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A cluster of acute respiratory illnesses involving 12 inpatients and 3 healthcare workers occurred in a psychiatric ward. Eight of them were identified as HRV-A21. Fever and cough were the most common symptoms. The study also provides further evidence of the impact of HRV on lower respiratory tract illness.

BACKGROUND We conducted a longitudinal survey for methicillin-resistant Staphylococcus aureus (MRSA) carriage in nursing homes and long-term care facilities (LTCFs) in northern Taiwan. METHODS From July 2016 to February 2017, healthcare workers and residents in four institutions were enrolled. One swab sample from nares and another swab sample from umbilicus were obtained from each participant for detection of MRSA at enrolment and then follow-up samples were collected every two months for additional three times if feasible. RESULTS We enrolled a total of 194 participants, including 127 residents and 67 healthcare workers. MRSA colonization rates were 23.2%, 22.8%, 20.7% and 18.6% at enrolment, the 2-, 4-, and 6-month follow-up survey, respectively, and the cumulative colonization rate was 40.2%. The MRSA detection rate was significantly higher at Institution 2 (70.7%) than that at other three institutions (25.7% ∼ 35%) (p

Appropriate mitigation strategy to minimize enterovirus (EV) transmission among children is essential to control severe EV epidemics. Scientific evidence for the effectiveness of case isolation and class suspension is lacking.EV-infected children ≤ eight years are asked to stay at home for seven days. Classes were suspended for seven days if there are more than two classmates having an onset of herpangina or hand, foot, and mouth disease in one classroom within one week. Study subjects are divided into two groups, group A with class suspension for one week and group B without class suspension.Among 4153 reported EV-infected children from 1085 classes in May and June, 2015 were enrolled. Median incidence of EV infection in a class was 7% (range 3% -60%). The incidence was higher in group A (median 14%, range 3-60%) than that in group B (median 6%, range 3-80%) (P 0.01). The median incidence is highest in day care center (20%), followed by kindergarten (8%), and primary school (4%) (P 0.01). Most secondary cases in group A appeared within seven days after the disease onset of index case in the same class. The incidence of EV infection remained low and was similar between the two groups eight days and beyond after the disease onset of index cases.Targeted class suspension for seven days with case isolation for seven days is an effective measure to mitigate transmission of EV infection in children.

Background/purpose: Acute gastroenteritis (AGE) remains a significant health issue in children. The worldwide evolution of pediatric AGE pathogens had been recorded since the introduction of rotavirus vaccine. Ten years after the rotavirus vaccine was introduced to the private sectors in Taiwan, a nationwide study was conducted to elucidate the epidemiological changes among major AGE pathogens. Methods: From January 2014 to December 2017, children younger than 5 years old, hospitalized with AGE at 10 hospitals across Taiwan were enrolled. Stool specimens were tested for Salmonella spp., Campylobacter spp., Clostridiodes difficile, norovirus, and rotavirus by polymerase chain reaction (PCR). The epidemiological and clinical information was collected. Results: Enteric pathogen were detected in 1983 (42.2%) of 4700 subjects, with Salmonella spp. (12.5%) being the leading cause of AGE, followed by norovirus (11.2%), rotavirus (8.7%), C. difficile (4.2%), Campylobacter spp. (1.0%), and a mixture of at least 2 of 5 above-mentioned pathogens (4.6%). The case distributions varied across different regions. In eastern Taiwan, rotavirus (21/131, 16.0%) remained the most common pathogen detected. The rotavirus vaccine uptake rate is significantly lower in patients with rotavirus AGE. Besides, rotavirus AGE frequently occurred in children with foreign parent(s), Taiwanese indigenous people, and those with the household monthly income

Importance Although various computational approaches have been proposed for pathogen detection, no artificial intelligence (AI)-assisted antibiotic susceptibility test (AST) system has been robustly validated and truly deployed in a clinical laboratory in real-world settings. Consequently, the clinical impact of this type of medical AI system remains unknown.Objective To evaluate the clinical impact of an AI-assisted AST prediction system deployed in a clinical laboratory.DesignThe AI-assisted AST prediction system XBugHunter was extensively validated (internal validation, time-wise validation, and independent testing) using data collected between May 22, 2013, and June 30, 2019. The clinical impact was evaluated based on a prospective observation during the deployment phase, which was from February 1, 2020, to September 30, 2020.Setting Data were collected from two tertiary medical centers in Taiwan, and the AI system was deployed in a tertiary medical center.Participants A total of 90,064 consecutive patients with ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) infection were included in the development and validation study. During the deployment, a prospective observational cohort of 155 consecutive patients with Staphylococcus aureus bacteremia (SAB) was analyzed, whereas the historical control cohort included 455 patients.Exposures AST prediction from XBugHunter.Main Outcomes and Measures The diagnostic performance of XBugHunter was evaluated during the validation study. The clinical impact was evaluated in terms of the reduction in inappropriate antibiotic prescriptions, AST turnaround time, and mortality rate of SAB during the deployment.Results In the deployment, the predictive sensitivity and specificity for S. aureus (oxacillin) by XBugHunter were 0.95 (95% CI, 0.82–0.98) and 0.97 (95% CI, 0.94–0.99), respectively. The turnaround time reduction in the reporting of the AST results of SAB was 34.06 h. Death within 28 days was the outcome in 21 of the 155 SAB patients (13.55%) in the XBugHunter intervention group, which was significantly lower than the 28-day mortality rate (17.58% [80/455]) in the historical control cohort in 2019 without XBugHunter (p = 0.042). Regarding the antibiotic prescriptions, 45.16% [70/155] of the SAB patients had a change in their empirical antibiotics based on the predicted AST results. Totally, 114.77 defined daily doses of inappropriate antibiotics were avoided in treating SAB by deploying XBugHunter.Conclusions and Relevance This work has demonstrated the clinical impact of XBugHunter through extensive validation protocols. Additionally, among the patients with SAB, XBugHunter can prevent inappropriate antibiotic use, and this adjustment in antibiotic treatment can yield a lower mortality rate.

In 2006, two rotavirus vaccines were licensed in Taiwan but were not added to the national immunization schedule. National Health Insurance data from 2003 through 2017 were used to compare rotavirus-associated pediatric hospitalizations before and after vaccine introduction. Rotavirus hospitalization rates among children < 5 years of age significantly declined by 24% (95% confidence interval [CI] 23 - 25%) in post-vaccine compared to pre-vaccine rotavirus seasons. Rotavirus hospitalization rates declined by 42% (95% CI 39 - 44%) among infants < 12 months of age, and by 38% (95% CI 36 - 40%) among children 12 - 23 months of age. These findings suggest that, despite not being included in the national immunization schedule, rotavirus vaccines had a measurable impact on reducing rotavirus hospitalization burden among Taiwanese children.

Background: Norovirus is a common acute gastroenteritis (AGE) pathogen across all age groups worldwide, which is difficult to differentiate from other pathogens. This study aimed to understand the clinical characteristics and risk factors of norovirus gastroenteritis among children in Taiwan. Methods: A prospective AGE surveillance study was conducted in children aged ≤5 years who were hospitalized in 10 major hospitals in Taiwan between 2014 and 2017. The non-AGE control group included healthy children who were matched based on age, gender, season, and geographic area. Results: Overall, 674 norovirus gastroenteritis patients were enrolled. Fever (p

Heterologous prime-boost COVID-19 vaccine strategy may facilitate mass COVID-19 immunization. We reported early immunogenicity and safety outcomes of heterologous immunization with a viral vector vaccine (ChAdOx1) and a spike-2P subunit vaccine (MVC-COV1901) in a participant-blinded, randomized, non-inferiority trial (NCT05054621). A total of 100 healthy adults aged 20–70 years having the first dose of ChAdOx1 were 1:1 randomly assigned to receive a booster dose either with ChAdOx1 (n = 50) or MVC-COV1901 (n = 50) at an interval of 4–6 or 8–10 weeks. At day 28 post-boosting, the neutralizing antibody geometric mean titer against wild-type SARS-CoV-2 in MVC-COV1901 recipients (236 IU/mL) was superior to that in ChAdOx1 recipients (115 IU/mL), with a GMT ratio of 2.1 (95% CI, 1.4 to 2.9). Superiority in the neutralizing antibody titer against Delta variant was also found for heterologous MVC-COV1901 immunization with a GMT ratio of 2.6 (95% CI, 1.8 to 3.8). Both spike-specific antibody-secreting B and T cell responses were substantially enhanced by the heterologous schedule. Heterologous boosting was particularly prominent at a short prime-boost interval. No serious adverse events occurred across all groups. The findings support the use of heterologous prime-boost with ChAdOx1 and protein-based subunit vaccines.

Background Severe illness can occur in young children infected with certain types of enteroviruses including echovirus 11 (Echo11) and coxsackievirus B5 (CoxB5). The manifestations and outcomes of Echo11 and CoxB5 diseases across all ages of children remained not comprehensively characterized in Taiwan. Methods Culture-confirmed Echo11 (60 patients) or CoxB5 (65 patients) infections were identified in a hospital from 2010 to 2018. The demographics, clinical presentations, laboratory data and outcomes were abstracted and compared between the two viruses infections. Results Echo11 and CoxB5 was respectively identified in 7 (77.8%) and 2 (22.2%) of 9 calendar years. The median age of all patients was 15 months (range, 1 day–14.5 years). For infants ≤3 months old, Echo11 (23 cases) was associated with higher incidence of aseptic meningitis (35% versus 0%, P = 0.003), and a lower rate of upper respiratory tract infections (URI) (22% versus 65%, P = 0.004) compared to CoxB5 (20 cases) infections. For patients >3 months old, URI was the cardinal diagnosis (60%) for both viruses. Aseptic meningitis was also more commonly identified in elder children with Echo11 infections (27% versus 11%), though with marginal significance (P = 0.07). Acute liver failure was identified in four young infants with Echo11 infections including one neonate dying of severe sepsis and myocarditis. All patients with CoxB5 infections recovered uneventfully. Conclusion Aseptic meningitis, sepsis-like illness and acute liver failure were more commonly identified in children with Echo11 than those with CoxB5 infections, suggesting greater neurological tropism and virulence toward Echo11.

Introduction To combat COVID-19, scientists all over the world have expedited the process of vaccine development. Although interim analyses of clinical trials have demonstrated the efficacy and safety of COVID-19 vaccines, a serious but rare adverse event, thrombosis with thrombocytopenia syndrome (TTS), has been reported following COVID-19 vaccination. Areas covered This review, using data from both peer-reviewed and non-peer-reviewed studies, aimed to provide updated information about the critical issue of COVID-19 vaccine-related TTS. Expert opinion : The exact epidemiological characteristics and possible pathogenesis of this adverse event remain unclear. Most cases of TTS developed in women within 2 weeks of the first dose of vaccine on the receipt of the ChAdOx1 nCoV-19 and Ad26.COV2.S vaccines. In countries with mass vaccination against COVID-19, clinicians should be aware of the relevant clinical features of this rare adverse event and perform related laboratory and imaging studies for early diagnosis. Non-heparin anticoagulants, such as fondaparinux, argatroban, or a direct oral anticoagulant (e.g. apixaban or rivaroxaban) and intravenous immunoglobulins are recommended for the treatment of TTS. However, further studies are required to explore the underlying mechanisms of this rare clinical entity. Plain language summary What is the context?Thrombosis with thrombocytopenia syndrome (TTS) usually develops within 2 weeks of the first doses of the ChAdOx1 nCoV-19 and Ad26.COV2.S COVID-19 vaccines.TTS mainly occurs in patients aged 50 × 109/L and there is no serious bleeding. Intravenous immunoglobulins and glucocorticoids may help increase the platelet count within days and reduce the risk of hemorrhagic transformation when anticoagulation is initiated.What is the impact?TTS should be a serious concern during the implementation of mass COVID-19 vaccination, and patients should be educated about this complication along with its symptoms such as severe headache, blurred vision, seizure, severe and persistent abdominal pain, painful swelling of the lower leg, and chest pain or dyspnea. The incidence of TTS is low; therefore, maintenance of high vaccination coverage against COVID-19 should be continued.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has substantially impacted human health globally. Spike-specific antibody response plays a major role in protection against SARS-CoV-2. Here, we demonstrated that acute SARS-CoV-2 infection elicits rapid and robust spike-binding and ACE2-blocking antibody responses, which wane approximately 11 months after infection. Serological responses were found to be correlated with the frequency of spike-specific memory B cell responses to natural infections. Further, significantly higher spike-binding, ACE2-blocking, and memory B cell responses were detected in patients with fever and pneumonia. Spike-specific antibody responses were found to be greatly affected by spike mutations in emerging variants, especially the Beta and Omicron variants. These results warrant continued surveillance of spike-specific antibody responses to natural infections and highlight the importance of maintaining functional anti-spike antibodies through immunization.ImportanceAs spike protein-specific antibody responses play a major role in protection against SARS-CoV-2, we examined the spike-binding and ACE2-blocking antibody responses in SARS-CoV-2 infection at different time points. We found robust responses following acute infection, which waned approximately 11 months after infection. Further, the serological responses were correlated with the frequency of spike-specific memory B cell responses to natural infections. Patients with fever and pneumonia showed significantly stronger spike-binding, ACE2-blocking antibody, and memory B cell responses. Moreover, the spike-specific antibody responses were substantially affected by the emerging variants, especially the Beta and Omicron variants. These results warrant continued surveillance of spike-specific antibody responses to natural infections and highlight the importance of maintaining functional anti-spike antibodies through immunization.

Background: Norovirus (NoV) and rotavirus (RV) are among the most common causes of acute gastroenteritis (AGE) of all ages worldwide. There have been scanty reports of the epidemiology data of NoV AGE from clinical virologic laboratory. Methods: All stool specimens sent to the virologic laboratory in a medical center in Taiwan for detection of both NoV (by reverse transcription-polymerase chain reaction) and RV (by enzyme immunoassay) from 2013 to 2018 were included for analysis. Results: A total of 15,991 specimens, annually ranging from 2430 in 2017–2915 in 2013, were included. 48.0% and 73.1% of the specimens were obtained from children aged

Moraxella catarrhalis is a common, potential pathogen colonizing the respiratory tract in children. However, there is little information regarding the determinants of M. catarrhalis colonization and disease development.A population-based cohort study was conducted to collect nasopharyngeal swabs from children aged 1, 2, 4, 6, 12, 18, 24, 36, and 60 months for the detection of four common respiratory tract pathogens, including Staphylococcus aureus, M. catarrhalis, Streptococcus pneumoniae, and Haemophilus influenzae. Questionnaires on breastfeeding status were administered during each visit.A total of 921 children were enrolled between 2012 and 2018. S.aureus was the most common pathogen, although the rates declined during the initial 18 months of life; in contrast, the other three pathogens increased during the first 5 years of life. M. catarrhalis was the second most common colonizing pathogen in all age groups, with prevalence ranging from 0.8% (7/842) at one month to 20.4% (33/162) at 60 months of age. Breastfed children (odds ratio [OR]: 0.56; 95% confidence interval [CI]: 0.35-0.92; P = 0.02) had a lower potential for M. catarrhalis carriage; however, infants with a longer duration of exclusive breastfeeding (OR: 1.12; 95% CI: 1.01-1.25; P = 0.04), especially12 months of age, had a higher rate of M. catarrhalis carriage.Breastfeeding should be promoted because it may be correlated with a lower risk of M. catarrhalis carriage. However, an extended period of exclusive breastfeeding may be positively associated with M. catarrhalis colonization.

Background Two rotavirus vaccines (RV1 and RV5) are available on the private market in Taiwan, not included in national immunization program. Scanty reports evaluated the rotavirus vaccine effectiveness (VE) in Asian countries. Methods From February 2014-July 2017, we conducted a prospective case-control study in ten hospitals in Taiwan. Case-patients included children aged 8–59 months, and hospitalized with laboratory-confirmed rotavirus acute gastroenteritis (AGE). For each case patient, up to four controls, rotavirus-negative AGE or non-AGE illnesses, respectively, were matched by gender, age and enrolled date. Vaccination history was confirmed through vaccination card or hospital record. VE was calculated as (1 − odds ratio of vaccination) × 100%. Results Totally 4248 AGE patients and 2242 non-AGE controls were enrolled. A total of 330 case-patients with rotavirus AGE, 1226 rotavirus-negative AGE controls and 1122 non-AGE controls were included for analysis. Unvaccinated rate was 85.15% for rotavirus-positive cases, 42.9% for rotavirus-negative controls, and 34.31% for non-AGE controls. VE of two-dose RV1 was 84.9% (95% confidence interval [CI]:77.7%, 90.1%) for rotavirus-negative AGE and 88.9% (95% CI: 83.4%, 92.8%) for non-AGE controls, while VE of three-dose RV5 was 92.5% (95% CI: 85.1%, 96.7%) and 96.4% (95% CI: 91.9%, 98.6%), respectively. For respective vaccine, VEs were not significantly different in term of rotavirus genotypes. VEs of both vaccines declined Conclusions Both vaccines provided excellent and sustained protection against rotavirus AGE hospitalization in children in Taiwan, but the effectiveness declined slightly in children aged three years.

By the request of the Minister of Health and Welfare, NHRI Biobank was assigned to establish a COVID-19 biobank in early Feb, 2020 to collect COVID-19 patients' blood samples for Taiwan researchers and industries in an emergent way. It was set up in less than 3 weeks and quickly opened for application. By August 5, 2020, this COVID-19 biobank has collected 165 blood samples of 110 patients from more than 10 hospitals across north, middle and south part of Taiwan, including both COVID-19 (+) and (-) pneumonia patients. This biobank can provide applicants with biosamples, such as serum, DNA and RNA, and also the clinical and genomic data, so as to accelerate the COVID-19 treatment and prevention research in Taiwan. This COID-19 biobank already received 15 applications. It has become the most important research resource for the COVID-19 pandemic in Taiwan, including new screening reagents, disease mechanism, the variable human responses and epidemic preventions. Since it is publicly available for both academic and industrial applicants.

This study analyzed the clinical features and molecular characteristics of methicillin-susceptible Staphylococcus aureus (MSSA) ocular infections in Taiwan and compared them between community-associated (CA) and health-care-associated (HA) infections. We collected S. aureus ocular isolates from patients at Chang Gung Memorial Hospital between 2010 and 2017. The infections were classified as CA or HA using epidemiological criteria, and the isolates were molecularly characterized using pulsed-field gel electrophoresis, multilocus sequence typing, and Panton-Valentine leukocidin (PVL) gene detection. Antibiotic susceptibility was evaluated using disk diffusion and an E test. A total of 104 MSSA ocular isolates were identified; 46 (44.2%) were CA-MSSA and 58 (55.8%) were HA-MSSA. Compared with HA-MSSA strains, CA-MSSA strains caused a significantly higher rate of keratitis, but a lower rate of conjunctivitis. We identified 14 pulsotypes. ST 7/pulsotype BA was frequently identified in both CA-MSSA (28.3%) and HA-MSSA (37.9%) cases. PVL genes were identified in seven isolates (6.7%). Both CA-MSSA and HA-MSSA isolates were highly susceptible to vancomycin, teicoplanin, tigecycline, sulfamethoxazole–trimethoprim, and fluoroquinolones. The most common ocular manifestations were keratitis and conjunctivitis for CA-MSSA and HA-MSSA, respectively. The MSSA ocular isolates had diverse molecular characteristics; no specific genotype differentiated CA-MSSA from HA-MSSA. Both strains exhibited similar antibiotic susceptibility.

Staphylococcus aureus is an important pathogen for keratitis, a vision-threatening disease. We aimed to investigate the genotyping, antibiotic susceptibility, and clinical features of S. aureus keratitis, and to explore the possible role of Panton–Valentine leucocidin (PVL), a major virulence factor of S. aureus. We recruited 49 patients with culture-proven S. aureus keratitis between 2013 and 2017 at Chang Gung Memorial Hospital, Taiwan. PVL gene, multilocus sequence type (MLST), staphylococcal cassette chromosome mec (SCCmec), and pulsed-field gel electrophoresis (PFGE) were performed. Antibiotic susceptibility was verified using disk diffusion/E test. There were 49 patients with S. aureus keratitis; 17 (34.7%) were caused by methicillin-resistant S. aureus (MRSA) and 9 (18.4%) isolates had PVL genes. The predominant genotyping of MRSA isolates was CC59/PFGE type D/SCCmec VT/PVL (+). All methicillin-sensitive S. aureus (MSSA) and approximately 60% MRSA were susceptible to fluoroquinolones. No significant differences in clinical features, treatments, and visual outcomes were observed between MRSA/MSSA or PVL(+)/PVL(−) groups. In Taiwan, approximately one third of S. aureus keratitis was caused by MRSA, mainly community-associated MRSA. Although MRSA isolates were more resistant than MSSA, clinical characteristics were similar between two groups. Fluoroquinolones could be good empiric antibiotics for S. aureus keratitis.

Taiwan commenced a national catch-up immunization program with a 13-valent pneumococcal conjugate vaccine (PCV13) in 2013 for children aged 2-5 years old and in 2014 for children aged 1-5 years old. However, real-world nationwide evidence of both the direct protection and indirect protection of all-cause pneumonia and pneumococcal pneumonia has been scarce, especially among high-risk populations, defined as patients with chronic diseases or immunosuppression. The aim of this study was to examine the impact of the national PCV13 catch-up program on all-cause pneumonia and pneumococcal pneumonia among overall and high-risk populations using interrupted time series analysis.Using the National Health Insurance Research Database (NHIRD) from January 2001 to December 2015, we assessed the impact of this catch-up program by interrupted time-series analyses age-stratified (0-1, 2-4, 5-9, 10-17, 18-34, 35-49, 50-64, 65 + years old) incidence of pneumococcal pneumonia and all-cause pneumonia (100,000 person-quarter) among the overall and high-risk populations.The impact of this program was most profound on the incidence of pneumococcal pneumonia in children aged 2-4 years old (level change -10.56 per 100,000 person-quarters, p = 0.04; trend change -2.93, p less than 0.01). Indirect protection among unvaccinated children (0-1 years old: trend change -1.19, p = 0.01; 5-9 years old: trend change -1.04, p = 0.03; 10-17 years old: level change -1.42 per 100,000 person-quarters, p = 0.03) was also found. The incidence of all-cause pneumonia also decreased in children aged 2-4 (level change -234.91 per 100,000 person-quarter, p = 0.058) and 5-9 years old (level change -173.96 per 100,000 person-quarter, p = 0.0424). However, we did not find a significant impact among most high-risk populations.Our study suggests that the introduction of this catch-up program with PCV13 was associated with significant declines in the incidence of pneumococcal pneumonia and all-cause pneumonia in vaccinated children, and indirect protection from the program was also found in unvaccinated children.

Background Methicillin-resistant Staphylococcus aureus (MRSA) has been an important nosocomial pathogen in our neonatal units since 1990s. To understand the longitudinal changing molecular epidemiology of these MRSA isolates, we conducted this study. Materials From 2003 to 2018, we collected clinical MRSA isolates from 536 infants hospitalized at neonatal units of a medical center in northern Taiwan. First isolate from each infant was characterized. Results The case/isolate number ranged from 7 cases/isolates (the lowest) in 2010 to 71 cases/isolates (the highest) in 2004. Of the 536 isolates, a total of 15 pulsotypes were identified. Three major clones were identified and characterized as sequence type (ST) 239/pulsotype A/staphylococcal chromosomal cassette (SCC) mec III/Panton-Valentine leukocidin (PVL)-negative, accounting for 22.2% of the isolates, ST59/pulsotype C/SCCmec IV/PVL-negative, accounting for 34.3% and ST59/pulsotype D/SCCmec VT/PVL-positive, accounting for 30.0%. The first clone (hospital strains) dominated in the first two years, and became weakened from 2005 through 2016. Clonal complex (CC) 59 (combined the second and third clones) dominated (>50% of the isolates) from 2005 through 2018. One community clone (ST573) demonstrated a marked increase since 2007 and vanished abruptly since 2010. Several minor MRSA clones emerged after 2010. Conclusion The molecular epidemiology of MRSA isolates in our neonatal units from 2003 to 2018 revealed that an epidemic as well as endemic hospital clone of ST239 dominated before 2005 and was replaced by the local community clone of CC59 thereafter.

Influenza A virus mutates rapidly, allowing it to escape natural and vaccine-induced immunity. Neuraminidase (NA) is a surface protein capable of cleaving the glycosidic linkages of neuraminic acids to release newly formed virions from infected cells. Genetic variants within a viral population can influence the emergence of pandemic viruses as well as drug susceptibility and vaccine effectiveness. In the present study, 55 clinical specimens from patients infected with the 2009 pandemic influenza A/H1N1 virus, abbreviated as A(H1N1)pdm09, during the 2015-2016 outbreak season in Taiwan were collected. Whole genomes were obtained through next-generation sequencing. Based on the published sequences from A(H1N1)pdm09 strains worldwide, a mixed population of two distinct variants at NA position 151 was revealed. We initially reasoned that such a mixed population may have emerged during cell culture. However, additional investigations confirmed that these mixed variants were detectable in the specimens of patients. To further investigate the role of the two NA-151 variants in a dynamic population, a reverse genetics system was employed to generate recombinant A(H1N1)pdm09 viruses. It was observed that the mixture of the two distinct variants was characterized by a higher replication rate compared to the recombinant viruses harbouring a single variant. Moreover, an NA inhibition assay revealed that a high frequency of the minor NA-151 variant in A(H1N1)pdm09 was associated with a reduced susceptibility to NA inhibitors. We conclude that two distinct NA-151 variants can be identified in patient specimens and that such variants may increase viral replication and NA activity.

Background: Carriage of methicillin-resistant Staphylococcus aureus (MRSA) is associated with its transmission. International travels and massive gatherings may accelerate such transmission. MRSA carriage was surveyed among the attendees of two international medical conferences held in Taipei in 2010. Methods: A total of 209 attendees from 23 countries were recruited. Nasal specimens were collected from each volunteer and subjected to polymerase chain reaction (PCR) detection for MRSA. Molecular analysis, including pulsed-field gel electrophoresis, multilocus sequence typing (MLST), typing of staphylococcal cassette chromosome mec (SCCmec) and staphylococcal protein A (spa) genes, and detection of Panton-Valentine leukocidin (PVL) and sasX genes, was performed. Results: MRSA carriage was detected in 10 (4.8%) attendees from Vietnam (3/8, 37.5%), Korea (2/6, 33.3%), Japan (2/41, 4.9%), Philippines (2/52, 3.8%), and Bangladesh (1/4, 25.0%). The proportion of MRSA colonizers was significantly higher in the local hospital group compared to those from the other groups (3/17 vs. 7/192, p

Background/purpose: Staphylococcus aureus (S. aureus) causes diseases ranging from mild skin infections to invasive diseases. Carriage of S. aureus, including methicillin-resistant S. aureus (MRSA), is a significant risk factor for subsequent staphylococcal infection. Several studies discussed MRSA colonization in Taiwan, but mostly in northern Taiwan. This is the first study that estimates the prevalence of MRSA nasal colonization in healthy children and identifies the potential risk factors in central Taiwan. Methods: A total of 3144 healthy children aged 2–60 months who visited Taichung Veterans General Hospital (TCVGH) were screened for nasal S. aureus carriage from July 2005 to December 2010. Questionnaires included demographic information and potential risk factors for carriage of S. aureus were completed by parents/guardians. Results: Prevalence of MSSA and MRSA were 12.09% and 5.25%, respectively. The youngest group aged 2–6 months had the highest S. aureus carriage rate, and the carriage rate revealed a peak in summer. The nasal colonization of Streptococcus pneumoniae (S. pneumoniae) was a protective factor against S. aureus colonization. 85% of the MRSA colonizing isolates belonged to clonal complex 59/staphylococcal cassette chromosome type IV or VT, the local community clone in Taiwan. Conclusion: An increasing trend of MRSA nasal carriage rate in Taiwan had been brought forward, however, it was not observed in central Taiwan during the period of 2005–2010. We found a summer peak on both MRSA and MSSA carriages. Keywords: Central Taiwan, Children, Methicillin-resistant Staphylococcus aureus colonization

Community-acquired pneumonia (CAP) causes substantial morbidity and mortality in adults worldwide. The etiology of CAP often remains uncertain, and therapy is empirical. Thus, there is still room for improvement in the diagnosis of pneumonia.Adults aged20 years who presented at the outpatient or emergency departments of Linkou and Keelung Chang Gung Memorial Hospital with CAP were prospectively included between November 2016 and December 2018. We collected respiratory specimens for culture and molecular testing and calculated the incidence rates of CAP according to pathogens.Of 212 hospitalized adult patients with CAP, 69.3% were male, and the median age of the patients was 67.8 years. Bacterial pathogens were detected in 106 (50%) patients, viruses in 77 (36.3%), and fungal pathogens in 1 patient (0.5%). The overall detection rate (culture and molecular testing method) was 70.7% (n = 150). Traditional microbial culture yielded positive results in 36.7% (n = 78), molecular testing in 61.3% (n = 130). The most common pathogens were influenza (16.1%), followed by Klebsiella pneumoniae (14.1%), Pseudomonas aeruginosa (13.6%), human rhinovirus (11.8%), and Streptococcus pneumoniae (9.9%). Multiple pathogen co-infections accounted for 28.7% (n = 61), of which co-infection with K. pneumoniae and human rhinovirus comprised the largest proportion.Molecular diagnostic testing could detect 23.6% more pathogens than traditional culture techniques. However, despite the current diagnostic tests, there is still the possibility that no pathogen was detected.