of the ability of the polysaccharide vaccine to prevent the occurrence of meningitis cases during epidemics in the course of subsequent years. To do that, they made use of results of two vaccination campaigns conducted with this vaccine by the Senegalese health services. One of these was run in 1996 in 8 of the 30 villages that make up the Niakhar region, the other in 1999, in the whole of the study area, hit be a series of epidemics between 1998 and 2000.

Using quarterly censuses carried out since 1983, the researchers collected then analysed data on children’s state of health and vaccine status. They could therefore make comparisons between the different villages regarding the number of cases of meningitis that broke out, in particular in the years that followed the 1996 vaccination campaign (3).

Their investigation revealed that in the villages vaccinated at that date, two to three times fewer subjects were recorded as suffering from the disease. The polysaccharide vaccine could help avoid up to 72% of cases in subsequent epidemics.

These results speak in favour of adopting a strategy of routine vaccination using this vaccine – whenever no other vaccine is available – in order to prevent meningococcus meningitis epidemics in this region of Africa. However, a conjugated vaccine which should be sold at less than 1$ (0.80 euro) per dose, is under development. Thanks to the full, durable immunity it confers right from early childhood, it is an ideal tool for a preventive vaccination strategy. Clinical trials initiated in 2006, notably in Niakhar, are continuing for a further 2 years in order to make sure that no undesirable side-effects occur after administration.

Marie Guillaume | EurekAlert!
Further information:
http://www.ird.fr

More articles from Health and Medicine:

nachricht New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM

nachricht A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>