Contamination Levels and Identification of Bacteria in Milk Sampled from Three Regions of Tanzania: Evidence from Literature and Laboratory Analyses

Table 1

Nutritional risks identified in milk sampled in different places of Tanzania and reported in literature.

Zone or region	Form of milk samples		Risk and levels (TBC or TCC in cfu/ml)	Risks in consumers	Reference
Southern highlands; (Iringa and Mbeya regions)	Fresh udder milk	805	M. tuberculosis (, 6.5%); Atypical Mycobacteria and Mycobacterium spp.(, 93.5%)	(1) TB; (2) Atypical Mycobacteria and Mycobacterium potentially pathogenic in low immunity people	[8]
East; (Coast and Morogoro)	Fresh udder milk	919	S. agalactiae (1.2%),; A. pyogenes (0.2%),; S. epidermidis (2.8%),; S. hyicus (0.1%),; S. intermedius (1.1%),; S. saprophyticus (0.3%),; S. aureus (1.7%),; Micrococcus spp. (0.7%),; Mucor spp. (2.4%),; Aspergillus spp. (0.1%),; Yeast (18.5%)	(1) Pathogen shed in milk due to udder infection; (2) Potential fungal infection	[9]
Dar es Salaam and Mwanza	Fresh from containers	982	Antimicrobial residues; (, 36%)	Exposure to unacceptable concentrations of antimicrobial; residues (above maximum residue limits)	[6]
Dar es Salaam	Fresh from containers	128	TBC; E. coli (6.3%),; Bacillus cereus (6.3%),; S. aureus (6.3%),; S. agalactiae (6.3%),; Enterobacter aerogenes (5.6%),; Enterococcus faecalis (4.7%)	(1) High bacterial count; (2) Pathogen shed in milk	[10]
Northern Coast (Tanga region)	Fresh from containers	59	TCC (up to ); B. abortus (, 56%); Adulteration	(1) Quality loss; (2) Brucellosis; (3) Quality loss	[11]
Eastern Coast (Dar es Salaam)	Fresh milk from containers	120	TBC (up to ); E. coli (83%); S. aureus (27.3%)	(1) High bacteria; (2) Lowered quality; (3) Contamination	[12]
Eastern Coast; (Dar es Salaam)	Boiled milk from containers	22	TBC (up to ); E. coli (36.4%); S. aureus (22.7%)	(1) Boiled with reduced bacteria but still pathogenic	[12]
Northern Coast; (Arusha region)	Fresh milk from sellers	75	Salmonella (, 37%)	Gastroenteritis	[13]
Northern Coast (Arusha region)	Fresh milk from containers	180	TBC (up to ); S. aureus (, 33%); Corynebacteriumspp. (, 11%); Pseudomonas spp. (, 10%)	(1) High bacteria, lowered nutritional quality; (2) Food poisoning	[14]
Eastern Coast (Morogoro region)	Fresh and boiled milk from containers	201	TBC (up to ); Adulteration; Antimicrobial residues (12.5–35.3%)	(1) High bacteria, lowered nutritional quality; (2) Adulteration causes lowered nutritional quality and contamination; (3) Exposure to unacceptable concentrations of antimicrobial residues	[15]

: sample size in literature from which data were extracted; TBC: total bacterial count; TCC: total coliform count; (): identified risk level – number of positive samples () or percentage (%).