; "> Development of environmental, safe and protective vaccines against infectious pathogens
remains a challenge. In consequence of its high morbidity and mortality rates canine
distemper is one of the most important diseases of young dogs. The object of the present
study is to develop a selected method for preparation of an inactivated canine distemper
vaccine. This method involved exposure of the virus to different concentrations of binary
ethyleneimine (BEI), beta propiolactone (ßPL) and hydrogen peroxide (H2O2). Complete virus
inactivation was obtained with BEI (0.003M) for 6 hours, ßPL (1/5000) for 4 hours and H2O2
at a concentration of 3% rapidly inactivated a Vero cell adapted canine distemper virus strain
within 3 h of exposure without affecting its antigenicity or immunogenicity. The safety,
immunogenicity and potency induced in four groups of puppies were evaluated using the
three prepared experimental batches of inactivated canine distemper vaccine. These results
revealed that no residual infectious virus was detected in H2O2 inactivated CD vaccine that
proved to be safe and effective when compared with the same virus harvest that inactivated
with the classical inactivating agents as BEI and βPL. Thus, an alternative inactivation
method, such as H2O2 is able to maintain the integrity of the virus protein may be essential
for improving the potency of inactivated canine distemper virus vaccine produced sufficient
level of antibodies which measured by serum neutralization test (SNT) and was protected
when challenged with virulent CD virus strain. These findings reinforce the idea that H2O2
can replace BEI and βPL as inactivating agents for canine distemper virus to reduce time and
cost of inactivation process.