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Background: This study investigated viral load in surgical masks worn by adult patients infected with respiratory viruses. Method: Surgical masks were dissected into eight pieces at pre-selected sites: inner, middle, and outer layers at the nose (N1-N3) and mouth (M1-M3), as well as full-thickness on the right (RS) and left (LS) sides. Viral load was detected, correlated with nasopharyngeal specimens and patients' demographics. Result: Among 230 patients infected with influenza A virus (n=91), respiratory syncytial virus (RSV) (n=61), and SARS-CoV-2 (n=78) from April 1 to August 31, 2023, 90.9% (209/230) were from the medical specialty. Of the 230 surgical masks collected, viral RNA was detected in 79.6% at one or more sites, with 75.7% positive at N1 or M1, 55.2% positive at N3 or M3, and 22.6% exhibiting viral RNA at all sites. Pearson correlation showed viral load correlation between nasopharyngeal specimens and N1 (0.244, p=0.002) and M1 (0.174, p=0.031). The mean viral load at N1 (4.14 ± 1.46 log10 copies/ml) was significantly higher than M1 (3.74 ± 1.32 log10 copies/ml, p=0.014) and N3 (3.58 ± 1.27 log10 copies/ml, p=0.003). Significant differences in viral load were observed across N1-N3 and M1-M3 in RSV patients, but not in influenza A or SARS-CoV-2 patients. SARS-CoV-2 patients exhibited significantly lower viral load at RS and LS sites compared to influenza A or RSV patients. Conclusion: Viral RNA was detected in N3 or M3 sites in our masks, highlighting the potential risk associated in these areas. Differential viral load across various sites in surgical masks worn by patients infected with different respiratory viruses warrants further investigation.
In Hong Kong, the percentage of older drug users has increased over the last two decades. However, the motivations behind their drug-use behaviours have received little research attention. This study focuses on older drug users who are enrolled in methadone treatment programmes but still use illicit drugs (mixed use). Some studies in the criminological literature and government discourse consider drug users to be passive and lacking self-control. However, in-depth interviews in with 25 older mixed users (aged over 50 years) in Hong Kong revealed that mixed use is one of the various strategies they actively employ to improve their self-perceived quality of life. Using the framework of the selective optimization with compensation model, this study (1) describes the strategies older mixed users adopt as active agents to improve their self-perceived quality of life while coexisting with their addiction; and (2) explains how these strategies were affected and constrained by Hong Kong’s prohibitionist drug policy. I infer that prohibitionist drug policies that emphasize on total drug abstinence may fail to cater to the needs of older drug users who have undergone several relapses and treatments in their lifetimes and do not think they can give up using drugs. This study also provides evidence to show how some drug users may act as active agents to manage and coexist with their addiction, and their agency seems to be constrained by the wider drug policy implemented in Hong Kong.
Hong Kong experienced four epidemic waves caused by the ancestral strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2020–2021 and a large Omicron wave in 2022. Few studies have assessed antibacterial prescribing for coronavirus disease 2019 (COVID-19) inpatients throughout the pandemic.
Objectives:
To describe inpatient antibacterial prescribing and explore factors associated with their prescription.
Methods:
Electronic health records of patients with COVID-19 admitted to public hospitals in Hong Kong from 21 January 2020 to 30 September 2022 were used to assess the prevalence and rates of inpatient antibacterial drug use (days of therapy/1,000 patient days [DOT/1,000 PD]). We used multivariable logistic regression to investigate potential associations between patients’ baseline characteristics and disease severity and prescription of an antibacterial drug during hospital admission.
Results:
Among 65,810 inpatients with COVID-19, 54.0% were prescribed antibacterial drugs (550.5 DOT/1,000 PD). Compared to waves 1–2 (46.7%; 246.9 DOT/1,000 PD), the prescriptions were lowest during wave 4 (28.0%; 246.9; odds ratio (OR): 0.39, 95% CI: 0.31–0.49) and peaked in early wave 5 (64.6%; 661.2; 0.82, 0.65–1.03). Older age (≥80 years: OR 2.66, 95% CI, 2.49–2.85; 60–79 years: 1.59, 1.51–1.69, compared with 20–59 years), more severe disease (fatal: 3.64, 3.2–4.16; critical: 2.56, 2.14–3.06, compared with severe), and COVID-19 vaccine doses (two doses: 0.74, 0.69–0.78; three doses: 0.69, 0.64–0.74; four doses: 0.52, 0.44–0.62, compared with unvaccinated) were associated with inpatient antibacterial drug use.
Conclusions:
Antibacterial prescribing changed over time for hospitalized patients with confirmed COVID-19 and was potentially related to patients’ demographics, medical conditions, and COVID-19 vaccination status as well as healthcare capacity during epidemic waves.
We aimed to investigate child mortality, perinatal morbidities and congenital anomalies born by women with substance misuse during or before pregnancy (DP or BP).
Methods
Taiwan Birth Registration from 2004 to 2014 linking Integrated Illicit Drug Databases used to include substance misuse participates. Children born by mothers convicted of substance misuse DP or BP were the substance-exposed cohort. Two substance-unexposed comparison cohorts were established: one comparison cohort selected newborns from the rest of the population on a ratio of 1:1 and exact matched by the child’s gender, child’s birth year, mother’s birth year and child’s first use of the health insurance card; another comparison cohort matched newborns from exposed and unexposed mothers by their propensity scores calculated from logistic regression.
Results
The exposure group included 1776 DP, 1776 BP and 3552 unexposed individuals in exact-matched cohorts. A fourfold increased risk of deaths in children born by mothers exposed to substance during pregnancy was found compared to unexposed group (hazard ratio [HR] = 4.54, 95% confidence interval (CI): 2.07–9.97]. Further multivariate Cox regression models with adjustments and propensity matching substantially attenuated HRs on mortality in the substance-exposed cohort (aHR = 1.62, 95% CI: 1.10–2.39). Raised risks of perinatal morbidities and congenital anomalies were also found.
Conclusions
Increased risks of child mortality, perinatal morbidities or congenital anomalies were found in women with substance use during pregnancy. From estimates before and after adjustments, our results showed that having outpatient visits or medical utilizations during pregnancy were associated with substantially attenuated HRs on mortality in the substance-exposed cohort. Therefore, the excess mortality risk might be partially explained by the lack of relevant antenatal clinical care. Our finding may suggest that the importance of early identification, specific abstinence program and access to appropriate antenatal care might be helpful in reducing newborn mortality. Adequate prevention policies may be formulated.
To evaluate antibiotic prescribing behavior (APB) among physicians with various specialties in five Asian countries.
Design:
Survey of antibiotics prescribing behavior in three stages (initial, on-treatment, and de-escalation stages).
Methods:
Participants included internists, infectious diseases (ID) specialists, hematologists, intensivists, and surgeons. Participants’ characteristics, patterns of APB, and perceptions of antimicrobial stewardship were collected. A multivariate analysis was conducted to evaluate factors associated with appropriate APB.
Results:
There were 367 participants. The survey response rate was 82.5% (367/445). For the initial stage, different specialties had different choices for empiric treatment. For the on-treatment stage, if the patient does not respond to empiric treatment, most respondents will step up to broader-spectrum antibiotics (273/367: 74.39%). For the de-escalation stage, the rate of de-escalation was 10%–60% depending on the specialty. Most respondents would de-escalate antibiotics based on guidelines (250/367: 68.12%). De-escalation was mostly reported by ID specialists (66/106: 62.26%). Respondents who reported that they performed laboratory investigations prior to empirical antibiotic prescriptions (aOR = 2.83) were associated with appropriate use, while respondents who reported ID consultation were associated with appropriate antibiotic management for infections not responding to empiric treatment (aOR = 40.87); adherence with national guidelines (aOR = 2.57) was associated with reported successful carbapenem de-escalation.
Conclusion:
This study highlights the variation in practices and gaps in appropriate APB on three stages of antibiotic prescription among different specialties. Education on appropriate investigation, partnership with ID specialist, and availability and adherence with national guidelines are critical to help guide appropriate APB among different specialties.
To evaluate the impact of a diagnostic stewardship intervention on Clostridioides difficile healthcare-associated infections (HAI).
Design:
Quality improvement study.
Setting:
Two urban acute care hospitals.
Interventions:
All inpatient stool testing for C. difficile required review and approval prior to specimen processing in the laboratory. An infection preventionist reviewed all orders daily through chart review and conversations with nursing; orders meeting clinical criteria for testing were approved, orders not meeting clinical criteria were discussed with the ordering provider. The proportion of completed tests meeting clinical criteria for testing and the primary outcome of C. difficile HAI were compared before and after the intervention.
Results:
The frequency of completed C. difficile orders not meeting criteria was lower [146 (7.5%) of 1,958] in the intervention period (January 10, 2022–October 14, 2022) than in the sampled 3-month preintervention period [26 (21.0%) of 124; P < .001]. C. difficile HAI rates were 8.80 per 10,000 patient days prior to the intervention (March 1, 2021–January 9, 2022) and 7.69 per 10,000 patient days during the intervention period (incidence rate ratio, 0.87; 95% confidence interval, 0.73–1.05; P = .13).
Conclusions:
A stringent order-approval process reduced clinically nonindicated testing for C. difficile but did not significantly decrease HAIs.
We obtained 24 air samples in 8 general wards temporarily converted into negative-pressure wards admitting coronavirus disease 2019 (COVID-19) patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant BA.2.2 in Hong Kong. SARS-CoV-2 RNA was detected in 19 (79.2%) of 24 samples despite enhanced indoor air dilution. It is difficult to prevent airborne transmission of SARS-CoV-2 in hospitals.
Air dispersal of respiratory viruses other than SARS-CoV-2 has not been systematically reported. The incidence and factors associated with air dispersal of respiratory viruses are largely unknown.
Methods:
We performed air sampling by collecting 72,000 L of air over 6 hours for pediatric and adolescent patients infected with parainfluenza virus 3 (PIF3), respiratory syncytial virus (RSV), rhinovirus, and adenovirus. The patients were singly or 2-patient cohort isolated in airborne infection isolation rooms (AIIRs) from December 3, 2021, to January 26, 2022. The viral load in nasopharyngeal aspirates (NPA) and air samples were measured. Factors associated with air dispersal were investigated and analyzed.
Results:
Of 20 singly isolated patients with median age of 30 months (range, 3 months–15 years), 7 (35%) had air dispersal of the viruses compatible with their NPA results. These included 4 (40%) of 10 PIF3-infected patients, 2 (66%) of 3 RSV-infected patients, and 1 (50%) of 2 adenovirus-infected patients. The mean viral load in their room air sample was 1.58×103 copies/mL. Compared with 13 patients (65%) without air dispersal, these 7 patients had a significantly higher mean viral load in their NPA specimens (6.15×107 copies/mL vs 1.61×105 copies/mL; P < .001). Another 14 patients were placed in cohorts as 7 pairs infected with the same virus (PIF3, 2 pairs; RSV, 3 pairs; rhinovirus, 1 pair; and adenovirus, 1 pair) in double-bed AIIRs, all of which had air dispersal. The mean room air viral load in 2-patient cohorts was significantly higher than in rooms of singly isolated patients (1.02×104 copies/mL vs 1.58×103 copies/mL; P = .020).
Conclusion:
Air dispersal of common respiratory viruses may have infection prevention and public health implications.
Nosocomial outbreaks leading to healthcare worker (HCW) infection and death have been increasingly reported during the coronavirus disease 2019 (COVID-19) pandemic.
Objective:
We implemented a strategy to reduce nosocomial acquisition.
Methods:
We summarized our experience in implementing a multipronged infection control strategy in the first 300 days (December 31, 2019, to October 25, 2020) of the COVID-19 pandemic under the governance of Hospital Authority in Hong Kong.
Results:
Of 5,296 COVID-19 patients, 4,808 (90.8%) were diagnosed in the first pandemic wave (142 cases), second wave (896 cases), and third wave (3,770 cases) in Hong Kong. With the exception of 1 patient who died before admission, all COVID-19 patients were admitted to the public healthcare system for a total of 78,834 COVID-19 patient days. The median length of stay was 13 days (range, 1–128). Of 81,955 HCWs, 38 HCWs (0.05%; 2 doctors and 11 nurses and 25 nonprofessional staff) acquired COVID-19. With the exception of 5 of 38 HCWs (13.2%) infected by HCW-to-HCW transmission in the nonclinical settings, no HCW had documented transmission from COVID-19 patients in the hospitals. The incidence of COVID-19 among HCWs was significantly lower than that of our general population (0.46 per 1,000 HCWs vs 0.71 per 1,000 population; P = .008). The incidence of COVID-19 among professional staff was significantly lower than that of nonprofessional staff (0.30 vs 0.66 per 1,000 full-time equivalent; P = .022).
Conclusions:
A hospital-based approach spared our healthcare service from being overloaded. With our multipronged infection control strategy, no nosocomial COVID-19 in was identified among HCWs in the first 300 days of the COVID-19 pandemic in Hong Kong.
This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to coronavirus disease 2019 (COVID-19) with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplementary materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
Extensive environmental contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been reported in hospitals during the coronavirus disease 2019 (COVID-19) pandemic. We report our experience with the practice of directly observed environmental disinfection (DOED) in a community isolation facility (CIF) and a community treatment facility (CTF) in Hong Kong.
Methods:
The CIF, with 250 single-room bungalows in a holiday camp, opened on July 24, 2020, to receive step-down patients from hospitals. The CTF, with 500 beds in open cubicles inside a convention hall, was activated on August 1, 2020, to admit newly diagnosed COVID-19 patients from the community. Healthcare workers (HCWs) and cleaning staff received infection control training to reinforce donning and doffing of personal protective equipment and to understand the practice of DOED, in which the cleaning staff observed patient and staff activities and then performed environmental disinfection immediately thereafter. Supervisors also observed cleaning staff to ensure the quality of work. In the CTF, air and environmental samples were collected on days 7, 14, 21, and 28 for SARS-CoV-2 detection by RT-PCR. Patient compliance with mask wearing was also recorded.
Results:
Of 291 HCWs and 54 cleaning staff who managed 243 patients in the CIF and 674 patients in the CTF from July 24 to August 29, 2020, no one acquired COVID-19. All 24 air samples and 520 environmental samples collected in the patient area of the CTF were negative for SARS-CoV-2. Patient compliance with mask wearing was 100%.
Conclusion:
With appropriate infection control measures, zero environmental contamination and nosocomial transmission of SARS-CoV-2 to HCWs and cleaning staff was achieved.
Background: Contaminated chlorhexidine produced by a single company has been implicated in the outbreak or pseudo-outbreak of Burkholderia cepacia complex (BCC). However, simultaneous occurrence of multiple brands of contaminated chlorhexidine supplied by different manufacturers resulting in a persistent outbreak for >1 year has not been well described. Objective: We report an outbreak of BCC with epidemiological investigation and using whole-genome sequencing (WGS) analysis of patient and environmental isolates in Hong Kong. Methods: Upon the investigation of a cohort of renal patients undergoing peritoneal dialysis colonized or infected with BCC in their exit sites, different brands of 0.05% aqueous chlorhexidine (aqCHX) used for exit site dressing, supplied from hospital or purchased from community pharmacies by patients, were cultured. A risk factor analysis for exit-site acquisition of BCC was performed. A site visit to a local manufacturer was conducted to investigate the process of production and to collect environmental samples for culture, which were further analyzed by WGS along with the BCC isolates cultured from patients and aqCHX purchased from community pharmacies. Results: Four patients undergoing peritoneal dialysis had cultures positive for BCC in the exit site swab in September 2019. A snapshot screening revealed 88 (32.0%) of 275 renal dialysis patients colonized with BCC. Of these patients, 47 (17.1%) were newly diagnosed and 41 (14.9%) were known to be colonized or infected with BCC according to retrospective data retrieval from January 1, 2018. A significantly greater proportion of patients with newly diagnosed BCC (cases) had used contaminated aqCHX for exit-site dressing than those with culture negative for BCC (controls): 38 of 47 (80.9%) versus 54 of 187 (28.9%) (P < .001). Of 161 aqCHX samples, 10 brands from 4 manufacturers (purchased from community pharmacies), 125 (77.6%) were culture positive for BCC, whereas all 77 aqCHX samples supplied by the hospital, which are different brands and are produced by different manufacturers, were proven to be sterile. Of the 28 environmental samples taken from a local manufacturer during the site visit, 19 samples (67.9%, 3 collected from the instrument for production of aqCHX and all 16 newly produced aqCHX samples) were culture positive for BCC. WGS revealed 3 major clusters characterized by B. cenocepacia genomovar IIIA ST1547 and 2 novel MLST clusters from 52 patients and 26 environmental isolates selected. Conclusions: This outbreak was terminated by product recall, and the government has decided to take regulatory actions to ensure the sterility of antiseptics, including aqCHX.
Universal masking for healthcare workers and patients in hospitals was adopted to combat coronavirus disease 2019 (COVID-19), with compliance rates of 100% and 75.9%, respectively. Zero rates of nosocomial influenza A, influenza B, and respiratory syncytial virus infection were achieved from February to April 2020, which was significantly lower than the corresponding months in 2017–2019.
To understand hospital policies and practices as the COVID-19 pandemic accelerated, the Society for Healthcare Epidemiology of America (SHEA) conducted a survey through the SHEA Research Network (SRN). The survey assessed policies and practices around the optimization of personal protection equipment (PPE), testing, healthcare personnel policies, visitors of COVID-19 patients in relation to procedures, and types of patients. Overall, 69 individual healthcare facilities responded in the United States and internationally, for a 73% response rate.
The role of severe respiratory coronavirus virus 2 (SARS-CoV-2)–laden aerosols in the transmission of coronavirus disease 2019 (COVID-19) remains uncertain. Discordant findings of SARS-CoV-2 RNA in air samples were noted in early reports.
Methods:
Sampling of air close to 6 asymptomatic and symptomatic COVID-19 patients with and without surgical masks was performed with sampling devices using sterile gelatin filters. Frequently touched environmental surfaces near 21 patients were swabbed before daily environmental disinfection. The correlation between the viral loads of patients’ clinical samples and environmental samples was analyzed.
Results:
All air samples were negative for SARS-CoV-2 RNA in the 6 patients singly isolated inside airborne infection isolation rooms (AIIRs) with 12 air changes per hour. Of 377 environmental samples near 21 patients, 19 (5.0%) were positive by reverse-transcription polymerase chain reaction (RT-PCR) assay, with a median viral load of 9.2 × 102 copies/mL (range, 1.1 × 102 to 9.4 × 104 copies/mL). The contamination rate was highest on patients’ mobile phones (6 of 77, 7.8%), followed by bed rails (4 of 74, 5.4%) and toilet door handles (4 of 76, 5.3%). We detected a significant correlation between viral load ranges in clinical samples and positivity rate of environmental samples (P < .001).
Conclusion:
SARS-CoV-2 RNA was not detectable by air samplers, which suggests that the airborne route is not the predominant mode of transmission of SARS-CoV-2. Wearing a surgical mask, appropriate hand hygiene, and thorough environmental disinfection are sufficient infection control measures for COVID-19 patients isolated singly in AIIRs. However, this conclusion may not apply during aerosol-generating procedures or in cohort wards with large numbers of COVID-19 patients.
To describe the infection control preparedness measures undertaken for coronavirus disease (COVID-19) due to SARS-CoV-2 (previously known as 2019 novel coronavirus) in the first 42 days after announcement of a cluster of pneumonia in China, on December 31, 2019 (day 1) in Hong Kong.
Methods:
A bundled approach of active and enhanced laboratory surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and contact tracing for healthcare workers (HCWs) with unprotected exposure in the hospitals was implemented. Epidemiological characteristics of confirmed cases, environmental samples, and air samples were collected and analyzed.
Results:
From day 1 to day 42, 42 of 1,275 patients (3.3%) fulfilling active (n = 29) and enhanced laboratory surveillance (n = 13) were confirmed to have the SARS-CoV-2 infection. The number of locally acquired case significantly increased from 1 of 13 confirmed cases (7.7%, day 22 to day 32) to 27 of 29 confirmed cases (93.1%, day 33 to day 42; P < .001). Among them, 28 patients (66.6%) came from 8 family clusters. Of 413 HCWs caring for these confirmed cases, 11 (2.7%) had unprotected exposure requiring quarantine for 14 days. None of these was infected, and nosocomial transmission of SARS-CoV-2 was not observed. Environmental surveillance was performed in the room of a patient with viral load of 3.3 × 106 copies/mL (pooled nasopharyngeal and throat swabs) and 5.9 × 106 copies/mL (saliva), respectively. SARS-CoV-2 was identified in 1 of 13 environmental samples (7.7%) but not in 8 air samples collected at a distance of 10 cm from the patient’s chin with or without wearing a surgical mask.
Conclusion:
Appropriate hospital infection control measures was able to prevent nosocomial transmission of SARS-CoV-2.
Prehospital vital signs are used to triage trauma patients to mobilize appropriate resources and personnel prior to patient arrival in the emergency department (ED). Due to inherent challenges in obtaining prehospital vital signs, concerns exist regarding their accuracy and ability to predict first ED vitals.
Hypothesis/Problem:
The objective of this study was to determine the correlation between prehospital and initial ED vitals among patients meeting criteria for highest levels of trauma team activation (TTA). The hypothesis was that in a medical system with short transport times, prehospital and first ED vital signs would correlate well.
Methods:
Patients meeting criteria for highest levels of TTA at a Level I trauma center (2008-2018) were included. Those with absent or missing prehospital vital signs were excluded. Demographics, injury data, and prehospital and first ED vital signs were abstracted. Prehospital and initial ED vital signs were compared using Bland-Altman intraclass correlation coefficients (ICC) with good agreement as >0.60; fair as 0.40-0.60; and poor as <0.40).
Results:
After exclusions, 15,320 patients were included. Mean age was 39 years (range 0-105) and 11,622 patients (76%) were male. Mechanism of injury was blunt in 79% (n = 12,041) and mortality was three percent (n = 513). Mean transport time was 21 minutes (range 0-1,439). Prehospital and first ED vital signs demonstrated good agreement for Glasgow Coma Scale (GCS) score (ICC 0.79; 95% CI, 0.77-0.79); fair agreement for heart rate (HR; ICC 0.59; 95% CI, 0.56-0.61) and systolic blood pressure (SBP; ICC 0.48; 95% CI, 0.46-0.49); and poor agreement for pulse pressure (PP; ICC 0.32; 95% CI, 0.30-0.33) and respiratory rate (RR; ICC 0.13; 95% CI, 0.11-0.15).
Conclusion:
Despite challenges in prehospital assessments, field GCS, SBP, and HR correlate well with first ED vital signs. The data show that these prehospital measurements accurately predict initial ED vitals in an urban setting with short transport times. The generalizability of these data to settings with longer transport times is unknown.