AN EPIDEMIC OF ASEPTIC MENINGITIS, PRIMARILY AMONG INFANTS, CAUSED BY ECHOVIRUS 11-PRIME

Abstract

In the summer of 1965 an epidemic of aseptic meningitis and other acute febrile illness occurred in New Haven, Connecticut. The agent responsible proved to be echovirus 11-prime, a distantly related variant of the prototype Gregory strain of echo-11, which has not heretofore been associated with a community outbreak. The age group attacked was unusual in that more than half the virus positive patients with meningitis were under 6 months old. Other syndromes encountered, chiefly in the 1 to 4 year age group, were nonspecific febrile illnesses and respiratory infections, including pneumonia. A serologic survey indicated that echovirus 11-prime had not been active in the area previously; but, several months following the outbreak more than half the children in the crowded central area of the city, where most of the cases had occurred, possessed antibody to the epidemic strain. The strain of echo-11 prime was unlike other echoviruses in that it grew well in continuous line HEp-2 cells and primary isolations could be made in this cell system. Postinfection antibody titers in patients were in general low; one patient whose spinal fluid had yielded virus had no detectable antibody against the epidemic strain 6 months after onset.