New Viruses Observed in Children with Respiratory Diseases

Abstract

EVENTUAL control of the common respiratory diseases depends on the determination of their etiology. Despite recent notable advances in delineating the viral etiology of such illnesses-at least 70 newly recognized viral agents have been described since 1948the causes of most remain to be found. The preliminary report outlined here presents data on two new respiratory viruses which have been found in children with respiratory illnesses and which, while biologically related to influenza and mumps, are also quite distinct. Previously unrecognized myxoviruses classified in two serologic groups were isolated from children with respiratory illnesses during October and November 1957 (1). These two new groups of agents, provisionally called hemadsorption (HA) viruses types 1 and 2, were isolated in monkey kidney cultures with the use of the hemadsorption technique recently introduced by Vogel and Shelokov (2, 3). Preliminary clinical and epidemiological observations indicated that these agents might be responsible for a proportion of the common acute respiratory illnesses in children which remain largely unexplained despite recent advances exemplified by the discovery of adenoviruses (4, 5) and other new agents (6-9). The type 1 HA virus was isolated from 35 children, 8 of whom were studied in Washington, D. C., hospitals and 27 of whom were involved in an outbreak of febrile respiratory illness in a nursery group of a District of Columbia welfare institution (Junior Village). When throat swabs were collected on one day from all infants in the affected nursery and tested for HA viruses, epidemiological analysis indicated that there was a significant association of type 1 HA virus isolations with febrile illnesses (chi-square test indicated P==0.03), thus strongly suggesting but not proving an etiological relationship. The illnesses were characterized by fever of 2 to 3 days' duration and cough. Nearly half of the cases had moist medium to fine rales; several had coarse breath sounds and rhonchi. Type 2 HA virus was isolated from three infants with acute laryngotracheobronchitis (croup), and more experience will be required with this agent before its etiological importance in disease can be determined. Acute and convalescent serum specimens from patients yielding either type 1 or type 2 virus showed substantial antibody rises in complement fixation and hemagglutination inhibition tests. Specimens from 82 hospitalized patients without respiratory illnesses did not yield the two viruses. The contribution of the HA viruses to the total respiratory disease picture cannot be assessed at this time. However, serologic data suggest that the contribution of these agents to childhood respiratory illnesses may be substantial. Preliminary surveys for antibodies against HA viruses in the serums of 55 adults, Dr. Chanock, Dr. Bell, Dr. Rowe, and Dr. Huebner are all with the Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, Public Health Service. Dr. Parrott is physician-inchief of Children's Hospital, Washington, D. C., with which Dr. Chanock is also associated.