Phylogeny-based classification of human rhinoviruses detected in hospitalized children with acute lower respiratory infection in Paraguay, 2010-2011

Understanding Rhinovirus Circulation and Impact on Illness

Rhinoviruses (RVs) have been reported as one of the main viral causes for severe respiratory illnesses that may require hospitalization, competing with the burden of other respiratory viruses such as influenza and RSV in terms of severity, economic cost, and resource utilization. With three species and 169 subtypes, RV presents the greatest diversity within the Enterovirus genus, and despite the efforts of the research community to identify clinically relevant subtypes to target therapeutic strategies, the role of species and subtype in the clinical outcomes of RV infection remains unclear. This review aims to collect and organize data relevant to RV illness in order to find patterns and links with species and/or subtype, with a specific focus on species and subtype diversity in clinical studies typing of respiratory samples.

Phylogenetic characterization of rhinoviruses from infants in Sarlahi, Nepal

Problem

Rhinoviruses (RVs), the most common causes of acute respiratory infections in young children and infants, are highly diverse genetically.

Objective

To characterize the RV types detected with respiratory illness episodes in infants in Nepal.

Study methods

Infants born to women enrolled in a randomized trial of maternal influenza immunization in rural, southern Nepal were followed with household‐based weekly surveillance until 180 days of age. Infants with respiratory symptoms had nasal swabs tested for twelve respiratory viruses. A subset with RV alone was selected for sequencing of the VP4/2 gene to identify RV types.

Results

Among 547 RV‐only positive illnesses detected from December 2012 to April 2014, 285 samples (52%) were sequenced. RV‐A, B, and C species were detected in 193 (68%), 18 (6%), and 74 (26%) specimens, respectively. A total of 94 unique types were identified from the sequenced samples, including 52 RV‐A, 11 RV‐B, and 31 RV‐C. Multiple species and types circulated simultaneously throughout the study period. No seasonality was observed. The median ages at illness onset were 88, 104, and 88 days for RV‐A, B, and C, respectively. The median polymerase chain reaction cycle threshold values did not differ between RV species. No differences between RV species were observed for reported respiratory symptoms, including pneumonia, or for medical care‐seeking.

Conclusions

Among very young, symptomatic infants in rural Nepal, all three species and many types of RV were identified; RV‐A was detected most frequently. There was no association between RV species and disease severity.

RV infections were common among infants less than six months old in southern Nepal.

All three species and 94 types of RV were identified by sequencing the VP4/2 gene.

Multiple species and types circulated simultaneously throughout the study period.

No symptomatic differences between RV species or types were observed.

Respiratory Pathogens in Infants Diagnosed with Acute Lower Respiratory Tract Infection in a Tertiary Care Hospital of Western India Using Multiplex Real Time PCR

OBJECTIVE

To determine the frequency of respiratory pathogens in infants diagnosed with acute lower respiratory tract infections.

METHODS

A prospective cross-sectional observational study was conducted in infants hospitalized with a diagnosis of acute lower respiratory tract infection (ALRTI), in a tertiary care hospital in a metropolitan city of Western India. Nasopharyngeal swabs were analyzed by multiplex real time polymerase chain reaction, for 18 viruses and 3 bacteria (H. influenzae type b, C. pneumoniae and M. pneumoniae). The entire data was entered in Microsoft excel sheet and frequencies were determined.

RESULTS

One hundred eligible infants were enrolled. Pathogens were detected in 82 samples, which included Respiratory syncytial viruses (RSV) A / B (35.4%), Human rhinovirus (25.6%), Adenovirus (22%), Human Parainfluenza viruses (11%), Human bocavirus (9.8), Human metapneumovirus A / B (8.5%), Influenza A (H1N1) pdm 09 (6.1%), Parechovirus (3.7%), Human coronaviruses (3.66%), Haemophilus influenzae type b (6.1%), Chlamydia pneumoniae (2.4%) and Mycoplasma pneumoniae (2.4%). Influenza A (other than H1N1), Influenza B, Human Coronavirus 229E and Enterovirus were not detected. The rate of coinfection was 34% and rhinovirus was the most common of the multiple pathogens.

CONCLUSIONS

Spectrum of viral etiologies of ALRTI is highlighted. Etiological diagnosis of ALRTI would enable specific antiviral therapy, restrict antibiotic use and help in knowing burden of disease.

Serotype and genetic diversity of human rhinovirus strains that circulated in Kenya in 2008

Background

Human rhinoviruses (HRVs) are a well‐established cause of the common cold and recent studies indicated that they may be associated with severe acute respiratory illnesses (SARIs) like pneumonia, asthma, and bronchiolitis. Despite global studies on the genetic diversity of the virus, the serotype diversity of these viruses across diverse geographic regions in Kenya has not been characterized.

Objectives

This study sought to characterize the serotype diversity of HRV strains that circulated in Kenya in 2008.

Methods

A total of 517 archived nasopharyngeal samples collected in a previous respiratory virus surveillance program across Kenya in 2008 were selected. Participants enrolled were outpatients who presented with influenza‐like (ILI) symptoms. Real‐time RT‐PCR was employed for preliminary HRV detection. HRV‐positive samples were amplified using RT‐PCR and thereafter the nucleotide sequences of the amplicons were determined followed by phylogenetic analysis.

Results

Twenty‐five percent of the samples tested positive for HRV. Phylogenetic analysis revealed that the Kenyan HRVs clustered into three main species comprising HRV‐A (54%), HRV‐B (12%), and HRV‐C (35%). Overall, 20 different serotypes were identified. Intrastrain sequence homology among the Kenyan strains ranged from 58% to 100% at the nucleotide level and 55% to 100% at the amino acid level.

Conclusion

These results show that a wide range of HRV serotypes with different levels of nucleotide variation were present in Kenya. Furthermore, our data show that HRVs contributed substantially to influenza‐like illness in Kenya in 2008.

Phylogenetic analysis of human metapneumovirus detected in hospitalized patients in Kuwait during the years 2009-2011

BACKGROUND

Human metapneumovirus (hMPV) is an important cause of both upper and lower respiratory tract infections (RTIs) in all age groups. Children, elderly, and immunocompromised individuals are the most affected groups. HMPV infection accounts for 5% of hospitalized patients with respiratory tract infections in Kuwait. It is mostly detected among infants and elderly age groups, and both hMPV genotypes A and B circulate in Kuwait.

METHODS

In this study, the genetic diversity of detected hMPV was evaluated, and a phylogenetic analysis based on partial nucleotide and amino acid sequences of the G gene was performed for hMPV detected among hospitalized patients with RTIs.

RESULTS

Our results showed that 62% of hMPV sequences belonged to the A genotype and 38% to the B genotype. A2b and B2 subtypes were detected and circulated during the study period, whereas A1 and B1 subtypes were not detected. Based on nucleotide sequences of the G gene, most of hMPV strains (57%) were clustered with Indian strains, followed by Greek strains (24%) and Canadian strains (14%). One strain (5%) clustered within the B genotype but had different branches than B1 and B2 branches.

CONCLUSION

Our data showed the co-circulation of hMPV genotypes A2b and B2 in Kuwait with genetic diversity suggestive of evolution through negative selection.

Genetic diversity and clinical impact of human rhinoviruses in hospitalized and outpatient children with acute respiratory infection, Argentina

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Human rhinoviruses (HRV) were detected in 40% of children with ARI without comorbidities.

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HRV were identified as a risk factor associated with hospitalization (OR: 2.47).

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All HRV species co-circulated, being HRV-A and C the most frequently detected.

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Demographic and clinical outcome were similar for HRV-A and C infections.

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A high turnover rate of HRV genotypes was observed.

Background

Human rhinoviruses (HRV) are recognized as a cause of upper and lower acute respiratory infections (ARI). The circulating species and their clinical impact were not described in Argentina.

Objectives

To describe the molecular epidemiology of HRV in children and to determine the association of HRV species with outcome and severity.

Study design: Hospitalized and outpatients children <6 years old with ARI without comorbidities (n = 620) were enrolled (2008–2010). Demographic, clinical data and outcome were analyzed. HRV were identified by RT-PCR. Phylogenetic analysis and demographic reconstruction for HRV were performed in selected samples.

Results

HRV were detected in 252/620 (40.6%) of children; 8.5% in viral coinfection. Bronchiolitis (55%) and pneumonia (13%) were the most frequent clinical diagnosis. Of 202 inpatients with HRV: 72% required oxygen supplementation, 11% intensive care unit and 3% mechanical ventilation. HRV were identified as a risk factor for hospitalization (OR: 2.47).

All three HRV species were detected being HRV-A (55%) and HRV-C (43%) the most frequent; HRV-B was infrequent (2%). Of 44 sequenced HRV, 30 genotypes were detected. Seven of them were the most prevalent and circulated during limited periods of time. The demographic reconstruction revealed a constant population size and a high turnover rate of genotypes. Demographic and clinical outcome were similar for HRV-A and HRV-C infections.

Conclusion

This study highlights the clinical impact of HRV in children without comorbidities as a cause of lower ARI and hospitalization. The high frequency of HRV infections may be associated with the simultaneous circulation of genotypes and their high turnover rate.

Epidemiology, etiology, x-ray features, importance of co-infections and clinical features of viral pneumonia in developing countries

Pneumonia is still the number one killer of young children globally, accounting for 18% of mortality in children under 5 years of age. An estimated 120 million new cases of pneumonia occur globally each year. In developing countries, management and prevention efforts against pneumonia have traditionally focused on bacterial pathogens. More recently however, viral pathogens have gained attention as a result of improved diagnostic methods, such as polymerase chain reaction, outbreaks of severe disease caused by emerging pathogens, discovery of new respiratory viruses as well as the decrease in bacterial pneumonia as a consequence of the introduction of highly effective conjugate vaccines. Although the epidemiology, etiology and clinical characterization of viral infections are being studied extensively in the developed world, little data are available from low- and middle-income countries. In this paper, we review the epidemiology, etiology, clinical and radiological features of viral pneumonia in developing countries.