Type 3 poliovirus/Finland/1984 is genetically related to common Mediterranean strains

Insidious reintroduction of wild poliovirus into Israel, 2013

“…The major difference between the 1988 outbreak in Israel and other outbreaks of wild poliovirus infection in recent years in other developed countries [19,20] that used an IPV-only routine vaccination schedule, is the early detection of silent virus circulation through an existing early warning system, involving national environmental Notably, the highly probable chain of events that lead to the re-introduction of WPV1 into Israel in 2013 is not the first of its kind. Other possible long-distance point importations into decades-long polio-free countries were identified, in Finland and the Netherlands, following the paralytic polio outbreaks of 1986 and 1992, respectively [19][20][21][22]. This is in contrast to the endemic, Middle-Eastern origin of the 1988 outbreak due to WPV1 in Israel [1,3,4].…”

Geographical genotypes (geotypes) of poliovirus case isolates from the former Soviet Union: relatedness to other known poliovirus genotypes

“…Synthetic oligodeoxynucleotides were prepared, purified and analysed as described by Yang et al (1991). The following previously described primers were used: (i) the polio/2A primer (corresponding to positions 3508-3527) for RNA sequencing (Rico-Hesse et al, 1987); (ii) the PCR primer pair, EV/PCR1 (539-565) and EV/PCR2 (452~476), matching highly conserved sites within the 5'-noncoding regions of enterovirus genomes (da Silva et al, 1991); (iii) Fig. 1.…”

“…The 1991 Moldovan isolate was a representative of a third branch (T3) within the T geotype cluster, differing from the T1 isolates by 13 16 % (20-24 differences) and the T2 isolates by 12-13% (18-19 differences). Overall, the T geotype is quite heterogeneous, with some pairwise differences (T3/T1) exceeding 15%, the defined upper limit for divergence within a geotype (Rico-Hesse et al, 1987).…”

“…Indigenous strains isolated in different geographical regions usually exhibit a significant genetic diversity (Rico-Hesse et al, 1987;Kew et al, 1990a, b). On the other hand, a high degree of similarity has been observed among strains isolated during a given epidemic (Nottay et al, 1981; Lipskaya et al, 1985;Magrath et al, 1986;Kinnunen et al, 1991), and the viral genomes endemic to a territory tend to preserve some common features for years (Rico-Hesse et al, 1987;Kew et al, 1990a). These observations led to the concept of geographical genotypes of poliovirus (Rico-Hesse et al, 1987;Kew et al, 1990bKew et al, , 1993; for the sake of brevity and to avoid possible confusion, we shall designate the geographical genotypes as geotypes.…”

“…Depending on specific aims, viral RNA segments with various levels of conservation may be sequenced for the geotyping of wild-type polioviruses. In particular, it was found convenient to investigate just the junction between the structural and nonstructural regions of the genome, which encompasses a 3' portion of the gene for the capsid protein VP1 and a 5' portion of the nonstructural gene 2A (directing the synthesis of a multifunctional protein with a protease activity) (Rico-Hesse et al, 1987;Pryry et al, 1990); a limit of 15% divergence within this 150-nucleotide-long segment was set for strains belonging to the same geotype (Rico-Hesse et al, 1987). Sequencing of even limited regions of the wild-type poliovirus RNA has obvious epidemiological implications; the characterization of the geotype-specific RNA segments is also important for understanding certain regularities of poliovirus evolution (Rico-Hesse et al, 1987;Kew et al, 1990a, b).…”