Parylene Double-Layer Coated Screen-Printed Carbon Electrode for Label-Free and Reagentless Capacitive Aptasensing of Gliadin.

Celiac patients are required to strictly adhere to a gluten-free diet because even trace amounts of gluten can damage their small intestine and leading to serious complications. Despite increased awareness, gluten can still be present in products due to cross-contamination or hidden ingredients, making regular monitoring essential. With the goal of guaranteeing food safety for consuming labeled gluten-free products, a capacitive aptasensor was constructed to target gliadin, the main allergic gluten protein for celiac disease. The success of capacitive aptasensing was primarily realized by coating a Parylene double-layer (1000 nm Parylene C at the bottom with 400 nm Parylene AM on top) on the electrode surface to ensure both high insulation quality and abundant reactive amino functionalities. Under the optimal concentration of aptamer (5 µM) used for immobilization, a strong linear relationship exists between the amount of gliadin (0.01-1.0 mg/mL) and the corresponding ΔC response (total capacitance decrease during a 20 min monitoring period after sample introduction), with an R2 of 0.9843. The detection limit is 0.007 mg/mL (S/N > 5), equivalent to 0.014 mg/mL (14 ppm) of gluten content. Spike recovery tests identified this system is free from interferences in corn and cassava flour matrices. The analytical results of 24 commercial wheat flour samples correlated well with a gliadin ELISA assay (R2 = 0.9754). The proposed label-free and reagentless capacitive aptasensor offers advantages of simplicity, cost-effectiveness, ease of production, and speediness, making it a promising tool for verifying products labeled as gluten-free (gluten content <20 ppm).

Viral load and clinical features in children infected with seasonal influenza B in 2006/2007.

BACKGROUND/PURPOSE: In influenza B infection, viral load is believed to be related to the severity of clinical illness. The correlation between viral load and symptoms is not known. We conducted a study to assess the relationship between virus load and clinical features in children infected with influenza B, in the hope that clinical features could be used as surrogate markers of viral load to guide treatment. METHODS: Between December 2006 and February 2007, 228 patients with fever and respiratory symptoms were prospectively enrolled in our tertiary hospital-based study. Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to determine viral load. RESULTS: Real-time RT-PCR was positive for influenza B in 76 patients. Using virus culture as the gold standard, the sensitivity and specificity were 95% and 87%, respectively. Influenza culture positive rate significantly correlated with viral load (p = 0.03). The median copy number of influenza B virus in the 76 RT-PCR positive patients was 9735 copies/ml (range 4.8×10¹-2.0×106 copies/ml). Samples obtained later in the clinical course tended to have lower viral load (p = 0.7), while patient age (p = 0.72) and fever duration (p = 0.96) positively related to viral load. In patients >3 years of age, myalgia was related to statistically lower viral loads (14300 vs. 1180; p = 0.025). Patients with chills tended to have higher viral loads (72450 vs. 7640; p = 0.1). Patients with abdominal pain tended to have lower viral loads (1998 vs. 12550; p = 0.06). CONCLUSION: Culture rate positively correlated with viral load. Patients with myalgia had a lower viral load.

Serologic status for pandemic (H1N1) 2009 virus, Taiwan.

We studied preexisting immunity to pandemic (H1N1) 2009 virus in persons in Taiwan. A total of 18 (36%) of 50 elderly adults in Taiwan born before 1935 had protective antibodies against currently circulating pandemic (H1N1) 2009 virus. Seasonal influenza vaccines induced antibodies that did not protect against pandemic (H1N1) 2009 virus.

Vapor Sublimation and Deposition to Fabricate a Porous Methyl Propiolate-Functionalized Poly-p-xylylene Material for Copper-Free Click Chemistry.

Conventional porous materials are mostly synthesized in solution-based methods involving solvents and initiators, and the functionalization of these porous materials usually requires additional and complex steps. In the current study, a methyl propiolate-functionalized porous poly-p-xylylene material was fabricated based on a unique vapor sublimation and deposition process. The process used a water solution and ice as the template with a customizable shape and dimensions, and the conventional chemical vapor deposition (CVD) polymerization of poly-p-xylylene on such an ice template formed a three-dimensional, porous poly-p-xylylene material with interconnected porous structures. More importantly, the functionality of methyl propiolate was well preserved by using methyl propiolate-substituted [2,2]-paracyclophane during the vapor deposition polymerization process and was installed in one step on the final porous poly-p-xylylene products. This functionality exhibited an intact structure and reactivity during the proposed vapor sublimation and deposition process and was proven to have no decomposition or side products after further characterization and conjugation experiments. The electron-withdrawing methyl propiolate group readily provided efficient alkynes as click azide-terminated molecules under copper-free and mild conditions at room temperature and in environmentally friendly solvents, such as water. The resulting methyl propiolate-functionalized porous poly-p-xylylene exhibited interface properties with clickable specific covalent attachment toward azide-terminated target molecules, which are widely available for drugs and biomolecules. The fabricated functional porous materials represent an advanced material featuring porous structures, a straightforward synthetic approach, and precise and controlled interface click chemistry, rendering long-term stability and efficacy to conjugate target functionalities that are expected to attract a variety of new applications.

Safety and immunogenicity of a tetravalent polysaccharide vaccine against meningococcal disease.

BACKGROUND/PURPOSE: Meningococcal disease, including meningitis and sepsis, usually follows an invasive infection by Neisseria meningitidis, and is a major cause of death and morbidity worldwide. Currently available meningococcal vaccines that consist of pure capsular polysaccharides (serogroups A, C, W-135 and Y) are generally safe and efficacious in adults and children aged > 2 years. The purpose of this study was to evaluate the immunogenicity, safety and reactogenicity of a single dose of GlaxoSmithKline Biologicals' Mencevax ACWY vaccine in healthy Taiwanese subjects aged 2-30 years. METHODS: This open, single center, Phase III study was conducted in Taiwan. A single dose of the Mencevax ACWY vaccine was administered to subjects aged 2-30 years. Immunogenicity and safety of the vaccine were evaluated after vaccination. RESULTS: The immunogenicity results obtained 1 month after vaccination with Mencevax ACWY vaccine indicated that the vaccine elicited a good immune response in vaccinees aged 2-30 years. This was both in terms of functional activity directed against meningococcal polysaccharide (A, C, W-135 and Y) as measured by serum bactericidal assay (> 93% activity against all serogroups), and specific IgG concentrations measured by ELISA (> 96% seropositivity to all serogroups). CONCLUSION: The tetravalent polysaccharide Mencevax ACWY meningococcal vaccine was well tolerated and immunogenic in subjects aged 2-30 years in Taiwan.

Establishment of a young mouse model and identification of an allelic variation of zmpB in complicated pneumonia caused by Streptococcus pneumoniae.

OBJECTIVE: Complicated pneumonia, including necrotizing pneumonia, lung abscess, and empyema, caused by Streptococcus pneumoniae in children has been increasing. We thus determined to investigate its virulence in an animal model and to identify virulence factors of S. pneumoniae. DESIGN: Prospective, randomized, controlled animal study. SETTING: University medical laboratory. SUBJECTS: Male Balb/c-strain mice, 3 wks old. INTERVENTIONS: We used a young mouse model to monitor bacterial virulence and a microarray to compare gene expression between S. pneumoniae from children with complicated and noncomplicated pneumonia. Deletion and complementation of a candidate gene were performed to study its role on the virulence of S. pneumoniae. MEASUREMENTS AND MAIN RESULTS: A model of complicated pneumonia in young mice infected with strains of S. pneumoniae from children with complicated pneumonia was established. Using a microarray analysis, differences in zinc metalloprotease B (zmpB) RNA hybridization between two strains from children with complicated pneumonia (NTUH-p28 and NTUH-p15) and a strain (NTUH-p3) from a child with pneumococcal lobar pneumonia were found. Confirmatory assays revealed the signal differences were due to sequence variation in the zmpB gene. Infection with the zmpB deletion mutant of NTUH-p15 showed a significant decrease in the severity of pneumonia and no destructive lung injury. The zmpB complementation strain of NTUH-p15 significantly restored the level of inflammation and caused lung necrosis. For studying the effect of allelic variation of zmpB on the virulence of S. pneumoniae, we added zmpB of NTUH-p15 in the zmpB deletion mutant of NTUH-p3, which resulted in a higher bacterial burden than that in wild-type NTUH-p3. CONCLUSIONS: A young mouse model is established for complicated pneumococcal pneumonia. This model proved that allelic variation of zmpB affects the virulence of S. pneumoniae.

An open, randomized, comparative study of clarithromycin and erythromycin in the treatment of children with community-acquired pneumonia.

BACKGROUND AND PURPOSE: This study aimed to evaluate the efficacy and safety of clarithromycin and erythromycin in the treatment of community-acquired pneumonia in children. METHODS: Children with community-acquired pneumonia were randomly assigned to receive 10-day regimens of either clarithromycin 15 mg/kg/day, twice a day, or erythromycin 30-50 mg/kg/day, four times daily. RESULTS: A total of 97 children entered this study, including 26 with Mycoplasma pneumoniae infection, 15 with Chlamydia pneumoniae infection, and 6 with mixed mycoplasma and chlamydia infections. Fifty and 47 children received clarithromycin and erythromycin treatment, respectively. Three children withdrew from the study because the identified pathogens were resistant to the study drugs. All 47 children with mycoplasma or chlamydia infection were cured clinically. Delayed defervescence, defined as a fever lasting for more than 72 h after treatment, was observed in 4 of 22 clarithromycin-treated children (18%) and in 3 of 15 erythromycin-treated children (20%) [p>0.05]. Gastrointestinal side effects, including vomiting, abdominal pain and diarrhea, were observed in 3 of 50 children (6%) receiving clarithromycin and in 11 of 49 children (22%) receiving erythromycin (p=0.039). Excluding children with abnormal pretreatment liver function, abnormal liver function after treatment was observed in only one child, treated with erythromycin. Post-treatment eosinophil and platelet counts were significantly elevated after treatment in both groups. CONCLUSIONS: Clarithromycin showed efficacy equivalent to erythromycin for the treatment of mycoplasma or chlamydia pneumonia in children. However, the tolerability of clarithromycin was superior to that of erythromycin.

Clinical manifestations of human coronavirus NL63 infection in children in Taiwan.

Human coronavirus NL63 (HCoV-NL63) is a global respiratory tract pathogen; however, the epidemiology of this virus in subtropical area is not well known. To evaluate the epidemics and disease spectrum of HCoV-NL63 infection in children in Taiwan, we prospectively screened children admitted to the hospital with respiratory tract infection from May 2004 to April 2005. Every enrolled child had a nasopharyngeal aspirate (NPA) sample taken. Quantitative RT-PCR was used to detect 1b gene of HCoV-NL63. A total of 539 NPAs were collected. Seven (1.3%) were positive for HCoV-NL63. All cases were boys younger than 3 years of age and most cases occurred in autumn. Co-infection with other pathogens was observed in three cases. The most common symptoms/signs of HCoV-NL63 infection were cough, fever, and inspiratory stridor. HCoV-NL63 was the most common pathogen (14.7%) in children with croup and was the cause of three cases of croup in October. The odds ratio of croup in children infected with HCoV-NL63 was 43.4 (95% CI 8.1 approximately 233.1). In conclusion, HCoV-NL63 is an important respiratory tract pathogen as the main cause in children admitted to the hospital in Taiwan.

Astrovirus gastroenteritis in children in Taipei.

BACKGROUND/PURPOSE: A prospective study was initiated to study astroviral infections in Taiwan. METHODS: A total of 415 stool samples were collected and assayed for astrovirus antigen using an enzyme immunoassay. RESULTS: Twelve (2.9%) stool samples from 12 patients were positive for astrovirus antigen. Most patients (8/12) had watery diarrhea which lasted for 2-6 days. The majority of patients recovered without specific treatment, except for two patients who were treated with antibiotics for possible bacterial infections. One patient developed chronic diarrhea and two episodes were nosocomially acquired. A clustering in the autumn and winter, with a peak in December (5/12), was noted. Growth on Caco-2 cells was performed for four specimens with positive astroviral RT-PCR results, and a characteristic cytopathic effect was observed after 4 days. Astroviral RNA was detected in six stool samples using RT-PCR. Five of six strains were serotype 1 and one strain was serotype 3. Sequence homology among the six strains was between 80.5% and 100%. A higher degree of homology (89.9-100%) was noted in the five strains of serotype 1. A phylogenetic study demonstrated two clusters in our strains and Oxford reference strain types 1 and 2. CONCLUSION: Our study results provide further information about the prevalence and span of clinical spectra associated with astroviral infections in Taiwan. The current study showed that infection with astroviruses may be an important cause of gastroenteritis, as well as respiratory symptoms, in infants and children in Taipei.

Clinical characteristics of nosocomial rotavirus infection in children in Taiwan.

BACKGROUND/PURPOSE: The aim of this study was to determine the incidence and clinical characteristics of nosocomial rotavirus infection (NRI) among hospitalized children. METHODS: We collected data of children in the Department of Pediatrics with positive stool rotavirus antigen tests. Cases of an admission diagnosis of acute gastroenteritis or a positive stool rotavirus antigen test within 3 days of admission, representing community-acquired infections, were excluded. Both VP4 and VP7 genotyping of the rotaviruses was done. RESULTS: There were 98 patients who met the inclusion criteria during the 3-year period. The incidence density was 0.58 per 1000 patient-days in our series. Among these patients, 59 (60%) had underlying diseases. The intermediate intensive care unit had the highest incidence density (2.8 per 1000 patient-days). Overcrowding of the care unit, inappropriate hand hygiene, and inadequate isolation and cohorting predisposed to the high rate. Genotypes among 79 (80%) rotaviruses tested showed that 42% belonged to the novel genotype, G9P[8]. CONCLUSION: NRI may cause significant morbidity in hospitalized children, especially young infants and those with underlying diseases. Infection control with hospital surveillance, strict isolation and cohort care should be adopted to prevent the spread of rotavirus among special care units.

Control of an outbreak of pandrug-resistant Acinetobacter baumannii colonization and infection in a neonatal intensive care unit.

OBJECTIVE: To investigate the potential reservoir and mode of transmission of pandrug-resistant (PDR) Acinetobacter baumannii in a 7-day-old neonate who developed PDR A. baumannii bacteremia that was presumed to be the iceberg of a potential outbreak. DESIGN: Outbreak investigation based on a program of prospective hospital-wide surveillance for nosocomial infection. SETTING: A 24-bed neonatal intensive care unit in a 2,200-bed major teaching hospital in Taiwan that provides care for critically ill neonates born in this hospital and those transferred from other hospitals. INTERVENTIONS: Samples from 33 healthcare workers' hands and 40 samples from the environment were cultured. Surveillance cultures of anal swab specimens and sputum samples were performed for neonates on admission to the neonatal intensive care unit and every 2 weeks until discharge. The PDR A. baumannii isolates, defined as isolates resistant to all currently available systemic antimicrobials except polymyxin B, were analyzed by pulsed-field gel electrophoresis. Control measures consisted of implementing contact isolation, reinforcing hand hygiene adherence, cohorting of nurses, and environmental cleaning. RESULTS: One culture of an environmental sample and no cultures of samples from healthcare workers' hands grew PDR A. baumannii. The positive culture result involved a sample obtained from a ventilation tube used by the index patient. During the following 2 months, active surveillance identified PDR A. baumannii in 8 additional neonates, and isolates from 7 had the same electrokaryotype. Of the 9 neonates colonized or infected with PDR A. baumannii, 1 died from an unrelated condition. Reinforcement of infection control measures resulted in 100% adherence to proper hand hygiene protocol. The outbreak was stopped without compromising patient care. CONCLUSIONS: In the absence of environmental contamination, transient hand carriage by personnel who cared for neonates colonized or infected with PDR A. baumannii was suspected to be the mode of transmission. Vigilance, prompt intervention and strict adherence to hand hygiene protocol were the key factors that led to the successful control of this outbreak. Active surveillance appears to be an effective measure to identify potential transmitters and reservoirs of PDR A. baumannii.

Clinical manifestations and quantitative analysis of virus load in Taiwanese children with Epstein-Barr virus-associated infectious mononucleosis.

BACKGROUND AND PURPOSE: To delineate the clinical manifestations in different age groups and to define the viral load in patients with Epstein-Barr virus-associated infectious mononucleosis (EBV-associated IM). METHODS: We reviewed data on 69 children with EBV-associated IM from November 2001 to October 2005. Clinical features were evaluated among four age groups: <3 years, 3 to 5 years, 6 to 9 years and 10 to 18 years. EBV viral load was measured by quantitative real-time polymerase chain reaction (PCR) in 13 patients with 15 specimens. RESULTS: Majority of the children were younger than 7 years of age (76.8%) and the male-to-female ratio was 1.6:1. The symptoms and signs included fever (91.3%), tonsillopharyngitis (88.4%), lymphadenopathy (78.3%) and hepatitis (75.4%). The younger age group had higher monocyte count, lower occurrence of hepatitis, and lower glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) levels than the older age group. The median (range) EBV viral load of peripheral blood mononuclear cells (PBMCs) and plasma in IM patients was 738 (0-7455) copies/mug DNA and 51 (0-957) copies/mL plasma, respectively. The PBMC detection rate was high in the early (within 10 days after onset) and late phase (>10 days after onset) [90-100%]. The plasma detection rate in the early phase (66.7%) was higher than that in the late phase (40%). CONCLUSIONS: The younger age group of EBV-associated IM patients had higher monocyte count, lower occurrence of hepatitis, and lower GOT and GPT levels than the older age group. The PBMC detection rate was almost equally high in both the early and late phases, while the plasma detection rate was higher in the early phase. Quantitative real-time PCR of EBV DNA is useful for diagnosing and monitoring EBV-associated IM, especially in younger children.

Multidrug-resistant Acinetobacter baumannii isolates in pediatric patients of a university hospital in Taiwan.

BACKGROUND AND PURPOSE: Acinetobacter baumannii is one of the common nosocomial pathogens, and the emergence of multidrug-resistant A. baumannii (MDRAB) is a therapeutic problem. We describe the clinical characteristics and outcomes of MDRAB colonization/infection in pediatric patients at the National Taiwan University Hospital. METHODS: Fifty two pediatric patients with 205 MDRAB isolates collected between April 2000 and December 2005 were included for investigation of their clinical characters, presentations, and outcome. RESULTS: Among these 205 isolates, 20 (9.8%) were from sterile body sites (11 from blood, 8 from catheter tips, and 1 from ascites), 154 (75.1%) from respiratory sites, 18 (8.8%) from skin or wound pus, 5 (2.4%) from urine, and 8 (3.9%) from other sites. The mean age was 6 years. The common underlying diseases were haematological or oncological diseases (n = 15, 28.8%), neonatal disorders (6, 11.5%), cyanotic congenital heart diseases (10, 19.2%), neurology disorders (12, 23.1%), and gastrointestinal tract disorders (3, 5.8%). Seventeen patients (32.7%) had received major surgery, and 48 (92.3%) had used ventilators. Fourteen patients (26.9%) had neutropenia and 46 (88.5%) had used broad-spectrum antibiotics. There were 31 patients (59.6%) with suspected or proven MDRAB infections, including sepsis (9 patients), pneumonia (19), wound infections (3), urinary tract infections (2), peritonitis (1), and perineal infection (1). Seven (77.8%) of the 9 sepsis patients died. The overall mortality rate was 42.3% (22 cases). CONCLUSIONS: The threat of MDRAB has been recognized in our hospital for several years. Host defense deficiencies, prolonged intensive care unit hospitalizations, and prior broad-spectrum antibiotic use play a major role in MDRAB infection and colonization.

Epidemiology of respiratory syncytial virus infection in northern Taiwan, 2001-2005 -- seasonality, clinical characteristics, and disease burden.

BACKGROUND AND PURPOSE: Respiratory syncytial virus (RSV) is an important pathogen in children less than 2 years old. However, there is limited epidemiological data about RSV infection in Taiwan. This study aimed to investigate the clinical, epidemiological, virological, and economical aspects of RSV infections in Taiwan. METHODS: We collected data of children with positive RSV respiratory specimens at the Laboratory of Virology, National Taiwan University Hospital, between January 2001 and December 2005. Medical charts were reviewed retrospectively. RESULTS: 892 children in whom acute bronchiolitis was the predominant diagnosis (60.7%) were enrolled. Compared with those without underlying disease (n = 630), children with underlying disease (n = 262) were older (11 vs 9 months), required longer oxygen therapies (7 vs 4 days), were more likely to have lower respiratory tract involvement (96.2% vs 92.3%) and intensive care unit stays (49.0% vs 9.4%), endotracheal intubations (21.0% vs 2.0%), ribavirin use (35.0% vs 1.4%), and had higher medical costs (US$ 1250 vs 688), and nosocomial infection (24.8% vs 1.0%). Compared with those without endotracheal intubation (n = 824), cases requiring endotracheal intubation (n = 68) had higher rates of underlying diseases (80.9% vs 25.1%), especially congenital heart diseases (45.6% vs 8.1%), chronic lung disease (13.2% vs 3.2%) and neurological disorders (17.6% vs 3.5%). There was a biennial pattern with peaks in the spring and fall. Medical cost was estimated to be US$ 250,000 annually in our hospital. CONCLUSION: In children with underlying diseases, RSV infection is associated with significant morbidity, and even mortality. Nosocomial infections appear to be an important cause of RSV transmission. The seasonality of RSV infections in Taiwan showed a biennial pattern with peaks in spring and fall.

Clinical features and complications of viridans streptococci bloodstream infection in pediatric hemato-oncology patients.

BACKGROUND AND PURPOSE: Viridans streptococci (VS) are part of the normal flora of humans, but are fast emerging as pathogens causing bacteremia in neutropenic patients. The clinical features, outcomes, and antibiotic susceptibilities of VS bloodstream infections in children with hemato-oncological diseases are reported in this study. METHODS: A retrospective chart review of pediatric patients (< or =18 years) diagnosed with VS infections between January 1998 and December 2004 was conducted at the National Taiwan University Hospital. RESULTS: Among the 26 episodes noted in 25 pediatric patients, the incidence rate of VS bacteremia was found to be significantly higher in pediatric patients with acute myeloid leukemia compared with other hemato-oncological conditions. Most of the patients had profound neutropenia related to chemotherapy for a median of 5 days on the day of positive blood culture. Eight of the 25 patients had undergone stem cell transplantations. Streptococcus mitis was the most common bloodstream isolate and only 12 (44%) of the 27 isolated strains of VS were penicillin-susceptible. Empirical antibiotic treatments were not effective in half of the episodes, but did not affect overall mortality. Isolated bacteremia (63%) and pneumonia (22%) were the two leading clinical presentations. Complications were recognized more frequently in patients with pneumonia. Hypotension and mechanical ventilation each developed in 8 patients (31%). The overall mortality rate was 23%. CONCLUSIONS: Penicillin non-susceptible VS infection has emerged as a threat in children with hemato-oncological diseases, especially those with acute myeloid leukemia. S. mitis is the most common spp. of VS causing bacteremia in children and is associated with serious complications. The development of pneumonia resulted in clinical complications and higher mortality. Empirical antibiotic treatments with activity against the infecting strains did not reduce the overall mortality rate in this study.

Hand, foot and mouth disease complicated with central nervous system involvement in Taiwan in 1980-1981.

Sixteen cases from the 1980-1981 Taiwan outbreak of hand, foot and mouth disease (HFMD) associated with central nervous system involvement were identified: nine had polio-like syndrome, four had encephalitis or encephalomyelitis, one had cerebellitis, and two had aseptic meningitis. They all had fever, five (31%) had documented myoclonic jerk, and 15 (93%) had HFMD. Their mean blood leukocyte count was 12,490/microL, and five (31%) had leukocytosis (> 15,000/microL); mean cerebrospinal fluid (CSF) leukocyte count was 156/microL, CSF protein was 57 mg/dL and CSF glucose was 57 mg/dL. Two patients with HFMD plus encephalitis died within 1 day of hospitalization, and one of them had acute cardiopulmonary failure mimicking myocarditis. Twenty years later, at least one male patient had sequelae of polio-like syndrome and was therefore exempted from military service. Clinical severity was comparable to the 1998 EV71 epidemic.

Detection of human metapneumovirus in hospitalized children with acute respiratory tract infection using real-time RT-PCR in a hospital in northern Taiwan.

BACKGROUND/PURPOSE: Human metapneumovirus (hMPV) is a newly discovered respiratory pathogen. This prospective hospital-based study investigated the clinical role and features of hMPV in Taiwan. METHODS: Respiratory specimens collected from hospitalized children with acute respiratory tract infection between September 1, 2003 and April 10, 2005 were screened for metapneumovirus using real-time reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: During the study period, 930 specimens were obtained from 926 hospitalized children. After exclusion of 200 cases due to lack of clinical evidence of airway infection or diseases with known etiology, 726 were included in the analysis. Among these, 33 children had a positive result for hMPV infection. The majority of these patients were admitted during spring and early summer. Twenty-one (63.6%) were younger than 2 years of age. hMPV accounted for 13.3% of respiratory infections occurring between the ages of 18 and 24 months and was as common a respiratory pathogen as respiratory syncytial virus (RSV) in that age group. The 11 patients (33.3%) with underlying diseases had a similar disease course to those without underlying diseases. A co-pathogen was found in 11 patients (33.3%). Infected children between 2 and 5 years of age had significantly higher titers of hMPV in their respiratory specimens (103.88 copies/microL) than children younger than 2 years (102.26 copies/microL) (p = 0.013) and children older than 5 years (102.25 copies/microL) (p = 0.005). hMPV positive cases were significantly older than those with RSV infection (p = 0.002) and had a shorter duration of hospitalization (p = 0.001), fewer days of oxygen use (p = 0.001) and higher levels of C-reactive protein (p = 0.004). CONCLUSION: Metapneumovirus circulates in children in northern Taiwan during spring and early summer. hMPV was the most common respiratory pathogen in children aged between 18 and 24 months hospitalized with acute respiratory tract infection. Real-time RT-PCR is a sensitive method for investigating the epidemiology and diseases associated with hMPV.

Disease burden and related medical costs of rotavirus infections in Taiwan.

BACKGROUND: The disease burden and associated medical costs of rotavirus infections in inpatient and outpatient sectors in Taiwan were examined in anticipation of the availability of new rotavirus vaccines. METHODS: The yearly national case number and medical costs for all for inpatients and outpatients with acute gastroenteritis (AGE) were extracted from the Bureau of National Health Insurance database in Taiwan according to ICD-9-CM codes. A retrospective study was also performed using records of children with AGE seen at three hospitals in Taiwan in 2001 to identify laboratory confirmed rotavirus infection cases. The annual incidence and related medical costs of AGE due to rotavirus infection were then estimated. RESULTS: Children <5 years old comprised 83.6% of inpatient and 62.0% of outpatient pediatric AGE cases in Taiwan in 2001. Rotavirus was the most common agent detected among AGE patients in this age group in the three hospitals, and was detected in 32.9% (221/672) of inpatient and 24% (23/96) of outpatient stool specimens tested for microbial etiologies. An estimated 277,400 to 624,892 cases of rotavirus infections sought medical care in Taiwan in 2001, equaling one in 2 to 5 children <5 years old required medical care due to rotavirus infection. The incidence of hospitalization due to rotavirus infections was 1,528-1,997/100,000 for children <5 years old. The total associated medical costs due to rotavirus infection were estimated at US $10-16 millions in Taiwan in 2001. Although the per-capita medical cost of rotavirus infection was lower in Taiwan than in the United States or Hong Kong, the personal economic burden was similar among the three places when normalized for gross national incomes per capita. CONCLUSION: Infections caused by rotavirus constitute an important human and economic burden among young children in Taiwan. A safe and effective vaccine is urgently needed.

Survey of pertussis in patients with prolonged cough.

BACKGROUND AND PURPOSE: Pertussis is an acute respiratory tract illness resulting from Bordetella pertussis. Widespread use of pertussis vaccine over the past 50 years has decreased the incidence of pertussis. The incidence of pertussis in adolescents and adults has increased in many areas of the world. This study aimed to evaluate the etiologic role of B. pertussis in patients with prolonged cough in Taiwan. METHODS: Patients with cough lasting for more than 1 week were recruited. Nasopharyngeal swabs were taken for culture of B. pertussis and detection of nucleic acid of B. pertussis by polymerase chain reaction. Serum samples were collected in a subset of patients for assay of immunoglobulin G and immunoglobulin A antibodies against pertussis toxin. RESULTS: In total, 111 patients were recruited. Thirty-three patients agreed to have their serum samples taken and tested. Eight patients had evidence of acute infection with B. pertussis; among them, 1 was diagnosed by polymerase chain reaction and 7 by serology. Older subjects were more likely to suffer from pertussis than younger subjects. The incidence of pertussis in patients with prolonged cough was 7.2%. However, the rate could have been as high as 21% in those with serum samples tested. CONCLUSIONS: We conclude that pertussis is a prevalent disease in Taiwan, especially in adolescents and adults.

Stenotrophomonas maltophilia bacteremia in pediatric patients-- a 10-year analysis.

BACKGROUND AND PURPOSE: Stenotrophomonas maltophilia bacteremia is an important cause of mortality among immunocompromised children. However, there has been little information concerning S. maltophilia bacteremia in the pediatric population. METHODS: We reviewed the drug susceptibility of bloodstream isolates of S. maltophilia and medical charts of S. maltophilia bacteremia patients less than 18 years old at the Department of Pediatrics, National Taiwan University Hospital from January 1993 to June 2003. The risk factors associated with mortality of the patients with S. maltophilia bacteremia were analyzed. RESULTS: In total, 32 episodes (31 patients) of S. maltophilia bacteremia were reviewed. The average rate of nosocomial bloodstream infection was 8.3 episodes per 100,000 patient-days, and an average of 6.4% of them were caused by S. maltophilia. Malignancy was the most common underlying disease (32%). Six episodes of S. maltophilia bacteremia had soft tissue involvement, and only 1 of them underwent surgical intervention and survived. These 32 isolates were most susceptible to trimethoprim-sulfamethoxazole (91%), and no obvious increase in multidrug resistance was noted in the previous 10 years. The crude mortality rate was 40.6%. Malignancy, failure to remove central venous catheter, and ineffective antibiotic treatment were significant risk factors for mortality. CONCLUSIONS: Early and effective antimicrobial therapy and removal of central venous catheter as soon as possible are vital for the successful management of S. maltophilia bacteremia.