Technical Considerations of Cholera Vaccines and Some Results of Cholera- El Tor Mass Immunization
نویسنده
چکیده
Among the bacterial vaccines used for prophylactic measures, Cholera vaccme does not give a complete protection or a satisfactory mass vaccinations result compared with other biologics used for the prevention of other human infectious diseases. This relative failure is partly due to the fact that cholera used to be, for many centuries, a problem in a limited part of Asia and from this asian focus it used to spread to other countries. In other words, cholera has never been a serious disease in those countries where it could be studied by all means and sorne specially potent vaccines could be developped. The lack of a potent cholera vaccine may also be attributed to the complex antigens inside the vibrio cens. Therefore we can not show among the existing cholera vaccines one which could be accepted as an ideal prophylactic. It is also shown that repeated injections of cholera vaccine wilI not always increase the level of immunity. On the other hand natural infe;;tion is followed by a resistance which usually fades after 6 months and one may be reinfected during subsequent outbreaks of cholera. The serological reactions are by no means paraIlel to the development of immunit y and on many occasions while there is a complete protection against cholera the serum antibody level remains negative. The ab ove mentioned remarks illustrate the difficuIties we face when inducing cholera immunity on a nation wide basis.
منابع مشابه
Technical considerations of cholera vaccines and some results of cholera - El-Tor mass immunization
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