Back to overview

The "one medicine": Molecular epidemiology of zoonotic Mycobacterium bovis in relation to host genetic variation in African animal hosts

English title The "one medicine": Molecular epidemiology of zoonotic Mycobacterium bovis in relation to host genetic variation in African animal hosts
Applicant Zinsstag Jakob
Number 107559
Funding scheme Project funding (Div. I-III)
Research institution Abt. öff. Gesundheitswesen und Epidemiologie Schweizerisches Tropen- und Public Health-Institut
Institution of higher education University of Basel - BS
Main discipline Molecular Biology
Start/End 01.05.2005 - 30.04.2008
Approved amount 227'000.00
Show all

All Disciplines (3)

Molecular Biology
Infectious Diseases

Keywords (16)

molecular epidemiology; mycobacterium bovis; mycobacterial interspersed repetitive units; variable number of tandem repeats; microsatellites; cattle; Africa; zoonosis; spoligotype; region deletion; Chad; Mali; Ethiopia; Senegal; animal health; public health

Lay Summary (English)

Lay summary
Bovine tuberculosis is a form of tuberculosis transmissible between animals and humans. It is caused by the bacteria Mycobacterium bovis, which is a member of the so called “Tuberculosis complex”, a group of bacteria, among which the most prominent member is Mycobacterium tuberculosis, the main causing agent of human tuberculosis. Bovine tuberculosis was eliminated from many industrialized countries, also from Switzerland by well coordinated elimination campaigns of infected cattle. Since the introduction of the pasteurization of milk, the transmission of bovine tuberculosis from cattle to humans could be largely interrupted. However, bovine tuberculosis remains an important and under-investigated problem of many developing countries, particularly those with large cattle populations. Almost nothing is known about the transmission of bovine tuberculosis in many African countries. This project aims to investigate the molecular epidemiology of the distribution and spread of bovine tuberculosis in Africa. For this we established research partnerships with African research institutions in Chad, Mali, Senegal, Ethiopia and Algeria, but also with partners in the United Kingdom. Thereby Swiss doctoral students work together with African doctoral students in a partnership way. The main advantage of this way of collaboration is its added value of combining cutting edge molecular typing and local African knowledge. By the use of molecular markers, tiny portions of the genetic material of this bacterium, we can identify strains of bacteria, say under-groups or family members in the same way as we would distinguish different human individuals by their finger prints. In this way, we could in collaboration with our partners, identify a specific group of bacteria (a clonal complex), which appears to be geographically localized to sub-Saharan Central- and West Africa. This closely related group of bacteria lacks a specific portion of the genetic material, which we call Region deletion Af1 (RDAf1). Further analysis showed a distinct group of RDAf1 of bacteria in Mali. This is the first time that Malian bovine tuberculosis strains have been characterized. Strains from Algeria and to a lesser degree from Mali are related to European strains. More research is needed to understand to which extend bovine tuberculosis has been brought to Africa from Europe or if there exists true, not important African bovine tuberculosis. Our work helps also to understand how bovine tuberculosis spreads in Africa and we have indications that there might be a spread of the disease from East to West. Other work looks at the diagnosis of bovine tuberculosis in living African cattle. An important finding is that the standard test, which is called the “tuberculin” test, remains still the best field test under African conditions, but we suggest a modification of the reading of the test to make it more suitable for African conditions. Testing living animals is important in view of future control programs against this disease in Africa, which we hope to develop together with a large network of 24 countries.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants