BackgroundThere are at least 51 adenovirus serotypes (AdV) known to cause human infections. The prevalence of the different human AdV (HAdV) serotypes varies among different regions. Presently, there are no reports of the prevalent HAdV types found in Malaysia. The present study was undertaken to identify the HAdV types associated primarily with respiratory tract infections (RTI) of young children in Malaysia.MethodsArchived HAdV isolates from pediatric patients with RTI seen at the University of Malaya Medical Center (UMMC), Kuala Lumpur, Malaysia from 1999 to 2005 were used. Virus isolates were inoculated into cell culture and DNA was extracted when cells showed significant cytopathic effects. AdV partial hexon gene was amplified and the sequences together with other known HAdV hexon gene sequences were used to build phylogenetic trees. Identification of HAdV types found among young children in Malaysia was inferred from the phylograms.ResultsAt least 2,583 pediatric patients with RTI sought consultation and treatment at the UMMC from 1999 to 2005. Among these patients, 48 (< 2%) were positive for HAdV infections. Twenty-seven isolates were recovered and used for the present study. Nineteen of the 27 (~70%) isolates belonged to HAdV species C (HAdV-C) and six (~22%) were of HAdV species B (HAdV-B). Among the HAdV-C species, 14 (~74%) of them were identified as HAdV type 1 (HAdV-1) and HAdV type 2 (HAdV-2), and among the HAdV-B species, HAdV type 3 (HAdV-3) was the most common serotype identified. HAdV-C species also was isolated from throat and rectal swabs of children with hand, foot, and mouth disease (HFMD). Two isolates were identified as corresponding to HAdV-F species from a child with HFMD and a patient with intestinal obstruction.ConclusionsHAdV-1 and HAdV-2 were the most common HAdV isolated from pediatric patients who sought treatment for RTI at the UMMC from 1999 to 2005. HAdV-B, mainly HAdV-3, was recovered from ~22% of the patients. These findings provide a benchmark for future studies on the prevalence and epidemiology of HAdV types in Malaysia and in the region.

HSV is an important neonatal pathogen. We defined the kinetics of the primary CTL response to HSV-2 in vivo in neonatal mice. Using a replication-defective HSV-2 virus, we demonstrate that neonates mount a primary HSV-specific CTL effector response in the draining LN, with delayed onset and shortened peak activity, in contrast to the rapid, strong response observed in adult mice. The shortened peak neonatal CTL response is independent of HSV dose and is associated with retarded CD8 + T cell expansion, reduced expansion of HSV-specific tetramer-positive CD8 + T cells and a reduced CD8 + T cell IFN-c response. Paradoxically, neonatal CD8 + T cells display enhanced nonspecific early activation that is not sustained. Neonatal HSV-specific TCR-transgenic CD8 + T cells showed reduced proliferation in vivo when transferred into HSV-infected neonatal mice compared to adult T cell controls. Our data suggest that early events in CD8 + T cell priming underlie the attenuated newborn CTL response to HSV.

e10213th International Congress on Infectious Diseases Abstracts, Poster Presentations 32.3% in subjects aged <10 years and 51.7% in those aged 11-20 years.Conclusion: Bangladesh has until now been deemed of high endemicity for HAV. This study indicates that a transition may be underway to intermediate endemicity. Among the high socioeconomic group, the majority (67.7%) of children aged <10 years and almost 50% of individuals aged 11-20 years were non-immune and thus at higher risk of symptomatic illness. Hepatitis A immunisation should be considered as an additional preventive intervention.