Respiratory viral infections among pediatric inpatients and outpatients in Taiwan from 1997 to 1999

Seasonality and risk factor analysis of respiratory syncytial virus infection in children in Taiwan-A retrospective study from 1995 to 2005

Respiratory syncytial virus (RSV) is one of the important pathogens leading to acute respiratory tract infection in infants and young children. We aimed to investigate the seasonality of RSV infection in different parts of Taiwan and to delineate the risk factors for severe RSV infections. We collected RSV-infected patients' data by retrospective chart review. A total of 1740 RSV-infected children aged under 18 years were enrolled. The infection was acquired during hospitalization in 103 (7.1%) children, while none of them required ventilator support or needed intensive care before RSV infection. The need for intensive care or ventilator support was significantly associated with congenital heart disease (CHD), chronic lung disease, and neuromuscular diseases. Age <1 year and nosocomially acquired infection are also significant predictors for the need of intensive care. Only the presence of CHD, especially acyanotic CHD, was significantly associated with a fatal outcome. RSV infection occurs all year round. Monthly distribution of RSV infections in Northern Taiwan showed a bimodal pattern, with one peak from March to May, and another from August to October. The distribution in Southern Taiwan showed a single peak from April to July. The occurrence of RSV correlates positively with temperature and rain. The bimodal seasonal distribution pattern in Northern Taiwan may be a transitional pattern shifting from a single high winter peak in temperate areas to a wider summer peak in tropical areas. Continuous surveillance is needed to explore the possible effect of global warming on the seasonality of RSV infection.

Adenovirus infection is a risk factor for recurrent intussusception in pediatric patients

BACKGROUND

Human adenoviruses are the most common pathogens to be isolated from cases of pediatric intussusception. However, the specific clinical characteristics of pediatric intussusception associated with adenovirus infection are poorly known.

METHODS

We reviewed the medical records of pediatric patients (≤18 years of age) with intussusception treated between January 2014 and December 2020. We enrolled patients with febrile episodes, 27 with and 29 without adenovirus infections (the latter serving as control group). The demographic data, clinical characteristics, and the diagnoses and management strategies were evaluated.

RESULTS

The adenovirus group exhibited a significantly longer febrile duration (4.3 ± 1.9 vs. 3.3 ± 1.1 days, p = 0.020) than the control group, with an odds ratio (OR) of 5.098 (95% confidence interval [CI] 1.223-21.254, p = 0.025). The recurrence rates were 48.1% and 13.8% in the two groups (OR 5.804; 95% CI: 1.585-21.245, p = 0.008). Most adenoviruses were non-enteric (85.2%).

CONCLUSION

Adenovirus-related intussusception is associated with a longer febrile period and a higher rate of intussusception recurrence. It is recommended that patients suspected of adenovirus-related intussusception should be observed for longer than others prior to discharge.

Comparative analysis of the clinical and epidemiological characteristics of human influenza virus versus human respiratory syncytial virus versus human metapneumovirus infection in nine provinces of China during 2009-2021

A comparative analysis of confirmed cases of human influenza virus (HIFV), human respiratory syncytial virus (HRSV), and human metapneumovirus (HMPV) was conducted to describe their clinical and epidemiological characteristics. During 2009-2021, active surveillance of acute respiratory infections (ARIs) was performed in nine provinces of China. Clinical and epidemiological information and laboratory testing results of HIFV, HRSV, and HMPV were analyzed. Among 11591 ARI patients, the single-infection rates of HIFV, HRSV, and HMPV were 15.00%, 9.59%, and 2.24%, respectively; the coinfection rate of these three viruses was 0.64%. HIFV infection was mainly in adults aged 15-59 years, accounting for 39.10%. HRSV and HMPV infections were mainly in children under 5 years old, accounting for 87.13% and 83.46%, respectively. Patients with HRSV infection were younger than HMPV. HRSV and HMPV had high similarities in clinical manifestations, presenting with lower respiratory symptoms. HIFV mainly presented with an upper respiratory infection. The epidemic peak of HRSV was earlier than that of HIFV, and that of HMPV was later than those of HRSV and HFIV. A total of 85.14% of coinfection cases were children under 5 years old. Coinfection might increase the risk of pneumonia in HIFV cases. During 2020-2021, the positive rates and seasonal patterns of these three viruses changed due to the impact of the COVID-19 pandemic. Certain clinical and epidemiological features were observed in HIFV, HRSV, and HMPV infections, which could be beneficial for guiding clinical diagnosis, treatment, and prevention of these three viruses in China.

Early Life Factors Associated with Preschool Wheezing in Preterm Infants

Advanced neonatal care has increased the survival of neonates born prematurely, and prematurity is a well-known risk factor for asthma/wheezing disorders. Thus, this prospective study aimed to determine the early life factors associated with preschool wheezing in premature neonates. Preterm neonates born between 2012 and 2017 were recruited, excluding those with bacterial infection within 7 days of life, maternal sepsis, and maternal chorioamnionitis. Birth and admission history, comorbidities, and maternal history were documented. Respiratory problems were followed-up at the neonatal outpatient department. Patients were divided into wheezing and non-wheezing groups. Data were analyzed using the Mann-Whitney test and Fisher's exact test, and multivariable logistic regression was used to define the risk factors of preschool wheezing/asthma. A total of 125 preterm infants were enrolled, including 19 in the wheezing group and 106 in the non-wheezing group. Patients in the wheezing group had longer duration of intubation (p = 0.025), higher rates for exclusive breast milk feeding (p = 0.012), and higher re-hospitalization rates for respiratory tract infections (p < 0.001), especially for respiratory syncytial virus (RSV) bronchiolitis (p = 0.045). The incidence of allergic rhinitis was also higher in the wheezing group (p = 0.005). After multivariable logistic regression, allergic rhinitis and re-hospitalization for respiratory tract infections were two significant risk factors for preschool wheezing/asthma in premature neonates. Close follow-up of premature infants at high risk for asthma susceptibility is recommended.

Comparative analysis of clinical features of SARS-CoV-2 and adenovirus infection among children

BACKGROUND

The new emerging coronavirus disease 2019 (COVID-19) overall shares similar symptoms with other common respiratory viral infections. We aimed in this study to compare COVID-19 and human adenovirus (HAdV) infections in pediatric patients regarding the frequencies of major clinical symptoms and the potential disparities in laboratory and imaging parameters.

METHODS

Following a case-control-like design, we built 72 age-matched pediatric COVID-19 and HAdV patient pairs. Their early symptoms and laboratory and imaging characteristics were then retrieved and compared.

RESULTS

Fever and cough were the most common symptoms for both infections but were seen more often in HAdV than in COVID-19 patients (92% vs. 66% and 60% vs. 18%, respectively). Compared with COVID-19 patients, children with HAdV infection had statistically significantly higher values of neutrophil count, neutrophil percentage, activated partial thromboplastin time, prothrombin time, lactate dehydrogenase, C-reactive protein, procalcitonin but lower values of lymphocyte percentage, total bilirubin, potassium and sodium. Thoracic computed tomography also revealed more anomalies in HAdV patients than in COVID-19 patients (95% vs. 67%).

CONCLUSIONS

COVID-19 is an overall less symptomatic and less severe infection at admission compared to HAdV respiratory infection in pediatric population.

Incidence and clinical features of viral sore throat among children in rural Haryana, India

Background

Sore throat is one of the commonest symptoms that patients present to a primary care physician. We describe the epidemiology of sore throat and performance of an algorithm to predict viral sore throat in a part of India.

Methods

Children below 10 years of age were followed in 4 villages of Haryana, India from Aug 2012 to Aug 2014 through weekly domiciliary visits by trained field workers who screened for symptoms of acute respiratory infection (ARI) including sore throat. Nasal and throat swabs were obtained from a random sample of sore throat cases by nurses and sent in appropriate transport media for real-time polymerase chain reaction for detection of viral nucleic acid. Incidence of sore throat and viral sore throat are reported as number of sore throat episodes per 1000 child-years (EPTCY) with 95% confidence-interval (CI). Symptoms, associated with viral sore throat were identified by logistic regression, combined into a clinical score and Receiver Operating Characteristic curve was plotted.

Results

Over a two-year period, 3765 children were followed up for 5578 child years. 1069 episodes of sore throat were reported, and swabs were collected from 8% of the cases randomly. The incidence of sore throat and viral sore throat was 191.7 (95%CI: 180.5-203.6) and 60.1 (95%CI: 55.1-68.2) EPTCY, respectively. Fever (aOR 5.40,95%CI: 1.16-25.18) and running nose (aOR 10.16,95%CI: 1.01-102.42) was significantly associated with viral sore throat. The clinical score (fever, running nose, and headache) had an overall sensitivity of 86.2% (68.3-96.1%), specificity of 62% (47.2-75.3%) and AUC of 0.78 (0.67-0.87) in predicting viral sore throat.

Conclusion

Viruses contributed to one-third of burden of sore throat and clinical score can be used in primary care settings to aid antibiotic prescription by physicians.

A review on disease burden and epidemiology of childhood parainfluenza virus infections in Asian countries

Human parainfluenza viruses (HPIVs) are an important cause of acute respiratory tract infections (ARTIs) in children less than 5 years, second only to human respiratory syncytial viruses (HRSVs). Generally, patients infected with HPIVs are treated in outpatient clinics, yet also contribute to ARTI-associated hospitalization in children. Although HPIV infections are well studied in developed countries, these infections remain under-investigated and not considered in the routine laboratory diagnosis of childhood ARTI in many developing countries in Asia. We performed an extensive literature search on the prevalence, epidemiology, and burden of HPIV infections in children less than 5 years in Asia using PubMed and PubMed Central search engines. Based on the literature, the prevalence of HPIV infection in Asia ranges from 1% to 66%. According to many studies, HPIV-3 is the major virus circulating among children; however, several studies failed to detect HPIV-4 due to unavailability of diagnostic tools. In Asian countries, HPIV contributes a substantial disease burden in children. The data in this review should assist researchers and public health authorities to plan preventive measures, including accelerating research on vaccines and antiviral drugs.

Adenovirus load correlates with respiratory disease severity among hospitalized pediatric patients

OBJECTIVES

Human adenoviruses (HAdVs) are common pathogens that can cause respiratory, gastrointestinal and other infections. We investigated the correlation between adenovirus viral load in clinical respiratory samples and the respiratory disease severity in pediatric patients.

METHODS

Medical records of patients hospitalized in the Sheba Medical Center (SMC) with confirmed adenovirus infection were retrospectively analyzed. The possible correlation between disease severity score and Real time PCR 'cycle threshold' (Ct), a proxy of viral load, was assessed in patients aged 9 years and under. In addition, Ct values of hospitalized versus community-care patient samples, positive for various respiratory viruses including adenovirus, were compared.

RESULTS

Adenovirus load in respiratory samples, as measured by Ct values, was found to be negatively correlated with respiratory disease severity in hospitalized pediatric patients aged under 9 years. Moreover, hospitalized patients presented with significantly higher Ct levels for various respiratory viruses as compared to community-care patients.

CONCLUSION

In this study we found a correlation between Ct values obtained from adenovirus q-PCR analysis of respiratory clinical samples and disease severity in patients aged 9 years and under. Such finding may serve as a predictor of respiratory disease course in pediatric patients and will be beneficial for the differential diagnosis and treatment of pediatric patients.

Human coronavirus OC43 and other respiratory viruses from acute respiratory infections of Egyptian children

Respiratory infections have a significant impact on health worldwide. Viruses are major causes of acute respiratory infections among children. Limited information regarding its prevalence in Egypt is available. This study investigated prevalence of 10 respiratory viruses; Adenovirus, influenza A, B, respiratory syncytial virus (RSV), Parainfluenza virus (PIV)type 1-4, enterovirus, and human coronavirus OC43 (HCoV-OC43) among children in Alexandria, Egypt presenting with acute lower respiratory tract infections.The study was conducted on children <14 years of age selected from ElShatby Pediatric Hospital, Alexandria University, Egypt. One hundred children presenting during winter season with influenza-like illness were eligible for the study. Oropharyngeal swabs were collected and subjected to viral RNA and DNA extraction followed by polymerase chain reaction.Viral infections were detected in 44% of cases. Adenovirus was the most common, it was found in 19% of the patients. Prevalence of PIV (3 and 4) and enterovirus was 7% each. Prevalence of RSV and HCoV-OC43 was 5% and 3% respectively. Two percentage were Influenza A positive and 1% positive for influenza B. Mixed viral infection was observed in 7%.To the best of our knowledge, this is the first report of the isolation of HCoV-OC43 from respiratory infections in Alexandria, Egypt.

Six-monthly palivizumab prophylaxis effectively reduced RSV-associated hospitalization rates of preterm infants in a subtropical area: a population-based cohort study

BACKGROUND

To evaluate the effects of 6-monthly palivizumab on respiratory syncytial virus-associated hospitalization (RSVH) in preterm infants in an area without RSV seasonality.

METHODS

RSV prophylaxis with 6-monthly palivizumab in infants born at gestational age (GA) ≤28 weeks or those born at GA 29-35 weeks with bronchopulmonary dysplasia (BPD) was implemented in Taiwan since 2010. RSVH, use of mechanical ventilation (MV), admission to intensive care unit (ICU), length of hospital stay, and annual mortality were compared between the historical control group (no prophylaxis, 2008-2009) and the prophylaxis group (2011-2013).

RESULTS

The annual RSVH rates decreased in the target population and in subgroups of infants who received prophylaxis (all target infants: odds ratio [OR], 0.43; 95% confidence interval [CI], 0.29-0.65). No difference was observed in MV and ICU usage and 1-year mortality in the ≤28 weeks subgroup. In the GA 29-35 weeks with BPD subgroup, ICU usage and 1-year mortality rates were significantly reduced with palivizumab prophylaxis regimen. A significant decrease was noted in the annual mortality and ICU admission rates of infants who received prophylactic treatment.

CONCLUSION

Six-monthly palivizumab treatment reduced the RSVH rate, ICU usage, and annual mortality rates of target infants in an area without RSV seasonality.

Molecular detection of respiratory pathogens among children aged younger than 5 years hospitalized with febrile acute respiratory infections: A prospective hospital-based observational study in Niamey, Niger

BACKGROUND AND AIMS

In Niger, acute respiratory infections (ARIs) are the second most common cause of death in children aged younger than 5 years. However, the etiology of ARI is poorly understood in the country. This study aims to describe viral and bacterial infections among children aged younger than 5 years hospitalized with febrile ARI at two hospitals in Niamey, Niger's capital city, and the reported clinical procedures.

METHODS

We conducted a prospective study among children aged younger than 5 years hospitalized with febrile ARI at two national hospitals in Niamey between January and December 2015. Clinical presentation and procedures during admission were documented using a standardized case investigation form. Nasopharyngeal specimens collected from each patient were tested for a panel of respiratory viruses and bacteria using the Fast Track Diagnostic 21 Plus kit.

RESULTS

We enrolled and tested 638 children aged younger than 5 years, of whom 411 (64.4%) were aged younger than 1 year, and 15 (2.4%) died during the study period. Overall, 496/638 (77.7%) specimens tested positive for at least one respiratory virus or bacterium; of these, 195 (39.3%) tested positive for respiratory viruses, 126 (25.4%) tested positive for respiratory bacteria, and 175 (35.3%) tested positive for both respiratory viruses and bacteria. The predominant viruses detected were respiratory syncytial virus (RSV) (149/638; 23.3%), human parainfluenza virus (HPIV) types 1 to 4 (78/638; 12.2%), human rhinovirus (HRV) (62/638; 9.4%), human adenovirus (HAV) (60/638; 9.4%), and influenza virus (INF) (52/638; 8.1%). Streptococcus pneumoniae (249/638; 39.0%) was the most frequently detected bacterium, followed by Staphylococcus aureus (112/638; 12.2%) and Haemophilus influenzae type B (16/638; 2.5%). Chest X-rays were performed at the discretion of the attending physician on 301 (47.2%) case patients. Of these patients, 231 (76.7%) had abnormal radiological findings. A total of 135/638 (21.2%) and 572/638 (89.7%) children received antibiotic treatment prior to admission and during admission, respectively.

CONCLUSION

A high proportion of respiratory viruses was detected among children aged younger than 5 years with febrile ARI, raising concerns about excessive use of antibiotics in Niger.

Comparative study of clinical and epidemiological characteristics of major pediatric adenovirus epidemics in southern Taiwan

Background

Human adenoviruses (HAdV) are important pathogens of pediatric respiratory tract infections in Taiwan. There were two major HAdV epidemics in southern Taiwan in 2011 and 2014, respectively.

Methods

The demographic, clinical characteristics, and risk factors for hospitalization of pediatric patients with HAdV infection in the two outbreaks were retrospectively compared. The epidemic was defined as > 7% HAdV detection rate for six consecutive weeks. HAdV infection was defined as positive HAdV isolates from respiratory tract specimens. HAdV genotype was determined by PCR-based hexon gene sequencing.

Results

A total of 1145 pediatric patients were identified (635 cases in 2011; 510 cases in 2014). HAdV genotype 3 and 7 contributed to both epidemics, although the proportion of HAdV3 decreased significantly (64.7% in 2011 to 25.5% in 2014, p < 0.001) and was replaced by other genotypes (type 1, 4, and 6) in the 2014 epidemic. Among the hospitalized patients, there were more patients hospitalized with bronchopneumonia/or pneumonia in the 2011 epidemic (10.6% vs 5.1%, p < 0.001), while more patients hospitalized with acute pharyngitis/pharyngoconjunctival fever (63.9% vs. 38.6%, p < 0.001) in the 2014 epidemic. In both epidemics, hospitalized patients had higher WBC and C-reactive protein (CRP) levels than non-hospitalized patients. Using multivariate regression analysis, underlying disease and elevated CRP levels were independent risk factors for hospitalization in both epidemics.

Conclusion

There were significant differences in clinical, viral characteristics and risk factors of hospitalization between the 2011 and 2014 epidemics. Understanding changes in the epidemiological and clinical characteristics of HAdV epidemics is important from a public health perspective.

Prevalence, risk factors and clinical characteristics of respiratory syncytial virus-associated lower respiratory tract infections in Kelantan, Malaysia

Respiratory syncytial virus (RSV) is a common pathogen affecting the respiratory tract in infants. To date, there is limited data on RSV occurrence in Malaysia especially in the northeast of Peninsular Malaysia which is significantly affected by the rainy (monsoon) season. This study aimed to determine the prevalence, risk factors (the presence of a male sibling and older school-age siblings, parental education level, monthly income, chronic lung disease, immunocompromised, being a passive smoker, multipara, breastfeeding, prematurity, congenital heart disease, nursery attendance, and rainy season) as well as clinical manifestations of RSV in hospitalized infants and children with lower respiratory tract infection (LRTI). Patients' nasopharyngeal aspirates were tested for RSV antigen, questionnaires, and seasonal variations were used to assess RSV infection. Approximately 22.6% of children were infected with RSV; mean age 7.68 ± 5.45 months. The peak incidence of RSV as a causative agent for LRTI in infants was less than or equal to 1-year old (83%) with approximately 50.5% of the affected children in the younger age group (6 months amd below). RSV infection was significantly but independently associated with the rainy season (odds ratio, 3.307; 95% confidence interval, 1.443-3.688; P < 0.001). The infection was also associated ( P < 0.05) with a higher number of severe clinical courses, poor feeding, vomiting, increased need for medical care and a shorter mean duration of symptoms before hospital admission. Our study suggested administration of the passive prophylaxis for RSV to high-risk infants during the rainy season in the months of October to January.

Incidence and seasonality of respiratory viruses causing acute respiratory infections in the Northern United Arab Emirates

Background

The data on the seasonality of respiratory viruses helps to ensure the optimal vaccination period and to monitor the possible outbreaks of variant type.

Objectives

This study was designed to describe the molecular epidemiology and seasonality of acute respiratory infection (ARI)‐related respiratory viruses in the United Arab Emirates (UAE).

Methods

Both upper and lower respiratory specimens were collected for the analysis from all the patients who visited the Sheikh Khalifa Specialty Hospital (SKSH) with ARI for over 2 years. The multiplex real‐time reverse transcription polymerase chain reaction (rRT‐PCR) test was used to detect respiratory viruses, which include human adenovirus, influenza virus (FLU) A and B, respiratory syncytial virus, parainfluenza viruses, human rhinovirus (HRV), human metapneumovirus, human enterovirus, human coronavirus, and human bocavirus.

Results

A total of 1,362 respiratory samples were collected from 733 (53.8%) male and 629 (46.2%) female patients with ARI who visited the SKSH between November 2015 and February 2018. The rRT‐PCR test revealed an overall positivity rate of 37.2% (507/1362). The positive rate increased during winter; it was highest in December and lowest in September. FLU was the most frequently detected virus (273/1362 [20.0%]), followed by human rhinovirus (146/1362 [10.7%]). The FLU positivity rate showed two peaks, which occurred in August and December. The peak‐to‐low ratio for FLU was 2.26 (95% confidence interval: 1.52‐3.35).

Conclusions

The pattern of FLU in the UAE parallels to that of temperate countries. The trend of the small peak of FLU in the summer suggests a possibility of semi‐seasonal pattern in the UAE.

Prevalence of airway hyperresponsiveness and its seasonal variation in children with asthma

BACKGROUND

Airway hyperresponsiveness (AHR) is a key feature of asthma and can be detected using various bronchoprovocation tests. In pediatric populations, the percentage of a positive methacholine challenge test (MCCTs) in children with asthma varies among studies, and some have reported seasonal variability. However, these studies have mostly been conducted in temperate regions. This study evaluated the prevalence of AHR to methacholine and its seasonal variation in asthmatic children in Taiwan, a subtropical country.

METHODS

A total of 276 children with asthma and their MCCT results were retrospectively reviewed. All were diagnosed with asthma and received asthma controllers regularly. They were assigned to four season groups depending in which season MCCTs were administered, with seasons categorized by the Central Weather Bureau of Taiwan. Subgroup analyses, including for sex, age, and atopy level, were compared for seasonal difference.

RESULTS

The prevalence of methacholine hyperresponsiveness was 70.7% (n = 195), and the children who were younger and had higher total serum IgE were more sensitive to methacholine (p = 0.019 and p < 0.005, respectively). No significant difference in AHR prevalence among seasons was observed (p = 0.480). The percentage of borderline, mild, and moderate severity of MCCT results was almost equally distributed among the seasons. In subgroup analysis, the children with a higher IgE level (≥75th percentile of all data) had a higher proportion of positive MCCTs in summer (88.6%, p = 0.016).

CONCLUSION

In total, 70% of the children with asthma in Taiwan had AHR to methacholine, which varied among seasons. Children with a higher total serum IgE level may be more seasonally dependent, particularly in summer.

Literature review of the epidemiology of influenza B disease in 15 countries in the Asia-Pacific region

Influenza control strategies focus on the use of trivalent influenza vaccines containing two influenza A virus subtypes and one of the two circulating influenza type B lineages (Yamagata or Victoria). Mismatches between the vaccine B lineage and the circulating lineage have been regularly documented in many countries, including those in the Asia‐Pacific region. We conducted a literature review with the aim of understanding the relative circulation of influenza B viruses in Asia‐Pacific countries. PubMed and Western Pacific Region Index Medicus were searched for relevant articles on influenza type B published since 1990 in English language for 15 Asia‐Pacific countries. Gray literature was also accessed. From 4834 articles identified, 121 full‐text articles were analyzed. Influenza was reported as an important cause of morbidity in the Asia‐Pacific region, affecting all age groups. In all 15 countries, influenza B was identified and associated with between 0% and 92% of laboratory‐confirmed influenza cases in any one season/year. Influenza type B appeared to cause more illness in children aged between 1 and 10 years than in other age groups. Epidemiological data for the two circulating influenza type B lineages remain limited in several countries in the Asia‐Pacific, although the co‐circulation of both lineages was seen in countries where strain surveillance data were available. Mismatches between circulating B lineages and vaccine strains were observed in all countries with available data. The data suggest that a shift from trivalent to quadrivalent seasonal influenza vaccines could provide additional benefits by providing broader protection.

Clinico-Aetiological Study of Severe and Very Severe Pneumonia in Two Months to Five Years Children in a Tertiary Health Care Centre in Odisha, India

Introduction

Pneumonia is a major cause of mortality under five-year-old children. In spite of recent advances in management, there is paucity of data on clinical, aetiological profile of severe and very severe pneumonia among under five-year-old children in developing countries.

Aim

To determine the clinico-aetiological factors of severe and very severe pneumonia and its outcome in children aged two -months to five-years in a tertiary health care centre in Odisha, India.

Materials and Methods

This was a prospective observational study. All the patients between two-months to five-years age admitted to SCB Medical College, Cuttack, Odisha, India, were screened for features of severe and very severe pneumonia based on WHO diagnostic criteria, over a one year period. Out of 10300 patients admitted to our hospital during the study period; 141 cases were included in the study. Their clinical parameters were recorded and were followed up till discharge or death. Continous variables were analyzed using Student t-test or Mann-Whitney U test whereas categorical data were analyzed using Pearson Chi square test or Fischer Exact test.

Results

Out of 141 patients included in the study, cough, tachypnea and chest retractions were present in 100% cases while fever in 97.1% (137) cases. In 17% (24) cases, bacterial pathogen was isolated. Most common organism being Staphylococcus aureus 8.51% (12) followed by Streptococcus pneumonie 6.4% (9). Higher mortality 11.34% (16) was found among patients presenting after three days of illness (p=0.048). About 17% (24) patients developed complications. Common complications were sepsis 5.6% (8), CCF 4.2% (6) and empyema 4.2% (6). Higher mortality 22 (15.6%) was observed in very severe pneumonia group (p=0.003).

Conclusion

The incidence of severe and very severe pneumonia was higher in infancy. Rainy and winter season were associated with higher incidence of disease. Bottle feeding practice and smoking were significantly associated with more severe disease. Death rate was high among patients admitted to hospital after three days of onset of illness, so early referral is indicated for better outcome.

Surveillance of upper respiratory infections using a new multiplex PCR assay compared to conventional methods during the influenza season in Taiwan

OBJECTIVES

To improve diagnosis as part of laboratory surveillance in Taiwan, influenza-like illness (ILI) surveillance was conducted using a new multiplex PCR assay (FilmArray) and the results compared to those of conventional methods The study was performed during the winter months.

METHODS

Throat swabs from patients with an ILI presenting to physicians in sentinel practices were collected during the 2016-2017 influenza season.

RESULTS

A total of 52 samples tested positive by FilmArray Respiratory Panel. Forty percent were influenza A virus, and subtype H3N2 virus was the major epidemic strain. However, nearly 60% of ILI cases seen at sentinel sites were caused by non-influenza pathogens. The results of the FilmArray assay and cell culture were identical, and this assay was more sensitive than a rapid influenza diagnostic test. Genetic analyses revealed new influenza A H3N2 variants belonging to a novel subclade 3C.2a2.

CONCLUSIONS

The FilmArray assay facilitates urgent testing and laboratory surveillance for common viral and bacterial respiratory pathogens. This study demonstrated the use of a highly sensitive assay using clinical samples that is feasible for application worldwide. This may lead to an increased rate of diagnosis of viral infections and to improved patient outcomes, and in particular to a reduction in the overuse of antibiotics and antivirals.

Clinical and epidemiological characteristics of human parainfluenza virus infections of children in southern Taiwan

BACKGROUND

Human parainfluenza viruses (HPIV) 1-4 had been analyzed as being one of the most frequent causes of hospitalizations for young children with respiratory tract illnesses.

METHODS

This retrospective study was performed from children virologically confirmed as HPIV infection through throat swab or nasopharyngeal aspirates at a tertiary care university hospital, between January 2012 and December 2014. HPIV4 was not checked and analyzed, due to not include in the commercial kit. The demographic, epidemiological, clinical presentations, diagnosis, treatment, outcomes, and laboratory data were analyzed.

RESULTS

Totally 398 cases were enrolled, including 39 (9.8%) of HPIV1, 67 (16.8%) of HPIV2, and 292 (73.4%) of HPIV3. The mean age of HPIV-infected children was 2.9 year-old, and 50.5% were among one to three year-old. A total of 56.8% HPIV3-infected children were among one to three years old, however, no HPIV2-infected children was younger than one year-old. The HPIV1-infected patients were more common to develop wheezing and diagnose as acute bronchiolitis. HPIV2-infected children were more likely to have hoarseness (23.9%), and were associated with croup (25.4%). HPIV3 was isolated from two fatal cases, with neurological underlying diseases.

CONCLUSION

The impact caused by HPIVs infections is significant in hospitalized children. In the current study, our results contribute to the epidemiologic, clinical and laboratory information of HPIV infection in children in the important areas of respiratory tract infection that could support the development of optimization management.

Genetic variation in chromosome Y regulates susceptibility to influenza A virus infection

Males of many species, ranging from humans to insects, are more susceptible than females to parasitic, fungal, bacterial, and viral infections. One mechanism that has been proposed to account for this difference is the immunocompetence handicap model, which posits that the greater infectious disease burden in males is due to testosterone, which drives the development of secondary male sex characteristics at the expense of suppressing immunity. However, emerging data suggest that cell-intrinsic (chromosome X and Y) sex-specific factors also may contribute to the sex differences in infectious disease burden. Using a murine model of influenza A virus (IAV) infection and a panel of chromosome Y (ChrY) consomic strains on the C57BL/6J background, we present data showing that genetic variation in ChrY influences IAV pathogenesis in males. Specific ChrY variants increase susceptibility to IAV in males and augment pathogenic immune responses in the lung, including activation of proinflammatory IL-17-producing γδ T cells, without affecting viral replication. In addition, susceptibility to IAV segregates independent of copy number variation in multicopy ChrY gene families that influence susceptibility to other immunopathological phenotypes, including survival after infection with coxsackievirus B3. These results demonstrate a critical role for genetic variation in ChrY in regulating susceptibility to infectious disease.

The potential influence of human parainfluenza viruses detected during hospitalization among critically ill patients in Kuwait, 2013-2015

BACKGROUND

The four types of human parainfluenza viruses (PIV) are important causes of community-acquired pneumonia, particularly in children; however, limited information exists about the incidence of PIV in critically ill patients. The aim of this study is to describe the spectrum, incidence and clinical features of PIV-associated infections diagnosed during the hospital stay of patients admitted to pediatric intensive care unit (PICU) and intensive care unit (ICU) of 5 medical centers across Kuwait.

METHODS

This was a population-based, retrospective study from 2013 to 2015. Specimens were analyzed by molecular methods. This analysis was performed using the database of Virology Unit, Mubarak Al-Kabeer Hospital. Data from 1510 admitted patients with suspected respiratory viral infections was extracted.

RESULTS

The database contained a total of 39 (2.6%) patients infected with PIV (53.8% male and 46.2% females) and 20 (51.3%) were under 1 year of age. The most frequently isolated type was type 3 (28, 71.8%) followed by type 1 (9, 23.1%). At admission the most common clinical diagnosis was pneumonia in 12 patients (30.8%, p < 0.05) followed by bronchiolitis in 10 patients (25.6%).

CONCLUSION

PIV plays an important yet unrecognized role in the outcomes of PIUC and ICU patients. Our results contribute to the limited epidemiologic data of PIV in PIUC and ICU in this region.

Objective measurement of frequency and pattern of nocturnal cough in children with asthma exacerbation

BACKGROUND

Although a number of patients with asthma report experiencing persistent cough during sleep, it has not yet been objectively investigated.

OBJECTIVE

To classify cough severity and evaluate a characteristic pattern of cough frequency in children with asthma using an objective cough monitoring system.

METHODS

An objective cough monitoring system that specialized in children was used to measure cough frequency and nocturnal cough patterns. Coughs were recorded with microphone and accelerometer and analyzed using a customized software program. The number of nocturnal coughs and the pattern of cough frequency in 30-minute intervals were measured along with the severity of each asthma exacerbation, and the results were compared with children without asthma.

RESULTS

The total overnight cough count of 34 children with asthma was higher than that of 15 children without asthma (P < .001). The total overnight cough count in children with severe asthma exacerbation was higher than that in children with moderate asthma exacerbation (P < .05). The cough counts were significantly increased at the time of falling asleep and waking. This pattern was not observed in children without asthma. The total cough counts and cough patterns in children with asthma were not affected by sex, age, cause of asthma exacerbation, or therapy.

CONCLUSION

Our data indicate huge cough counts and characteristic nocturnal cough patterns in children with asthma. Objective and precise cough monitoring is useful for the management of childhood asthma.

Molecular Epidemiology and Clinical Manifestations of Adenovirus Respiratory Infections in Taiwanese Children

Human adenoviruses (HAdVs) are important causes of respiratory infections in children. They usually cause mild upper respiratory symptoms, but they can also produce severe pneumonia and other complications. The aims of this retrospective study were to better define the molecular epidemiology of respiratory adenoviruses circulating in Taiwanese children during 2002 and 2013, detect reinfections and co-infections, and characterize the clinical features and laboratory findings according to the causative genotypes.We collected a representative sample of 182 isolates of adenoviruses from 175 children during the 12-year study period. The most prevalent species was HAdV-B genotype 3 (HAdV-3) (92/182, 50.5%) followed by HAdV-C (HAdV-2) (38/182, 20.9%). A single outbreak of HAdV-E (6/182, 3.3%) was noted in 2007. The mean age of children with adenovirus infections was 3.7 ± 2.0 years, with a slight predominance of males (53.1%). Children with HAdV-B tended to be older, had more lower respiratory tract infections, gastrointestinal symptoms, and a higher rate of hospitalization than those with HAdV-C (P < 0.05). Adenovirus co-infections were noted in 25/175 (14.3%) of the children. The most frequent co-infections were with species B (HAdV-3) and C (HAdV-2) (14/25, 56.0%). Additional infections were noted in 23/175 (13.1%) of the children. Of these repeated infections, the initial isolates were always genotypes of HAdV-C. The second isolates were genotypes of HAdV-B or HAdV-E. The clinical features of the first HAdV-B infection and the reinfection of HAdV-B followed the HAdV-C were similar.In conclusion, HAdV-B, C, and E were the only adenovirus species that were isolated from children who were sufficiently ill with respiratory infections to require a visit to the hospital. Human adenovirus B (HAdV-3) accounted for half of these species. HAdV-B was more likely than other species to produce severe disease. The high incidence of adenovirus co-infection and reinfections with different HAdV species supports the need for continued surveillance and has major implications for development of vaccines.

Rhinoviruses and Respiratory Enteroviruses: Not as Simple as ABC

Rhinoviruses (RVs) and respiratory enteroviruses (EVs) are leading causes of upper respiratory tract infections and among the most frequent infectious agents in humans worldwide. Both are classified in the Enterovirus genus within the Picornaviridae family and they have been assigned to seven distinct species, RV-A, B, C and EV-A, B, C, D. As viral infections of public health significance, they represent an important financial burden on health systems worldwide. However, the lack of efficient antiviral treatment or vaccines against these highly prevalent pathogens prevents an effective management of RV-related diseases. Current advances in molecular diagnostic techniques have revealed the presence of RV in the lower respiratory tract and its role in lower airway diseases is increasingly reported. In addition to an established etiological role in the common cold, these viruses demonstrate an unexpected capacity to spread to other body sites under certain conditions. Some of these viruses have received particular attention recently, such as EV-D68 that caused a large outbreak of respiratory illness in 2014, respiratory EVs from species C, or viruses within the newly-discovered RV-C species. This review provides an update of the latest findings on clinical and fundamental aspects of RV and respiratory EV, including a summary of basic knowledge of their biology.

Viral Respiratory Tract Infections in Adult Patients Attending Outpatient and Emergency Departments, Taiwan, 2012-2013: A PCR/Electrospray Ionization Mass Spectrometry Study

Viral etiologies of respiratory tract infections (RTIs) have been less studied in adult than in pediatric populations. Furthermore, the ability of PCR/electrospray ionization mass spectrometry (PCR/ESI-MS) to detect enteroviruses and rhinoviruses in respiratory samples has not been well evaluated. We sought to use PCR/ESI-MS to comprehensively investigate the viral epidemiology of adult RTIs, including testing for rhinoviruses and enteroviruses. Nasopharyngeal or throat swabs from 267 adults with acute RTIs (212 upper RTIs and 55 lower RTIs) who visited a local clinic or the outpatient or emergency departments of a medical center in Taiwan between October 2012 and June 2013 were tested for respiratory viruses by both virus isolation and PCR/ESI-MS. Throat swabs from 15 patients with bacterial infections and 27 individuals without active infections were included as control samples. Respiratory viruses were found in 23.6%, 47.2%, and 47.9% of the 267 cases by virus isolation, PCR/ESI-MS, and both methods, respectively. When both methods were used, the influenza A virus (24.3%) and rhinoviruses (9.4%) were the most frequently identified viruses, whereas human coronaviruses, human metapneumovirus (hMPV), enteroviruses, adenoviruses, respiratory syncytial virus, and parainfluenza viruses were identified in small proportions of cases (<5% of cases for each type of virus). Coinfection was observed in 4.1% of cases. In the control group, only 1 (2.4%) sample tested positive for a respiratory virus by PCR/ESI-MS. Patients who were undergoing steroid treatment, had an active malignancy, or suffered from chronic obstructive pulmonary disease (COPD) were at risk for rhinovirus, hMPV, or parainfluenza infections, respectively. Overall, immunocompromised patients, patients with COPD, and patients receiving dialysis were at risk for noninfluenza respiratory virus infection. Rhinoviruses (12.7%), influenza A virus (10.9%), and parainfluenza viruses (7.3%) were the most common viruses involved in the 55 cases of lower RTIs. The factors of parainfluenza infection, old age, and immunosuppression were independently associated with lower RTIs. In conclusion, PCR/ESI-MS improved the diagnostic yield for viral RTIs. Non-influenza respiratory virus infections were associated with patients with comorbidities and with lower RTIs. Additional studies that delineate the clinical need for including non-influenza respiratory viruses in the diagnostic work-up in these populations are warranted.

Molecular Epidemiology and Phylogenetic Analysis of Human Adenovirus Caused an Outbreak in Taiwan during 2011

An outbreak of adenovirus has been surveyed in Taiwan in 2011. To better understand the evolution and epidemiology of adenovirus in Taiwan, full-length sequence of hexon and fiber coapsid protein was analyzed using series of phylogenetic and dynamic evolution tools. Six different serotypes were identified in this outbreak and the species B was predominant (HAdV-3, 71.50%; HAdV-7, 15.46%). The most frequent diagnosis was acute tonsillitis (54.59%) and bronchitis (47.83%). Phylogenetic analysis revealed that hexon protein gene sequences were highly conserved for HAdV-3 and HAdV-7 circulation in Taiwan. However, comparison of restriction fragment length polymorphism (RFLP) analysis and phylogenetic trees of fiber gene in HAdV-7 clearly indicated that the predominant genotype in Taiwan has shifted from 7b to 7d. Several positive selection sites were observed in hexon protein. The estimated nucleotide substitution rates of hexon protein of HAdV-3 and HAdV-7 were 0.234×10^-3 substitutions/site/year (95% HPD: 0.387~0.095×10^-3) and 1.107×10^-3 (95% HPD: 0. 541~1.604) respectively; those of the fiber protein of HAdV-3 and HAdV-7 were 1.085×10^-3 (95% HPD: 1.767~0.486) and 0.132×10^-3 (95% HPD: 0.283~0.014) respectively. Phylodynamic analysis by Bayesian skyline plot (BSP) suggested that using individual gene to evaluate the effective population size might possibly cause miscalculation. In summary, the virus evolution is ongoing, and continuous surveillance of this virus evolution will contribute to the control of the epidemic.

Conjunctival geographic ulcer: an overlooked sign of herpes simplex virus infection

Herpes simplex virus (HSV) ocular infection causes significant visual burden worldwide. Despite the fact that dendritic or geographic corneal ulcers are typical findings in HSV epithelial keratitis, conjunctival ulcer as a sign of HSV infection has rarely been reported. Although easily overlooked, this important sign could be enhanced by fluorescein staining. We report two cases of conjunctival geographic ulcers proven to be HSV infection by viral isolation and polymerase chain reaction (PCR). One patient had bilateral disease and blepharitis, and the other had unilateral involvement without skin lesions. With timely diagnosis and proper management, excellent visual outcome can be expected.

Comparison of throat swab and nasopharyngeal aspirate specimens for rapid detection of adenovirus

Nasopharyngeal aspirate (NPA) and throat swab (TS) specimens from individual patients were compared with regard to usefulness for adenovirus detection. In 153 adenovirus-infected patients, rapid test sensitivities with NPAs (90.8%) were nearly equivalent to those with TSs (91.5%) based on real-time polymerase chain reaction standards, indicating that NPAs are equally useful.

Comparisons of etiology and diagnostic tools of lower respiratory tract infections in hospitalized young children in Southern Taiwan in two seasons

BACKGROUND

Lower respiratory tract infections (LRTIs) play an important role in pediatric diseases; however, there are limited data about LRTIs in Southern Taiwan. This study aimed to investigate the clinical and epidemiological data of LRTIs in this area.

METHODS

Children aged under 5 years who were hospitalized at a medical center in Southern Taiwan with acute LRTIs from July 2010 to October 2010 (summer) and from March 2011 to May 2011 (spring) were prospectively enrolled. Nasopharyngeal aspirates were obtained and sent for viral cultures, multiplex polymerase chain reaction (PCR), and traditional quick tests. The clinical features, laboratory data, and imaging findings were recorded and analyzed.

RESULTS

A total of 90 children were enrolled, 70 of whom had detectable pathogens. The positive rate of conventional viral and bacterial cultures was 25.6%, which increased to 77.77% after combining with the two multiplex PCR methods. Adenovirus and enterovirus were the most common viral etiologies identified (26.5% of cases) and Streptococcus pneumoniae was the leading bacterial etiology (46.4%). The seasonal trend of viral infections in Southern Taiwan was different from Northern Taiwan. There were no differences in demographic data, severity of disease, or hospital stay between single and mixed infections. A similar result was found between nonpneumococcal and pneumococcal infections.

CONCLUSION

Viral infections were the main etiologies of LRTIs in young children. Multiplex PCR methods are rapid assays that can increase the diagnostic yield rate. Mixed infections do not seem to affect the severity of disease. Early detection may aid clinicians in appropriate decision-making and treatment.

Epidemiological and virological characteristics of influenza viruses circulating in Cambodia from 2009 to 2011

BACKGROUND

The Cambodian National Influenza Center (NIC) monitored and characterized circulating influenza strains from 2009 to 2011.

METHODOLOGY/PRINCIPAL FINDINGS

Sentinel and study sites collected nasopharyngeal specimens for diagnostic detection, virus isolation, antigenic characterization, sequencing and antiviral susceptibility analysis from patients who fulfilled case definitions for influenza-like illness, acute lower respiratory infections and event-based surveillance. Each year in Cambodia, influenza viruses were detected mainly from June to November, during the rainy season. Antigenic analysis show that A/H1N1pdm09 isolates belonged to the A/California/7/2009-like group. Circulating A/H3N2 strains were A/Brisbane/10/2007-like in 2009 before drifting to A/Perth/16/2009-like in 2010 and 2011. The Cambodian influenza B isolates from 2009 to 2011 all belonged to the B/Victoria lineage represented by the vaccine strains B/Brisbane/60/2008 and B/Malaysia/2506/2004. Sequences of the M2 gene obtained from representative 2009-2011 A/H3N2 and A/H1N1pdm09 strains all contained the S31N mutation associated with adamantanes resistance except for one A/H1N1pdm09 strain isolated in 2011 that lacked this mutation. No reduction in the susceptibility to neuraminidase inhibitors was observed among the influenza viruses circulating from 2009 to 2011. Phylogenetic analysis revealed that A/H3N2 strains clustered each year to a distinct group while most A/H1N1pdm09 isolates belonged to the S203T clade.

CONCLUSIONS/SIGNIFICANCE

In Cambodia, from 2009 to 2011, influenza activity occurred throughout the year with peak seasonality during the rainy season from June to November. Seasonal influenza epidemics were due to multiple genetically distinct viruses, even though all of the isolates were antigenically similar to the reference vaccine strains. The drug susceptibility profile of Cambodian influenza strains revealed that neuraminidase inhibitors would be the drug of choice for influenza treatment and chemoprophylaxis in Cambodia, as adamantanes are no longer expected to be effective.

Prolonged seasonality of respiratory syncytial virus infection among preterm infants in a subtropical climate

Objective

There is limited epidemiological data on the seasonality of respiratory syncytial virus (RSV) infection in subtropical climates, such as in Taiwan. This study aimed to assess RSV seasonality among children ≤24 months of age in Taiwan. We also assessed factors (gestational age [GA], chronologic age [CA], and bronchopulmonary dysplasia [BPD]) associated with RSV-associated hospitalization in preterm infants to confirm the appropriateness of the novel Taiwanese RSV prophylactic policy.

Study Design

From January 2000 to August 2010, 3572 children aged ≤24-months were admitted to Taipei Mackay Memorial Hospital due to RSV infection. The monthly RSV-associated hospitalization rate among children aged ≤24 months was retrospectively reviewed. Among these children, 378 were born preterm. The associations between GA, CA, and BPD and the incidence of RSV-associated hospitalization in the preterm infants were assessed.

Results

In children aged ≤24 months, the monthly distribution of RSV-associated hospitalization rates revealed a prolonged RSV season with a duration of 10 months. Infants with GAs ≤32 weeks and those who had BPD had the highest rates of RSV hospitalization (P<0.001). Preterm infants were most vulnerable to RSV infection within CA 9 months.

Conclusions

Given that Taiwan has a prolonged (10-month) RSV season, the American Academy of Pediatrics' recommendations for RSV prophylaxis are not directly applicable. The current Taiwanese guidelines for RSV prophylaxis, which specify palivizumab injection (a total six doses until CA 8–9 months) for preterm infants (those born before 28^6/7 weeks GA or before 35^6/7 weeks GA with BPD), are appropriate. This prophylaxis strategy may be applicable to other countries/regions with subtropical climates.

Epidemiological and clinical evaluation of children with respiratory virus infections

BACKGROUND

Respiratory viruses are the leading cause of respiratory tract infections among children and are responsible for causing morbidity and mortality worldwide. This study was performed to detect viruses in children with respiratory infections and describe their epidemiology and clinical characteristics.

METHODS

In this descriptive cross sectional study, throat swabs and wash specimens from 202 children younger than six years of age with diagnosis of a respiratory tract infection from a total of 897 specimens were evaluated using multiplex PCR method.

RESULTS

Respiratory viruses were detected in 92 children: respiratory synsytial virus, 16.8%; influenza virus, 5.4%; parainfluenza virus, 8.4%; adenovirus, 14.4% and human metapneumo virus 0.49% with male predominance and higher distribution in children younger than 1 year of age with preference in the cold months of year. The clinical presentations of all detected viruses were almost similar.

CONCLUSION

In the present study, nine different respiratory viruses were detected. RSV causes the great majority of respiratory virus infections in children. There was no significant difference in epidemiologic patterns of these viruses in comparison to other studies.

A novel six consecutive monthly doses of palivizumab prophylaxis protocol for the prevention of respiratory syncytial virus infection in high-risk preterm infants in Taiwan

BACKGROUND

Respiratory syncytial virus (RSV) circulates year round in Taiwan. A novel six consecutive monthly doses of palivizumab for RSV prevention protocol has been approved for high risk preterm infants since December 2010. This study aimed to determine the clinical effectiveness and safety of this novel protocol for the prevention of RSV infection.

METHODS

From April 2011 to March 2013, we enrolled infants born at ≤28 weeks gestation and infants born at ≤35 weeks gestation with chronic lung disease (CLD) who received palivizumab prophylaxis as study group and followed up for 12 months. Historic control, those who were born and followed up between July 2000 and June 2008, were retrieved for propensity score matching. Primary endpoint was RSV-related hospitalization, and secondary endpoints included the length of hospital stay and intensive care unit (ICU) care.

RESULTS

We enrolled 127 infants (108 infants born at ≤28 weeks and 19 infants born at 29-35 weeks with CLD). They completed 6-dose palivizumab as scheduled. Among the study group, the RSV-related hospitalizations were 2 (1.6%) within 6 months and 5 (3.9%) within 12 months after discharge. We matched 127 infants in the control group with 127 infants in the study group by propensity score matching. The reduction of RSV-related hospitalization rates were 86% (10.2% vs 1.6%, p = 0.002) within 6 months after discharge and 78% (15.7% vs 3.9%, p = 0.004) within 12 months after discharge. Compared to the control group, the rate of ICU care significantly decreased from 7.1% to 0.8% (p = 0.024) within 6 months after discharge and from 7.9% to 0.8% (p = 0.014) within 12 months after discharge. Adverse events were recorded in 6.4% injections.

CONCLUSIONS

Six monthly intramuscular administration of palivizumab is effective for prevention of RSV hospitalization in regions with no single seasonal peak of RSV infection such as Taiwan.

Clinical features of coxsackievirus A4, B3 and B4 infections in children

Background

Clinical features of coxsackievirus A4 (CA4), B3 (CB3) and B4 (CB4) infections in children have not been comprehensively described.

Methods/Principal Findings

From January 2004 to June 2012, a total of 386 children with culture-proven CA4, CB3 and CB4 infections treated at Chang Gung Memorial Hospital, including 296 inpatients (CA4, 103; CB3, 131; CB4, 62) and 90 outpatients (CA4, 55; CB3, 14; CB4, 21), were included. From outpatients, only demographics were extracted and from inpatients, detailed clinical and laboratory data were collected retrospectively. The mean age was 32.1±30.2 months; male to female ratio was 1.3∶1. Children with CB3 infection were youngest (76.6% <3 years of age), and had a highest hospitalization rate (90.3%) and a longest duration of hospitalization (mean ± SD, 7.5±6.2 days). Herpangina (74.8%) was the most common presentation for children with CA4 infection, aseptic meningitis (26.7%) and young infant with fever (23.7%) for those with CB3 infection, and herpangina (32.3%) and tonsillitis/pharyngitis (27.4%) for children with CB4 infection. Almost all the inpatients had fever (97.6%). Twelve out of thirteen (92.3%) children with complications and ten of 11 children with long-term sequelae had CB3 infections. Two fatal cases were noted, one due to myocarditis with CA4 infection and CB3 were detected from the other case which had hepatic necrosis with coagulopathy. The remaining 285 children (96.3%) recovered uneventfully.

Conclusion

CA4, CB3 and CB4 infections in children had different clinical disease spectrums and involved different age groups. Though rare, severe diseases may occur, particularly caused by CB3.

Human parainfluenza virus in patients with influenza-like illness from Central and South America during 2006-2010

Background

Human parainfluenza viruses (HPIVs) are common viral causes of community-acquired pneumonia, particularly in children. The four types of HPIV have world-wide distribution; however, limited information exists about the epidemiological profile of HPIV in Latin-America.

Objective

Provide epidemiologic and phylogenetic information about HPIVs that circulated in Latin America between 2006 and 2010 to better characterize the extent and variability of this respiratory virus in the region.

Methods

Oropharyngeal swabs, demographic data and clinical characteristics were obtained from individuals with influenza-like illness in 10 Latin-American countries between 2006–2010. Specimens were analyzed with culture and molecular methods.

Results

A total of 30 561 individuals were enrolled; 991 (3·2%) were HPIV positive. Most infected participants were male (53·7%) and under 5 years of age (68·7%). The HPIV type most frequently isolated was HPIV-3 (403, 40·7%). In 66/2007 (3·3%) hospitalized individuals, HPIV was identified. The most frequent symptoms at enrollment were cough and rhinorrhea. We identified certain patterns for HPIV-1, -2 and -3 in specific cities. Phylogenetic analysis revealed a homogeneous distribution in the region.

Conclusions

In the current scenario, no vaccine or treatment is available for this pathogen. Our results contribute to the scarce epidemiologic and phylogenetic information of HPIV in the region that could support the development of specific management.

Human rhinoviruses and enteroviruses in influenza-like illness in Latin America

Background

Human rhinoviruses (HRVs) belong to the Picornaviridae family with high similarity to human enteroviruses (HEVs). Limited data is available from Latin America regarding the clinical presentation and strains of these viruses in respiratory disease.

Methods

We collected nasopharyngeal swabs at clinics located in eight Latin American countries from 3,375 subjects aged 25 years or younger who presented with influenza-like illness.

Results

Our subjects had a median age of 3 years and a 1.2:1.0 male:female ratio. HRV was identified in 16% and HEV was identified in 3%. HRVs accounted for a higher frequency of isolates in those of younger age, in particular children < 1 years old. HRV-C accounted for 38% of all HRVs detected. Phylogenetic analysis revealed a high proportion of recombinant strains between HRV-A/HRV-C and between HEV-A/HEV-B. In addition, both EV-D68 and EV-A71 were identified.

Conclusions

In Latin America as in other regions, HRVs and HEVs account for a substantial proportion of respiratory viruses identified in young people with ILI, a finding that provides additional support for the development of pharmaceuticals and vaccines targeting these pathogens.

High-incidence of human adenoviral co-infections in taiwan

Background

Respiratory infections caused by adenovirus (HAdV) are common year round. Recently, a significant increase of adenoviral infections was observed in Taiwan.

Objective

To understand the prevalence and molecular epidemiology of respiratory adenovirus circulating in Taiwan for the past decade.

Study Design

One hundred and twenty-six human adenoviruses, isolated between 2002 to 2011, were characterized via DNA sequencing of the hexon and fiber genes. The nucleotide sequences were then compared by phylogenetic analysis.

Results

HAdV-B3 accounted for 64.3% (81/126) and peaked almost every year, whereas the sequences of hexon and fiber genes of HAdV-B3 were highly conserved in different years. A high incidence of co-infection of adenoviruses was observed (19.0%, 24/126); HAdV-B3 co-infected with HAdV-C2 was the most common combination (58.3%, 14/24). An additional interesting finding of repeated infection was noted in 10 children, all of whom showed first infection with adenovirus species HAdV-C, followed by species HAdV-B or HAdV-E.

Conclusions

HAdV-B3 was the predominant type of respiratory adenovirus circulating in Taiwan over the past ten years. This merits further attention for vaccine development. Furthermore, the observed high-incidence of adenoviral co-infections along with repeated infections found in our study provides important epidemiological insights into adenovirus infections.

The epidemiology of hospitalization for pneumonia in children under five in the rural western region of Nepal: a descriptive study

Pneumonia is one of the major public health problems in children under five years of age. The aim of this study was to analyze the time, place, and characteristics of the distribution of pneumonia in hospitalized children under five years of age at the Dhaulagiri Zonal Hospital (DZH) in Nepal. A descriptive cross-sectional study was carried out at DZH from July 16, 2008 to August 17, 2011 for hospitalized children under five years of age and diagnosed with pneumonia. The main bacterial cause of pneumonia was Streptococcus pneumoniae and the main viral cause was Respiratory Syntical Virus (RSV). The majority of children admitted for treatment of pneumonia were males (60%), from upper class ethnic groups, and common among those aged 29 days to one year (49.1% of overall pneumonia cases). Data from this study show that pneumonia episodes in DZH occurred throughout the year with a sharp increase in the occurrence at the end of August to September. More cases were recorded during the rainy seasons and winter months in all three study years. The cases were from households most concentrated in Baglung municipality where the hospital is located. Pneumonia was found in higher proportions among hospitalized male children, those aged 29 days to one year, and in upper ethnic groups, during the rainy seasons and in winter months, and among local populations near the hospital in the rural western region of Nepal. Strengthening community-based case management, prevention strategies, and health care delivery system would help reduce pneumonia cases and the overall burden associated with it.

Latitudinal variations in seasonal activity of influenza and respiratory syncytial virus (RSV): a global comparative review

BACKGROUND

There is limited information on influenza and respiratory syncytial virus (RSV) seasonal patterns in tropical areas, although there is renewed interest in understanding the seasonal drivers of respiratory viruses.

METHODS

We review geographic variations in seasonality of laboratory-confirmed influenza and RSV epidemics in 137 global locations based on literature review and electronic sources. We assessed peak timing and epidemic duration and explored their association with geography and study settings. We fitted time series model to weekly national data available from the WHO influenza surveillance system (FluNet) to further characterize seasonal parameters.

RESULTS

Influenza and RSV activity consistently peaked during winter months in temperate locales, while there was greater diversity in the tropics. Several temperate locations experienced semi-annual influenza activity with peaks occurring in winter and summer. Semi-annual activity was relatively common in tropical areas of Southeast Asia for both viruses. Biennial cycles of RSV activity were identified in Northern Europe. Both viruses exhibited weak latitudinal gradients in the timing of epidemics by hemisphere, with peak timing occurring later in the calendar year with increasing latitude (P<0.03). Time series model applied to influenza data from 85 countries confirmed the presence of latitudinal gradients in timing, duration, seasonal amplitude, and between-year variability of epidemics. Overall, 80% of tropical locations experienced distinct RSV seasons lasting 6 months or less, while the percentage was 50% for influenza.

CONCLUSION

Our review combining literature and electronic data sources suggests that a large fraction of tropical locations experience focused seasons of respiratory virus activity in individual years. Information on seasonal patterns remains limited in large undersampled regions, included Africa and Central America. Future studies should attempt to link the observed latitudinal gradients in seasonality of viral epidemics with climatic and population factors, and explore regional differences in disease transmission dynamics and attack rates.

Differential expression of coxsackievirus and adenovirus receptor on alveolar epithelial cells between fetal and adult mice determines their different susceptibility to coxsackievirus B infection

Coxsackievirus B (CVB) can cause aseptic meningitis, myocarditis and respiratory disease, especially in newborn infants. To compare the susceptibility to CVB infection of fetal and adult mice, we prepared primary alveolar epithelial cells (AECs) from lungs of BALB/c mice. In contrast to fetal mouse AECs, those of adults were less susceptible to CVB3 infection, as indicated by decreased cytopathic effects, and reduced levels of viral particles bound at the cell surface. In adult mouse AECs, amplification of the viral genome and virus capsid protein VP1 synthesis were concomitantly reduced. In addition, the cell-surface expression of coxsackievirus and adenovirus receptor (CAR), which plays a key role in the initiation of CVB and pulmonary infection, was downregulated in adult mouse AECs. These findings demonstrate that adult mouse AECs are less susceptible to CVB3 due to decreased CAR levels. Thus, these findings strongly indicate that the level of virus receptors on AECs is one of the crucial determinants for the age-dependence of CVB virulence in the mouse lung.

Incidence of respiratory virus-associated pneumonia in urban poor young children of Dhaka, Bangladesh, 2009-2011

BACKGROUND

Pneumonia is the leading cause of childhood death in Bangladesh. We conducted a longitudinal study to estimate the incidence of virus-associated pneumonia in children aged <2 years in a low-income urban community in Dhaka, Bangladesh.

METHODS

We followed a cohort of children for two years. We collected nasal washes when children presented with respiratory symptoms. Study physicians diagnosed children with cough and age-specific tachypnea and positive lung findings as pneumonia case-patients. We tested respiratory samples for respiratory syncytial virus (RSV), rhinoviruses, human metapneumovirus (HMPV), influenza viruses, human parainfluenza viruses (HPIV 1, 2, 3), and adenoviruses using real-time reverse transcription polymerase chain reaction assays.

RESULTS

Between April 2009-March 2011, we followed 515 children for 730 child-years. We identified a total of 378 pneumonia episodes, 77% of the episodes were associated with a respiratory viral pathogen. The overall incidence of pneumonia associated with a respiratory virus infection was 40/100 child-years. The annual incidence of pneumonia/100 child-years associated with a specific respiratory virus in children aged < 2 years was 12.5 for RSV, 6 for rhinoviruses, 6 for HMPV, 4 for influenza viruses, 3 for HPIV and 2 for adenoviruses.

CONCLUSION

Young children in Dhaka are at high risk of childhood pneumonia and the majority of these episodes are associated with viral pathogens. Developing effective low-cost strategies for prevention are a high priority.

Evaluation of a streptococcal pharyngitis score in southern Taiwan

BACKGROUND

Group A streptococcus (GAS) pharyngitis can cause serious complications such as rheumatic heart disease. The McIsaac sore throat score is a clinical prediction score used to improve the detection rate of GAS pharyngitis. We evaluated the validity of the McIsaac sore throat score in Southern Taiwan and compared our findings to those of other studies.

METHODS

We retrospectively analyzed chart records from children aged 3 to 15 years old who complained of fever and sore throat. They had throat cultures collected at the outpatient pediatric clinic of Fooyin University Hospital, located in Pingtung County, Taiwan during the period between January 2007 and January 2010. Clinical characteristics were reviewed, and sore throat score was analyzed.

RESULTS

A total of 342 throat cultures met the inclusion criteria of sore throat and fever. The positive rate of GAS was 4.1%. Culture-positive cases were associated with higher odds for a skin rash [adjusted odds ratio (AOR): 14.66, 95% confidence interval (CI): 4.63-46.40, p < 0.001), lower odds for cough (AOR: 0.19, 95% CI: 0.04-0.85, p = 0.030) and having a runny nose (AOR: 0.22, 95% CI: 0.05-0.99, p = 0.048). The most common physical sign was scarlet fever rash (AOR: 57.35, 95% CI: 15.45-212.98, p < 0.001). A McIsaac score of 5 had a sensitivity of 71%, specificity of 70%, and a positive predictive value of only 9.3%.

CONCLUSION

Pediatric streptococcal pharyngitis in Southern Taiwan is uncommon. Diagnosis of GAS pharyngitis based on the McIsaac sore throat score is unreliable among pediatric patients with febrile pharyngitis in Southern Taiwan.

Aetiology of upper respiratory tract infections in children in Arak city: a community based study

Viruses are frequent causes of upper respiratory tract infections in children. We investigated the viral aetiology of community-acquired upper respiratory tract infections (URIs) in young children treated as outpatients in community settings. During November 2008, nasal swab specimens were taken from children with recent onset of upper respiratory tract infections. The patients attended day care or primary schools; the specimens were randomly obtained by pediatricians from schools and childcare institutions and sent for identification by PCR method. A total of 300 specimens were collected. From all samples, 40.67% were positive for at least 1 virus, viz. adenovirus 11.76%, rhinovirus 9.8%, respiratory syncytial virus 6.08%, influenza virus 5.56%, parainfluenza virus 4.9%, enterovirus 2.94% and a combination of 2 viruses 2%. Clinical manifestations of the respiratory infections were as follows: 70.7% of the patients had coryza, 69.3% cough, 26% sneezing, 19.7% sore throat, 2.7% headache, 7.7% fever, 2.3% conjunctivitis, 1.3% abdominal pain and 1% hoarseness. The results of this study demonstrate that adenoviruses and rhinoviruses are the two most common viral agents isolated from pediatric outpatients with acute URIs in autumn in Arak City. Coryza and cough were the most common symptoms in children. Sore throat and hoarseness were more prevalent in infections caused by influenza virus, conjunctivitis in parainfluenza, and coryza in rhinovirus infections.