Recent reports have noted increased incidence of severe Ad7 disease in Asia: among the general population and pediatric inpatients in Taiwan; among persons in a military training camp in Shaanxi, China; and among those in a police training center in Kuala Lumpur, Malaysia (2-4).
HAdV typing was performed by sequencing of HAdV hexon gene hypervariable regions 1-6 ([HVR.sub.1-6]) (Ad7 reference Gomen AY594255 hexon gene nt 324-1123) (7).
This increase was predominantly related to Ad7 infections, which were first detected in November 2012 and represented 48.5% (n = 97) of all genotyped adenovirus cases in the first 7 months of 2013.
In particular, adenovirus serotype 7 (Ad7) has been associated with the most severe, often fatal, disease in children (4-7).
A nationwide outbreak of severe pneumonia caused by Ad7 occurred in Korea from 1995 to 2000 (7).
(7) reported that 2 emergent genome types of adenovirus type 7 (Ad7) had recently been detected in North American populations.
In 2002, data suggest that Ad7d2 supplanted all other Ad7 genome types (9 of 9 Ad7 isolates were A7d2) (Figure).
We present the results of that investigation and document a novel genome type of adenovirus serotype 7 (Ad7) as the etiologic agent of the outbreak.
An additional 27 unrelated Ad7 community isolates collected between 1995 and 2000 were provided by several healthcare centers in the New York City area for comparison with the outbreak strains.
Genetic variation among 166 isolates of human adenovirus 7 (Ad7) obtained from 1966 to 2000 from the United States and Eastern Ontario, Canada, was determined by genome restriction analysis.
Among recognized serotypes, Ad type 7 (Ad7) (and to a lesser extent Ad type 3) is most often associated with severe disease (2).