Hydroxychloroquine as pre-exposure prophylaxis against COVID-19 infection among healthcare workers: a prospective cohort study

AbstractBackgroundCOVID-19 vaccine trials and post-implementation data suggest vaccination decreases SARS-CoV-2 infections. We examine COVID-19 vaccination’s impact on SARS-CoV-2 case rates and viral diversity among healthcare workers (HCW) during a high community prevalence period.MethodsA prospective cohort study from Boston Medical Center (BMC)’s HCW vaccination program, where staff received two doses of BNT162b2 or mRNA-1273. We included PCR-confirmed SARS-CoV-2 cases among HCWs from December 09, 2020 to February 23, 2021. Weekly SARS-CoV-2 rates per 100,000 person-day overall and by time from first injection (1-14 and >14 days) were compared with surrounding community rates. Viral genomes were sequenced from SARS CoV-2 positive samples.ResultsSARS-CoV-2 cases occurred in 1.4% (96/7109) of HCWs given at least a first dose and 0.3% (17/5913) of HCWs given both vaccine doses. Adjusted SARS-CoV-2 infection rate ratios were 0.73 (95% CI 0.53-1.00) 1-14 days and 0.18 (0.10-0.32) >14 days from first dose. HCW SARS-CoV-2 cases >14 days from initial dose compared to within 14 days were more often older (46 versus 38 years, p=0.007), Latinx (10% versus 8%, p=0.03), and asymptomatic (48% versus 11%, p=0.0002). SARS-CoV-2 rates among HCWs fell below those of the surrounding community, with a 18% versus 11% weekly decrease respectively (p=0.14). Comparison of 48 SARS-CoV-2 genomes sequenced from post-first dose cases did not indicate selection pressure towards known spike-antibody escape mutations.ConclusionsOur results indicate a positive impact of COVID-19 vaccines on SARS-CoV-2 case rates. Post-vaccination isolates did not show unusual genetic diversity or selection for mutations of concern.Main PointCases of SARS-CoV-2 among health care workers dropped rapidly with COVID-19 vaccination. Sequencing 48 breakthrough infections (overwhelmingly in 14 days after 1st dose) showed no clear sign of any differences in spike protein compared with time-matched, unvaccinated control sequences.

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Incidence and duration of incident oropharyngeal gonorrhoea and chlamydia infections among men who have sex with men: prospective cohort study

Sexually Transmitted Infections ◽

10.1136/sextrans-2020-054764 ◽

2020 ◽

pp. sextrans-2020-054764 ◽

Cited By ~ 1

Author(s):

Eric P F Chow ◽

Lenka A Vodstrcil ◽

Deborah A Williamson ◽

Kate Maddaford ◽

Jane S Hocking ◽

...

Keyword(s):

Risk Factors ◽

Cohort Study ◽

Prospective Cohort Study ◽

Median Duration ◽

Prospective Cohort ◽

Nucleic Acid Amplification ◽

Oropharyngeal Infection ◽

Duration Of Infection ◽

Sex With Men ◽

Exposure Prophylaxis

ObjectivesThis prospective cohort study aimed to determine the natural history and incidence of oropharyngeal gonorrhoea and chlamydia among a cohort of men who have sex with men (MSM) over a 12-week period, and to examine risk factors associated with incident oropharyngeal infections.MethodsMSM either aged ≥18 years and had a diagnosis of oropharyngeal gonorrhoea by nucleic acid amplification test (NAAT) in the past 3 months or aged 18–35 years who were HIV-negative taking pre-exposure prophylaxis (PrEP) were eligible for this study. Enrolled men were followed up for 12 weeks. Oropharyngeal swabs were collected at week 0 (baseline) and week 12 (end of study). Between these time points, weekly saliva specimens and the number of tongue kissing, penile–oral and insertive rimming partners were collected by post. Oropharyngeal swabs and saliva specimens were tested by NAAT for Neisseria gonorrhoeae and Chlamydia trachomatis. Poisson regression was performed to examine the risk factors (weekly number of partners) associated with incident oropharyngeal gonorrhoea.ResultsA total of 100 MSM were recruited. The incidence of oropharyngeal gonorrhoea and chlamydia was 62 (95% CI 37 to 105) and 9 (95% CI 2 to 35)/100 person-years, respectively. The median duration of incident oropharyngeal infection with gonorrhoea was 28 days (IQR=21–36, n=7). The incidence rate ratio (IRR) for oropharyngeal gonorrhoea increased with an increased number of kissing partners (IRR=1.08; 95% CI 1.03 to 1.12) an increased number of penile-oral sex partners (IRR=1.07, 95% CI 1.01 to 1.14) but not with an increased number of insertive rimming partners (IRR=1.11, 95% CI 0.96 to 1.29) or other demographic factors. The IRR and duration of incident oropharyngeal chlamydia were not calculated due to the small number of cases (n=2).ConclusionsMSM have a high incidence of oropharyngeal gonorrhoea and the median duration of infection was less than 3 months.

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Sexually transmitted infections and viral hepatitides in patients presenting for non-occupational HIV post-exposure prophylaxis: results of a prospective cohort study

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2015.10.001 ◽

2015 ◽

Vol 40 ◽

pp. 142-144 ◽

Cited By ~ 3

Author(s):

Nirojini Sivachandran ◽

Reed A.C. Siemieniuk ◽

Pauline Murphy ◽

Andrea Sharp ◽

Christine Walach ◽

...

Keyword(s):

Cohort Study ◽

Sexually Transmitted Infections ◽

Prospective Cohort Study ◽

Prospective Cohort ◽

Post Exposure Prophylaxis ◽

Sexually Transmitted ◽

Post Exposure ◽

Exposure Prophylaxis

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Seasonal influenza risk in hospital healthcare workers is more strongly associated with household than occupational exposures: results from a prospective cohort study in Berlin, Germany, 2006/07

BMC Infectious Diseases ◽

10.1186/1471-2334-10-8 ◽

2010 ◽

Vol 10 (1) ◽

Cited By ~ 48

Author(s):

Chris J Williams ◽

Brunhilde Schweiger ◽

Genia Diner ◽

Frank Gerlach ◽

Frank Haaman ◽

...

Keyword(s):

Cohort Study ◽

Prospective Cohort Study ◽

Prospective Cohort ◽

Healthcare Workers ◽

Seasonal Influenza ◽

Occupational Exposures

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Incidence of Asymptomatic and Symptomatic Influenza Among Healthcare Workers: A Multicenter Prospective Cohort Study

Clinical Infectious Diseases ◽

10.1093/cid/ciaa1109 ◽

2020 ◽

Author(s):

Thomas Bénet ◽

Sélilah Amour ◽

Martine Valette ◽

Mitra Saadatian-Elahi ◽

Ludwig Serge Aho-Glélé ◽

...

Keyword(s):

Cohort Study ◽

Prospective Cohort Study ◽

Cumulative Incidence ◽

Prospective Cohort ◽

Healthcare Workers ◽

Control Measures ◽

T1 And T2 ◽

Multicenter Prospective Cohort Study ◽

Multicenter Prospective Cohort

Abstract Background Influenza is an important cause of viral hospital-acquired infection involving patients, healthcare workers (HCW), and visitors. The frequency of asymptomatic influenza among HCW with possible subsequent transmission is poorly described. The objective is to determine the cumulative incidence of asymptomatic, paucisymptomatic, and symptomatic influenza among HCW. Method A multicenter prospective cohort study was done in 5 French university hospitals, including 289 HCW during the 2016–2017 influenza season. HCW had 3 physical examinations (time [T] 0, before epidemic onset; T.1, before epidemic peak; T.2, T.3, after epidemic peak). A blood sample was taken each time for influenza serology and a nasal swab was collected at T1 and T2 for influenza detection by polymerase chain reaction (PCR). Positive influenza was defined as either a positive influenza PCR, and/or virus-specific seroconversion against influenza A, the only circulating virus, with no vaccination record during follow-up. Symptoms were self-reported daily between T1 and T2. Cumulative incidence of influenza was stratified by clinical presentation per 100 HCW. Results Of the 289 HCW included, 278 (96%) completed the entire follow-up. Overall, 62 HCW had evidence of influenza of whom 46.8% were asymptomatic, 41.9% were paucisymptomatic, and 11.3% were symptomatic. Cumulative influenza incidence was 22.3% (95% confidence interval [CI]: 17.4%–27.2%). Cumulative incidence of asymptomatic influenza was 5.8% (95% CI: 3.3%–9.2%), 13.7% (95% CI: 9.9%–18.2%) for paucisymptomatic influenza, and 2.9% (95% CI: 1.3%–5.5%) for symptomatic influenza. Conclusions Asymptomatic and paucisymptomatic influenza were frequent among HCW, representing 47% and 42% of the influenza burden, respectively. These findings highlight the importance of systematic implementation of infection control measures among HCW regardless of respiratory symptoms from preventing nosocomial transmission of influenza. Clinical Trials Registration NCT02868658.

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