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.

SARS-CoV-2 in the Air Surrounding Patients during Nebulizer Therapy.

Nebulizer therapy is commonly used for patients with obstructive pulmonary disease or acute pulmonary infections with signs of obstruction. It is considered a "potential aerosol-generating procedure," and the risk of disease transmission to health care workers is uncertain. The aim of this pilot study was to assess whether nebulizer therapy in hospitalized COVID-19 patients is associated with increased dispersion of SARS-CoV-2. Air samples collected prior to and during nebulizer therapy were analyzed by RT-PCR and cell culture. Total aerosol particle concentrations were also quantified. Of 13 patients, seven had quantifiable virus in oropharynx samples, and only two had RT-PCR positive air samples. For both these patients, air samples collected during nebulizer therapy had higher SARS-CoV-2 RNA concentrations compared to control air samples. Also, for particle sizes 0.3-5 µm, particle concentrations were significantly higher during nebulizer therapy than in controls. We were unable to cultivate virus from any of the RT-PCR positive air samples, and it is therefore unknown if the detected virus were replication-competent; however, the significant increase in smaller particles, which can remain airborne for extended periods of time, and increased viral RNA concentrations during treatment may indicate that nebulizer therapy is associated with increased risk of SARS-CoV-2 transmission.

Antibodies to common infectious agents in coronary artery disease patients with and without rheumatic conditions.

OBJECTIVES: The mechanism linking inflammation to atherosclerosis is unknown. We have previously demonstrated a high occurrence of inflammation in the aortic adventitia of patients with coronary artery disease (CAD), which was more pronounced in patients with inflammatory rheumatic diseases (IRDs), and which might be involved in the pathogenesis of cardiovascular disease. In theory, infections might play a role in the pathogenesis of vascular inflammation or atherosclerosis, or both. This study compared seropositivity and the burden of several common infections in patients with CAD, both with and without IRD, and in healthy controls (HCs). Moreover, we looked for relationships between the examined antibodies and inflammatory infiltrates in the aortic adventitia. METHODS: We examined sera for Chlamydophila pneumoniae, Mycoplasma pneumoniae, Helicobacter pylori, CMV, Streptococcus pyogenes, parvovirus B19, HBV and HCV with commercially available serological tests in 67 patients with IRD, 52 patients without IRD and 30 HCs. RESULTS: We observed neither any statistically significant differences in the examined antibodies between the groups nor a difference in the burden of infection. Except for a protective effect of mycoplasma immunoglobulin A (IgA), we did not find any other associations between the examined antibodies and the occurrence of aortic adventitial mononuclear cell infiltrates. CONCLUSION: Our study does not support the notion that chronic infections or infectious burden contribute to accelerated occurrence of CAD in IRD. Mycoplasma IgA was related to a lower occurrence of aortic adventitial inflammation.

A multidrug-resistant, methicillin-susceptible strain of Staphylococcus aureus from a neonatal intensive care unit in Oslo, Norway.

Over a 6-month period in 2008, approximately 15% of all Staphylococcus aureus isolates from our neonatal intensive care unit were resistant to penicillin, gentamicin, erythromycin and clindamycin. Extended antibiotic susceptibility testing and molecular profiling revealed an outbreak of an S. aureus strain with a rare susceptibility pattern for a Scandinavian setting.