Experimental study of brucella vaccines in mice and guinea pigs, with special references to serological diagnosis of workers in field of vaccine production

Document Type : Original Article


1 Department of Zoonosis, Faculty of Veterinary Medicine, Benha University

2 Veterinary Serum and Vaccine Research Institute, Sera and Antigens Department, Abbasia, Cairo


In this study, groups of 150 brucella free white Swiss mice, were inoculated with different oily
adjuvanated brucella melitensis subunit vaccines alone or both and then were challenged with Br.
melitensis virulent strain for the evaluation of the immune response of each subunit vaccine which was
judged by testing this potency through spleen to body weight ratio and the number of brucellae per gram
spleen. Also two groups of brucella free guinea pigs were inoculated with a combination of different
oily adjuvanated Brucella melitensis subunit vaccines combined with either live attenuated Br. abortus
strain 19 vaccine, inoculated conjunctivally or RB51 vaccine injected subcutaneously. Then the animals
were challenged with virulent Br. melitensis strain. Humeral and cell mediated immune responses were
evaluated. The shedding of the vaccinal strains in the different body secretions was detected along the
whole days of the experiment. Eighteen serum samples were collected from occupational group working
in the vaccine production and application for serological examination. It was found that the protection
level in the different mice animals groups was 70%, while in the vaccinated guinea pigs vaccinated with
the combined oily adjuvanated Br. melitensis subunit vaccine combined with strain 19 vaccine, was
90%, while in those combined with RB51 vaccine, the protection level was 85%. In addition, no vaccinal
strains were detected in the different body secretions of the vaccinated animals along the whole days of
the experiments. Only two cases of the occupational group were positive.