Phylogenetic analysis of SARS-CoV-2 in the Boston area highlights the role of recurrent importation and superspreading events. These trees can inform the epidemiology of spread of infection, including detection of related strains of virus and identification of unrecognized routes of infection. Sequencing of virus isolated from infected persons enables the construction of phylogenetic trees that show how viruses are genetically related to one another. While hand hygiene is critical in preventing fecal-oral (via contact with respiratory mucosa) transmission, improving bathroom ventilation and periodically running faucets to ensure U-trap water seals are not dried out, particularly in high-rise buildings, might also help prevent transmission. adds to growing evidence that wastewater plumbing systems might be reservoirs for SARS-CoV-2 and other pathogens. An editorial external icon notes that Kang et al. and Kang et al.): Some COVID-19 patients shed SARS-CoV-2 RNA in stool for weeks after symptom onset and replication-competent virus has been demonstrated in a minority fomites or inhalation of bioaerosols containing virus might play roles in SARS-CoV-2 transmission. Implications for both studies (van Doorn et al. Available via American College of Physicians Public Health Emergency Collection through PubMed Central. After toilet flushing, aerosols pass through U-trap with dried out water seals under floor and bathtub drains (but not through U-traps with water), and gas plumes containing bioaerosols may escape into master bathrooms of vertically aligned apartments. Suggested flow for sewage (thick arrows) and aerosols (thin arrows) through the drainage system. Limitations: Disinfection in family BвЂ™s and family CвЂ™s apartments prior to sampling prevented assessment for SARS-CoV-2 sequencing was not performed on viral isolates from the cases to determine if viruses were genetically linked no information was given whether family A members expectorated sputum into the drains. Methods: Contact tracing and throat swabs for SARS-CoV-2 by RT-PCR for all other 193 residents and 24 staff in the building, 237 surface and air samples from 11 apartments and common areas were tested for SARS-CoV-2 by RT-PCR, common elevator use assessed by closed-circuit television review, and tracer gas released into bathrooms to simulate virus-laden aerosols.

Families B and C reported not using their bathtubs, suggesting dried out U-trap water seals.

Tracer gas released in family AвЂ™s bathroom was detected in vertically aligned bathrooms.

Samples from other building areas including the apartments where families B and C lived were negative.

Environmental samples from family AвЂ™s bathroom and bedroom (n = 5), and from the bathroom in the unoccupied apartment one floor above (n = 1) were positive for SARS-CoV-2.

All other 193 residents and 24 staff in the same building tested negative for SARS CoV-2.

The families did not have direct contact with each other, including in common elevators.

Family A had traveled to Wuhan families B and C had no travel history and later symptom onset.

All 9 members of 3 families (A, B, and C) living in vertically aligned apartments connected by master bathroom drainage pipes were diagnosed with COVID-19 between January 26 and Febru(Figure).

Annals of Internal Medicine (September 1, 2020). Probable evidence of fecal aerosol transmission of SARS-CoV-2 in a high-rise building external icon. Limitations: Significant heterogeneity in included studies few studies investigated viability of virus in fecal samples.Д«. A weighted pooled estimate of the proportion testing positive was calculated for studies with at least 10 patients. Viability was assessed by isolating live SARS CoV-2 in cultured specimens. Methods: Systematic literature search identifying studies published in English, Dutch, or German from December 2019 to July 7, 2020, of COVID-19 patients who had stool samples or anal swabs tested for SARS-CoV-2 by RT-PCR.

The presence of replication-competent SARS-CoV-2 was investigated in 5 studies and found to be present in 6/17 (35%) patients.

Across 42 studies reporting duration of SARS-CoV-2 in gastrointestinal specimens, patients tested positive for a mean of 25.0 (range 3-70) days after symptom onset.

Across 91 studies, a weighted pooled 51.8% (95% CI 43.8%-59.7%) of stool samples or anal swabs from COVID-19 patients were positive for SARS-CoV-2.Alimentary Pharmacology and Therapeutics (August 27, 2020). Systematic review with metaвЂђanalysis: SARSвЂђCoVвЂђ2 stool testing and the potential for faecalвЂђoral transmission external icon. Below we summarize a systematic review and an epidemiologic and environmental investigation exploring the possibility of transmission from fecal sources.ДЄ. Some patients with COVID-19 have gastrointestinal symptoms including diarrhea, vomiting, and abdominal pain, and SARS-CoV-2 has been found in patientsвЂ™ stool.

Infection detected in on1 resize