Isolation and identification of adenovirus in hospitalized children, under five years, with acute respiratory disease, in Havana, Cuba

A Novel Vaccine Approach for Chagas Disease Using Rare Adenovirus Serotype 48 Vectors

Due to the increasing amount of people afflicted worldwide with Chagas disease and an increasing prevalence in the United States, there is a greater need to develop a safe and effective vaccine for this neglected disease. Adenovirus serotype 5 (Ad5) is the most common adenovirus vector used for gene therapy and vaccine approaches, but its efficacy is limited by preexisting vector immunity in humans resulting from natural infections. Therefore, we have employed rare serotype adenovirus 48 (Ad48) as an alternative choice for adenovirus/Chagas vaccine therapy. In this study, we modified Ad5 and Ad48 vectors to contain T. cruzi’s amastigote surface protein 2 (ASP-2) in the adenoviral early gene. We also modified Ad5 and Ad48 vectors to utilize the “Antigen Capsid-Incorporation” strategy by adding T. cruzi epitopes to protein IX (pIX). Mice that were immunized with the modified vectors were able to elicit T. cruzi-specific humoral and cellular responses. This study indicates that Ad48-modified vectors function comparable to or even premium to Ad5-modified vectors. This study provides novel data demonstrating that Ad48 can be used as a potential adenovirus vaccine vector against Chagas disease.

Serotype determination of adenoviruses in children with respiratory infection

OBJECTIVE

To determine adenovirus serotypes among children with acute respiratory infection (ARI) in Khoozestan province, Iran during years 2010-2011.

METHODS

One hundred sixty three nasopharyngeal swabs were collected from children between 1 and 15 y who were hospitalized for the acute respiratory infection. The viral DNA was extracted from the nasopharyngeal swabs and adenoviruses were detected by Nested PCR. Positive PCR samples were sequenced in order to confirm the adenovirus serotypes.

RESULTS

Out of 163 samples, 30 (18.4 %) were positive for adenoviruses by nested PCR. Twenty two PCR products were sequenced and recognized as Ad5 and Ad2 serotypes including 19 (86.3 %) Ad5 and 3 (13.7 %) Ad2.

CONCLUSIONS

This study reveals that adenoviruses with Ad5 predominance are important cause of respiratory tract infection in children.

Adenovirus respiratory tract infections in Peru

Background

Currently, there is a paucity of data regarding human adenovirus (HAdv) circulation in Andean regions of South America. To address this shortcoming, we report the clinical, phylogenetic, and epidemiologic characteristics of HAdv respiratory tract infection from a large sentinel surveillance study conducted among adults and children in Peru.

Methods/Principal Findings

Oropharyngeal swabs were collected from participants visiting any of 38 participating health centers, and viral pathogens were identified by immunofluorescence assay in cell culture. In addition, molecular characterization was performed on 226 randomly selected HAdv samples. Between 2000 and 2010, a total of 26,375 participants with influenza-like illness (ILI) or severe acute respiratory infection (SARI) were enrolled in the study. HAdv infection was identified in 2.5% of cases and represented 6.2% of all viral pathogens. Co-infection with a heterologous virus was found in 15.5% of HAdv cases. HAdv infection was largely confined to children under the age of 15, representing 88.6% of HAdv cases identified. No clinical characteristics were found to significantly distinguish HAdv infection from other respiratory viruses. Geographically, HAdv infections were more common in sites from the arid coastal regions than in the jungle or highland regions. Co-circulation of subgroups B and C was observed each year between 2006 and 2010, but no clear seasonal patterns of transmission were detected.

Conclusions/Significance

HAdv accounted for a significant fraction of those presenting with ILI and SARI in Peru and tended to affect the younger population disproportionately. Longitudinal studies will help better characterize the clinical course of patients with HAdv in Peru, as well as determine the role of co-infections in the evolution of illness.

Molecular typing of adenovirus circulating in a Colombian paediatric population with acute respiratory infection

Human adenoviruses (HAdV) cause a broad spectrum of diseases including acute respiratory infection (ARI), and are responsible for 5% of cases requiring hospitalization in children aged <5 years in Colombia; however, little is known about the circulating types, partly due to the lack of reliable typing tests. In order to evaluate a VA gene PCR-sequencing approach for identification of HAdV circulating types in a Colombian population, 52 nasopharyngeal aspirates/swabs from children with ARI were processed. After a BLAST analysis, matches with species B (41/48, 85·42%), C (6/48, 12·5%), and D (1/48, 2·08%) were found; and at the type level, type 3 (22/48, 45·83%) was the most frequent. This initial effort to expand our knowledge about the molecular epidemiology of HAdV circulating in Bogota, Colombia, showed that HAdV-B was the predominant circulating species in the study period and reports, for the first time in Colombia, the presence of HAdV-D in a respiratory sample.

Molecular characterization of adenoviral infections in Cuba: report of an unusual association of species D adenoviruses with different clinical syndromes

Adenoviruses are common pathogens that are responsible for a wide variety of infectious syndromes. The objectives of this study were to identify and characterize members of different adenovirus species at the molecular level and to describe the correlation between viruses and clinical syndromes during a period of 4 years. Between 2002 and 2006, 45 of 512 respiratory specimens (8%) from patients with acute respiratory tract infection tested positive for adenovirus. Four adenovirus isolates from samples sent for enterovirus isolation were also analyzed. This research identified 49 confirmed cases of human adenovirus infection by PCR and/or viral culture. The most common diagnosis was upper respiratory infection (44%). Human adenovirusD was the major species found (59%), followed by Human adenovirusC (36%) and Human adenovirusB (4%). Human adenovirus 5 was the major serotype found producing bronchiolitis, followed by human adenovirus 6. In patients with upper respiratory infection, the major serotype found was human adenovirus 17. Viruses of the species Human adenovirusD were identified in seven (77%) cases of acute febrile syndrome. Four isolates from clinical materials obtained from patients with encephalitis, acute flaccid paralysis and meningoencephalitis were identified as belonging to the species Human adenovirusD. Our data demonstrate a surprising result about the identification of an unusual association of viruses of the species Human adenovirusD with different clinical syndromes. This observation could be evaluated as a possible indicator of the emergence of a novel strain but further studies are required.

A myocarditis outbreak with fatal cases associated with adenovirus subgenera C among children from Havana City in 2005

BACKGROUND

Among multiple causes of acute myocarditis, viral infection, especially that due to enteroviruses and adenoviruses, is the leading cause. In the summer 2005 an outbreak of a febrile syndrome accompanied by acute cardiac decompensation occurred in infants and young children in Havana City. Eleven patients had a rapid evolution of disease and there were 8 fatalities from cardiac failure secondary to myocarditis.

OBJECTIVE

The aim of the present study was to determine the etiological agent responsible for this outbreak.

STUDY DESIGN

Children admitted to the pediatric hospitals of Havana City from July 3 to August 2 with this clinical presentation were studied. Forty samples of necropsy tissue, cerebrospinal fluid, stools and serum were tested by molecular methods for 14 respiratory viruses, 6 herpesviruses and generic enteroviruses and flavirus and alfaviruses. Viral isolation was performed in A-549 cells. Isolated viruses were typed by sequence analysis.

RESULTS

Adenovirus genome was detected in 6 of the 8 fatal cases-the lungs in 5 (63%) and the myocardium in 3 (37%). In two fatal cases, viral genome was detected in both lung and myocardium. Adenovirus was isolated in five fatal cases. In all three non-fatal cases, adenovirus genome was detected and adenovirus was isolated into two. Sequence analysis showed that adenovirus type 5 was the only isolate from fatal cases and adenovirus 1 the only isolate in non-fatal cases. No other viruses were found by PCR or isolation techniques.

CONCLUSION

Adenovirus was the etiologic agent implicated in this myocarditis outbreak and adenovirus type 5 was associated with fatal outcome.