Bacillus anthracis Diversity and Geographic Potential across Nigeria, Cameroon and Chad: Further Support of a Novel West African Lineage.
Zoonoses, diseases affecting both humans and animals, can exert tremendous pressures on human and veterinary health systems, particularly in resource limited countries. Anthrax is one such zoonosis of concern and is a disease requiring greater public health attention in Nigeria. Here we describe the genetic diversity of Bacillus anthracis in Nigeria and compare it to Chad, Cameroon and a broader global dataset based on the multiple locus variable number tandem repeat (MLVA-25) genetic typing system. Nigerian B. anthracis isolates had identical MLVA genotypes and could only be resolved by measuring highly mutable single nucleotide repeats (SNRs). The Nigerian MLVA genotype was identical or highly genetically similar to those in the neighboring countries, confirming the strains belong to this unique West African lineage. Interestingly, sequence data from a Nigerian isolate shares the anthrose deficient genotypes previously described for strains in this region, which may be associated with vaccine evasion. Strains in this study were isolated over six decades, indicating a high level of temporal strain stability regionally. Ecological niche models were used to predict the geographic distribution of the pathogen for all three countries. We describe a west-east habitat corridor through northern Nigeria extending into Chad and Cameroon. Ecological niche models and genetic results show B. anthracis to be ecologically established in Nigeria. These findings expand our understanding of the global B. anthracis population structure and can guide regional anthrax surveillance and control planning.
Spatial Epidemiology & Ecology Research Lab, Department of Geography, University of Florida, Gainesville, Florida, United States of America; Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America.
Jason K
JK
Blackburn
Bacterial Research Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
Moses Ode
MO
Odugbo
Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America.
Matthew
M
Van Ert
MRI Global, Palm Bay, Florida, United States of America.
Bob
B
O'Shea
Spatial Epidemiology & Ecology Research Lab, Department of Geography, University of Florida, Gainesville, Florida, United States of America.
Jocelyn
J
Mullins
Vincent
V
Perreten
Institute of Veterinary Bacteriology, University of Berne, Berne, Switzerland.
Vincent
V
Perrenten
Laboratoire de Recherches Vétérinaires et Zootechniques, N'Djaména, Chad.
Angaya
A
Maho
Department of Environmental Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America.
Martin
M
Hugh-Jones
Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America; MRI Global, Palm Bay, Florida, United States of America.
Ted
T
Hadfield
D000818:Animals; D000881:Anthrax / Q000453:epidemiology / Q000382:microbiology* / Q000662:veterinary*; D001408:Bacillus anthracis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D015373:Bacterial Typing Techniques; D002163:Cameroon / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D002596:Chad / Q000453:epidemiology; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D018598:Minisatellite Repeats; D008969:Molecular Sequence Data; D009549:Nigeria / Q000453:epidemiology; D010802:Phylogeny