Reversion of the attenuated and temperature-sensitive phenotypes of the Sabin type 3 strain of poliovirus in vaccinees.
Isolates of type 3 poliovirus from vaccine-recipients were characterized in terms of virulence, sensitivity of growth to high temperatures, and differences in genome structure from the Sabin type 3 vaccine strain. These included point mutations in the region of the genome coding for the structural proteins and in the 5' noncoding region, and the presence of type 1 or type 2 poliovirus genomic sequences resulting from intertypic recombination. Isolates from healthy vaccinees resembled those from vaccine-associated cases of poliomyelitis in all of these properties. Suppression of the temperature-sensitive phenotype was strictly correlated with reversion to virulence in nonrecombinant type 3 strains. Recombinant isolates were more attenuated than expected, even when they had lost all mutations known to attenuate the type 3 vaccine strain.
Macadam
A J
AJ
National Institute for Biological Standards and Control, Potters Bar, Herts, United Kingdom.
Arnold
C
C
Howlett
J
J
John
A
A
Marsden
S
S
Taffs
F
F
Reeve
P
P
Hamada
N
N
Wareham
K
K
Almond
J
J
D001483:Base Sequence; D002460:Cell Line; D003434:Crossing Over, Genetic; D005814:Genes, Viral; D006801:Humans; D009154:Mutation; D010641:Phenotype; D011051:Poliomyelitis / Q000382:microbiology*; D017955:Poliovirus / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D011055:Poliovirus Vaccine, Oral; D012367:RNA, Viral / Q000235:genetics*; D013696:Temperature; D014764:Viral Proteins / Q000235:genetics; D014774:Virulence
D011055:Poliovirus Vaccine, Oral; D012367:RNA, Viral; D014764:Viral Proteins