Mm. Elsageyer et al., CHARACTERIZATION OF AN ECHOVIRUS TYPE-11' (PRIME) EPIDEMIC STRAIN CAUSING HEMORRHAGIC SYNDROME IN NEWBORN BABIES IN HUNGARY, Acta virologica (Anglicka verze), 42(3), 1998, pp. 157-166
Echovirus 11' (prime) isolates from an epidemic of haemorrhagic syndro
me in departments of obstetrics in Hungary have been characterised. Th
e leading component of the clinical disease was carditis and its letha
l outcome occurred in 13 newborn babies. Maternal immunity was found t
o be absent even in women of 41 years of age. The application of monov
alent oral poliovirus type I vaccine prevented the progress of the epi
demic within two weeks. Nevertheless, a serological survey among primo
vacinees of 3-15 months of age revealed that 20% of the babies serocon
verted without clinical symptoms during the epidemic. Serological evid
ence showed that the echovirus 11' infection was unable to interfere w
ith the efficacy of oral poliovirus vaccine (OPV), since seroconversio
n rates of primovaccinees did not differ significantly from those in t
he group seroconverted also to echovirus 11' during the vaccination ca
mpaign. A 440 nucleotide (nt) fragment of the 5'-non-translated region
of 12 epidemic echovirus 11' isolates and 26 echovirus prototype stra
ins was amplified by a nested reverse transcription-polymerase chain r
eaction (RT-PCR) and analysed using three different restriction endonu
cleases. The 5'-regions of the echovirus 11' isolates were found to be
identical to each other but different from that of the prototype echo
virus 11 (Gregory) strain. The results indicate that echovirus 11' iso
lates underwent genetic changes in the 5'-end and P1 region of the gen
ome before the onset of the epidemic.