Observations on the Use of Oral Poliovirus Vaccines in the Carribbean and Canada

Investigations on the use of poliovirus vaccines in the Caribbean and Canada are reviewed. Studies in Trinidad and Tobago in 1963 showed that children who were given two doses of oral poliovirus vaccine responded satisfactorily to the type 2 and type 3 components but poorly to the type 1 component. Studies on poliovirus vaccines in Canada have indicated that both killed and live vaccines are capable of controlling poliomyelitis. Results of studies undertaken in Ontario suggested that the response to a killed vaccine was not entirely satisfactory. The need for continued surveillance for poliomyelitis is emphasized. Action should be taken to review immunization procedures when a single case occurs. Consideration should be given to the use of monovalent vaccines in tropical countries. One of the major concerns to health authorities who have the responsibility for the control of poliomyelitis is the failure of oral vaccines to stimulate good antibody responses in children living in tropical countries. Of particular concern is the response to the type 1 component of the vaccine, since the majority of the outbreaks of poliomyelitis are due to the type 1 virus. In this brief presentation, I wish to draw attention to some investigations that were carried out on poliovirus vaccines in the Caribbean islands of Trinidad and Tobago and in Canada.