title: The role of African buffalos (Syncerus caffer) in the maintenance of foot-and-mouth disease in Uganda.
abstract: BACKGROUND
  To study the role of African buffalos (Syncerus caffer) in the maintenance of foot-and-mouth disease in Uganda, serum samples were collected from 207 African buffalos, 21 impalas (Aepyceros melampus), 1 giraffe (Giraffa camelopardalis), 1 common eland (Taurotragus oryx), 7 hartebeests (Alcelaphus buselaphus) and 5 waterbucks (Kobus ellipsiprymnus) from four major National Parks in Uganda between 2005 and 2008. Serum samples were screened to detect antibodies against foot-and-mouth disease virus (FMDV) non-structural proteins (NSP) using the Ceditest® FMDV NS ELISA. Solid Phase Blocking ELISAs (SPBE) were used to determine the serotype-specificity of antibodies against the seven serotypes of FMDV among the positive samples. Virus isolation and sequencing were undertaken to identify circulating viruses and determine relatedness between them.
  
  
  RESULTS
  Among the buffalo samples tested, 85% (95% CI = 80-90%) were positive for antibodies against FMDV non-structural proteins while one hartebeest sample out of seven (14.3%; 95% CI = -11.6-40.2%) was the only positive from 35 other wildlife samples from a variety of different species. In the buffalo, high serotype-specific antibody titres (≥ 80) were found against serotypes O (7/27 samples), SAT 1 (23/29 samples), SAT 2 (18/32 samples) and SAT 3 (16/30 samples). Among the samples titrated for antibodies against the four serotypes O, SAT 1, SAT 2 and SAT 3, 17/22 (77%; CI = 59.4-94.6%) had high titres against at least two serotypes.FMDV isolates of serotypes SAT 1 (1 sample) and SAT 2 (2 samples) were obtained from buffalo probang samples collected in Queen Elizabeth National Park (QENP) in 2007. Sequence analysis and comparison of VP1 coding sequences showed that the SAT 1 isolate belonged to topotype IV while the SAT 2 isolates belonged to different lineages within the East African topotype X.
  
  
  CONCLUSIONS
  Consistent detection of high antibody titres in buffalos supports the view that African buffalos play an important role in the maintenance of FMDV infection within National Parks in Uganda. Both SAT 1 and SAT 2 viruses were isolated, and serological data indicate that it is also likely that FMDV serotypes O and SAT 3 may be present in the buffalo population. Detailed studies should be undertaken to define further the role of wildlife in the epidemiology of FMDV in East Africa.
authors.affiliation: Ministry of Agriculture, Animal Industry and Fisheries, P.O. Box 513, Entebbe, Uganda.
authors.forename: Chrisostom
authors.initials: C
authors.lastname: Ayebazibwe
authors.forename: Frank N
authors.initials: FN
authors.lastname: Mwiine
authors.forename: Kirsten
authors.initials: K
authors.lastname: Tjørnehøj
authors.forename: Sheila N
authors.initials: SN
authors.lastname: Balinda
authors.forename: Vincent B
authors.initials: VB
authors.lastname: Muwanika
authors.forename: Anna R
authors.initials: AR
authors.lastname: Ademun Okurut
authors.forename: Graham J
authors.initials: GJ
authors.lastname: Belsham
authors.forename: Preben
authors.initials: P
authors.lastname: Normann
authors.forename: Hans R
authors.initials: HR
authors.lastname: Siegismund
authors.forename: Soren
authors.initials: S
authors.lastname: Alexandersen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000866:Antelopes / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D002020:Buffaloes / Q000097:blood; D004197:Disease Reservoirs / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005536:Foot-and-Mouth Disease / Q000453:epidemiology*; D029544:Foot-and-Mouth Disease Virus / Q000145:classification / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012703:Serotyping; D014454:Uganda / Q000453:epidemiology
chemical_list: D000914:Antibodies, Viral