Joseph A. Bell

Four newly recognized adenoviruses.

Summary A number of strains of adenoviruses recovered from anal swabs of children in Washington, D. C., were found to belong to the 4 previously unrecognized adenovirus serotypes (BP-1, BP-2, BP-4, BP-5) described in this report. The Adenovirus Committee of the Nat. Inst. of Allergy and Infectious Diseases has recommended that these viruses be designated adenovirus types 25, 26, 27, and 28 respectively. The authors are indebted to Mrs. J. Hovis, Mr. R. Low, Mr. H. Turner, and Mrs. M. Wormald for valuable technical assistance.

DEFINITION AND OUTLINE OF CONTEMPORARY INFORMATION ON THE ADENOVIRUS GROUP

This report reviews briefly the current knowledge of the adenoidal-pharyngeal-conjunctival (APC) viruses, recently renamed the adenovirus group,l with particular reference to their relation to human disease.2 The adenoviruses are defined as a group of serologically distinct viruses sharing the same soluble complement-fixing antigens and having the common properties of ether resistance, apathogenicity for laboratory animals, and characteristic cytopathogenicity for human and simian epithelium.3f4 Virus in culture fluids is 80 to 120 mp in diameter, whereas intracellular virus, which is found in the nuclei in “crystalline-like” patterns, measures 50 to 65 mp.6-7 All adenoviruses tested, with the exception of Type 4, are highly stable, withstanding room temperature for 3 weeks with no apparent decrease in infectivity. While adenoviruses have been propagated in a variety of tissues, HeLa cell cultures provide the most sensitive and practical tissue for virus isolation. Growth of these viruses in HeLa cells is accompanied by an acid reaction of the culture fluids, in contrast to the production of an alkaline reaction in monkey-kidney and human-embryonic cultures. An important laboratory characteristic is the marked effect of dilution on the incubation period of cytopathogenic effects; in HeLa cells, each half-log dilution of virus generally produces a 1-day prolongation of the incubation period. This effect has obvious implications on designing sensitive virus isolation and titration procedures. Both monkeykidney and HeLa cell cultures are suitable for neutralization tests, and the KB7* cell is the most satisfactory tissue for the production of high-titer virus and complement-f ixing antigens. Complement-fixing antibody responses to viruses of the adenovirus group are group-specific, while neutralizing antibody responses are generally type~pecific.~ s The broad, nontype-specific, complement-fixing antibody response of infected humans provides the most definitive method for including a virus in the adenovirus group. Inclusion of a virus in the group is based primarily on the demonstration that the virus, when used as antigen in the complementfixation test, will detect antibody rises in paired sera of humans infected with other adenovirus serotypes. Serotypes within the group are classified by reciprocal neutralization tests with rabbit antisera. The group is known to consist of at least 16 serotypes, of which 13 are isolated from human sources and 3 from simian sources.8 Adenoviruses have been isolated in North America, Western Europe, Russia, and Arabia. Complement-fixing antibodies to the adenovirus group antigen are prevalent not only in human sera, but also in chimpanzees, rhesus monkeys,

Primary isolation of influenza A, B, and C viruses in monkey kidney tissue cultures.

Summary 1. Influenza virus isolations were attempted simultaneously in monkey kidney tissue cultures and 11-day embryonated eggs from 78 throat samples taken during the 1955 epidemic in the Washington, D.C. area. Higher percentage of influenza B isolations was made in monkey kidney tissue cultures (21.8%) than in embryonated eggs (1.3%). Influenza C and Type 3 APC viruses were also recovered in the monkey kidney tissue cultures from some of these samples. Influenza A virus and influenza C virus were also isolated in monkey kidney cultures from other samples, but whether this method offers a better medium than the usual embryonated eggs was not determined for these types. 2. Cytopathogenic changes in monkey kidney cultures produced by influenza A, B, and C viruses appeared to be similar. These changes were readily recognized, and were associated with the production of hemagglutinins. 3. The use of monkey kidney cultures offered distinct advantages over chick embryos: (a) current strains of influenza B virus could be more readily isolated, (b) the time required for isolation and identification of the virus was shortened and (c) other respiratory tract viruses such as the Type 3 APC virus could be isolated.

Observations on some Little-Known Adenoviruses.

Summary The occurrence of a number of little-known adenovirus serotypes in children in an institution in Washington, D. C., is described. These viruses, which included types 9, 10, 12, 13, 16, 17, 24, 25, 26, 27, 28, BP-6, and BP-7 were isolated almost exclusively from anal specimens. As a group they were almost as common as the better known serotypes 1, 2, 3, and 5. It was shown that the latter types, although frequently present in routine throat specimens, were also more frequently isolated from routine anal specimens. Homotypic hemagglutination-inhibition antibody rises were demonstrated in children infected with most of the little-known serotypes.

Rubella: Frequency of antibody among children and adults and isolation of the virus from fetal tissues, a report from the Collaborative Study of Cerebral Palsy

We believe this study supplies data to support a multiple etiology concept of acute glomerulonephritis. Dr. Etteldorf inquired into the antibiotic history since these drugs have been shown to prevent a significant rise in the ASO titer. Only 2 children in each group received antibiotic therapy previous to hospitalization. The 2 children in the low ASO group did not receive penicillin but a tetracycline. Since antibiotics were used in only 2 out of 12 children, we feel that antibiotics could not be responsible for the low ASO titer. Dr. Burke was concerned with chronleity and asked for functional clearances to help differentiate acute from chronic nephritis. We did not do creatinine or inulin clearances but we did follow our patients with sedimentation rate and Addis count determinations. You will remember that most of our children in the low ASO group had recovered within three months, suggesting an acute process ra ther than a chronic process.