| 1. |
- Alsved, Malin, et al.
(författare)
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SARS-CoV-2 in exhaled aerosol particles from covid-19 cases and its association to household transmission
- 2022
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Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 75:1, s. 50-56
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Covid-19 transmission via exhaled aerosol particles has been considered an important route for the spread of infection, especially during super-spreading events involving loud talking or singing. However, no study has previously linked measurements of viral aerosol emissions to transmission rates.METHODS: During Feb-Mar 2021, covid-19 cases that were close to symptom onset were visited with a mobile laboratory for collection of exhaled aerosol particles during breathing, talking and singing, respectively, and of nasopharyngeal and saliva samples. Aerosol samples were collected using a BioSpot-VIVAS and a NIOSH bc-251 two-stage cyclone, and all samples were analyzed by RT-qPCR for SARS-CoV-2 RNA detection. We compared transmission rates between households with aerosol-positive and aerosol-negative index cases.RESULTS: SARS-CoV-2 RNA was detected in at least one aerosol sample from 19 of 38 (50%) included cases. The odds ratio of finding positive aerosol samples decreased with each day from symptom onset (OR 0.55, 95CI 0.30-1.0, p=0.049). The highest number of positive aerosol samples were from singing, 16 (42%), followed by talking, 11 (30%), and the least from breathing, 3 (8%). Index cases were identified for 13 households with 31 exposed contacts. Higher transmission rates were observed in households with aerosol-positive index cases, 10/16 infected (63%), compared to households with aerosol-negative index cases, 4/15 infected (27%) (Chi-square test, p=0.045).CONCLUSIONS: Covid-19 cases were more likely to exhale SARS-CoV-2-containing aerosol particles close to symptom onset and during singing or talking as compared to breathing. This study supports that individuals with SARS-CoV-2 in exhaled aerosols are more likely to transmit covid-19.
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| 2. |
- Alsved, Malin, et al.
(författare)
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Sources of Airborne Norovirus in Hospital Outbreaks
- 2020
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Ingår i: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1537-6591 .- 1058-4838. ; 70:10, s. 2023-2028
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Noroviruses are the major cause of viral gastroenteritis. Disease transmission is difficult to prevent and outbreaks in healthcare facilities commonly occur. Contact with infected persons and contaminated environments are believed to be the main routes of transmission. However, noroviruses have recently been found in aerosols and airborne transmission has been suggested. The aim of our study was to investigate associations between symptoms of gastroenteritis and presence of airborne norovirus, and to investigate the size of norovirus carrying particles.METHODS: Air sampling was repeatedly performed close to 26 patients with norovirus infections. Samples were analysed for norovirus RNA by RT-qPCR. The times since the patients' last episodes of vomiting and diarrhoea were recorded. Size separating aerosol particle collection was also performed in ward corridors.RESULTS: Norovirus RNA was found in 21 (24%) of 86 air samples from 10 different patients. Only air samples during outbreaks, or before a succeeding outbreak, tested positive for norovirus RNA. Airborne norovirus RNA was also strongly associated with a shorter time period since the last vomiting episode (odds ratio 8.1, p=0.04 within 3 hours since the last vomiting episode). The concentration of airborne norovirus ranged from 5-215 copies/m3, and detectable amounts of norovirus RNA were found in particles <0.95 µm and >4.51 µm.CONCLUSIONS: The results suggest that recent vomiting is the major source of airborne norovirus and imply a connection between airborne norovirus and outbreaks. The presence of norovirus RNA in submicrometre particles indicates that airborne transmission can be an important transmission route.
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| 3. |
- Hassan, Amin S, et al.
(författare)
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A Stronger Innate Immune Response During Hyperacute HIV-1 Infection is associated with ACUTE retroviral syndrome
- 2021
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Ingår i: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1537-6591 .- 1058-4838. ; 73:5, s. 832-841
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Acute retroviral syndrome (ARS) is associated with HIV-1 subtype and disease progression, but the underlying immunopathological pathways are poorly understood. We aimed to elucidate associations between innate immune responses during hyperacute HIV-1 infection (hAHI) and ARS.METHODS: Plasma samples obtained from volunteers (≥18.0 years) before and during hAHI, defined as HIV-1 antibody negative and RNA or p24 antigen positive from Kenya, Rwanda, Uganda, Zambia and Sweden were analysed. Forty soluble innate immune markers were measured using multiplexed assays. Immune responses were differentiated into volunteers with stronger and comparatively weaker responses using principal component analysis. Presence or absence of ARS was defined based on eleven symptoms using latent class analysis. Logistic regression was used to determine associations between immune responses and ARS.RESULTS: Of 55 volunteers, 31 (56%) had ARS. Volunteers with stronger immune responses (n=36 [65%]) had increased odds of ARS which was independent of HIV-1 subtype, age, and risk group (adjusted odds ratio, 7.1 [95% CI: 1.7-28.8], p=0.003). IP-10 was fourteen-fold higher during hAHI, elevated in seven of the eleven symptoms, and independently associated with ARS. IP-10 threshold >466.0 pg/mL differentiated stronger immune responses with a sensitivity of 84.2% (95% CI: 60.4-96.6) and specificity of 100.0% (95% CI: 90.3-100.0).CONCLUSIONS: A stronger innate immune response during hAHI was associated with ARS. Plasma IP-10 may be a candidate biomarker of stronger innate immunity. Our findings provide further insights on innate immune responses in regulating ARS and may inform the design of vaccine candidates harnessing innate immunity.
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| 4. |
- Inghammar, Malin, et al.
(författare)
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Proton-Pump Inhibitor Use and the Risk of Community-Associated Clostridium difficile Infection
- 2021
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Ingår i: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1058-4838 .- 1537-6591. ; 72:12, s. 1084-1089
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Tidskriftsartikel (refereegranskat)abstract
- Background: Proton-pump inhibitors (PPIs) have been reported to increase the risk of community-associated Clostridium difficile infection (CDI), but the association remains disputed. Methods: A nationwide cohort study among adults in Denmark, 2010-2013, linking register data on C. difficile testing, filled prescriptions, and patient characteristics. All incident episodes of community-associated CDI (ie, positive culture, molecular assay, or toxin test in individuals without previous hospitalization in the prior 12 weeks and without a positive test for C. difficile in the prior 8 weeks) were identified in the Danish National Microbiological Database. Self-controlled case-series analyses were used to estimate incidence rate ratios (IRRs) for community-associated CDI, comparing periods with and without exposure to PPIs. By design, models took fixed confounders such as chronic disease, genetics, and socioeconomic status into account; further, time-varying confounders, including hospital stay and antibiotic and corticosteroid use were adjusted for. Results: 3583 episodes of community-associated CDI were identified, of which 964 occurred during current use of PPIs, 324 occurred 0-6 months after treatment cessation, 123 occurred 6-12 months after treatment cessation, and 2172 occurred during time periods without use of PPIs. The adjusted IRR was 2.03 (95% confidence interval, 1.74-2.36), comparing use of PPI with nonuse. The increased risk remained elevated in later time periods: 1.54 (1.31-1.80) for 0-6 months, 1.24 (1.00-1.53) for 6-12 months after current use. Conclusions: Use of PPIs was associated with moderately increased risk of community-associated CDI. The risk remained elevated up to 1 year after PPI treatment had ended.
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| 5. |
- Jansåker, Filip, et al.
(författare)
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All-cause Mortality Due to Bacteremia during a 60-Day Non-Physician Healthcare Worker Strike
- 2021
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Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 73:7, s. 1758-1761
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Tidskriftsartikel (refereegranskat)abstract
- This study explored all-cause mortality of bacteremia diagnosed during a 60-day non-physician healthcare worker strike in 2008. A significant change, with 5.0% (95% confidence interval [CI] 1.2-8.7%, P < .01) absolute risk increase, was seen in 90-day mortality during the strike (n = 598) compared with the rest of the study period 2000-2015 (n = 75 647).
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| 6. |
- Nibell, Olof, et al.
(författare)
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Oral fluoroquinolone use and the risk of acute liver injury: a nationwide cohort study
- 2021
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Ingår i: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1537-6591 .- 1058-4838.
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Tidskriftsartikel (refereegranskat)abstract
- Antibiotics are considered to be among the most frequent causes of drug-related acute liver injury (ALI). Although many ALIs have mild and reversible clinical outcomes, there is substantial risk of severe reactions leading to acute liver failure, need for liver transplant, and death. Recent studies have raised concerns of hepatotoxic potential related to the use of fluoroquinolones.MethodsThis study examined the risk of ALI associated with oral fluoroquinolone treatment compared with amoxicillin (419 930 courses, propensity score matched 1:1). The information on drug use was collected from a national, registry-based cohort derived from all Swedish adults aged 40–85 years.ResultsDuring a follow-up period of 60 days, users of oral fluoroquinolones had a >2-fold risk of ALI compared to users of amoxicillin (hazard ratio, 2.32 [95% confidence interval {CI}, 1.01–5.35). The adjusted absolute risk difference for use of fluoroquinolones as compared to amoxicillin was 4.94 (95% CI, .04–16.3) per 1 million episodes.ConclusionsIn this propensity score–matched study, fluoroquinolone treatment was associated with an increased risk of ALI in the first 2 months after starting treatment.
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| 7. |
- Nibell, Olof, et al.
(författare)
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Reply to Rezahosseini
- 2022
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Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 74:12, s. 2262-2262
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 8. |
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| 9. |
- Rasmussen, Magnus, et al.
(författare)
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One Scoring System Does Not Fit All Healthcare Settings
- 2022
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Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 74:1, s. 166-167
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Tidskriftsartikel (refereegranskat)
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| 10. |
- Thuresson, Sara, et al.
(författare)
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Airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Hospitals : Effects of Aerosol-Generating Procedures, HEPA-Filtration Units, Patient Viral Load, and Physical Distance
- 2022
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Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 75:1, s. 89-96
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Transmission of coronavirus disease 2019 (COVID-19) can occur through inhalation of fine droplets or aerosols containing infectious virus. The objective of this study was to identify situations, patient characteristics, environmental parameters, and aerosol-generating procedures (AGPs) associated with airborne severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus.METHODS: Air samples were collected near hospitalized COVID-19 patients and analyzed by RT-qPCR. Results were related to distance to the patient, most recent patient diagnostic PCR cycle threshold (Ct) value, room ventilation, and ongoing potential AGPs.RESULTS: In total, 310 air samples were collected; of these, 26 (8%) were positive for SARS-CoV-2. Of the 231 samples from patient rooms, 22 (10%) were positive for SARS-CoV-2. Positive air samples were associated with a low patient Ct value (OR, 5.0 for Ct <25 vs >25; P = .01; 95% CI: 1.18-29.5) and a shorter physical distance to the patient (OR, 2.0 for every meter closer to the patient; P = .05; 95% CI: 1.0-3.8). A mobile HEPA-filtration unit in the room decreased the proportion of positive samples (OR, .3; P = .02; 95% CI: .12-.98). No association was observed between SARS-CoV-2-positive air samples and mechanical ventilation, high-flow nasal cannula, nebulizer treatment, or noninvasive ventilation. An association was found with positive expiratory pressure training (P < .01) and a trend towards an association for airway manipulation, including bronchoscopies and in- and extubations.CONCLUSIONS: Our results show that major risk factors for airborne SARS-CoV-2 include short physical distance, high patient viral load, and poor room ventilation. AGPs, as traditionally defined, seem to be of secondary importance.
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