Enterovirus 71 isolated from cases of epidemic poliomyelitis-like disease in Bulgaria

Abstract

Virological and serological studies of an epidemic disease in Bulgaria, 1975, were carried out. Epidemiologically, clinically and pathomorphologically, the disease simulated almost all known forms of poliomyelitis, acute stem encephalitis, encephalomyocarditis and aseptic meningitis. The studies completely rules out the participation of polioviruses and provided comprehensive evidence for the etiological role of a peculiar enterovirus subsequently identified as enterovirus (EV) type 71 known in the literature since 1974. Altogether, in 1975 and 1976 from 65 cases of poliomyelitis-like disease (PLD) 92 strains of EV71 were isolated, including 37 strains from the brain and medulla, 1 from the cerebrospinal fluid, 10 from mesenterial lymph nodes and tonsils and 44 from faeces. In addition, in 282 convalescent cases of the disease, diagnostic seroconversion or high titers of antibody to this virus were demonstrated. The most successful virus isolation was achieved by inoculation of green monkey kidney cell cultures and newborn white mice. Bulgarian strains of enterovirus 71 regularly caused paralysis in monkeys and morphological poliomyelitis-like lesions in their CNS, and paralysis and myositis with Zenker necrosis in newborn white mice, cotton rats, Syrian hamsters, and 3-week-old cotton rats. The diseased rodents had much more virus in their mucles than in brains.

Acute Encephalomyelitis during an Outbreak of Enterovirus Type 71 Infection in Taiwan: Report of an Autopsy Case with Pathologic, Immunofluorescence, and Molecular Studies

“…The topographic distribution of EV 71 infection in CNS is localized to brain stem, basal ganglia and spinal cord (3,6,7,9). Our findings were comparable with those described in previous reports: de- spite widespread inflammation in CNS, the gray matter of spinal cord and brain stem was most severely involved, the areas from which EV 71 was isolated.…”

“…Eight sets of primers were used for amplification and sequencing of the entire genome of the viral DNA. They were designed from published sequence data of EV 71 BrCr strain: primer pair I, 5Ј-TTAAAA-CAGCTGTGGGTTG [nucleotide (nt) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] as the sense strand primer, 5Ј-GAACTTCCAGTACCACCCC (nt 1196 -1178) as the antisense strand primer; primer pair II, 5Ј-TATGGTGAGTGGCCTTCATACTG (nt 1053-75) as the sense strand primer, 5Ј-AGTGAGTGTTAC-TGATCCATGGT (nt 2241-2218) as the antisense strand primer; primer pair III, 5Ј-TACACACCACCAG-GAGGCCCCT (nt 2115-2126) as the sense strand primer, 5Ј-ACCAGCATAATTTGGGTTGGCT (nt 3282-3261) as the antisense strand primer; primer pair IV, 5Ј-TTCCATTCATGT -CACCTGCGA (nt 2964 -2984) as the sense strand primer, 5Ј-GAAATGGGCGAG -GTATGACACA (nt 4291-4269) as the antisense strand primer; primer pair V, 5ЈATTAGTAAGTTTATT-TATTGGCT(nt 4149 -4171) as the sense strand primer, 5Ј-ACAACTGCAACCACAGTTGCTAT(nt 5271-5249) as the antisense strand primer; primer pair VI, 5Ј-TCCATTGCTACTGTGGTAGCAGT (nt 5253-5275) as the sense strand primer, 5Ј-TAGCAGGCTTCTTCC-ATTCTCAT (nt 6241-6219) as the antisense strand primer; primer pair VII, 5Ј-ACTAAGCTGGAA-CCCAGTG (nt 6003-6021) as the sense strand primer, 5Ј-ATAACAAATTTACCCCCACC (nt 7396 -7377) as the antisense strand primer; primer pair VIII, 5Ј-GAGAAATTTGTGAGTACAA (nt 7227-7245) as the sense strand primer, 5Ј-AGCAGTGGTAACAACGC-AGAG-TACT(30)CN (nt 7408 -7342). RT-PCR was carried out by RT-PCR beads (Pharmacia Biotech, Sweden).…”

“…The fatality rate among children was 93%. Autopsy examination showed brain stem encephalitis in the majority of cases (7). However, pulmonary edema or hemorrhage was not reported in Bulgarian epidemic.…”

“…The disease is usually self-limited without neurological deficits (6), whereas in HFMD associated with EV 71, serious and lethal complications may develop. There were two such outbreaks of EV 71 with rapid deterioration to death in young children previously (3,7). One was in Bulgaria in 1975 and the other was in Malaysia in 1997.…”

Cellular kinase inhibitors that suppress enterovirus replication have a conserved target in viral protein 3A similar to that of enviroxime

“…In infection by poliovirus (PV), which is the causative agent of poliomyelitis and belongs to the species Human enterovirus C, motor neurons are the major target for neurovirulence (Bodian, 1949). Enterovirus 71 (EV71), another neurotropic enterovirus belonging to the species Human enterovirus A, is a causative agent of hand, foot and mouth disease and herpangina, but sometimes causes severe neurological diseases, such as brainstem encephalitis and poliomyelitis-like paralysis (Chumakov et al, 1979;McMinn, 2002;Wang et al, 2003). EV71 causes fatal pulmonary oedema and pulmonary haemorrhage in young children by destruction of the vasomotor and respiratory centres in the brainstem Ho et al, 1999;Huang et al, 1999;Komatsu et al, 1999;Lum et al, 1998;Wang et al, 1999).…”