Dispersion of SARS-CoV-2 in air surrounding COVID-19-infected individuals with mild symptoms.

Since the beginning of the pandemic, the transmission modes of SARS-CoV-2-particularly the role of aerosol transmission-have been much debated. Accumulating evidence suggests that SARS-CoV-2 can be transmitted by aerosols, and not only via larger respiratory droplets. In this study, we quantified SARS-CoV-2 in air surrounding 14 test subjects in a controlled setting. All subjects had SARS-CoV-2 infection confirmed by a recent positive PCR test and had mild symptoms when included in the study. RT-PCR and cell culture analyses were performed on air samples collected at distances of one, two, and four meters from test subjects. Oronasopharyngeal samples were taken from consenting test subjects and analyzed by RT-PCR. Additionally, total aerosol particles were quantified during air sampling trials. Air viral concentrations at one-meter distance were significantly correlated with both viral loads in the upper airways, mild coughing, and fever. One sample collected at four-meter distance was RT-PCR positive. No samples were successfully cultured. The results reported here have potential application for SARS-CoV-2 detection and monitoring schemes, and for increasing our understanding of SARS-CoV-2 transmission dynamics. Practical implications. In this study, quantification of SARS-CoV-2 in air was performed around infected persons with mild symptoms. Such persons may go longer before they are diagnosed and may thus be a disproportionately important epidemiological group. By correlating viral concentrations in air with behavior and symptoms, we identify potential risk factors for viral dissemination in indoor environments. We also show that quantification of total aerosol particles is not a useful strategy for monitoring SARS-CoV-2 in indoor environments.

Substance abuse-related admissions in a mixed Norwegian intensive care population.

BACKGROUND: Alcohol and drug abuse are potentially modifiable risk factors for critical illness. The aims of this study were to describe patients with substance abuse-related admissions (abbreviated SARA) in a mixed intensive care (ICU) population in Oslo, and to compare these patients with patients with non-SARA. METHODS: Cross-sectional prospective study of a mixed medical and surgical ICU-population in Oslo, Norway. Data were collected consecutively using a questionnaire, medical records, and toxicology results. SARA included admissions due to acute or chronic complications of alcohol or drug abuse, as well as substance abuse-related injuries. RESULTS: Of the 852 patients included, 168 (20%) had SARA; 102 (12%) alcohol-related and 66 (8%) drug-related. Male patients aged 18-39 had the highest proportion of SARA (47/97, 49%). Among the trauma patients, 69/182 (38%) were influenced by alcohol and drugs at the time of injury. Patients with SARA were significantly younger (median age 48 vs 66), had lower Charlson comorbidity index (mean 1.4 vs 2.5) and shorter length of stay (median days 2.4 vs 4.9), than non-SARA patients. Hospital mortality was similar when adjusting for age (OR 0.8, P = .27, non-SARA as reference). CONCLUSION: Overall, one in five ICU admissions was associated with substance abuse. For male patients aged 18-39 this ratio was nearly half. More than one third of the trauma patients were influenced by alcohol or drugs at time of injury.