Volume 98, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Little is known about the epidemiology of human brucellosis in sub-Saharan Africa. This hampers prevention and control efforts at the individual and population levels. To evaluate risk factors for brucellosis in northern Tanzania, we conducted a study of patients presenting with fever to two hospitals in Moshi, Tanzania. Serum taken at enrollment and at 4–6 week follow-up was tested by microagglutination test. Among participants with a clinically compatible illness, confirmed brucellosis cases were defined as having a ≥ 4-fold rise in agglutination titer between paired sera or a blood culture positive for spp., and probable brucellosis cases were defined as having a single reciprocal titer ≥ 160. Controls had reciprocal titers < 20 in paired sera. We collected demographic and clinical information and administered a risk factor questionnaire. Of 562 participants in the analysis, 50 (8.9%) had confirmed or probable brucellosis. Multivariable analysis showed that risk factors for brucellosis included assisting goat or sheep births (Odds ratio [OR] 5.9, 95% confidence interval [CI] 1.4, 24.6) and having contact with cattle (OR 1.2, 95% CI 1.0, 1.4). Consuming boiled or pasteurized dairy products was protective against brucellosis (OR 0.12, 95% CI 0.02, 0.93). No participants received a clinical diagnosis of brucellosis from their healthcare providers. The under-recognition of brucellosis by healthcare workers could be addressed with clinician education and better access to brucellosis diagnostic tests. Interventions focused on protecting livestock keepers, especially those who assist goat or sheep births, are needed.

[open-access] This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. Corbel MJ, , 2006. Brucellosis in Humans and Animals. Geneva, Switzerland: World Health Organization and Food and Agriculture Organization of the United Nations.
  2. Pappas G, Papadimitriou P, Akritidis N, Christou L, Tsianos EV, , 2006. The new global map of human brucellosis. Lancet Infect Dis 6: 9199. [Google Scholar]
  3. Crump JA, 2011. Invasive bacterial and fungal infections among hospitalized HIV-infected and HIV-uninfected adults and adolescents in northern Tanzania. Clin Infect Dis 52: 341348. [Google Scholar]
  4. Reddy EA, Shaw AV, Crump JA, , 2010. Community-acquired bloodstream infections in Africa: a systematic review and meta-analysis. Lancet Infect Dis 10: 417432. [Google Scholar]
  5. Rubach MP, Halliday JE, Cleaveland S, Crump JA, , 2013. Brucellosis in low-income and middle-income countries. Curr Opin Infect Dis 26: 404412. [Google Scholar]
  6. Corbel MJ, , 1997. Brucellosis: an overview. Emerg Infect Dis 3: 213221. [Google Scholar]
  7. McDermott J, Grace D, Zinsstag J, , 2013. Economics of brucellosis impact and control in low-income countries. Rev Sci Tech 32: 249261. [Google Scholar]
  8. Godfroid J, Cloeckaert A, Liautard JP, Kohler S, Fretin D, Walravens K, Garin-Bastuji B, Letesson JJ, , 2005. From the discovery of the Malta fever’s agent to the discovery of a marine mammal reservoir, brucellosis has continuously been a re-emerging zoonosis. Vet Res 36: 313326. [Google Scholar]
  9. McDermott JJ, Arimi SM, , 2002. Brucellosis in sub-Saharan Africa: epidemiology, control and impact. Vet Microbiol 90: 111134. [Google Scholar]
  10. Godfroid J, Nielsen K, Saegerman C, , 2010. Diagnosis of brucellosis in livestock and wildlife. Croat Med J 51: 296305. [Google Scholar]
  11. Pappas G, Akritidis N, Bosilkovski M, Tsianos E, , 2005. Brucellosis. N Engl J Med 352: 23252336. [Google Scholar]
  12. Shimol SB, Dukhan L, Belmaker I, Bardenstein S, Sibirsky D, Barrett C, Greenberg D, , 2012. Human brucellosis outbreak acquired through camel milk ingestion in southern Israel. Isr Med Assoc J 14: 475478. [Google Scholar]
  13. Chomel BB, DeBess EE, Mangiamele DM, Reilly KF, Farver TB, Sun RK, Barrett LR, , 1994. Changing trends in the epidemiology of human brucellosis in California from 1973 to 1992: a shift toward foodborne transmission. J Infect Dis 170: 12161223. [Google Scholar]
  14. Schelling E, Diguimbaye C, Daoud S, Nicolet J, Boerlin P, Tanner M, Zinsstag J, , 2003. Brucellosis and Q-fever seroprevalences of nomadic pastoralists and their livestock in Chad. Prev Vet Med 61: 279293. [Google Scholar]
  15. Crump JA, 2013. Etiology of severe non-malaria febrile illness in northern Tanzania: a prospective cohort study. PLoS Negl Trop Dis 7: e2324. [Google Scholar]
  16. Swai ES, Schoonman L, , 2009. Human brucellosis: seroprevalence and risk factors related to high risk occupational groups in Tanga Municipality, Tanzania. Zoonoses Public Health 56: 183187. [Google Scholar]
  17. John K, Fitzpatrick J, French N, Kazwala R, Kambarage D, Mfinanga G, MacMillan A, Cleaveland S, , 2010. Quantifying risk factors for human brucellosis in rural northern Tanzania. PLoS One 5: e9968. [Google Scholar]
  18. Shirima GM, Masola SN, Malangu ON, Schumaker BA, , 2014. Outbreak investigation and control case report of brucellosis: experience from livestock research centre, Mpwapwa, Tanzania. Onderstepoort J Vet Res 81. [Google Scholar]
  19. Government of Tanzania, 2002. Population and Housing Census. Dar es Salaam, Tanzania: National Bureau of Statistics, Government of Tanzania.
  20. Food and Agriculture Organization of the United Nations, Livestock Information, Sector Analysis and Policy Branch, 2005. Livestock Sector Brief. Tanzania: United Republic of Tanzania.
  21. Crump JA, 2011. Invasive bacterial and fungal infections among hospitalized HIV-infected and HIV-uninfected children and infants in northern Tanzania. Trop Med Int Health 16: 830837. [Google Scholar]
  22. Brown SL, Klein GC, McKinney FT, Jones WL, , 1981. Safranin O-stained antigen microagglutination test for detection of Brucella antibodies. J Clin Microbiol 13: 398400. [Google Scholar]
  23. CDC, 2010. Brucellosis Case Definition. Available at: https://wwwn.cdc.gov/nndss/conditions/brucellosis/case-definition/2010/. Accessed August 1, 2015.
  24. Vyas S, Kumaranayake L, , 2006. Constructing socio-economic status indices: how to use principal components analysis. Health Policy Plan 21: 459468. [Google Scholar]
  25. Saaty T, , 2008. Decision making with the analytic hierarchy process. Int J Serv Sci 1: 8398. [Google Scholar]
  26. Saaty T, , 1990. How to make a decision: the analytic hierarchy process. Eur J Oper Res 48: 926. [Google Scholar]
  27. Orsel K, Ho J, Hatfield J, Manyama M, Ribble C, van der Meer F, , 2015. Brucellosis serology as an alternative diagnostic test for patients with malaria-like symptoms. Tanzan J Health Res 17. [Google Scholar]
  28. Viana M, Shirima GM, John KS, Fitzpatrick J, Kazwala RR, Buza JJ, Cleaveland S, Haydon DT, Halliday JE, , 2016. Integrating serological and genetic data to quantify cross-species transmission: brucellosis as a case study. Parasitology 143: 821834. [Google Scholar]
  29. Asiimwe BB, Kansiime C, Rwego IB, , 2015. Risk factors for human brucellosis in agro-pastoralist communities of south western Uganda: a case-control study. BMC Res Notes 8: 405. [Google Scholar]
  30. Dean AS, Bonfoh B, Kulo AE, Boukaya GA, Amidou M, Hattendorf J, Pilo P, Schelling E, , 2013. Epidemiology of brucellosis and Q FEVER in linked human and animal populations in northern Togo. PLoS One 8: e71501. [Google Scholar]
  31. Ducrotoy M, Bertu WJ, Matope G, Cadmus S, Conde-Álvarez R, Gusi AM, Welburn S, Ocholi R, Blasco JM, Moriyón I, , 2015. Brucellosis in Sub-Saharan Africa: current challenges for management, diagnosis and control. Acta Trop 165: 179193. [Google Scholar]
  32. Bouley AJ, 2012. Brucellosis among hospitalized febrile patients in northern Tanzania. Am J Trop Med Hyg 87: 11051111. [Google Scholar]
  33. Cetinkaya Z, Aktepe OC, Ciftci IH, Demirel R, , 2005. Seroprevalence of human brucellosis in a rural area of western Anatolia, Turkey. J Health Popul Nutr 23: 137141. [Google Scholar]
  34. Osoro EM, 2015. Strong association between human and animal Brucella seropositivity in a linked study in Kenya, 2012–2013. Am J Trop Med Hyg 93: 224231. [Google Scholar]
  35. Makita K, Fèvre EM, Waiswa C, Kaboyo W, Bronsvoort BMdeC, Eisler MC, Welburn SC, , 2008. Human brucellosis in urban and peri-urban areas of Kampala, Uganda. Ann N Y Acad Sci 1149: 309311. [Google Scholar]
  36. Chipwaza B, Mugasa JP, Mayumana I, Amuri M, Makungu C, Gwakisa PS, , 2014. Community knowledge and attitudes and health workers’ practices regarding non-malaria febrile illnesses in eastern Tanzania. PLoS Negl Trop Dis 8: e2896. [Google Scholar]
  37. John K, Kazwala R, Mfinanga GS, , 2008. Knowledge of causes, clinical features and diagnosis of common zoonoses among medical practitioners in Tanzania. BMC Infect Dis 8: 162. [Google Scholar]
  38. Zhang HL, Mnzava KW, Mitchell ST, Melubo ML, Kibona TJ, Cleaveland S, Kazwala RR, Crump JA, Sharp JP, Halliday JE, , 2016. Mixed methods survey of zoonotic disease awareness and practice among animal and human healthcare providers in Moshi, Tanzania. PLoS Negl Trop Dis 10: e0004476. [Google Scholar]

Data & Media loading...

  • Received : 17 Feb 2017
  • Accepted : 08 Oct 2017
  • Published online : 11 Dec 2017

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error