Seroprevalence of human Brucellosis and associated risk factors among high-risk occupations in Mbeya Region of Tanzania

Abstract

Background: Brucellosis is a bacterial zoonotic disease of public health and economic importance. A cross-sectional study was conducted in Mbeya region between November 2015 and January 2016 to investigate the seroprevalence of human brucellosis and identify associated risk factors among individuals in risky occupations.

Methods: A total of 425 humans from six occupational categories were serially tested for Brucella antibodies using the Rose Bengal Plate Test (RBPT) and competitive Enzyme Linked Immunosorbent Assay (c-ELISA), for screening and confirmation, respectively. A questionnaire survey was also administered to participants to collect epidemiological data.

Results: The overall seroprevalence among the occupationally exposed individuals was 1.41% (95% CI: 00.64-3.12). Seroprevalence was higher among butcher men 5.6% (95% CI: 1.68-5.26), herds men 1.35% (95% CI: 0.18-9.02); and abattoir workers 1.1% (95% CI: 0.26-4.22) although there was no statistical significance. (Pvalue =.18). Seroprevalence was also higher among men (1.8%) compared to females (0%) (Pvalue =.19). and also, among those aged < 11 years (2.5%). Individuals who consumed raw milk had a higher seroprevalence (1.56%) compared to those who drunk boiled milk while seropositivity was 0.88% among those who assisted animals during parturition (Pvalue =.49). Butcher men were at higher risk of exposure compared to other occupational categories. Our findings show the presence of brucellosis in occupationally exposed individuals in Mbeya region.

Conclusion: There is need to sensitize the concerned professions in order to reduce the risk of acquiring Brucella infections from animals and animal products This also calls for public health awareness about the disease, and implementation of measures to prevent further spread of brucellosis within and outside the study area.

Keywords

Brucellosis / Human / Occupation / Seroprevalence / Risk factors

References

[1] OIE. The Manual of Diagnostic Tests and Vaccines for Terres-trial Animals. 7th editio. 2012; 2: 819-1404. Available at: https://www.oie.int/doc/ged/D12009.PDF

[2] Scholz HC, Revilla-Fernández S, Dahouk SAl, et al. Brucella vulpis sp. Nov., isolated from mandibular lymph nodes of red foxes (vulpes vulpes). Int J Syst Evol Microbiol. 2016 May 1; 66( 5): 2090-8. PMid:26928956. https://doi.org/10.1099/ijsem.0.000998

[3] Seleem MN, Boyle SM, Sriranganathan N. Brucellosis: A re-emerging zoonosis. Vet Microbiol. 2010 Jan; 140(3-4): 392-8. PMid:19604656. https://doi.org/10.1016/j.vetmic.2009.06.021

[4] Lucero NE, Corazza R, Almuzara MN, et al. Human Brucella canis outbreak linked to infection in dogs. Epidemiol Infect. 2010 Feb; 138(2): 280-5. PMid:19653929. https://doi.org/10.1017/S0950268809990525

[5] Ducrotoy M, Bertu WJ, Matope G, et al. Brucellosis in Sub-Saharan Africa: Current challenges for management, diagnosis and con-trol. Acta Trop. 2017 (November); 165: 179-93. PMid:26551794. https://doi.org/10.1016/j.actatropica.2015.10.023

[6] Dean AS, Crump L, Greter H, et al. Clinical manifestations of human brucellosis: a systematic review and meta-analysis. PLoS Negl Trop Dis. 2012; 6(12): e1929.PMid:23236528. https://doi.org/10.1371/journal.pntd.0001929

[7] Yumuk Z, O’Callaghan D. Brucellosis in Turkey - an overview. Vol. 16, International Journal of Infectious Diseases. 2012. PMid:22333223. https://doi.org/10.1016/j.ijid.2011.12.011

[8] Godfroid J. Brucellosis in livestock and wildlife: Zoonotic diseases without pandemic potential in need of innovative one health ap-proaches. Arch Public Heal. 2017; 75(1): 1-6. PMid:28904791. https://doi.org/10.1186/s13690-017-0207-7

[9] Muma J, Samui I, Munyeme M, et al. Brucellosis in Rural Com-munities in Zambia and Factors Associated with Increased anti _ Brucellosis spp. antibody Presence Brucellosis in Rural Communi-ties in Zambia and Factors Associated. UNZA J Sci Technol. 2008; 12(June): 9-18.

[10] Awah-Ndukum J, Mouiche MM, Kouonmo-Ngnoyum L, et al. Seroprevalence and risk factors of brucellosis among slaughtered indigenous cattle, abattoir personnel and pregnant women in Ngaoundéré Cameroon. BMC Infectious Diseases. 2018 Dec 1; 18(1): 611. PMid:30509193. https://doi.org/10.1186/s12879-018-3522-x

[11] Amegashie EA, Owusu-Dabo E, Salifu SP, et al. Sero-prevalence and occupational risk factors for Brucella infection among slaughterhouse workers and butchers in Kumasi, Ghana. J Epidemiol Res. 2016 Sep 18; 3( 1). https://doi.org/10.5430/jer.v3n1p17

[12] Tsegay A, Tuli G, Kassa T, et al. Seroprevalence and risk factors of brucellosis in abattoir workers at Debre Zeit and Modjo export abattoir, Central Ethiopia. BMC Infect Dis. 2017 Dec 26; 17(1): 101. PMid:28125966. https://doi.org/10.1186/s12879-017-2208-0

[13] Igawe PB, Okolocha E, Kia GS, et al. Seroprevalence of brucel-losis and associated risk factors among abattoir workers in Bauchi State, Nigeria. Pan African Medical Journal. 2020 Feb 7; 35(33). https://doi.org/10.11604/pamj.2020.35.33.18134

[14] Nguna J, Dione M, Apamaku M, et al. Seroprevalence of brucellosis and risk factors associated with its seropositivity in cattle, goats and humans in Iganga District, Uganda. The Pan African Medical Journal. 2019; 33. PMid:31489077. https://doi.org/10.11604/pamj.2019.33.99.16960

[15] Tasiame W, Emikpe BO, Folitse RD, et al. The prevalence of bru-cellosis in cattle and their handlers in North Tongu District of Volta Region, Ghana. African journal of infectious diseases. 2016; 10(2): 111-7. PMid:28480445. https://doi.org/10.21010/ajid.v10i2.6

[16] John K, Fitzpatrick J, French N, et al. Quantifying risk factors for human brucellosis in Rural Northern Tanzania. PLoS One. 2010; 5(4). PMid:20376363. https://doi.org/10.1371/journal.pone.0009968

[17] Bouley AJ, Biggs HM, Stoddard RA, et al. Brucellosis among hos-pitalized febrile patients in northern Tanzania. Am J Trop Med Hyg. 2012 Dec; 87(6): 1105-11. PMid:23091197. https://doi.org/10.4269/ajtmh.2012.12-0327

[18] James LW. Studies on human brucellosis in the Mikumi selous ecosys-tem, Morogoro, Tanzania (MSc Thesis, Sokoine University of Agri-culture). Sokoine University of Agriculture. 2013.

[19] Assenga JA, Matemba LE, Muller SK, et al. Epidemiology of Bru-cella infection in the human, livestock and wildlife interface in the. BMC Vet Res. 2015; 1-11. PMid:26253151. https://doi.org/10.1186/s12917-015-0504-8

[20] Mngumi EB, Mirambo MM, Wilson S, et al. Predictors of specific anti-Brucella antibodies among humans in agro-pastoral communities in Sengerema district, Mwanza, Tanzania: the need for public aware-ness. Trop Med Health. 2016 Dec 18; 44(1): 34. PMid:27857610. https://doi.org/10.1186/s41182-016-0034-5

[21] Mirambo MM, Mgode GF, Malima ZO, et al. Seropositivity of Brucella spp. and Leptospira spp. antibodies among abattoir work-ers and meat vendors in the city of Mwanza, Tanzania: A call for one health approach control strategies. Foley J, editor. PLoS Negl Trop Dis. 2018 Jun 25; 12(6): e0006600. PMid:29939991. https://doi.org/10.1371/journal.pntd.0006600

[22] Carugati M, Biggs HM, Maze MJ, et al. Incidence of human brucel-losis in the Kilimanjaro Region of Tanzania in the periods 2007-2008 and 2012-2014. Trans R Soc Trop Med Hyg. 2018 Mar 1; 112(3): 136-43. PMid:29697848. https://doi.org/10.1093/trstmh/try033

[23] Swai ES, Schoonman L. Human Brucellosis: Seroprevalence and Risk Factors Related to High Risk Occupational Groups in Tanga Municipality, Tanzania. Zoonoses Public Health. 2009 May; 56(4): 183-7. PMid:18811674. https://doi.org/10.1111/j.1863-2378.2008.01175.x3

[24] Sagamiko FD, Muma JB, Karimuribo ED, et al. Sero-prevalence of Bovine Brucellosis and associated risk factors in Mbeya region, Southern highlands of Tanzania. 2017. Available from: https://ac.els-cdn.com/S0001706X17309312/1-s2.0-S0001706X17309312-main.pdf?_tid=6e2ff56d-b404-4b39-a53c-413f9394b45a&acdnat=1526644668_3ffc2cac6373cb01b05de5264d5f258e

[25] NBS. Tanzania National Bureau of Statistics - Tanzania in Figures. 2012. Available at: https://www.nbs.go.tz/index.php/en/tanzania-in-figures/274-tanzania-in-figures-2012

[26] Muma JB, Lund A, Nielsen K, et al. Effectiveness of Rose Bengal test and fluorescence polarization assay in the diagnosis of Brucella spp. infections in free range cattle reared in endemic areas in Zambia. Trop Anim Health Prod. 2009 Jun; 41(5): 723-9. PMid:18956247. https://doi.org/10.1007/s11250-008-9244-0

[27] Madut NA, Muwonge A, Nasinyama GW, et al. The sero-prevalence of brucellosis in cattle and their herders in Bahr el Ghazal region, South Sudan. PLOS Neglected Tropical Diseases. 2018; 12(6): e0006456. PMid:29924843. https://doi.org/10.1371/journal.pntd.0006456

[28] Esmaeili S, Naddaf SR, Pourhossein B, et al. Seroprevalence of brucellosis, leptospirosis, and Q fever among butchers and slaugh-terhouse workers in south-eastern Iran. PloS one. 2016; 11(1). PMid:26731333. https://doi.org/10.1371/journal.pone.0 144953

[29] Tumwine G, Matovu E, Kabasa JD, et al. Human brucellosis: sero-prevalence and associated risk factors in agro-pastoral communities of Kiboga District, Central Uganda. BMC Public Health. 2015 Dec; 15(1): 900. PMid:26374402. https://doi.org/10.1186/s12889-015-2242-z

[30] Njombe A, Msanga Y, Mbwambo N, et al. The Tanzania dairy indus-try: Status, opportunities and prospects. 2011 undefined.