Sudan virus disease - A quick review.

The recent Sudan virus disease (SVD) outbreak in Uganda is a reminder of threat from Filovirus diseases. Unlike Ebola virus disease, no effective antiviral and vaccine is available for SVD. The outbreak was declared over after 115 days, with 142 confirmed cases and case fatality rate of 39%, before any dose of candidate vaccine could be used on contacts. We provide a quick review of up-to-date information on the Uganda outbreak, summary of previous outbreaks, and detail the existing SVD treatment and vaccine candidates. Evolution of disease attributes and the impact on public health were also discussed. For high consequence infectious disease like SVD, it takes international collaboration to be better prepared for the next outbreak.

Epidemiology and risk factors of Japanese encephalitis in Taiwan, 2010-2022.

INTRODUCTION: Taiwan introduced a two-dose inactivated Japanese encephalitis (JE) mouse brain-derived (JE-MB) vaccine into routine childhood immunization in 1968, with booster vaccination implemented in 1974 and 1983. In 2017, JE-MB vaccine was replaced by a two-dose live-attenuated chimeric vaccine (JE-CV). After implementation of JE vaccination programs, JE cases have shifted from children to adults. In this study, we described the JE epidemiology and identify high-risk groups to further inform vaccine policy. METHODOLOGY/PRINCIPAL FINDINGS: We extracted data from Taiwan's notifiable disease surveillance database, vital statistics, and employment statistics from 2010 to 2022. Diagnosis of JE was confirmed by JE seroconversion, a four-fold increase in virus-specific antibodies, a positive JE viral nucleic-acid test, or JE virus isolation. From 2010 to 2022, a total of 313 cases of JE were diagnosed, resulting in an overall incidence rate of 0.10 cases per 100,000 person-years and a mortality rate of 0.006 per 100,000 population per year. Among these patients, 64% were male, and the median age was 51 years (range 0-82). Compared with people born in or after 1976 (vaccinated with four doses of JE-MB vaccine or two doses of JE-CV), those born in or before 1962 (unvaccinated) and those born during 1963-1975 (vaccinated with two or three doses of JE-MB vaccine) had a 4.2-fold (95% confidence interval [CI] 3.0-5.7) and 5.9-fold (95% CI 4.3-8.1) higher risk of JE, respectively. The relative risk of working in agriculture, forestry, fishing, or animal husbandry, compared to other occupations, was 5.0 (95% CI 3.5-7.0). CONCLUSIONS/SIGNIFICANCE: In Taiwan, individuals born before 1976 and those employed in agriculture, forestry, fishing, or animal husbandry had a higher risk of JE. We recommend JE vaccination for people in these high-risk groups who have not been fully vaccinated or have an unknown vaccination history.

Epidemiology of the first 100 cases of COVID-19 in Taiwan and its implications on outbreak control.

PURPOSE: To describe the epidemiology and outcome of the first 100 COVID-19 cases in Taiwan. METHODS: We included the first 100 patients with laboratory-confirmed SARS-CoV-2 infection in Taiwan. Demographic, clinical, epidemiological and laboratory data were extracted from outbreak investigation reports and medical records. RESULTS: Illness onset of the 100 patients was during January 11 to March 16, 2020. Twenty-nine (29%) had at least one underlying condition and ten (10%) were asymptomatic. Seventy-one were imported, including four clusters. Twenty-nine were locally-acquired, including four clusters. The median days from onset to report was longer in locally-acquired cases (10 vs 3 days). Three patients died (case fatality rate 3%) and all of them had underlying conditions. As of May 13, 2020, 93 had been discharged in stable condition; the median hospital stay was 30 days (range, 10-79 days). CONCLUSION: The first 100 cases of COVID-19 in Taiwan showed the persistent threat of imported cases from different countries. Even though sporadic locally-acquired disease has been identified, through contact investigation, isolation, quarantine and implementation of social distancing measures, the epidemic is contained to a manageable level with minimal local transmission.

Comparative epidemiology of influenza B by lineage in intensive care unit-admitted patients with complications: A nationwide study in Taiwan, 2013-2017.

BACKGROUND: We describe the relative proportions and epidemiological features of influenza B/Victoria and B/Yamagata, using data from nationwide surveillance systems. METHODS: We collected respiratory samples from outpatients with influenza-like illness (ILI) and intensive care unit (ICU)-admitted patients with complications (pulmonary or neurological complications, myocarditis/pericarditis or invasive bacterial infection) for virus isolation and lineage typing. Demographics, epidemiological features, and vaccination history from ICU-admitted patients with complications were analyzed. RESULTS: From July 2013-June 2017, 21% of 11517 influenza isolates were influenza B. B/Victoria was the predominant circulating strain in 2013-2014, accounted for 56% of all influenza B positive samples and B/Yamagata was predominant in 2014-2017 (82%, 69%, and 85%, respectively). Among all typed viruses, the proportion of B/Yamagata was higher among specimens from ICU-admitted patients with complications (77%, 154/199) than from ILI outpatients (66%, 276/418, p<0.005). Compared to B/Victoria, B/Yamagata infected ICU-admitted patients with complications were older, median age (71 vs. 59 years, p<0.05), had longer durations of hospitalization (15 vs. 7.5 days, p<0.05) and ICU stays (8.5 vs. 5.5 days, p<0.05). CONCLUSIONS: Two lineages of influenza B viruses co-circulate annually in Taiwan. Among ICU-admitted patients with complications, B/Yamagata causes more severe illness than B/Victoria.

Seasonal influenza prevention and control in Taiwan-Strategies revisited.

Influenza remains a serious public health threat in Taiwan. During 2017-18, Taiwan experienced two seasonal influenza epidemics caused by A/H3N2 and B, respectively. In addition to national influenza vaccination campaign, Taiwan Centers for Diseases Control and Infectious Disease Control Advisory Committee has multi-faceted strategies for seasonal influenza prevention and control to mitigate the risk of disease transmission among vulnerable groups and decrease influenza-related morbidity and mortality. In this article, we reviewed the key elements of the prevention and control strategies-enhanced influenza surveillance, antiviral drugs stockpile and management, critical care and medical resources reallocation, public risk communication and infection control measures. Given the complexity and challenging nature of controlling seasonal influenza epidemics, collaboration between health professionals is crucial to optimize the health of Taiwanese people.

Influenza A(H3N2) virus variants and patient characteristics during a summer influenza epidemic in Taiwan, 2017.

We report a summer influenza epidemic caused by co-circulation of multiple influenza A(H3N2) variants in clade 3C.2a. Compared with other clades, a putative clade 3C.2a.3a was more commonly isolated from severely ill patients; 3C.2a.4 was more commonly isolated in outbreak cases. Time from vaccination to illness onset was significantly shorter in severely ill patients infected with clade 3C.2a.3; characteristics and outcomes of patients infected with different clades were similar. No resistance to antiviral medications was found.

Legionnaires' disease caused by Legionella longbeachae in Taiwan, 2006-2010.

The aim of the present study was to investigate the epidemiology of Legionnaires' disease (LD) caused by Legionella longbeachae in Taiwan during 2006-2010. A total of six cases were identified prospectively, accounting for 1.6% of all laboratory-confirmed LD cases and 4.4% of culture-positive LD cases. All six cases occurred between April and August. The male to female ratio was 0.5. These six LD patients had a higher median age than those with LD due to Legionella pneumophila. Four of the six patients presented with pleural effusion and five survived the infection episode. Only two patients had a potential soil contact history prior to LD onset. The patients resided in divergent geographical areas without a common exposure history. The individual genomic DNA banding patterns of the six L. longbeachae isolates analyzed by pulsed-field gel electrophoresis (PFGE) were unique, supporting the hypothesis that the L. longbeachae infections occurred sporadically.

Community outbreak of adenovirus, Taiwan, 2011.

In 2011, a large community outbreak of human adenovirus (HAdV) in Taiwan was detected by a nationwide surveillance system. The epidemic lasted from week 11 through week 41 of 2011 (March 14-October 16, 2011). Although HAdV-3 was the predominant strain detected (74%), an abrupt increase in the percentage of infections caused by HAdV-7 occurred, from 0.3% in 2008-2010 to 10% in 2011. Clinical information was collected for 202 inpatients infected with HAdV; 31 (15.2%) had severe infection that required intensive care, and 7 of those patients died. HAdV-7 accounted for 10%, 12%, and 41% of infections among outpatients, inpatients with nonsevere infection, and inpatients with severe infection, respectively (p<0.01). The HAdV-7 strain detected in this outbreak is identical to a strain recently reported in the People's Republic of China (HAdV7-HZ/SHX/CHN/2009). Absence of circulating HAdV-7 in previous years and introduction of an emerging strain are 2 factors that caused this outbreak.

Molecular detection and incidence of human papillomavirus in neonates: methodology and a pilot study in a medical center.

BACKGROUND/PURPOSE: Human papillomavirus (HPV) infection can cause laryngeal papillomas in children. Vertical transmission has been confirmed. This study aimed to establish a sensitive molecular diagnostic method and understand the incidence of the HPV-6 and HPV-11 in neonates with intubation. METHODS: We enrolled 108 newborns between October 2007 and January 2010. All neonates were intubated due to underlying disease. The specimens were collected via endotracheal aspiration. DNA of HPV types 6 and 11 was detected by real-time PCR and nested PCR. RESULTS: HPV-DNA was detected in eight of the 108 newborns studied. Seven respiratory specimens tested positive for HPV-11 and one was positive for HPV-6. The HPV 6/11 detection rate in neonates was 7.4% (8/108). CONCLUSION: A rapid, sensitive, specific, and reproducible RT-PCR method and nest PCR were developed for the detection and differentiation of HPV-6 and HPV-11 genomic variants in a single PCR reaction. The assays are of great value for clinical and epidemiologic studies of HPV-6 and HPV-11 infections. Neonatal HPV colonization may be related to juvenile-onset recurrent respiratory papillomatosis. The transmission route may be from mother to child. The clinical significance of neonatal carriage of HPV-6 or HPV-11 warrants further study.

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.

An outbreak of coxsackievirus A6 hand, foot, and mouth disease associated with onychomadesis in Taiwan, 2010.

BACKGROUND: In 2010, an outbreak of coxsackievirus A6 (CA6) hand, foot and mouth disease (HFMD) occurred in Taiwan and some patients presented with onychomadesis and desquamation following HFMD. Therefore, we performed an epidemiological and molecular investigation to elucidate the characteristics of this outbreak. METHODS: Patients who had HFMD with positive enterovirus isolation results were enrolled. We performed a telephone interview with enrolled patients or their caregivers to collect information concerning symptoms, treatments, the presence of desquamation, and the presence of nail abnormalities. The serotypes of the enterovirus isolates were determined using indirect immunofluorescence assays. The VP1 gene was sequenced and the phylogenetic tree for the current CA6 strains in 2010, 52 previous CA6 strains isolated in Taiwan from 1998 through 2009, along with 8 reference sequences from other countries was constructed using the neighbor-joining command in MEGA software. RESULTS: Of the 130 patients with laboratory-confirmed CA6 infection, some patients with CA6 infection also had eruptions around the perioral area (28, 22%), the trunk and/or the neck (39, 30%) and generalized skin eruptions (6, 5%) in addition to the typical presentation of skin eruptions on the hands, feet, and mouths. Sixty-six (51%) CA6 patients experienced desquamation of palms and soles after the infection episode and 48 (37%) CA6 patients developed onychomadesis, which only occurred in 7 (5%) of 145 cases with non-CA6 enterovirus infection (p < 0.001). The sequences of viral protein 1 of CA6 in 2010 differ from those found in Taiwan before 2010, but are similar to those found in patients in Finland in 2008. CONCLUSIONS: HFMD patients with CA6 infection experienced symptoms targeting a broader spectrum of skin sites and more profound tissue destruction, i.e., desquamation and nail abnormalities.

Change in hepatitis A epidemiology after vaccinating high risk children in Taiwan, 1995-2008.

Taiwan started to immunize children in 30 indigenous townships against hepatitis A since June 1995. The program was further expanded to 19 non-indigenous townships with higher incidence or increased risk of epidemic in 1997-2002, covering 2% of total population. Annual incidence of hepatitis A decreased from 2.96 in 1995 (baseline period) to 0.90/100,000 in 2003-2008 (vaccination period). The incidence in vaccinated townships and unvaccinated townships declined 98.3% (49.66-0.86/100,000) and 52.6% (1.90-0.90/100,000). In 2003-2008, incidence doubled in people aged >=30 years, mostly in unvaccinated townships (0.42-0.92). During 2003-2008, travel to endemic countries was the most commonly reported risk factor (13.5%). First dose vaccine coverage was 78.8% in 1994-2005 birth cohort. Taiwan's experience demonstrates the great, long-term efficacy of hepatitis A vaccine in disease control in vaccinated townships, and out-of-cohort effect in unvaccinated townships. Further reduction can be achieved by improving vaccination coverage of adults at risk.

Outbreak of influenza in an overseas student travel group--Taiwan 2008.

Influenza is a frequent cause of acute respiratory illness (ARI). In July 2008, we conducted a retrospective cohort study to investigate an influenza outbreak occurring in an overland travel group of overseas students. ARI was defined as the presence of any respiratory symptom such as cough, rhinorrhoea, sore throat or stuffy nose. Influenza-like illness (ILI) was defined as ARI plus fever > or =38 degrees C. Throat swabs were taken from symptomatic participants and a real-time polymerase chain reaction (RT-PCR) was performed. One hundred and seventy participants were interviewed. Forty-four (26%) had an ARI and 22 (13%) had an ILI. Of the 33 specimens collected, 18 (54%) were positive for influenza A/H3N2. Taiwanese group leaders had increased risk of acquiring both ARI and ILI (ARI relative risk (RR) 2.2, 95% confidence interval (CI) 1.3-3.7 and ILI RR 2.8, 95% CI 1.2-6.3). Fifteen participants were vaccinated. The vaccine effectiveness was 52% for ILI (p = 0.70). The outbreak stopped after cohorting and the use of surgical masks. Vaccination appeared to be effective in preventing infection.

Microbiology and epidemiology of brain abscess and subdural empyema in a medical center: a 10-year experience.

BACKGROUND AND PURPOSE: Brain abscess and subdural empyema are the 2 most common forms of intracranial pyogenic infections. Predisposing factors and etiological agents may change with time. This study examined the epidemiological features of these conditions. METHODS: The medical records of all inpatients with a diagnosis of brain abscess or subdural empyema from 1998 to 2007 were reviewed. The diagnosis was confirmed by imaging study or operative findings. RESULTS: 151 episodes of brain abscess were diagnosed in 150 patients, and 10 patients had subdural empyema. The incidence of brain abscess fluctuated over time, while that of subdural empyema remained stable. The mean +/- standard deviation age of patients with brain abscess was significantly greater than that of patients with subdural empyema (48.5 +/- 19 years vs 25.4 +/- 24 years; p = 0.004). The number of patients with hematogenous brain abscess increased from 7 in 1998 to 2002 to 19 in 2003 to 2007, while that of those with infection related to operation decreased from 10 to 5. Most subdural empyema was related to bacterial meningitis (4 of 10). Etiological agents were identified in 53% of brain abscesses, including Enterobacteriaceae spp. (21.3%), Streptococcus spp. (20%), and mixed pathogens (17.5%). Klebsiella pneumoniae was the most common enteric bacteria isolated (15.3%), especially in patients with diabetes mellitus, but was not observed in children younger than 18 years. CONCLUSIONS: In contrast to western countries, K. pneumoniae plays an important role in intracranial pyogenic infections in Taiwan. The pathogens and routes of infection are different between children and adults.