Adenovirus Type 21 in a Civilian

Abstract

To the Editor:Our case report, “Diffuse Pneumonitis Due to Adenovirus Type 21 in a Civilian,” appeared in the July 1980 issue of Chest. Subsequent to the acceptance of the manuscript, Hierholzer et al1Hierholzer JC Torrence AE Wright PF Generalized viral illness caused by an intermediate strain of adenovirus (21/H21 + 35).J Infect Dis. 1980; 141: 281-288Crossref Scopus (18) Google Scholar described an intermediate strain of adenovirus (20/H21 + 35) which was identified as adenovirus 21 by serum-neutralization tests and as types 21 and 35 by hemagglutination-inhibition tests. Adenovirus 35 is a candidate adenovirus strain currently under review by the World Health Organization.The publication by Hierholzer et al prompted us to seek confirmation of the identity of our isolate in their laboratory. It now appears that our isolate more closely resembles adenovirus 35 than adenovirus 21, although it behaved atypically for an adenovirus 35 (ie, antiserum to adenovirus 21 reacted by serum–neutralization [titer ?101 and by hemagglutination–inhibition [titer 20–801). Type 35 was not suspected earlier because the published report detailing its reactions had shown only low level hemagglutination inhibition reactivity and no serum-neutralization activity with adenovirus 21 antisera.2Stalder H Hierholzer JC Oxman MN New human adenovirus (candidate adenovirus type 35) causing fatal disseminated infection in a renal transplant recipient.J Clin Microbiol. 1977; 6: 257-265PubMed Google ScholarWe regret the confusion caused by the incorrect identification of our isolate. The recent description of intermediate strains of adenovirus (21/H21 + 35) and our adenovirus 35 isolate, which cross reacts with type 21 antisera, illustrate the complexities inherent in adenovirus serotyping. It is possible that some adenovirus isolates reported as type 21 prior to the description of type 35 were intermediate strains or were adenovirus type 35 strains which cross reacted with type 21 antisera. To the Editor: Our case report, “Diffuse Pneumonitis Due to Adenovirus Type 21 in a Civilian,” appeared in the July 1980 issue of Chest. Subsequent to the acceptance of the manuscript, Hierholzer et al1Hierholzer JC Torrence AE Wright PF Generalized viral illness caused by an intermediate strain of adenovirus (21/H21 + 35).J Infect Dis. 1980; 141: 281-288Crossref Scopus (18) Google Scholar described an intermediate strain of adenovirus (20/H21 + 35) which was identified as adenovirus 21 by serum-neutralization tests and as types 21 and 35 by hemagglutination-inhibition tests. Adenovirus 35 is a candidate adenovirus strain currently under review by the World Health Organization. The publication by Hierholzer et al prompted us to seek confirmation of the identity of our isolate in their laboratory. It now appears that our isolate more closely resembles adenovirus 35 than adenovirus 21, although it behaved atypically for an adenovirus 35 (ie, antiserum to adenovirus 21 reacted by serum–neutralization [titer ?101 and by hemagglutination–inhibition [titer 20–801). Type 35 was not suspected earlier because the published report detailing its reactions had shown only low level hemagglutination inhibition reactivity and no serum-neutralization activity with adenovirus 21 antisera.2Stalder H Hierholzer JC Oxman MN New human adenovirus (candidate adenovirus type 35) causing fatal disseminated infection in a renal transplant recipient.J Clin Microbiol. 1977; 6: 257-265PubMed Google Scholar We regret the confusion caused by the incorrect identification of our isolate. The recent description of intermediate strains of adenovirus (21/H21 + 35) and our adenovirus 35 isolate, which cross reacts with type 21 antisera, illustrate the complexities inherent in adenovirus serotyping. It is possible that some adenovirus isolates reported as type 21 prior to the description of type 35 were intermediate strains or were adenovirus type 35 strains which cross reacted with type 21 antisera.