Seasonality of distinct respiratory viruses in a tropical city: implications for prophylaxis.

OBJECTIVE: The frequency and seasonality of viruses in tropical regions are scarcely reported. We estimated the frequency of seven respiratory viruses and assessed seasonality of respiratory syncytial virus (RSV) and influenza viruses in a tropical city. METHODS: Children (age ≤ 18 years) with acute respiratory infection were investigated in Salvador, Brazil, between July 2014 and June 2017. Respiratory viruses were searched by direct immunofluorescence and real-time polymerase chain reaction for detection of RSV, influenza A virus, influenza B virus, adenovirus (ADV) and parainfluenza viruses (PIV) 1, 2 and 3. Seasonal distribution was evaluated by Prais-Winsten regression. Due to similar distribution, influenza A and influenza B viruses were grouped to analyse seasonality. RESULTS: The study group comprised 387 cases whose median (IQR) age was 26.4 (10.5-50.1) months. Respiratory viruses were detected in 106 (27.4%) cases. RSV (n = 76; 19.6%), influenza A virus (n = 11; 2.8%), influenza B virus (n = 7; 1.8%), ADV (n = 5; 1.3%), PIV 1 (n = 5; 1.3%), PIV 3 (n = 3; 0.8%) and PIV 2 (n = 1; 0.3%) were identified. Monthly count of RSV cases demonstrated seasonal distribution (b3 = 0.626; P = 0.003). More than half (42/76 [55.3%]) of all RSV cases were detected from April to June. Monthly count of influenza cases also showed seasonal distribution (b3 = -0.264; P = 0.032). Influenza cases peaked from November to January with 44.4% (8/18) of all influenza cases. CONCLUSIONS: RSV was the most frequently detected virus. RSV and influenza viruses showed seasonal distribution. These data may be useful to plan the best time to carry out prophylaxis and to increase the number of hospital beds.

Neurogenic pulmonary edema following febrile status epilepticus in a 22-month-old infant with multiple respiratory virus co-detection: a case report.

BACKGROUND: Neurogenic pulmonary edema is a rare but serious complication of febrile status epilepticus in children. Comprehensive screening for viral pathogens is seldomly performed in the work-up of febrile children. CASE PRESENTATION: A 22-month-old girl presented with her first episode of febrile status epilepticus, after which she developed acute pulmonary edema and respiratory failure. After the termination of seizure activity, the patient was intubated and managed on mechanical ventilation in the emergency room. The resolution of respiratory failure, as well as the neurological recovery, was achieved 9 h after admission, and the patient was discharged 6 days after admission without any complications. Molecular biological diagnostic methods identified the presence of human coronavirus HKU1, influenza C virus, and human parainfluenza virus 2 from the patient's nasopharyngeal specimens. CONCLUSIONS: Neurogenic pulmonary edema following febrile status epilepticus was suspected to be the etiology of our patient's acute pulmonary edema and respiratory failure. Timely seizure termination and rapid airway and respiratory intervention resulted in favorable outcomes of the patient. Molecular biological diagnostic methods identified three respiratory viruses; however, their relevance and association with clinical symptoms remain speculative.

Changes in the etiology of viral lower respiratory tract infections in hospitalized children in Wenzhou, China: 2008-2017.

This study investigated the seasonality and secular trends in the etiology of viral lower respiratory tract infections (LRTIs) among hospitalized children in Wenzhou, southeastern China. A retrospective review was conducted concerning viral LRTIs in children hospitalized at a university hospital between January 1, 2008 and December 31, 2017. Direct immunofluorescence was used to detect respiratory syncytial virus (RSV), adenovirus (AdV), influenza A virus (Inf A), influenza B virus (Inf B), and human parainfluenza virus types 1 to 3 (hPIV1-3). Of 89 898 children tested, at least one viral respiratory pathogen was identified in 25.6% and multiple pathogens were identified in 0.4%. RSV (17.6%), hPIV3 (4.0%), and AdV (2.2%) were the most frequently detected pathogens. The proportion of positive samples varied with age and was the highest in children aged <6 months (36.2%). Seasonal differences were observed in RSV, AdV, Inf A, Inf B, hPIV1, and hPIV3 infections. There was a declining trend in the proportion of positive samples over time, primarily due to a decrease in RSV and hPIV3 infections. RSV, hPIV3, and AdV were the most common viral respiratory pathogens identified among hospitalized children with LRTIs. The distribution of viruses varied with age and season.

Characteristics of human parainfluenza virus type 4 infection in hospitalized children in Korea.

BACKGROUND: The characteristics of human parainfluenza virus type 4 (hPIV4) infection are not thoroughly understood. We therefore clarified the characteristics of hPIV4 in Korea. METHOD: From January 2013 to December 2017, children admitted with respiratory tract infection at the Department of Pediatrics in Chung-Ang University Hospital were enrolled in the study. Nasopharyngeal aspirate specimens were obtained from patients and tested for hPIV types by multiplex reverse transcription polymerase chain reaction. We retrospectively reviewed subject medical records, focusing on epidemiological and clinical characteristics. RESULTS: Of the 12 423 NPA specimens, 8,406 were positive by multiplex reverse transcription polymerase chain reaction for nine respiratory viruses, and 1,018 were positive for one of the four types of hPIV: 1,018 specimens led to the detection of 1,029 hPIVs; 3ss (31.3%) were positive for hPIV1, 120 (11.7%) were positive for hPIV2, 356 (34.6%) were positive for hPIV3, and 231 (22.4%) were positive for hPIV4. Of the hPIV-positive patients, the mean age was 2.3 years (range, 0.1-12.7 years), 225 (97.4%) had no underlying disease, and 178 (77.1%) had a fever with a duration of 4.1 ± 2.3 days and a peak temperature of 39.0 ± 0.7 ℃. The most common diagnosis in hPIV4 infection was pneumonia (44.2%), followed by bronchiolitis (26.0%) and upper respiratory tract infection (24.3%). Only 2.2% of patients were diagnosed with croup. Although the most prevalent overall type of hPIV was hPIV3, hPIV4 generally caused acute respiratory tract infection in summer and early fall in an irregular annual pattern. CONCLUSIONS: Human parainfluenza virus type 4 is an important common pathogen of respiratory tract infections in pediatric patients in Korea.

Using routine testing data to understand circulation patterns of influenza A, respiratory syncytial virus and other respiratory viruses in Victoria, Australia.

Several studies have reported evidence of interference between respiratory viruses: respiratory viruses rarely reach their epidemic peak concurrently and there appears to be a negative association between infection with one respiratory virus and co-infection with another. We used results spanning 16 years (2002-2017) of a routine diagnostic multiplex panel that tests for nine respiratory viruses to further investigate these interactions in Victoria, Australia. Time series analyses were used to plot the proportion positive for each virus. The seasonality of all viruses included was compared with respiratory syncytial virus (RSV) and influenza A virus using cross-correlations. Logistic regression was used to explore the likelihood of co-infection with one virus given infection with another. Seasonal peaks were observed each year for influenza A and RSV and less frequently for influenza B, coronavirus and parainfluenza virus. RSV circulated an average of 6 weeks before influenza A. Co-infection with another respiratory virus was less common with picornavirus, RSV or influenza A infection. Our findings provide further evidence of a temporal relationship in the circulation of respiratory viruses. A greater understanding of the interaction between respiratory viruses may enable better prediction of the timing and magnitude of respiratory virus epidemics.

A 28-year study of human parainfluenza in Rio Grande do Sul, Southern Brazil.

PROBLEM: Human parainfluenza virus (hPIV) is an important pathogen in respiratory infections, however the health burden of hPIV is underestimated. This study describes the infections by hPIV1-3 in Rio Grande do Sul, Brazil, from 1990 to 2017, providing data of the frequency and seasonality of cases and associated clinical symptoms. METHOD OF STUDY: Nasopharyngeal samples of patients with respiratory infection were collected, clinical data were analyzed, and immunofluorescence was used to detect hPIV. RESULTS: Respiratory viruses were detected in 33.63% of respiratory infections. In a total of 11 606 cases of viral respiratory infection, 781 were positive for hPIV; hPIV prevalence ranged from 2.14% to 27% of viral respiratory infections. hPIV1 circulates mainly during fall; hPIV3 circulation, in turn, starts in fall and peaks during spring; and cases of hPIV2 are reported along the year, with peaks in fall and early spring. The most affected age group was children, with hPIV prevalence of 74.23% in patients for less than 1 year. A higher proportion of girls were infected than boys, however, no difference by sex was observed considering all age groups. The most frequent type was hPIV3, especially in hospitalized patients. Both hPIV1 and 3 were associated with dyspnea, while hPIV2 caused mild symptoms mainly in nonhospitalized patients. Nineteen fatalities occurred, 89.5% of them associated with risk factors (prematurity; chronic diseases; age, <1 or >60 years). CONCLUSION: hPIV causes a high number of respiratory infections, leading to hospitalization especially in children; epidemiological and surveillance studies are important for the control and management of respiratory infections.

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.

HUMAN PARAINFLUENZA 2 RELATED ILLNESS AND A DEATH IN A GROUP OF CAPTIVE WESTERN LOWLAND GORILLAS (GORILLA GORILLA GORILLA).

An onset of respiratory disease in a captive bachelor group (n = 3) of western lowland gorillas (Gorilla gorilla gorilla) was concomitant with peak attendance of visitors at the institution and with unwanted occurrences of food items being thrown in the gorillas' enclosure. While the condition of two individuals improved with supportive therapy and antibiotics, the third gorilla died three days following initiation of treatment. A fatal bacterial pneumonia, secondary to an infection by a human parainfluenza virus 2 (HIPV-2), was considered to be the cause of death based on histopathology, lung cultures, and reverse transcription PCR. HPIV-2 activity in the human population of the province was detected for that period, including the same viral strain. This report confirms a HPIV-2 respiratory illness and associated death in a gorilla. Clinical presentation and context suggest conspecifics were also affected and that contaminated food thrown by visitors may have been the source of infection.

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.

Infants hospitalized for Bordetella pertussis infection commonly have respiratory viral coinfections.

BACKGROUND: Whether viral coinfections cause more severe disease than Bordetella pertussis (B. pertussis) alone remains unclear. We compared clinical disease severity and sought clinical and demographic differences between infants with B. pertussis infection alone and those with respiratory viral coinfections. We also analyzed how respiratory infections were distributed during the 2 years study. METHODS: We enrolled 53 infants with pertussis younger than 180 days (median age 58 days, range 17­109 days, 64. 1% boys), hospitalized in the Pediatric Departments at "Sapienza" University Rome and Bambino Gesù Children's Hospital from August 2012 to November 2014. We tested in naso-pharyngeal washings B. pertussis and 14 respiratory viruses with real-time reverse-transcriptase-polymerase chain reaction. Clinical data were obtained from hospital records and demographic characteristics collected using a structured questionnaire. RESULTS: 28/53 infants had B. pertussis alone and 25 viral coinfection: 10 human rhinovirus (9 alone and 1 in coinfection with parainfluenza virus), 3 human coronavirus, 2 respiratory syncytial virus. No differences were observed in clinical disease severity between infants with B. pertussis infection alone and those with coinfections. Infants with B. pertussis alone were younger than infants with coinfections, and less often breastfeed at admission. CONCLUSIONS: In this descriptive study, no associations between clinical severity and pertussis with or without co-infections were found. TRIAL REGISTRATION: Policlinico Umberto I: protocol 213/14, 3085/13.02.2014, retrospectively registered. Bambino Gesù Children's Hospital: protocol n. RF-2010-2317709.

Use of laboratory and administrative data to understand the potential impact of human parainfluenza virus 4 on cases of bronchiolitis, croup, and pneumonia in Alberta, Canada.

BACKGROUND: Human Parainfluenza Virus (hPIV) causes severe respiratory illness in infants and adults. Our study describes the association of hPIV1-4 with bronchiolitis, croup, and pneumonia using retrospective laboratory, administrative and public health data. Due to issues including the historic lack of hPIV4 in some commercial respiratory virus panels, the description of the impact of hPIV4 on croup, bronchiolitis, and pneumonia at population levels has often been limited. This study will use routine clinical laboratory data, and administrative data to provide a preliminary description of the impact of hPIV4 on these diseases in our population. METHODS: A three year cohort of patients positive for hPIV was linked with data from physician visits and hospital admissions to define cases and hospitalization status. International Classification of Disease (ICD-9) codes were used to determine if cases had croup, bronchiolitis, and pneumonia. We also looked at differences in hospitalization status, age and gender among hPIV1-4. All statistical analysis was done using SPSS (Version 19.0.0, IBM Corp© 2010) and Graphpad Prism V6 (GraphPad Software, Inc., 2012). RESULTS: Only hPIV1 and hPIV4 specimens had positivity rates greater than 5 % of all specimens sent for respiratory virus panel testing. hPIV1 exhibited a biennial pattern while the pattern for hPIV3 was less interpretable due to lower positivity rates. Circulation patterns for hPIV2 and hPIV4 were not assessed due to the low positivity rates of theses specimens. From 2010 to 2013, there were 2300 hPIV cases with hPIV3 (46 %) being the most common, followed by hPIV1 (27 %), hPIV4 (16 %) and hPIV2 (11 %). The median age was 2 years for all hPIV types. Males were slightly greater than females for hPIV1 and hPIV2, with an equal distribution for hPIV3 and slightly more females than males for hPIV4. hPIV1 and hPIV2 had the highest or proportion of croup while hPIV3 and hPIV4 had the highest proportion of pneumonia. Within hPIV4 cases, distributions of diseases were; pneumonia (21 %, 95 % CI 17.1-25.7), bronchiolitis (18 %, 95 % CI 14.3-22.5), croup (2 %, 95 % CI 0.8-3.9), mixed illness of any of pneumonia, bronchiolitis or croup (4 %, 95 % CI 2.5-7.0) or other respiratory diseases (54 %, 95 % CI 49.1-59.6). CONCLUSIONS: We used laboratory and administrative data to undertake a descriptive analysis of the association of hPIV1-4 with croup, bronchiolitis and pneumonia. hPIV4 appears to be more associated more with bronchiolitis and pneumonia and less with croup in our population.

Human parainfluenza virus types 1-4 in hospitalized children with acute lower respiratory infections in China.

Human parainfluenza viruses (HPIVs) are an important cause of acute lower respiratory tract infections (ALRTIs). HPIV-4, a newly identified virus, has been associated with severe ALRTIs recently. A total of 771 nasopharyngeal aspirate samples were collected from hospitalized children between March 2010 and February 2011. HPIVs were detected by Nest-PCR, and other known respiratory viruses were detected by RT-PCR and PCR. All amplification products were sequenced. HPIVs were detected in 151 (19.58%) patients, of whom 28 (3.63%) were positive for HPIV-4, 12(1.55%) for HPIV-1, 4 (0.51%) for HPIV-2, and 107 (13.87%) for HPIV-3. Only three were found to be co-infected with different types of HPIVs. All HPIV-positive children were under 5 years of age, with the majority being less than 1 year. Only the detection rate of HPIV-3 had a significant statistical difference (χ2 = 29.648, P = 0.000) between ages. HPIV-3 and HPIV-4 were detected during the summer. Sixty (39.74%) were co-infected with other respiratory viruses, and human rhinovirus (HRV) was the most common co-infecting virus. The most frequent clinical diagnosis was bronchopneumonia, and all patients had cough; some patients who were infected with HPIV-3 and HPIV-4 had polypnea and cyanosis. No significant difference was found in clinical manifestations between those who were infected with HPIV-4 and HPIV-3. Two genotypes for HPIV-4 were prevalent, although HPIV-4a dominated. HPIV-4 is an important virus for children hospitalized with ALRTIs in China. HRV was the most common co-infecting virus. Two genotypes for HPIV-4 are prevalent, HPIV-4a dominated. J. Med. Virol. 88:2085-2091, 2016. © 2016 Wiley Periodicals, Inc.

Genetic diversity among human parainfluenza virus type 2 isolated in Croatia between 2011 and 2014.

The dynamics and evolution of the human parainfluenza virus type 2 (HPIV2) in Croatia, and also globally, are largely unknown. Most HPIV2 infections are treated symptomatically outside the hospital setting. Thus, the diagnosis is missing making it difficult to follow the genetic variation and evolution of the HPIV2. This study explores hospitalized HPIV2 cases in Croatia during 4-year period (2011-2014). Most cases in this period were reported in October or November (68.75%) and most of patients were under 2 years of age (81.25%). For molecular analyses, we used the F and HN gene sequences and showed that although both regions are equally suitable for phylogenetic analyses it would be advantageous to use regions longer than 2 kb for HPIV2 analyses of isolates which are spatially and temporally closely related. We show here that the dominant cluster in this area was cluster G3 while only one strain isolated in this period was positioned in the distant cluster G1a. Further monitoring of the HPIV2 will determine whether cluster G3 will remain dominant or it will be overruled by cluster G1a. This will be important for the surveillance of virus circulation in population and significance of the viral infection. J. Med. Virol. 88:1733-1741, 2016. © 2016 Wiley Periodicals, Inc.

Child homicide or natural death? A case report of unexpected death of unusual asymptomatic acute laryngotracheobronchitis.

Cases involving the unexpected deaths of children are always a concern for the police and medical examiners alike. In particular, unexpected deaths due to asphyxia without obvious injuries sometimes make decisions regarding the manner of death more difficult. In the present case, a 2-year-old boy was found dead at home, and his mother was initially believed to have killed him. A complete autopsy and forensic investigation were performed, and no injuries were found on the body; however, marked laryngeal edema was observed. Histology showed extensive inflammatory infiltration of the mucosa and submucosa of the larynx, trachea, and bronchi. The cause of death was given as respiratory failure due to acute laryngotracheobronchitis; thus, the manner of death was natural. This case helps to remind the forensic community to keep an open mind and consider a broad differential diagnosis when approaching a case rather than jumping to a conclusion based solely on a preliminary investigation.

Isolation & molecular characterization of human parainfluenza virus in Chennai, India.

BACKGROUND & OBJECTIVES: Human parainfluenza virus (HPIV) accounts for a significant proportion of lower respiratory tract infections in children as well as adults. This study was done to detect the presence of different subtypes of HPIV from patients having influenza like illness (ILI). METHODS: Throat and nasal swabs from 232 patients with ILI who were negative for influenza viruses were tested by multiplex reverse transcription polymerase chain reaction(mRT-PCR) for the detection of human parainfluenza virus. All samples were inoculated in rhesus monkey kidney (LLC-MK2) cell line. RESULTS: Of the 232 samples, 26(11.2%) were positive by mRT-PCR and nine (34.6%) showed cytopathic effect with syncytium formation for HPIV and all were HPIV-3 serotype, other serotypes like 1,2,4 were negative. The HPIV-3 strains (HN gene) were sequenced and analysed. Two novel mutations were identified at amino acid residues 295 and 297. INTERPRETATION & CONCLUSIONS: The mRT-PCR assay offers a rapid, sensitive and accurate diagnostic method for detection of HPIV which enables early detection and control. In our study there was a predominance of HPIV among 1-5 yr age group and the school going age group was less affected. Further studies need to be done to characterize HPIV isolated from different parts of the country.

Severe acute respiratory infection in children in a densely populated urban slum in Kenya, 2007-2011.

BACKGROUND: Reducing acute respiratory infection burden in children in Africa remains a major priority and challenge. We analyzed data from population-based infectious disease surveillance for severe acute respiratory illness (SARI) among children <5 years of age in Kibera, a densely populated urban slum in Nairobi, Kenya. METHODS: Surveillance was conducted among a monthly mean of 5,874 (range = 5,778-6,411) children <5 years old in two contiguous villages in Kibera. Participants had free access to the study clinic and their health events and utilization were noted during biweekly home visits. Patients meeting criteria for SARI (WHO-defined severe or very severe pneumonia, or oxygen saturation <90%) from March 1, 2007-February 28, 2011 had blood cultures processed for bacteria, and naso- and oro- pharyngeal swabs collected for quantitative real-time reverse transcription polymerase chain reaction testing for influenza viruses, parainfluenza viruses (PIV), respiratory syncytial virus (RSV), adenovirus, and human metapneumovirus (hMPV). Swabs collected during January 1, 2009 - February 28, 2010 were also tested for rhinoviruses, enterovirus, parechovirus, Mycoplasma pneumoniae, and Legionella species. Swabs were collected for simultaneous testing from a selected group of control-children visiting the clinic without recent respiratory or diarrheal illnesses. RESULTS: SARI overall incidence was 12.4 cases/100 person-years of observation (PYO) and 30.4 cases/100 PYO in infants. When comparing detection frequency in swabs from 815 SARI cases and 115 healthy controls, only RSV and influenza A virus were significantly more frequently detected in cases, although similar trends neared statistical significance for PIV, adenovirus and hMPV. The incidence for RSV was 2.8 cases/100 PYO and for influenza A was 1.0 cases/100 PYO. When considering all PIV, the rate was 1.1 case/100 PYO and the rate per 100 PYO for SARI-associated disease was 1.5 for adenovirus and 0.9 for hMPV. RSV and influenza A and B viruses were estimated to account for 16.2% and 6.7% of SARI cases, respectively; when taken together, PIV, adenovirus, and hMPV may account for >20% additional cases. CONCLUSIONS: Influenza viruses and RSV (and possibly PIV, hMPV and adenoviruses) are important pathogens to consider when developing technologies and formulating strategies to treat and prevent SARI in children.

Incidence of respiratory viruses in Peruvian children with acute respiratory infections.

Acute respiratory infections are responsible for high morbi-mortality in Peruvian children. However, the etiological agents are poorly identified. This study, conducted during the pandemic outbreak of H1N1 influenza in 2009, aims to determine the main etiological agents responsible for acute respiratory infections in children from Lima, Peru. Nasopharyngeal swabs collected from 717 children with acute respiratory infections between January 2009 and December 2010 were analyzed by multiplex RT-PCR for 13 respiratory viruses: influenza A, B, and C virus; parainfluenza virus (PIV) 1, 2, 3, and 4; and human respiratory syncytial virus (RSV) A and B, among others. Samples were also tested with direct fluorescent-antibodies (DFA) for six respiratory viruses. RT-PCR and DFA detected respiratory viruses in 240 (33.5%) and 85 (11.9%) cases, respectively. The most common etiological agents were RSV-A (15.3%), followed by influenza A (4.6%), PIV-1 (3.6%), and PIV-2 (1.8%). The viruses identified by DFA corresponded to RSV (5.9%) and influenza A (1.8%). Therefore, respiratory syncytial viruses (RSV) were found to be the most common etiology of acute respiratory infections. The authors suggest that active surveillance be conducted to identify the causative agents and improve clinical management, especially in the context of possible circulation of pandemic viruses.

Detection of respiratory viruses in gargle specimens of healthy children.

BACKGROUND: Respiratory tract viral infection is one of the most common and important diseases in children. Polymerase chain reaction (PCR) tests are often used to detect viruses in samples, it is difficult to interpret the clinical significance of PCR positivity, which may reflect a past, imminent or active asymptomatic infection due to their high sensitivity. Although single respiratory viruses have been detected in samples from children with symptoms, other respiratory viruses can also be detected simultaneously. However, the clinical importance of these findings for the symptoms is not known. OBJECTIVES: To investigate the prevalence of respiratory viruses among children without any symptoms such as acute respiratory illness and/or fever. STUDY DESIGN: From week twenty-five 2013 to week twenty-six 2014, gargle samples were collected from children once a week and these samples were subjected to real-time PCR to detect respiratory viruses. On each sampling day, we asked the parents about their children's health condition. RESULTS: Among the 286 samples collected, 200 were from asymptomatic children. In the asymptomatic condition, human parechovirus, adenovirus, enterovirus, rhinovirus, coronavirus 229E and HKU1 were observed in 45 episodes. In samples from symptomatic children, parainfluenza viruses, respiratory syncytial virus and coronavirus OC43 were detected in addition to those mentioned above. CONCLUSIONS: Various viruses of different species were detected in the specimens from the children regardless of their health status. It might be speculated that host factors such as the function of the immune system influence the clinical outcome of the infection. However, this needs to be studied further.

Análisis clínico y epidemiológico de las infecciones pediátricas causadas por los virus Parainfluenza tipos 1-4 durante el período 2013-2014 / Clinical and epidemiological analyses 01 pediatric infections caused by Parainfluenza viruses types 1-4 during the period of 2013-2014

Introducción. Las infecciones respiratorias víricas agudas son una entidad que afecta preferentemente a la población infantil. Los virus de la Parainfluenza (VPI) (tipos 1-4) son responsables de un porcentaje variable de estas infecciones. Pacientes y métodos. Se presenta un estudio prospectivo sobre las infecciones respiratorias agudas causadas por los diferentes tipos de los VPI. A los pacientes se les tomó una muestra respiratoria que fue estudiada mediante una RT-PCR múltiple comercial que permite la detección de 16 virus distintos y los cuatro tipos de los VPI. Resultados. En este estudio se han analizado 2.854 muestras, de las cuales 1.412 (49,5%) fueron positivas. Se han detectado 89 casos de infección por los VPI (6,3%). Los VIP correspondían a 34 VPI-1 (38,2%),9 VPI-2 (10,1 %),29 VPI-3 (32,5%) y 17 VPI-4 (19,1%). En el 78,6% de los casos el VPI se detectó solo y en el 21,4% en coinfección. El 68,5% de los casos se detectaron entre los meses de septiembre y octubre. Las edades de los pacientes estaban comprendidas entre los 21 días y 14 años (media 26,2 meses). El ingreso hospitalario ocurrió en 18 casos (20,2 %). Las patologías respiratorias observadas han ido desde el cuadro catarral hasta las bronquiolitis y neumonías. No se han detectado diferencias significativas entre los diferentes tipos vira les. Conclusiones. Las infecciones respiratorias agudas causadas por los VPI representan alrededor del 6% de los casos. La inespecificidad del proceso infeccioso obliga a realizar el estudio etiológico para poder ser atribuidas a un determinado agente viral (AU)

Introduction. The acute viral respiratory infections are an entity that preferentially affect children. Para influenza viruses (PIV) (types 1-4) are responsible for a varying percentage of these infections. Patients and methods. A prospective study of acute respiratory infections caused by different types of PIV is presented. AII patients were taking a respiratory sample that was studied with a commercial multiple RT-PCR which allows the detection of 16 different viruses, including the four types of the PIV. Results. In this study we have analyzed 2,854 samples, of which 1,412 (49.5%) were positive. We detected 89 cases of infection by PIV (6.3%). 34 corresponding to the VIP-1 (38.2%), 9 VPI -2 (10.1%),29 VPI-3 (32.5%) and 17 VPI-4 (19.1 %). In 78.6% of cases was detected only the PIV and 21.4% in coinfection. 68.5% of cases were detected between the months of September and October. The ages of the patients ranged from 21 days to 14 years (mean 26.2 months). Hospital admission occurred in 18 cases (20.2%). Respiratory diseases have been observed from cold symptoms to bronchiolitis and pneumonia. No significant differences were detected between the different viral types. Conclusions. Acute respiratory infections caused by PIV represent about 6% of cases. They affect both sexes equally and present with a variety of respiratory diseases. The specificity of the infectious process requires performing the etiologic study to be attributed to a specific viral agent (AU)