A Quantitative Risk Assessment of Human Exposure to Brucellosis Through the Consumption of Contaminated Raw Cow Milk in Arusha, Tanzania
Keywords:
Brucellosis, Quantitative Risk Assessment, Raw Milk Consumption, Tanzania
Abstract
The study aimed to assess the risk of exposure to brucellosis through the consumption of cow milk in the Arusha region, of Tanzania. Primary data related to milk consumption was collected through a structured questionnaire from 400 cattle farmers. Data was directly coded and entered into IBM SPSS version 20 and analysed for frequencies and descriptive statistics. Stochastic Monte Carlo simulation in @risk Software (Version 8.1) platform was used to estimate the risk of human exposure to brucellosis through the consumption of contaminated milk. Results revealed that 96.5% of the population consumed milk in three (3) portions: morning, afternoon, and night. More than 70% of the people in the area consume 500ml-1000ml of milk daily. People in rural settings (71%) reported consuming raw milk, compared to 10% of people in urban settings. The probability of getting infected with Brucella through the consumption of raw milk was estimated at 0.64 (95%CI 0.333-0.861). The model also predicted the number of people likely to get infected with Brucella in Arusha region in a one-year consumption period to be 1,084,358 (95%CI: 565,000-1458,000) out of 1,694,310 people following consumption of contaminated raw milk. The risk of exposure was estimated to be high when dairy cows were infected with Brucella at the farm and when the milk portions were consumed raw. The risk of human exposure to the brucella pathogen is high. To reduce the risk of human exposure, there is a need to create awareness about brucellosis in the study communities concerning how the disease is transmitted to humans, its associated effects, and the preventive and control measures. Further studies are required to assess the risk of exposure to brucellosis through other pathways, such as the consumption of soft cheese and contact with cattle.References
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38. Pappas G, Papadimitriou P, Akritidis N, Christou L, Tsianos EV. The new global map of human brucellosis. 6(February), 91–99; 2006.
39. Spink W. Family studies on Brucellosis. 127–140; 1954.
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2. Alonso S, Dohoo I, Lindahl J, Verdugo, C, Akuku I, Grace D. Prevalence of tuberculosis, brucellosis and trypanosomiasis in cattle in Tanzania : a systematic review and meta-analysis. 17(1).https://doi.org/10.1017/S146625231600013X; 2016.
3. Bayramoglu G, Ozalp VC, Oztekin M, Arica MY. Rapid and label-free detection of Brucella melitensis in milk and milk products using an aptasensor. Talanta, 200 (March), 263–271. https://doi.org/10.1016/j.talanta; 2019.03.048.
4. Bhankole A. Brucellosis risk assessment. 29–31; 2013.
5. Bodenham RF, Lukambagire AS, Ashford RT, Buza JJ, Rubach MP, Sakasaka P,Shirima GM, Swai ES. Prevalence and speciation of brucellosis in febrile patients from a pastoralist community of Tanzania.Scientific Reports, 1–11. https://doi.org/10.1038/s41598-020-62849-4; 2020.
6. Chota AC, Magwisha HB, Stella B, Bunuma EK, Shirima GM, Mugambi JM, Omwenga SG, Wesonga HO, Mbatha P, Gathogo S, Complex V, Muguga C. Prevalence of Brucellosis in livestock and incidences in humans in East Africa. African Crop Science Journal, 24(Supplement s1), 45–52. https://doi.org/http://dx.doi.org/10.4314/acsj.v24i1.5S; 2016.
7. Corbel M. et al. Brucellosis in humans and animals. World Health Organisation 2006 All, 89. https://doi.org/10.2105/AJPH.30.3.299; 2006.
8. Dadar M, Fakhri Y, Shahali Y, Mousavi Khaneghah A. Contamination of milk anddairy products by Brucella species: A global systematic review and meta-analysis. Food Research International, 128, 108775. https://doi.org/10.1016/j.foodres.2019.108775; 2020
9. .Dadar M, Shahali Y, Whatmore AM. Human brucellosis caused by raw dairy products: A review on the occurrence, major risk factors and prevention. International Journal of Food Microbiology, 292 (November 2018), 39–47.https://doi.org/10.1016/j.ijfood micro.2018.12.009; 2019.
10. Davies G, Casey A. The survival of Brucella abortus in milk and milk products. The British Veterinary Journal, 129(4), 345–353. https://doi.org/10.1016/S0007-1935(17)36436-9; 1973.
11. De Figueiredo P, Ficht TA, Rice-Ficht, A, Rossetti CA, Adams LG. Pathogenesis and immunobiology of brucellosis: Review of Brucella-host interactions. American Journal of Pathology, 185(6), 1505–1517. https://doi.org/10. 1016/j.ajpath.2015.03.003; 2015.
12. Dereje T, Benti D, Feyisa B, Abiy G. Review of common causes of abortion in dairy cattle in Ethiopia. Journal of Veterinary Medicine and Animal Health, 10(1), 1–13. https://doi.org/10.5897/jvmah2017.0639; 2018.
13. Ducrotoy M, Bertu WJ, Matope G, Cadmus S, Conde-Álvarez R, Gusi AM, Welburn S, Ocholi R, Blasco JM, Moriyón I. Brucellosis in Sub-Saharan Africa: Current challenges for management, diagnosis and control. Acta Tropica, 165, 179–193. https://doi.org/10.1016/j.actatropica.2015.10.023; 2017.
14. El-wahab EWA, Hegazy Y, El-tras WF, Mikheal A, Kabapy AF. A multiple risk model for brucellosis at the human-animal interface in Egypt. https://doi.org/10.1111/tbed.13295; 2020.
15. Franc KA, Krecek RC, Häsler BN. Brucellosis remains a neglected disease in the developing world : a call for interdisciplinary action. 1–9. https://doi.org/10.1186/s12889-017-5016-y; 2018.
16. Galińska EM, Zagórski J, Em G, Brucellosis ZJ. 233-238 in Humans-Etiology, Diagnostics, Clinical Forms. Annals of Agricultural and Environmental Medicine, 20(2), 233–238. www.aaem.pl; 2013.
17. Gibney MJ, Burstyn PG. Milk, serum cholesterol, and the Maasai. A hypothesis. Atherosclerosis, 35(3), 339–343.https://doi.org/10.1016 /0021-9150(80)90131-8; 1980.
18. Gidel R, Albert JP, Le Mao G, Retif M. [Epidemiology of human and animal brucellosis in western Africa. The results of six studies in the Ivory Coast, Upper Volta, and Nigeria]. Developments in biological standardisation, 31, 187–200; 1976.
19. Grützke J, Gwida M, Deneke C, Brendebach H, Projahn M, Schattschneider A, Hofreuter D, El-Ashker M, Malorny B, Al Dahouk S. Direct identification and molecular characterization of zoonotic hazards in raw milk by metagenomics using brucella as a model pathogen. Microbial Genomics. https://doi.org/ 10.1099/MGEN.0.000552; 2021.
20. Hanuš O, Kučera J, Samková E, Němečková I, Čítek J, Kopec, T, Falta D, Nejeschlebová H, Rysová L, Klimešová M, Elich O. Raw cow milk protein stability under natural and technological conditions of environment by analysis of variance. Foods, 10(9). https://doi.org/10.3390/foods10092017; 2021.
21. Jansen W, Demars A, Nicaise C, Godfroid J, de Bolle X, Reboul A, Al Dahouk S. Shedding of Brucella melitensis happens through milk macrophages in the murine model of infection. Scientific Reports, 10(1), 1–10. https: //doi.org/10.1038/s41598-020-65760-0; 2020.
22. John K, Fitzpatrick J, French N, Kazwala, R, Kambarage D, Mfinanga GS, MacMillan A, Cleaveland S. Quantifying risk factors for human brucellosis in Rural Northern Tanzania. PLoS ONE, 5(4). https://doi.org/10.1371/journal.pone.0009968; 2010.
23. Kaden R, Ferrari S, Jinnerot T, Lindberg M, Wahab T, Lavander M. Brucella abortus: Determination of survival times and evaluation of methods for detection in several matrices. BMC Infectious Diseases, 18(1), 1–6. https://doi.org/10.1186/s12879-018-3134-5; 2018.
24. Kai TMK, Aotearoa A. Microbiological Risk Assessment of Raw Cow Milk. Fsanz, December; 2009.
25. Karimuribo ED, Ngowi HA, Swai ES, Kambarage DM. Prevalence of brucellosis in crossbred and indigenous cattle in Tanzania. Livestock Research for Rural Development; 2007.
26. Kouamé-Sina SM, Makita K, Costard S, Grace D, Dadié A, Dje M, Bonfoh B. Hazard identification and exposure assessment for bacterial risk assessment of informally marketed milk in Abidjan, Côte d’Ivoire. Food and Nutrition Bulletin, 33(4), 223–234. https://doi.org/10.1177/156482651203300402; 2012.
27. Kunda J, Fitzpatrick J, Kazwala R, French NP, Shirima G, MacMillan A, Kambarage D, Bronsvoort M, Cleaveland S. Health-seeking behaviour of human brucellosis cases in rural Tanzania. BMC Public Health, 7. https://doi.org/10.1186/1471-2458-7-315; 2007.
28. Levira F, Todd G. Urban Health in Tanzania: Questioning the Urban Advantage. Journal of Urban Health, 94(3), 437–449. https://doi.org/10.1007/s11524-017-0137-2; 2017.
29. Manyori CI, Mumba C, Muma JB, Mwale MM, Munyeme M, Bwanga EK, Häsler B, Rich KM, Skjerve E. Quantitative risk assessment of developing salmonellosis through consumption of beef in Lusaka Province, Zambia. Food Control. https://doi.org/10.1016/j.food cont.2016.10.027; 2017.
30. Massis F De, Zilli K, Di G, Id D, Nuvoloni R, Pelini S, Sacchini L, Alterio ND, Giannatale E Di. Distribution of Brucella field strains isolated from livestock , wildlife populations , and humans in Italy from 2007 to 2015. 1–16; 2019.
31. Mathew C, Stokstad M, Johansen TB, Klevar S, Mdegela RH, Mwamengele G, Michel P, Escobar L, Fretin D, Godfroid J. First isolation , identification, phenotypic and genotypic characterisation of Brucella abortus biovar 3 from dairy cattle in Tanzania. BMC Veterinary Research, 1–9.https://doi.org/10.1186/s12917-015 -0476-8; 2015.
32. Melubo K. Why are wildlife on the Maasai doorsteps ? Insights from the Maasai of Tanzania. https://doi.org/10.1177/1177180120947823; 2020.
33. Méndez-González KY, Hernández-Castro R, Carrillo-Casas EM, Monroy JF, López-Merino A, Suárez-Güemes F. Brucella melitensis survival during manufacture of ripened goat cheese at two temperatures. Foodborne Pathogens and Disease, 8(12), 1257–1261. https://doi.org/10.1089/fpd.2011.0887; 2011.
34. Muma JB, Samui KL, Oloya J. Risk factors for brucellosis in indigenous cattle reared in livestock – wildlife interface areas of Zambia. 80, 306–317. https://doi.org/10.1016/j.prevetmed.2007.03.003; 2007.
35. Musallam I, Prisca A, Yempabou D, Ngong CC, et al. Acta Tropica Brucellosis in dairy herds : A public health concern in the milk supply chains of West and Central Africa. Acta Tropica, 197(May),105042.https://doi.org/10.1016/j.actatropica. 2019.105042; 2019.
36. Muturi M, Bitek A, Mwatondo A, Osoro E, et al. Risk factors for human brucellosis among a pastoralist community in South - West. BMC Research Notes, 1–6. https://doi.org/10.1186/s13104-018-3961-x; 2018.
37. Njarui D, Gatheru M, Wambua J, Hospital LC, Nguluu S. Consumption Patterns and Preference of Milk and Milk Products among Rural and Urban Consumers in Semi-Arid Kenya This article was downloaded by : On : 31 May 2011 Access details : Access Details : Free Access Publisher Routledge Ecology of Food and Nutrit. June 2016. https://doi.org/10.1080/03670244.2011.568908; 2011.
38. Pappas G, Papadimitriou P, Akritidis N, Christou L, Tsianos EV. The new global map of human brucellosis. 6(February), 91–99; 2006.
39. Spink W. Family studies on Brucellosis. 127–140; 1954.
40. Teske SS, Huang Y, Tamrakar SB, Bartrand TA, Weir MH, Haas CN. Animal and Human Dose-Response Models for Brucella Species. Risk Analysis. https://doi.org/10.1111/j.1539-6924.2011.01602.x; 2011.
41. Wainaina M, Aboge GO, Omwenga I, Ngaywa C, Ngwili N, Kiara H, Wamwere-Njoroge G, Bett B. Detection of Brucella spp. in raw milk from various livestock species raised under pastoral production systems in Isiolo and Marsabit Counties, northern Kenya. Tropical Animal Health and Production, 52(6), 3537–3544. https://doi.org/10.1007/s11250-020-02389-1; 2020
Published
2023-02-28
How to Cite
1.
Ndaki E, Muma J, M’kandawire E, Musawa G, Mukuma M, Karimuribo E, Banda M, Benhard V, Munyeme M, Mumba C. A Quantitative Risk Assessment of Human Exposure to Brucellosis Through the Consumption of Contaminated Raw Cow Milk in Arusha, Tanzania. Journal of Agricultural and Biomedical Sciences [Internet]. 28Feb.2023 [cited 26Aug.2025];6(2). Available from: https://journals.unza.zm/index.php/JABS/article/view/915
Section
Veterinary Medicine
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