Metapneumovirus Infection In Children Research Articles

Metapneumovirus infection in children in modern conditions: clinical and immunological parallels

Aim. The study of metapneumovirus infection clinical and immunological features in children of different ages. Patients and methods. An analysis of 22 patients with mono-metapneumovirus infection is presented. There were 7 (31.8%) children under the age of 1 year, 8 (36.4%) — 1—3 years old, 7 (31.8%) — 4—7 years old. Diagnosis of metapneumovirus infection was based on clinical data and on PCR analysis of nasopharyngeal mucus. Immunological studies in 10 patients included immunophenotype of patient's blood lymphocytes and analysis of the interferon system. Results. Among children under the age of 1 year 71.4 ± 17.1% were diagnosed with obstructive bronchitis and 28.6 ± 17.1% had pneumonia. In patients aged 1—3 years pneumonia was observed more often (55.6 ± 17.6%), obstructive bronchitis — less often (33.3 ± 16.7%), and in 11.1 ± 11.1% bronchitis occurred without symptoms of bronchial obstruction. In children aged 4—7 years only the upper respiratory tract was affected in 14.3 ± 13.2% of cases, 57.1 ± 18.7% developed bronchitis and 28.6 ± 17.1% — pneumonia. The immune system state was characterized by a low content of T-helpers (CD3 + CD4 + ) and NK-cells (CD3-CD16 + CD56 + ) detected in 7 (70%) and 5 (50%) patients respectively. IFNγ production was reduced in 70% of children and IFNα in 80%. Conclusion. Metapneumovirus infection in children in modern conditions is characterized by the frequent development of inflammatory changes in the bronchopulmonary system in the early stages of the disease. The disease severity was due to both manifestations of respiratory failure and severe symptoms of intoxication. Immunological studies revealed changes in the cellular link and the interferon system in all age groups.

Epidemiology and Clinical Characteristics of Human Metapneumovirus Infections in Hospitalized Children in Two Consecutive Postpandemic Years.

We assessed human metapneumovirus infections in children hospitalized between 2011 and 2023 and compared the strongest pre- and postpandemic seasons. After the COVID-19 pandemic, we observed offseason cases and loss of the alternating pattern of the human metapneumovirus season magnitude. Incidence rate ratio of 0- to 11-month-old versus 12- to 23-month-old children was 2.1 (95% CI: 1.0-4.8) before and 1.3 (95% CI: 0.6-2.9) after the pandemic.

Epidemiology, genetic characteristics, and association with meteorological factors of human metapneumovirus infection in children in southern China: A 10-year retrospective study

ObjectivesThis study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. Methods14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. ResultsHMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. ConclusionHMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence.

Metapneumovirus infection in children

Objective: to study the clinical features of metapneumovirus infection in children of different ages in a hospital.
 Materials and methods. A retrospective analysis of medical records of 142 patients aged 1 month to 14 years inclusive who were hospitalized in the period from January 2012 to April 2019. Metapneumovirus infection was confirmed by hMPV nucleic acid isolation by PCR in nasopharyngeal smears.
 Results. Metapneumovirus infection is detected among hospitalized children with acute respiratory viral infections in 4,4% of cases. In the age structure, 72,2% are children under 4 years old, and the maximum incidence rate is among children aged 3 years of life. The leading clinical symptoms are cough in 93,0% of cases and rhinitis in 96,5% of cases.In 88,2% of children, the disease proceeds with an increase in temperature 38 C, including in 34,6% 39,5 C and above. Symptoms of gastrointestinal dysfunction in the form of vomiting and diarrhea develop in 26,1% and 22,5% of children, respectively. 78,2% of patients requiring hospitalization suffer hMPV infection with damage to the lower respiratory tract, including in the form of bronchitis in 85,6% of cases and pneumonia in 14,4% of cases. The disease is complicated by the development of bronchial obstructive syndrome in 38,7% and acute respiratory failure in 22,3% of cases. ARF and BOS are significantly more likely to develop in children of the first 3 years of life 71,0% versus 29,0% in children of the older age group (p = 0.038) and 69,8% against 30,2% (p = 0.007), respectively. In a clinical blood test for hMPV infection, leukopenia and leukocytosis are detected only in 3,5% and 12,7% of cases, respectively, as well as an increase in ESR in 23,9% of children. The level of CRP in the 93,0% of children was less than 20 mg/l.
 Conclusions. Virological confirmation of metapneumovirus infection in hospitalized children with lower respiratory tract infections contributes to the formation of an adequate therapeutic tactic.

A review on epidemiology and impact of human metapneumovirus infections in children using TIAB search strategy on PubMed and PubMed Central articles.

Acute respiratory tract infections (ARTI) contribute to morbidity and mortality in children globally. Viruses including human metapneumovirus (hMPV) account for most ARTIs. The virus causes upper and lower respiratory tract infections mostly in young children and contributes to hospitalization of individuals with asthma,chronic obstructive pulmonary diseases and cancer. Moreover, hMPV pauses a considerable socio-economic impact creating a substantial disease burden wherever it has been studied, although hMPV testing is relatively new in many countries. We aimed to comprehensively analyze the epidemiological aspects including prevalence, disease burden and seasonality of hMPV infections in children in the world. We acquired published data extracted from PubMed and PubMed Central articles using the title and abstract (TIAB)search strategy for the major key words on hMPV infections from 9/54 African, 11/35 American, 20/50 Asian, 2/14 Australian/Oceanian and 20/51 European countries. According to the findings of this review, the prevalence of hMPV infection ranges from 1.1 to 86% in children of less than 5 years of age globally. Presence of many hMPV genotypes (A1, A2, B1, B2) and sub-genotypes (A2a, A2b, A2c, B2a, B2b) suggests a rapid evolution of the virus with limited influence by time and geography. hMPV infection mostly affects children between 2 to 5 years of age. The virus is active throughout the year in the tropics and epidemics occur during the winter and spring in temperate climates, contributing to a substantial disease burden globally.

Clinical-epidemiological peculiarities of acute respiratory infections in children from 3 to 12 years and evaluation of effectiveness of antivirus therapy

The aim: to study the etiological structure of acute respiratory infections in children aged 3 to 12 hospitalized in the early stages of the disease in the department of respiratory infections of the children’s hospital, and to reveal the features of their clinical course and the timing of DNA / RNA elimination of respiratory viruses from nasal secretions, depending on the method of therapy. Materials and methods: 100 children with acute respiratory infections aged 3 to 12 years were monitored. The nasal secrets on the DNA / RNA of respiratory viruses were studied by PCR. Depending on the method of therapy, patients were divided into 2 groups: patients of group 1 (comparison) received basic treatment (without the use of antiviral drugs), in patients of the 2nd group (main), along with basal therapy, the drug was used umifenovir in a 5-day course at the ageappropriate dosage. Results: In the etiologic structure of ARVI in children from 3 to 12 years, the leading place was taken by rhinovirus, influenza and metapneumovirus infections (isolated – 18%, 19% and 20% respectively, in the form of a mixed infection – 11%). The main syndromic diagnosis at the height of the disease was rhinopharyngitis. Complications were observed in 42% of cases, as often as possible with flu – 53% of cases. Features of metapneumovirus infection in children of this age group were: predominance of non-severe forms of the disease in the form of acute fever with symptoms of rhinopharyngitis, as well as a small incidence of lower respiratory tract infections. The use of the drug umiphenovir in children with acute respiratory viral infections of various etiologies contributed to significantly faster elimination of viral DNA / RNA from the nasal secretion, which was accompanied by a ecrease in the duration of the main clinical and hematological symptoms of the disease, a decrease in the incidence of complications, and reduced the duration of stay in hospital. Conclusion: application of modern molecular genetic methods of diagnostics made it possible to identify the leading role of influenza, metapneumovirus and rhinovirus infections in the etiology of acute respiratory viral infection in patients aged 3 to 12 years, and to determine a number of clinical features characteristic of this age group. The results of the study testify to the effectiveness of umiphenovir in the treatment of children with acute respiratory viral infections of various etiologies and allow us to recommend this drug as an effective and safe etiotropic agent.

Detection of human Metapneumovirus infection in children under 18 years old hospitalized in Lima-Peru.

BackgroundHuman Metapneumovirus (hMPV) is a negative single-stranded RNA virus. Infection by hMPV mainly affects the pediatric population and can cause upper or lower respiratory tract pathologies which can develop life threating complications. This study was carried out between 2009 and 2010 in a high complexity national hospital in Lima, Peru. The time frame corresponds to the pandemic of influenza A H1N1.MethodsA prospective study was performed between September 2009 and September 2010. Patients with a clinical diagnosis suggestive of an acute respiratory infection were included. RT-PCR was utilized to attain the amplification and identification of the hMPV.ResultsA total of 539 samples were analyzed from patients with a clinical context suggestive of an acute respiratory tract infection. Of these samples 73, (13.54%) were positive for hMPV. Out of the positive cases, 63% were under one year old, and increased to nearly 80% when considering children younger than two years old. Cough was the most frequent symptom presented by our population with a number of 62 cases (84.93%). Viral seasonality was also established, noting its predominance during the months of summer in the southern hemisphere. The infection by hMPV has an important prevalence in Peru. It mainly affects children under one year old and should be considered an important differential diagnosis in a patient with an acute respiratory infection.

The epidemiology and clinical manifestation of human metapneumovirus infection in children during 2011–2014

Purpose: This study was performed to investigate the epidemiologic and clinical features of human metapneumovirus (hMPV). Methods: We performed real-time reverse transcription polymerase chain reaction with nasopharyngeal samples from 2,403 chil-dren who were hospitalized with acute respiratory infection. Then medical records of 120 children, who were diagnosed with hMPV respiratory infection between 2011 and 2014, were retrospectively analyzed retrospectively and compared to epidemiologic data on respiratory virus infection reported by Korea Centers for Disease Control and Prevention. Results: We detected 120 hMPV-positive cases out of 1,723 virus-positive specimens (7.0%), which prevailed mostly in spring be-tween March and May. Respiratory infection with hMPV was more common in female patients (55.0%) and hPMV infection was prevalent among children aged <5 years (80.8%). Coinfections with other respiratory viruses were observed in 34 patients of 120 hMPV-positive cases (28.3%), mostly with rhinovirus (52.9%). In addition, hPMV infection mostly presented with pneumonia (71.7%). Among 120 hMPV-positive patients during the recent 4 years, most (68.3%) were diagnosed in 2014. During 2011-2014, influenza virus infection was prevalent mainly from January to March, and hMPV infection started to appear just after the end of influenza vi-rus outbreak. Conclusion: In Korean children, hMPV was a common causative organism of viral pneumonia during the spring season. The hMPV infection pandemic was observed in 2014 and the clinical importance of hMPV has recently been increasing. Therefore, additional studies are required to define the epidemiology, disease characteristics caused by hMPV, and the cause of recent outbreak. (Allergy Asthma Respir Dis 2017;5:269-273)

Clinical and genetic features of human metapneumovirus infection in children.

Human metapneumovirus (hMPV) is one of the main pathogens responsible for respiratory tract infection in children. From 2011 to 2013, nasopharyngeal aspirates were obtained from Korean children and tested for hMPV on reverse transcription-polymerase chain reaction (RT-PCR). The genotype of hMPV in each sample was identified on PCR-restriction length polymorphism analysis of the fusion gene. We divided patients into three groups according to degree of fever. Patients with fever peaking at >39.5°C or lasting >7 days were classified as the high fever (HF) group; those with fevers peaking at <38.5°C and lasting <72 h were classified as the low fever (LF) group; and the other subjects were classified as the moderate fever group. Among 457 samples positive for hMPV, hMPV genotype was able to be identified in 399 (87.3%); of these, A2a was found in 97 (24.3%), B1 in 186 (46.6%), and B2 in 116 (29.1%). Clinical features of hMPV infection were compared between the HF and LF groups. We classified 80 subjects into the HF group and 84 subjects into the LF group. Mean absolute neutrophil count (5625 ± 4418 vs 4072 ± 3076/μL, P = 0.010) and C-reactive protein (2.39 ± 3.39 vs 0.96 ± 1.77 mg/dL, P = 0.001) were higher in the HF group. Wheezing (5.0% vs 32.1%, P < 0.001) and dyspnea (2.5% vs 15.5%, P = 0.010) were more frequently seen in the LF group. Genotype distribution was similar in the two groups. Two distinct clinical presentations of hMPV infection were identified in this study.

Human metapneumovirus infection among outpatient children in Dibrugarh.

We describe the prevalence of human metapneumovirus infection in children visiting outpatient department with symptoms of respiratory illness in rural areas of Dibrugarh District of Assam. Human metapneumovirus was observed in 7.2% (20/276) of children aged =5 years with detection of genotypes A2b and B2.

Clinical analysis on human metapneumovirus infection in children with respiratory

Objective To analyze clinical features of human metapneumovirus (hMPV) in children with respiratory tract infection,providing reference for better observation and treatment for children with respiratory tract metapneumovirus infections.Methods 1798 cases of acute respiratory infections from June 2008 to June 2010 were selected,and their fresh sputum were taken as respiratory specimens tested by the presence of hMPV with reverse-transcription polymerase Chain reaction(RT-PCR).PCR products of hMPV N gene from some patients were randomly selected for sequencing analysis,and the sequences of the nucleotides and amino acids were compared with those in the GennBank.The hMPV infection detection was made,peripheral blood routine check,chest X-ray,C-reactive protein,and clinical data were all recorded.Results 43 cases of hMPV were found (positive rate of 46.7％) in cases aged less than 6months,9 patients (9.8％) in 6 months to 1-year-old group,27 patients (29.3％) in 1 to 3-year-old group,10 cases (10.9％) in 3 to 7-year-old group,3 cases (3.3％) in 7 to 14-year-old group.The clinical manifestations of hMPV infection were as follows:cough (89.1％),fever (73.9％),pulmonary rales (51.1％),wheezing (33.7％),dyspnea (8％).Conclusion It shows that hMPV is associated with children suffering respiratory tract infections in some area in Guangzhou and it exits for the full year with infection peak of the epidemic from March to April in a year.The infection rate is higher in children aged less than 6months,there isn no specific clinical features in hMPV infection,with only fever,cough,or wheezing. Key words: Respiratory tract infections; Human metapneumovirus; Clinical manifestations

Molecular epideiological and clinical feature of human metapneumovirus in children with acute respiratory tract infection in Nanjing City

To investigate the molecular epideiological and clinical feature of human metapneumovirus in children with acute respiratory tract infection in Nanjing city, China. Nasopharyngeal aspirates and nasopharyngeal swab were taken from 642 outpatients or hospitalized pediatric patients with acute at the Children Hospital of Nanjing, Jiangsu Province, China, between August 2009 and July 2010. Respiratory speciments were tested for the M gene of hMPV by reverse-transcription polymerase chain reaction (RT-PCR). All RT-PCR positive products were sequenced and phlogenetic analysis was conducted. hMPV was detected in 35 (5.5%) of the 642 children. Phylogenetic analysis revealed that 51.4% of the hMPV were B1, 31.4% were A2b. The peak of the positive rate was in April. The majority of the hMPV-positive patients(71.4%) were 0-1 years old. Of the 35 hMPV-positive patients, 15 (42.8%) were co-infected with other respiratory viruses, and human rhinovirus (HRV) were the most common additional respiratory virus. The most common clinical diagnosis was pneumonia (48.6%). Human metapneumovirus is an important pathogen of acute respiratory tract infection in children in Nanjing city. The subtype B1 was the predominating lineage in 2009-2010 in Nanjing city. No significant differences were found for clinical characteristics between genotype A and genotype B human metapneumovirus infection in children in Nanjing.

Human Metapneumovirus Infection In Children with Cancer

AbstractAbstract 3910The human metapneumovirus (HMPV) is a paramyxovirus that has been recently associated with respiratory tract infections in children. HMPV was first described in 2001 by researchers in the Netherlands. Since this initial report, HMPV has been reported from many other countries across the world. HMPV was found to be the second most frequent cause, after RSV, of viral respiratory infections in children less than 1 year of age. In hospitalized children, the most frequent clinical manifestations associated with HMPV are pneumonitis, bronchiolitis and asthma. Severe HMPV infection can also occur in the elderly and in immunocompromised patients. We carried out a retrospective study to describe the clinical features and severity of HMPV in pediatric oncology patients at The Hospital for Sick Children.Thirty one children with cancer found to have HMPV infection during the study period from January 2005 till December 2010. HMPV was isolated by nasopharyngeal (NP) swab in 30/31 patients while one patient had bronchalveolar lavage (BAL). Direct fluorescent-antibody (DFA) was positive in all 31 patients while 13 patients also had viral culture positive. Eight patients had culture negative while this test was not done in 10 patients (after December 2008). The majority of HMPV infection was diagnosed in the winter months from November to March and also in the spring till May. Of 31 patients, 13 were male and 18 were female. The most common underlying diagnosis was leukemia 14/31 (45.1%). Nine patients had different types of solid tumours including 3 with neuroblastoma, 2 with rhabdomyosarcoma, 1 with hepatoblastoma, 1 with nasopharyngeal sarcoma, and 1 with undifferentiated sarcoma. Twenty-nine of thirty-one (93.5%) of the patients presented with cough, 24/31 (77.4%) with fever, 16/31 (51.6%) with rhinorrhea. Vomiting was noticed in 25.8% of the patients and diarrhea in 32.2%. Sixteen of thirty-one (51.6%) patients were diagnosed with upper respiratory tract infection (URTI), 7/31 (22.5%) patients were diagnosed as bronchiolitis and 8/31 (25.8%) diagnosed to have pneumonia. 19.3% (6/31) patients had co-infection with different organisms including coagulase negative Staphylococcus and Streptococcus pneumoniae requiring antibiotic treatment. The average duration of symptoms on presentation was 7 days (1-90 days). One patient with average risk acute lymphoblastic leukemia on maintenance treatment presented with 3 months history of cough and subsequently NP swab and BAL were positive for HMPV. He required prolonged therapy with inhaled bronchodilator and steroid. Twenty of thirty-one (64.5%) patients were admitted. The average duration of admission was 18.3 days and average duration of respiratory illness was 13.5 days. None of the patient required mechanical ventilation because of HMPV infection. Twenty-one of thirty-one patients were treated with antibiotics for duration of 3 to 14 days. One patient was empirically treated with oseltamivir (Tamiflu). All of the patients recovered from their viral illness completely, only one patient had prolonged respiratory symptoms for six months. Conclusion:Our study showed HMPV is an important respiratory virus causing both upper respiratory tract illness (URTI) and lower respiratory tract illness (LRTI) in children with cancer. Although the majority of the children recovered from HMPV infection without clinically significant illness, a minority had prolonged respiratory illness requiring supportive treatment. Disclosures:No relevant conflicts of interest to declare.

Usefulness of two new methods for diagnosing metapneumovirus infections in children

Human metapneumovirus (hMPV) is associated with acute respiratory tract infections, mainly in paediatric patients. The aim of this study was to evaluate the usefulness of two new commercial techniques available for the detection of hMPV in clinical samples from children: an enzyme immunoassay, hMPV EIA (Biotrin International Ltd), and a molecular assay, real-time RT-PCR (Pro hMPV Real Time Assay Kit; Prodesse). A total of 184 nasopharyngeal aspirate specimens from 173 children aged less than 5 years who were hospitalized with acute wheezing were analysed. Respiratory syncytial virus was detected in 27% of the samples, followed by influenza A virus (6%), parainfluenza virus (PIV)3 (2.2%), adenovirus (2%), PIV1 (1.1%), PIV2 (1.1%), and influenza B virus (0.5%). The presence of hMPV was tested in all samples, using the real-time RT-PCR and EIA. Real-time RT-PCR detected 13 hMPV-positive samples (8%), and EIA detected 17 (9.3%). When the EIA results were compared with those of real-time RT-PCR for the detection of hMPV, a good correlation was found (94%). A relatively low co-infection rate (15%) was observed in our patients. RT-PCR and EIA provide robust methods for the diagnosis of hMPV infection in children.

High seroprevalence of human metapneumovirus infection in children in Chongqing, China

The human metapneumovirus (hMPV) is a newly discovered respiratory viral pathogen that was first isolated in 2001 in the Netherlands. Its global distribution and long history of infection in humans have been well documented. In this study, we assessed the seropositivity of hMPV IgG antibodies in children in Chongqing, China. The specificity of the enzyme linked immunosorbent assay (ELISA) was first validated by using respiratory syncytial virus (RSV) infected, antigen subtracted reference serum and by performing western blotting using anti-hMPV animal serum. This assay was used to determine the presence of the IgG antibody against hMPV and RSV in 325 serum samples obtained from children aged 0 - 6 years. No crossreaction was detected by ELISA between the antibodies to hMPV and RSV. The seropositivity of the anti-hMPV IgG antibody was 74.5% in children aged 0 to 5 months, 64.0% in 6 to 11 months, 72.7% in 12 to 23 months, 87.1% in 24 to 35 months and 90.3% in 3 to 6 years. hMPV is a common and significant respiratory pathogen in Chinese children. Almost all individuals are exposed to hMPV by age 6 years.

Seasonal Invasive Pneumococcal Disease in Children: Role of Preceding Respiratory Viral Infection

Our objective was to demonstrate correlations between invasive pneumococcal disease in children and circulating respiratory viruses. This retrospective study included 6 winter respiratory viral seasons (2001-2007) in Intermountain Healthcare, an integrated health system in the Intermountain West, including Primary Children's Medical Center in Salt Lake City, Utah. Children <18 years of age who were hospitalized with either invasive pneumococcal disease in any Intermountain Healthcare facility or culture-confirmed invasive pneumococcal disease at Primary Children's Medical Center were included. We analyzed the correlation between invasive pneumococcal disease and circulating respiratory viruses. A total of 435 children with invasive pneumococcal disease and 203 with culture-confirmed invasive pneumococcal disease were hospitalized in an Intermountain Healthcare facility or Primary Children's Medical Center during the study period. During the same period, 6963 children with respiratory syncytial virus, 1860 with influenza virus, 1459 with parainfluenza virus, and 818 with adenoviruses were evaluated at Primary Children's Medical Center. A total of 253 children with human metapneumovirus were identified during the last 5 months of the study. There were correlations between invasive pneumococcal disease and seasonal respiratory syncytial virus, influenza virus, and human metapneumovirus activity. The correlation with invasive pneumococcal disease was strong up to 4 weeks after respiratory syncytial virus activity. For influenza virus and human metapneumovirus, the correlations were strong at 2 weeks after activity of these viruses. Pneumonia was the most common clinical disease associated with culture-confirmed invasive pneumococcal disease, mostly attributable to serotypes 1, 19A, 3, and 7F. In the post-pneumococcal conjugate vaccine era, seasonal increases in respiratory syncytial virus, influenza virus, and human metapneumovirus infections in children were associated with increased pediatric admissions with invasive pneumococcal disease, especially pneumonia caused by nonvaccine serotypes.

Clinical findings and unusual epidemiologic characteristics of human metapneumovirus infections in children in the region of Basel, Switzerland

Human metapneumovirus (hMPV) worldwide causes respiratory tract infections with features similar to those of RSV infection. We describe features of hMPV infections in children and compare some of the characteristics with those of RSV infections. From October 2004 to February 2006, 75 patients, 34 hospitalized and 41 outpatients, were diagnosed with hMPV infections by multiplex PCR applied to nasopharyngeal specimens. While hMPV was found rarely in the early phase of the study, a significant increase occurred in the second winter of the study period. Patients with hMPV infections were older than those with RSV infection; clinical characteristics were similar as was the rate of serious disease among hospitalized patients (intensive care treatment: 18% versus 8%). In conclusion, hMPV leads to endemic and epidemic respiratory disease with features similar to those of RSV and should be considered in the differential diagnosis of upper and lower respiratory tract disease.

Clinical features of human metapneumovirus infection in children with acute respiratory tract infections

Clinical features of human metapneumovirus infection in children with acute respiratory tract infections

Differences in Clinical Severity between Genotype A and Genotype B Human Metapneumovirus Infection in Children

The clinical spectrum of 69 episodes of metapneumovirus pediatric infection (55 episodes caused by genotype A and 14 episodes caused by genotype B) was analyzed. Diagnosis of pneumonia was more common and the illness severity index (determined on the basis of need for hospitalization, oxygen saturation <90%, and intensive care unit stay) was higher for patients with metapneumovirus genotype A infection.

Seasonality and clinical features of human metapneumovirus infection in children in Northern Alberta

Human metapneumovirus (hMPV) causes respiratory tract infections in all age groups. The characteristics of pediatric hMPV infection in Northern Alberta have not been studied. The objectives of this study were to determine the seasonality of pediatric hMPV infections over a 13-month period, the genetic relationship of hMPV isolates to hMPV detected in other parts of Canada, and the burden of illness and possible risk factors for pediatric hMPV hospitalization. Detection of hMPV by polymerase chain reaction was performed on nasopharyngeal specimens collected from outpatients and inpatients at the Stollery Children's Hospital in Edmonton, Alberta, November 12, 2002-December 31, 2003. Forty-two of 1,079 specimens were positive for hMPV (3.9%) from 41 patients (14 outpatients and 27 inpatients), with a peak incidence during January-April, but isolates were detected 10 months of the year. Co-infection was not detected in 39 specimens from which RSV had been detected. Two hMPV genetic clusters were detected, and the isolates were homologous to those of previous Canadian isolates. Four of the 14 outpatients had reactive airways disease. Possible risk factors in the 27 inpatients included prematurity (n = 8), congenital heart disease (n = 6), gastroesophageal reflux disease or aspiration (n = 6), global developmental delay (n = 5), and multiple congenital anomalies (n = 4). Risk factors for hospitalization appear to be similar to risk factors for respiratory syncytial virus hospitalization.