[An outbreak of poliomyelitis in Tajikistan in 1991 caused by the poliomyelitis virus type 1 in concomitant echovirus 19 infection].

In 1991 in Tajikistan 36 cases of acute poliomyelitis were recorded (spinal form 27, bulbospinal 3, pontospinal 6 cases) in children ranging in ages from 6 months to 6 years. The outcome of the disease was fatal in 4 cases and with crude residual effects in 32 children. Out of 23 children examined, poliomyelitis virus type I was isolated from 13, antibodies to poliovirus type I in titres 1:16 to 1:1024 were detected in 21 children, ECHO 19 virus was isolated from 5 children and antibodies to this virus in titres 1:16 to 1:8192 were demonstrated in 13 children. The fresh isolates of poliomyelitis virus type I had rct+, DS+ and N+ markers. The strains of ECHO 19 virus were highly pathogenic for monkeys causing deaths of the animals within 3-4 days. It is assumed that the main causative agent of the Tajikistan outbreak of poliomyelitis was a virulent "wild" variant of poliovirus type I. The preceding or concomitant infection with ECHO 19 virus (considering the data from the literature and the demonstrated high virulence of this agent for monkeys) could exert an aggravating effect on the course of poliomyelitis or, in some cases, be an independent cause of the disease and, possibly, death of the children.