Repeat virological and serological profiles in hospitalized patients initially tested by nasopharyngeal RT-PCR for SARS-CoV-2.

Real-time polymerase chain reaction (PCR) for SARS-CoV-2 is the mainstay of COVID-19 diagnosis, yet there are conflicting reports on its diagnostic performance. Wide ranges of false-negative PCR tests have been reported depending on clinical presentation, the timing of testing, specimens tested, testing method, and reference standard used. We aimed to estimate the frequency of discordance between initial nasopharyngeal (NP) PCR and repeat NP sampling PCR and serology in acutely ill patients admitted to the hospital. Panel diagnosis of COVID-19 infection is further utilized in discordance analysis. Included in the study were 160 patients initially tested by NP PCR with repeat NP sampling PCR and/or serology performed. The percent agreement between initial and repeat PCR was 96.7%, while the percent agreement between initial PCR and serology was 98.9%. There were 5 (3.1%) cases with discordance on repeat testing. After discordance analysis, 2 (1.4%) true cases tested negative on initial PCR. Using available diagnostic methods, discordance on repeat NP sampling PCR and/or serology is a rare occurrence.

HIV serology signal-to-cutoff ratio as a rapid method to predict confirmation of HIV infection.

Early and rapid detection of patients with HIV is a key to preventing further transmission. The purpose of this study was to assess the ability of signal-to-cutoff (S/CO) ratio from initial screening fourth-generation HIV serology to predict subsequent confirmation of HIV. Patients with a first-time positive HIV serology (S/CO ratio ≥ 1) from 2012 to 2016 were included. Ratios were compared to the results of confirmatory testing. Predictive probabilities (PPs) of a positive confirmatory result were calculated based on a logistic regression model. A total of 45,138 HIV serology tests were performed; 250 patients met inclusion criteria, comprising 84 (34%) HIV negative patients, 136 (54%) chronic infections, and 30 (12%) acute infections. The PP of a confirmed positive result increased with higher S/CO ratios, with a PP of 100% for a S/CO of 55 (95% CI 95-100). This study enables a more informed discussion of the probability of HIV infection, based on HIV serology S/CO thresholds, prior to a confirmatory result.

Implementing a province-wide mandatory vaccinate-or-mask policy at healthcare facilities in British Columbia, Canada.

OBJECTIVES: In 2012, British Columbia (BC) became the first Canadian province to implement an influenza prevention policy requiring healthcare workers (HCW) to either be vaccinated annually against influenza or wear a mask in patient care areas during the influenza season. This study describes an evaluation of influenza policy implementation processes and identifies supports and challenges related to successful policy implementation at the level of healthcare facilities, during the second policy year (2013/14). METHODS: Implementation leaders from 262 long-term care (LTC) and acute care facilities, mostly in three of BC's five regional Health Authorities, were invited to participate in an online survey following the 2013/14 influenza season. Descriptive quantitative and qualitative analyses identified common and effective strategies for improving vaccination coverage and policy compliance. RESULTS: A total of 127 respondents completed the survey on behalf of 33 acute care and 99 LTC facilities, representing 36% of acute care and 27% of LTC facilities in BC. Respondents agreed that the policy was successfully implemented at 89% of facilities, and implementation was reported to be easy at 52% of facilities. The findings elaborate on communication and leadership strategies, campaign logistics and enforcement approaches involved in policy implementation. CONCLUSION: Implementation of a vaccinate-or-mask influenza policy is complex. This study provides insight for other jurisdictions considering implementing such a policy and offers practical recommendations for facilities and health authorities.

Antimicrobial stewardship for hospitalized patients with viral respiratory tract infections.

BACKGROUND: The purpose of this study was to implement a targeted antimicrobial stewardship intervention for patients with a viral respiratory tract infection. METHODS: This was a quasi-experimental before and after audit and feedback intervention of adult inpatients with a positive polymerase chain reaction for a respiratory virus in 2 acute care hospitals in Vancouver, Canada. Audit and feedback was implemented based on 2 criteria: microbiology (no positive bacterial cultures) and chest imaging (absence of pneumonia or consolidation on radiology dictation). A chart review was conducted to assess for days of antibiotics postviral diagnosis. Outcomes including length of stay, intensive care unit admission within 14 days, mechanical ventilation within 14 days, antibiotics prescribed within 14 days, Clostridium difficile infection diagnosed within 30 days, and readmission within 30 days were also reviewed in comparison with the previous year. RESULTS: Antimicrobial stewardship recommendations for hospitalized patients with viral respiratory tract infections were accepted for 77% of cases. This targeted approach based on easily assessed parameters translated into a 1.3-day (95% confidence interval, 0.3-2.3; P < .01) decrease in mean days of antibiotics postviral diagnosis compared with the previous year without systematic interventions. Compared with the previous year, no differences were identified for adverse outcomes associated with the intervention. CONCLUSIONS: A targeted antimicrobial stewardship intervention integrating virology testing with the treating physician facilitated a reduction in duration of antibiotic treatment for viral respiratory tract infections.

Reduction in hospital-associated methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus with daily chlorhexidine gluconate bathing for medical inpatients.

BACKGROUND: Daily bathing with chlorhexidine gluconate (CHG) is increasingly used in intensive care units to prevent hospital-associated infections, but limited evidence exists for noncritical care settings. METHODS: A prospective crossover study was conducted on 4 medical inpatient units in an urban, academic Canadian hospital from May 1, 2014-August 10, 2015. Intervention units used CHG over a 7-month period, including a 1-month wash-in phase, while control units used nonmedicated soap and water bathing. Rates of hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) colonization or infection were the primary end point. Hospital-associated S. aureus were investigated for CHG resistance with a qacA/B and smr polymerase chain reaction (PCR) and agar dilution. RESULTS: Compliance with daily CHG bathing was 58%. Hospital-associated MRSA and VRE was decreased by 55% (5.1 vs 11.4 cases per 10,000 inpatient days, P = .04) and 36% (23.2 vs 36.0 cases per 10,000 inpatient days, P = .03), respectively, compared with control cohorts. There was no significant difference in rates of hospital-associated Clostridium difficile. Chlorhexidine resistance testing identified 1 isolate with an elevated minimum inhibitory concentration (8 µg/mL), but it was PCR negative. CONCLUSIONS: This prospective pragmatic study to assess daily bathing for CHG on inpatient medical units was effective in reducing hospital-associated MRSA and VRE. A critical component of CHG bathing on medical units is sustained and appropriate application, which can be a challenge to accurately assess and needs to be considered before systematic implementation.

Whole-Genome Sequencing of Measles Virus Genotypes H1 and D8 During Outbreaks of Infection Following the 2010 Olympic Winter Games Reveals Viral Transmission Routes.

We used whole-genome sequencing to investigate a dual-genotype outbreak of measles occurring after the XXI Olympic Winter Games in Vancouver, Canada. By sequencing 27 complete genomes from H1 and D8 genotype measles viruses isolated from outbreak cases, we estimated the virus mutation rate, determined that person-to-person transmission is typically associated with 0 mutations between isolates, and established that a single introduction of H1 virus led to the expansion of the outbreak beyond Vancouver. This is the largest measles genomics project to date, revealing novel aspects of measles virus genetics and providing new insights into transmission of this reemerging viral pathogen.

Cost effectiveness of alternative planned places of birth in woman at low risk of complications: evidence from the Birthplace in England national prospective cohort study.

OBJECTIVES: To estimate the cost effectiveness of alternative planned places of birth. DESIGN: Economic evaluation with individual level data from the Birthplace national prospective cohort study. SETTING: 142 of 147 trusts providing home birth services, 53 of 56 freestanding midwifery units, 43 of 51 alongside midwifery units, and a random sample of 36 of 180 obstetric units, stratified by unit size and geographical region, in England, over varying periods of time within the study period 1 April 2008 to 30 April 2010. PARTICIPANTS: 64,538 women at low risk of complications before the onset of labour. INTERVENTIONS: Planned birth in four alternative settings: at home, in freestanding midwifery units, in alongside midwifery units, and in obstetric units. MAIN OUTCOME MEASURES: Incremental cost per adverse perinatal outcome avoided, adverse maternal morbidity avoided, and additional normal birth. The non-parametric bootstrap method was used to generate net monetary benefits and construct cost effectiveness acceptability curves at alternative thresholds for cost effectiveness. RESULTS: The total unadjusted mean costs were £1066, £1435, £1461, and £1631 for births planned at home, in freestanding midwifery units, in alongside midwifery units, and in obstetric units, respectively (equivalent to about €1274, $1701; €1715, $2290; €1747, $2332; and €1950, $2603). Overall, and for multiparous women, planned birth at home generated the greatest mean net benefit with a 100% probability of being the optimal setting across all thresholds of cost effectiveness when perinatal outcomes were considered. There was, however, an increased incidence of adverse perinatal outcome associated with planned birth at home in nulliparous low risk women, resulting in the probability of it being the most cost effective option at a cost effectiveness threshold of £20 000 declining to 0.63. With regards to maternal outcomes in nulliparous and multiparous women, planned birth at home generated the greatest mean net benefit with a 100% probability of being the optimal setting across all thresholds of cost effectiveness. CONCLUSIONS: For multiparous women at low risk of complications, planned birth at home was the most cost effective option. For nulliparous low risk women, planned birth at home is still likely to be the most cost effective option but is associated with an increase in adverse perinatal outcomes.

Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: the Birthplace in England national prospective cohort study.

OBJECTIVE: To compare perinatal outcomes, maternal outcomes, and interventions in labour by planned place of birth at the start of care in labour for women with low risk pregnancies. DESIGN: Prospective cohort study. SETTING: England: all NHS trusts providing intrapartum care at home, all freestanding midwifery units, all alongside midwifery units (midwife led units on a hospital site with an obstetric unit), and a stratified random sample of obstetric units. PARTICIPANTS: 64,538 eligible women with a singleton, term (≥37 weeks gestation), and "booked" pregnancy who gave birth between April 2008 and April 2010. Planned caesarean sections and caesarean sections before the onset of labour and unplanned home births were excluded. MAIN OUTCOME MEASURE: A composite primary outcome of perinatal mortality and intrapartum related neonatal morbidities (stillbirth after start of care in labour, early neonatal death, neonatal encephalopathy, meconium aspiration syndrome, brachial plexus injury, fractured humerus, or fractured clavicle) was used to compare outcomes by planned place of birth at the start of care in labour (at home, freestanding midwifery units, alongside midwifery units, and obstetric units). RESULTS: There were 250 primary outcome events and an overall weighted incidence of 4.3 per 1000 births (95% CI 3.3 to 5.5). Overall, there were no significant differences in the adjusted odds of the primary outcome for any of the non-obstetric unit settings compared with obstetric units. For nulliparous women, the odds of the primary outcome were higher for planned home births (adjusted odds ratio 1.75, 95% CI 1.07 to 2.86) but not for either midwifery unit setting. For multiparous women, there were no significant differences in the incidence of the primary outcome by planned place of birth. Interventions during labour were substantially lower in all non-obstetric unit settings. Transfers from non-obstetric unit settings were more frequent for nulliparous women (36% to 45%) than for multiparous women (9% to 13%). CONCLUSIONS: The results support a policy of offering healthy women with low risk pregnancies a choice of birth setting. Women planning birth in a midwifery unit and multiparous women planning birth at home experience fewer interventions than those planning birth in an obstetric unit with no impact on perinatal outcomes. For nulliparous women, planned home births also have fewer interventions but have poorer perinatal outcomes.

Offer and uptake of prenatal screening for Down syndrome in women from different social and ethnic backgrounds.

OBJECTIVE: To compare offer and uptake of prenatal screening for Down syndrome in women from different social and ethnic backgrounds. METHOD: A total of 4800 randomly selected women in England were sent a survey three months after they had given birth; 2960 women responded. Odds ratios (OR) for reported offer and uptake of screening comparing women by area deprivation and ethnicity were calculated. RESULTS: In all, 65% of women reported having screening; 89% reported being offered screening, and 69% of these reported taking up the offer. There was no evidence of a difference in the reported offer (adjusted OR = 0.88, 95% confidence interval (CI) 0.65-1.19, p = 0.41) or uptake (adjusted OR = 0.84, 95% CI 0.66-1.06, p = 0.15) of screening for women living in the most deprived areas compared with other women. Asian women were less likely to report being offered screening than White women (adjusted OR = 0.61, 95% CI 0.39-0.94, p = 0.02) and were less likely to take up screening when offered (adjusted OR = 0.48, 95% CI 0.33-0.72, p < 0.001). CONCLUSIONS: While most pregnant women in England are offered prenatal screening for Down syndrome, approximately 1 in 10 is not. Asian women are less likely than White women to report being offered Down syndrome screening and are less likely to have a screening test when offered.