Raw Milk as a Vehicle of Brucella Infection for Human in Behera Province

Brucellosis is a worldwide zoonosis that has major public health
concern in Egypt. The present work was conducted to investigate the
seroprevalence of brucellosis in milk as well as in serum samples of
humans on basis of the Milk Ring Test (MRT) and Rose Bengal plate test
(RBPT), respectively and further confirmation by polymerase chain
reaction (PCR). A total of 240 raw milk samples (98 from dairy markets,
128 samples from farm with history of mastitis and 14 samples from
retailers) were collected during the period extended from November, 2017
to October, 2018 beside another 100 serum samples were collected from
patients attending fever hospitals (60), individuals with occupational
contact with investigated animals (20) and apparently healthy individuals
attending private laboratories in Behera seeking for medical advice (20). It
was found that the overall prevalence of brucellosis in milk was 10.8% by
MRT. Also, it was observed that sero-prevalence of Brucella Abs in milk
samples in relation to sources of milk revealed that the highest rate was
recorded in milk samples collected from retailers (14.3%) followed by
those collected from dairy farms (12.5%) then those of dairy markets
(8.2%) with non-significant association between the rates of detection.
Concerning season, there was highly significant relationship between
season and percent of infection with Brucella, the high percent of infection
found in winter season (15.4%) than in summer season (6.5%). On the
other side, the seroprevalence of Brucella Abs in human serum samples by
RBPT clarified that the highest detection rate occurred in individuals with
occupational contact (25%) followed by patients with fever complain
(18.3%) and finally apparently healthy individuals (10%) with significant
association between them. Seasonal prevalence in human samples clarified
higher summer prevalence (20.5%) compared to winter (16.4%).
Moreover, there was significant relationship between age and infection rate
in human (P<0.05), with higher percentage of infection recorded in age
group over than 40 years by 23.3% (10/43) followed by age group (15-40
years) (16.7%) (6/36) and lastly those less than 15 years (9.5%) (2/21).
From our result, it is concluded that MRT and RBPT used as screening
tests for detection the prevalence of species in milk and serum samples,
Brucella infection is found with high percent in milk in Behera Province
highlighting the hazardous role in milk in transmission of Brucella
infection to consumers specially those used to drink raw milk in rural
areas. In addition PCR is gold confirmatory technique for diagnosis of
brucellosis in both milk and blood. .