Vaccine-Preventable Disease Outbreaks among Healthcare Workers: A Scoping Review.

BACKGROUND: Outbreaks of vaccine preventable diseases (VPDs) in health care workers (HCWs) can result in morbidity and mortality and cause significant disruptions to health care services, patients and visitors as well as an added burden on the health system. This scoping review is aimed to describe the epidemiology of VPD outbreaks in HCW, caused by diseases which are prevented by the ten vaccines recommended by World Health Organization (WHO) for HCWs. METHODS: In April 2022 CINAHL, MEDLINE, Global Health and EMBASE were searched for all articles reporting on VPD outbreaks in HCWs since the year 2000. Articles were included regardless of language and study type. Clinical and epidemiological characteristics of VPD outbreaks were described. RESULTS: Our search found 9363 articles, of which 216 met inclusion criteria. Studies describing six of the ten VPDs were found: influenza, measles, varicella, tuberculosis, pertussis and rubella. Most articles (93%) were from high- and upper middle-income countries. While most outbreaks occurred in hospitals, several influenza outbreaks were reported in long term care facilities. Based on available data, vaccination rates amongst HCWs were rarely reported. CONCLUSION: We describe several VPD outbreaks in HCWs from 2000 to April 2022. The review emphasises the need to understand the factors influencing outbreaks in HCWs and highlight importance of vaccination amongst HCWs.

Treatment of multidrug-resistant or rifampicin-resistant tuberculosis with an all-oral 9-month regimen containing linezolid or ethionamide in South Africa: A retrospective cohort study.

BACKGROUND: In 2019, the South African tuberculosis program replaced ethionamide with linezolid as a part of an all-oral 9-month regimen. We evaluated treatment outcomes for patients assigned to regimens including linezolid in 2019 and ethionamide in 2017. METHOD: This retrospective cohort study included patients treated for multi-drug resistant/rifampicin-resistant tuberculosis throughout South Africa between 1 Jan to 31 Dec 2017 and from 1 Jan to 31 Dec 2019. The cohort treated with a 9-month regimen containing ethionamide for four months, was compared with a cohort treated with a 9-month regimen containing linezolid for two months. The regimens were otherwise identical. Inverse probability weighting of propensity scores was used to adjust for potential confounding. A log-binomial regression model was used to estimate adjusted relative risk (aRR) comparing 24-month outcomes between cohorts including treatment success, death, loss to follow up, and treatment failure. Adverse event data were available for the linezolid cohort. FINDINGS: 817 patients were included in the cohort receiving ethionamide and 4244 in the cohort receiving linezolid. No evidence for a difference was observed between linezolid and ethionamide regimens for treatment success (aRR = 0·96, 95%CI 0·91-1·01), death (aRR = 1·01, 95%CI 0·87-1·17) or treatment failure (aRR = 0·87, 95%CI 0·44-1·75). Loss to follow up was more common in the linezolid group, although estimates were imprecise (aRR = 1·22, 95%CI 0·99-1·50). INTERPRETATION: No significant differences in treatment success and survival were observed with substitution of linezolid for ethionamide as a part of an all-oral 9-month regimen. Linezolid is an acceptable alternative to ethionamide in this shorter regimen for treatment of multi-drug resistant/rifampicin resistant tuberculosis.

The Safety and Tolerability of Linezolid in Novel Short-Course Regimens Containing Bedaquiline, Pretomanid, and Linezolid to Treat Rifampicin-Resistant Tuberculosis: An Individual Patient Data Meta-analysis.

BACKGROUND: Effectiveness, safety, tolerability, and adherence are critical considerations in shifting to shorter tuberculosis (TB) regimens. Novel 6-month oral regimens that include bedaquiline (B), pretomanid (Pa), and linezolid (L), with or without a fourth drug, have been shown to be as or more effective than the established longer regimens for the treatment of multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB). We aimed to evaluate the safety and tolerability of linezolid in BPaL-containing regimens for the treatment of MDR/RR-TB among recently completed clinical trials. METHODS: A review and meta-analysis was undertaken including published and unpublished data from clinical trials, conducted between 2010 and 2021, that evaluated regimens containing BPaL for the treatment of MDR/RR-TB. Individual patient data were obtained. For each BPaL-containing regimen, we evaluated the frequency and severity of treatment-related adverse events. The risk difference of adverse events for each regimen was calculated, in comparison to patients assigned to receiving the lowest cumulative exposure of linezolid. RESULTS: Data from 3 clinical trials investigating 8 unique BPaL-containing regimens were included, comprising a total of 591 participants. Adverse events were more frequent in groups randomized to a higher cumulative linezolid dose. Among patients who were randomized to a daily dose of 1200 mg linezolid, 68 of 195 (35%) experienced a grade 3-4 adverse event versus 89 of 396 (22%) patients receiving BPaL-containing regimens containing 600 mg linezolid. CONCLUSIONS: Regimens containing BPaL were relatively well tolerated when they included a daily linezolid dose of 600 mg. These novel regimens promise to improve the tolerability of treatment for MDR/RR-TB.

The prevalence of SARS-CoV-2 antibodies in quarantine workers and high-risk communities in Vietnam.

Objective: The aim of this study was to determine the seroprevalence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antibodies in high-risk communities and quarantine workers in Vietnam. Methods: The prevalence of SARS-CoV-2 antibodies was measured in household contacts, close contacts, community members, and migrant workers from two sub-communes in which COVID-19 outbreaks occurred in early 2021: Bac Ma 1 and Tien. The prevalence of SARS-CoV-2 antibodies was also evaluated among quarantine workers at two facilities responsible for quarantining of contacts of COVID-19 cases. Results: Among 2069 participants from the two sub-communes, six individuals (0.3%) had detectable SARS-CoV-2 antibodies despite no history of COVID-19. This included one Vietnamese migrant worker, two community members, two household contacts, and one close contact of known COVID-19 cases. Among 50 workers at two COVID-19 quarantine facilities, including 15 health care workers (HCWs), one of the HCWs tested positive for SARS-CoV-2 antibodies (1/50, 2.0%) despite no known disease. Conclusion: The prevalence of SARS-CoV-2 antibodies was low in Vietnamese 'hotspots', suggesting limited community transmission.

Melioidosis of the central nervous system; impact of the bimABm allele on patient presentation and outcome.

BACKGROUND: The autotransporter protein Burkholderia intracellular motility A (BimA) facilitates the entry of Burkholderia pseudomallei into the central nervous system (CNS) in mouse models of melioidosis. Its role in the pathogenesis of human cases of CNS melioidosis is incompletely defined. METHODS: Consecutive culture-confirmed cases of melioidosis at two sites in tropical Australia after 1989 were reviewed. Demographic, clinical and radiological data of the patients with CNS melioidosis were recorded. The bimA allele (bimABm or bimABp) of the B. pseudomallei isolated from each patient was determined. RESULTS: Of the 1587 cases diagnosed at the two sites during the study period, 52 (3.3%) had confirmed CNS melioidosis; 20 (38.5%) had a brain abscess, 18 (34.6%) had encephalomyelitis, 4 (7.7%) had isolated meningitis and 10 (19.2%) had extra-meningeal disease. Among the 52 patients, there were 8 (15.4%) deaths; 17/44 (38.6%) survivors had residual disability. The bimA allele was characterized in 47/52; 17/47 (36.2%) had the bimABm allele and 30 (63.8%) had the bimABp allele. Patients with a bimABm variant were more likely to have a predominantly neurological presentation (odds ratio (OR) (95% confidence interval (CI)): 5.60 (1.52-20.61), p=0.01), to have brainstem involvement (OR (95%CI): 7.33 (1.92-27.95), p=0.004) and to have encephalomyelitis (OR (95%CI): 4.69 (1.30-16.95), p=0.02. Patients with a bimABm variant were more likely to die or have residual disability (odds ratio (95%CI): 4.88 (1.28-18.57), p=0.01). CONCLUSIONS: The bimA allele of B. pseudomallei has a significant impact on the clinical presentation and outcome of patients with CNS melioidosis.

Retrospective Cohort Study of Effects of the COVID-19 Pandemic on Tuberculosis Notifications, Vietnam, 2020.

We evaluated the effects of the coronavirus disease pandemic on diagnosis of and treatment for tuberculosis (TB) in Vietnam. We obtained quarterly notifications for TB and multidrug-resistant/rifampin-resistant (MDR/RR) TB from 2015-2020 and evaluated changes in monthly TB case notifications. We used an interrupted time series to assess the change in notifications and treatment outcomes. Overall, TB case notifications were 8% lower in 2020 than in 2019; MDR/RR TB notifications were 1% lower. TB case notifications decreased by 364 (95% CI -1,236 to 508) notifications per quarter and MDR/RR TB by 1 (95% CI -129 to 132) notification per quarter. The proportion of successful TB treatment outcomes decreased by 0.1% per quarter (95% CI -1.1% to 0.8%) in 2020 compared with previous years. Our study suggests that Vietnam was able to maintain its TB response in 2020, despite the pandemic.

Introducing 1,3-beta-d-glucan for screening and diagnosis of invasive fungal diseases in Australian high-risk haematology patients: is there a clinical benefit?

BACKGROUND: Early, accurate diagnosis of invasive fungal disease (IFD) improves clinical outcomes. 1,3-beta-d-glucan (BDG) (Fungitell, Associates of Cape Cod, Inc., Falmouth, MA, USA) detection can improve IFD diagnosis but has been unavailable in Australia. AIMS: To assess performance of serum BDG for IFD diagnosis in a high-risk Australian haematology population. METHODS: We compared the diagnostic value of weekly screening of serum BDG with screening by Aspergillus polymerase chain reaction and Aspergillus galactomannan in 57 at-risk episodes for the diagnosis of IFD (proven, probable, possible IFD). RESULTS: IFD episodes were: proven (n = 4); probable (n = 4); possible (n = 18); and no IFD (n = 31). Using two consecutive BDG results of ≥80 pg/mL to call a result 'positive', the sensitivity, specificity, positive predictive value and negative predictive value was 37.5%, 64.5%, 23.1% and 80.7% respectively. For invasive aspergillosis, test performance increased to 50%, 90.3%, 57.1% and 87.5% respectively if any two of serum BDG/Aspergillus polymerase chain reaction/galactomannan yielded a 'positive' result. In proven/probable IFD, five of eight episodes returned a positive BDG result earlier (mean 6.6 days) than other diagnostic tests. False-negative BDG results occurred in three of eight episodes of proven/probable IFD, and false positive in 10 of 31 patients with no IFD. Erratic patterns of BDG values predicted false positive results (P = 0.03). Using serum BDG results, possible IFD were reassigned to either 'no' or 'probable' IFD in 44% cases. Empiric anti-fungal therapy use may have been optimised by BDG monitoring in 38.5% of courses. CONCLUSIONS: The BDG assay can add diagnostic speed and value but was hampered by low sensitivity and positive predictive value in Australian haematology patients.

The utility of SARS-CoV-2-specific serology in COVID-19 diagnosis.

INTRODUCTION: In May 2020, The Communicable Diseases Network of Australia (CDNA) case definition introduced serological criteria to support the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We present findings that support the utility of SARS-CoV-2-specific serology for public health investigations. METHODS: From 24 January to 31 July 2020, the following information was collected from individuals with positive SARS-CoV-2-specific immunofluorescence antibody tests: history of contact with COVID-19 cases; recent travel; symptoms consistent with COVID-19; and SARS-CoV-2 nucleic acid testing (NAT) results. Individuals were classified as confirmed or probable by CDNA criteria or additionally as possible (SARS-CoV-2-specific IgG positive with compatible symptoms or epidemiologic risk) or indeterminate (SARS-CoV-2-specific IgA/IgM positive only) cases. RESULTS: A total of 10,595 individuals were tested in the six-month period. Of these, 9.8% (1,037) individuals had positive SARS-CoV-2-specific serology of which 566 (53.6%) were NAT-confirmed COVID-19 cases and 286 (27.6%) were part of a cruise ship outbreak sero-survey. The remaining 185 individuals (NAT negative) were individually classified as serologically confirmed (4, 0.4%), probable (72, 6.9%) possible (66, 6.4%) and indeterminate (38, 3.7%) cases. Maternal antibody transfer was inferred in one infant and four were unclassified. CONCLUSION: SARS-CoV-2-specific serology is a key diagnostic tool for retrospective identification of COVID-19 infection. Implications for public health: SARS-CoV-2 specific serology can enhance the ability to find cases, link missing cases in clusters of infection and identify the epidemiological extent of SARS-CoV-2 outbreaks. A combination of epidemiological criteria, clinical criteria and a quantitative serological test can be used as an adjunct to classify SARS-CoV-2 cases. Our study confirms the low level of community transmission in NSW during the first year of the COVID-19 pandemic.

Sero-Prevalence of SARS-CoV-2 Antibodies in High-Risk Populations in Vietnam.

As a response to the coronavirus disease 2019 (COVID-19) pandemic, Vietnam enforced strict quarantine, contact tracing and physical distancing policies resulting in one of the lowest numbers of individuals infected with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) globally. This study aimed to determine the prevalence of SARS-CoV-2 antibody positivity among high-risk populations in Vietnam. A prevalence survey was undertaken within four communities in Vietnam, where at least two COVID-19 cases had been confirmed. Participants were classified according to the location of exposure: household contacts, close contacts, community members, and healthcare workers (HCWs) responsible for treating COVID-19 cases. Participants completed a baseline questionnaire and SARS-CoV-2 IgG antibodies were quantified using a commercial assay. A total of 3049 community members and 149 health care workers consented to the study. Among 13 individuals who were seropositive (0.4%), five household contacts (5/27, 18.5%), one close contact (1/53, 1.9%), and seven community members (7/2954, 0.2%) had detectable SARS-CoV-2 antibodies. All HCWs were negative for SARS-CoV-2 antibodies. Participants were tested a median of 15.1 (interquartile range from 14.9 to 15.2) weeks after exposure. Our study found a low prevalence of SARS-CoV-2 antibodies in high-risk communities and healthcare workers in communities in Vietnam with known COVID-19 cases.

The Implementation of Mass-Vaccination against SARS-CoV-2: A Systematic Review of Existing Strategies and Guidelines.

The global drive to vaccinate against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) began in December 2020 with countries in Europe, Middle East, and North America leading the roll out of a mass-vaccination program. This systematic review synthesised all available English-language guidelines and research regarding mass-vaccination for COVID-19 until 1 March 2021-the first three months of the global mass-vaccination effort. Data were extracted from national websites, PubMed, Embase, Medline and medRxiv, including peer and non-peer review research findings. A total of 15 national policy documents were included. Policies were summarised according to the World Health Organisation (WHO) framework for mass vaccination. All included policies prioritised front-line health care workers and the elderly. Limited information was available regarding staffing, cold chain, communication strategies and infrastructure requirements for effective vaccine delivery. A total of 26 research studies were identified, reporting roll-out strategies, vaccine uptake and reasons for refusal, adverse effects, and real-life estimates of efficacy. Early data showed a reduction in SARS-CoV-2 cases, hospitalisation and deaths in settings with good coverage. Very low rates of vaccine-related serious adverse events were observed. These findings provide an overview of current practice and early outcomes of COVID-19 mass-vaccination, guiding countries where roll-out is yet to commence.

Crusted scabies; a 2-year prospective study from the Northern Territory of Australia.

BACKGROUND: Scabies is listed as a neglected tropical disease by the World Health Organization. Crusted scabies affects vulnerable and immunosuppressed individuals and is highly contagious because of the enormous number of Sarcoptes scabiei mites present in the hyperkeratotic skin. Undiagnosed and untreated crusted scabies cases can result in outbreaks of scabies in residential facilities and can also undermine the success of scabies mass drug administration programs. METHODS AND PRINCIPAL FINDINGS: Crusted scabies became a formally notifiable disease in the Northern Territory of Australia in 2016. We conducted a 2-year prospective study of crusted scabies cases notified between March 2016 and February 2018, with subsequent follow up for 22 months. Demographics, clinical and laboratory data, treatment and outcomes were analysed, with cases classified by severity of disease. Over the 2-year study period, 80 patients had 92 episodes of crusted scabies; 35 (38%) were Grade 1 crusted scabies, 36 (39%) Grade 2 and 21 (23%) Grade 3. Median age was 47 years, 47 (59%) were female, 76 (95%) Indigenous Australians and 57 (71%) from remote Indigenous communities. Half the patients were diabetic and 18 (23%) were on dialysis for end-stage kidney failure. Thirteen (16%) patients had no comorbidities, and these were more likely to have Grade 3 disease. Eosinophilia was present in 60% and high immunoglobulin E in 94%. Bacteremia occurred in 11 episodes resulting in one fatality with methicillin-susceptible Staphylococcus aureus bacteremia. Two other deaths occurred during admission and 10 others died subsequent to discharge consequent to comorbidities. Treatment generally followed the recommended guidelines, with 3, 5 or 7 doses of oral ivermectin depending on the documented grade of crusted scabies, together with daily alternating topical scabicides and topical keratolytic cream. While response to this therapy was usually excellent, there were 33 episodes of recurrent crusted scabies with the majority attributed to new infection subsequent to return to a scabies-endemic community. CONCLUSIONS: Crusted scabies can be successfully treated with aggressive guideline-based therapy, but high mortality remains from underlying comorbidities. Reinfection on return to community is common while scabies remains endemic.

Screening and prevention for latent tuberculosis in immunosuppressed patients at risk for tuberculosis: a systematic review of clinical practice guidelines.

OBJECTIVE: Immunosuppressed individuals are at a high risk of latent tuberculosis infection (LTBI) and clinical practice guidelines for the screening and management of LTBI in at-risk patients have been developed. We assessed the scope, quality and consistency of clinical practice guidelines on screening for LTBI and the prevention of tuberculosis infection (TB) in high-risk patient populations. DESIGN: We conducted a systematic review of clinical practice guidelines. Methodological quality of these guidelines was assessed using the Appraisal of Guidelines for Research and Education (AGREE) II instrument. Textual synthesis was used to summarise and compare the recommendations. DATA SOURCES: Electronic databases (MEDLINE, EMBASE, PsycINFO) and guideline registries were searched from inception to December 2017. RESULTS: Thirty-eight guidelines were included. Nineteen focused on patients receiving medical immunosuppression, seven on transplantation, three on patients with HIV and nine were generalised across all at risk populations. Most guidelines (n=32, 84%) used a systematic approach to identify and appraise the evidence. The methodological quality of the guidelines varied with the overall mean AGREE II scores ranging from 35% to 80%. Guidelines performed poorly in terms of editorial independence (average score 35%, range 0%-92%); however, most were robust in defining their scope and purpose (average score 80%, range 56%-100%). Guidelines recommended either or both the tuberculin skin test and the interferon gamma release assay for screening. Treatment of LTBI with isoniazid was consistently recommended. CONCLUSION: Clinical practice guidelines on LTBI vary in quality and scope. The recommendations for screening varied across guidelines, while recommendations for treatment were largely consistent. Improving the consistency and quality of guidelines may help to optimise the screening and management of LTBI for improved patient outcomes.

Successful treatment of Listeria monocytogenes prosthetic valve endocarditis using rifampicin and benzylpenicillin in combination with valve replacement.

Introduction.Listeria monocytogenes is an uncommon cause of prosthetic valve endocarditis (PVE). Recommended antimicrobial therapy typically includes intravenous ß-lactams with or without synergistic aminoglycosides. In vitro studies have previously identified antagonism when rifampicin has been used in combination with ß-lactams. However, in vivo data of rifampicin use are limited despite its enhanced anti-biofilm activity. Case presentation. A 63-year-old male presented with fever and back pain. L. monocytogenes bacteraemia and bioprosthetic aortic valve endocarditis was confirmed, along with spinal discitis and osteomyelitis. He was successfully treated with benzylpenicillin and rifampicin, in conjunction with valve replacement. Conclusion. Rifampicin remains an alternate agent to use, when there are contraindications to traditional aminoglycoside therapy. Further data on rifampicin use in L. monocytogenes PVE are awaited.

A Systematic Review of Post-traumatic Stress Disorder and Depression Amongst Iraqi Refugees Located in Western Countries.

A systematic review of literature reporting prevalence rates of posttraumatic stress disorder (PTSD) and depression amongst community samples of resettled Iraqi refugees was undertaken. A search of the electronic databases of Medline, PsychINFO, CINAHL, PILOTS, Scopus, and Cochrane, up to November 2013 was conducted. Following the application of the inclusion and exclusion criteria, eight empirical papers were included in the review and analysis. Specifically, six studies reported on PTSD prevalence (total n = 1,912), which ranged from 8 to 37.2 % and seven studies reported on rates of depression (total n = 1,647) noted to be 28.3 to 75 %. The overall interobserver agreement for the methodological quality assessment was good to excellent with a Kappa coefficient of 0.64. Iraqi refugees continue to represent one of the largest groups being resettled worldwide. This systematic review indicates that prevalence of PTSD and depression is high and should be taken into consideration when developing mental health early intervention and treatment services.

The effects of climate variables on the outbreak of dengue in Queensland 2008-2009.

Outbreaks of dengue occur in Queensland, Australia nearly every summer. In 2008-2009, there was an unusually large, protracted outbreak of dengue, comprised of 1,200 cases. We investigated the weather variables and their contribution to the 2008-2009 dengue outbreak in Queensland. Case data were obtained from the Communicable Disease Branch of Queensland Health for 2000-2010 for the towns of Cairns and Townsville. Monthly weather data (rainfall, maximum temperature, minimum temperature) and Southern Oscillation Index (SOI) was obtained from the Bureau of Meteorology (BOM). We used a negative binomial model to test associations between these variables and dengue. Lagged models were also created for one, two and three months. Our models suggest all weather variables but not the SOI were associated with dengue in both Cairns and Townsville, without a lag (p<0.01). No significant lag was seen with the weather variables. Rainfall and temperature preceding the 2008-2009 outbreak were also not significantly different (p<0.01) from other years. Short-term (non-lagged) weather variables were associated with the number of dengue cases in Cairns and Townsville. No lag was seen and no association was seen between the SOI and the number of dengue cases, which suggests there may be limited potential to predict large dengue outbreaks using climate variability. The large outbreak in 2008-2009 may have been driven by other, non-weather factors in addition to the immediate weather effect.