Table 1.

Examples of estimated usage of SV40-contaminated oral poliovaccines^a,^b

Country	Source of OPVc	Date of usage	Estimated no. of vaccinees
Belgian Congo	CHAT	1958	240,000
Colombia	Lederle	1958–1959	140,000
Costa Rica	Lederle	1959–1960	272,000
Croatia	CHAT	1960	1.3 million
Czechoslovakia	Sabin	1958–1959	143,000
Egyptd	Russian	NAd	NA
Hungary	Russian	1960–1978 (est.)	2.5 million (1960)
Japan	Russian	1961–1963	~15 million
Mexico	Sabin	1958–1959	308,000
Nicaragua	Lederle	1958–1959	42,000
Poland	CHAT	1959	9 million
Uruguay	Lederle	1958–1959	218,000
USA, Cincinnati	Sabin	1960	181,000
USA, Miami	Lederle	1959	410,000
USSR	Russian	1959–1978 (est.)	Many millions

^aSee Butel [23,34] for original references. The list is not comprehensive.

^bMainly children were vaccinated.

^cOPV, oral poliovaccine; CHAT, Koprowski candidate vaccine that was based on the same poliovirus strains as Lederle Laboratories’ candidate vaccine; Russian OPV was based on Sabin vaccine virus strains.

^dNA, not available. Parenteral antischistosomal therapy was provided in Egypt until the 1980s.