Contagious SARS-CoV-2 isolated from air in hospital patients' room
Live SARS-CoV-2, the virus that causes COVID-19, was isolated from air samples collected 2 to 4.8 meters (6.6 to 15.7 feet) away from two coronavirus patients—one recently released and one newly admitted—in a single hospital room, according to a study published yesterday in the International Journal of Infectious Diseases.
Aiming to add to the discussion about whether aerosols can contain infectious coronavirus, University of Florida at Gainesville researchers used new air samplers with a gentle collection process that is less likely than commonly used samplers to inactivate viruses. They were able to detect SARS-CoV-2 only when using the samplers without a high-efficiency particulate air (HEPA) filter on the inlet tube.
The researchers collected three 3-hour air samples from a room on a dedicated COVID-19 ward that was well ventilated, with six air exchanges per hour and triple-filter treatment of air returned to the room. They isolated the coronavirus from the air samples on cell culture and sequenced the genome.
The genome sequence of the isolated virus matched that of the newly admitted patient, who had not undergone any aerosol-generating procedures. The other patient had been transferred to a long-term care facility the night before the air samples were collected.
The authors said their findings show that, even in the absence of aerosol-generating procedures, COVID-19 patients can produce aerosols that can spread the virus farther than the 6 feet recommended in physical distancing guidelines.
"For aerosol-based transmission, measures such as physical distancing by 6 feet would not be helpful in an indoor setting, provide a false-sense of security and lead to exposures and outbreaks," the researchers wrote. "With the current surges of cases, to help stem the COVID-19 pandemic, clear guidance on control measures against SARS-CoV-2 aerosols are needed, as recently voiced by other scientists."
Sep 15 Int J Infect Dis study
Surveillance, testing detect unnoticed COVID-19 cases at homeless shelters
Active surveillance and routine onsite testing could prevent the transmission of COVID-19 in homeless shelters, high-risk settings because of crowding, communal sleeping areas and shared bathrooms, University of Washington at Seattle researchers have found.
Their study, published yesterday in the Annals of Internal Medicine, involved testing 1,434 adult and pediatric residents and staff at 14 King County homeless shelters for COVID-19 infection from Jan 1 and Apr 24. This effort was part of a multiyear, cluster-randomized study of onsite testing and treatment for flu at homeless facilities started in November 2019.
Of the 1,434 people tested, 29 (2%) were positive for COVID-19 in five shelters. Most positive cases (21 [72.4%]) were identified during surge testing events rather than through routine surveillance, and 72.4% also had no symptoms. The 833 participants with symptoms were most likely to report a runny nose (43.0%), cough (37.3%), and muscle pain (23.7%).
Of the 725 people tested who had symptom-duration information, 40.3% had respiratory symptoms for less than 2 days at testing. Of all patients with positive test results, 31.2% met the case definition for influenza-like illness, while 12.7% met the criteria for coronavirus-like illness. Samples from 28 (2.1%) of participants tested positive for at least 2 of 17 tested respiratory pathogens, while 201 samples (15%) were positive for Streptococcus pneumoniae.
Those who tested positive for COVID-19 were more likely than those testing negative to be 60 years or older (44.8% vs 15.9%), and 86% of them slept in congregate spaces instead of private or smaller shared rooms.
Median participant age was 46 years (range, 0 to 82), and 67.9% of encounters in the shelters involved males, 40.9% involved whites and 30.5% involved blacks. Of all encounters, 57.7% involved smokers and 39.4% involved participants with one or more underlying medical conditions.
The authors said the findings indicate the need for routine COVID-19 testing outside of hospitals and clinics for the more than 560,000 homeless people in the United States. "Passive sentinel surveillance for respiratory viruses may only detect symptomatic cases severe enough to prompt health-seeking behavior and may miss milder ones, delaying the recognition of outbreaks and further viral spread," they wrote.
Sep 15 Ann Intern Med study
Children among latest DRC Ebola cases as outbreak grows to 123 cases
Two more Ebola cases were reported in the Democratic Republic of Congo (DRC) Equateur province outbreak, along with two more deaths, the World Health Organization (WHO) African regional office said today on Twitter. The developments lift the overall totals to 123 cases and 50 deaths.
The United Nations Office for the Coordination of Humanitarian Affairs (UN OCHA) said today in an update, posted on ReliefWeb, that a recent case was reported in a newly affected Ngelo Monzoi health area in the Bikoro health zone, raising the number of affected health areas to 40. It also said two infections in children were confirmed on Sep 14, one age 2 months and the other a 5-year-old.
WHO: Global testing still finding very few flu positives
Flu is still circulating at lower levels expected for this time of year in both hemispheres, likely influenced by steps to reduce COVID-19 measures, the WHO said in its latest regular update.
Though the Southern Hemisphere's season typically runs from April through September, the season still hasn't started, and in the Northern Hemisphere, flu is below interseasonal levels. Sporadic detections were reported in some tropical countries, and Cambodia reported some H3N2 activity.
Globally, of about 140,000 respiratory samples tested during the last half of August at WHO-affiliated labs, only 34 were positive for flu. Of those, 19 were influenza A and 15 were influenza B. Of the subtyped influenza A viruses, all were H3N2.
In other flu developments, the WHO committee that recommends the strains to include the Southern Hemisphere's 2021 flu season began their online deliberations today, which are scheduled to wrap up on October 2. The group will also assess flu viruses that have pandemic potential to see if any new candidate vaccine strains are needed.
Sep 14 WHO global flu update
WHO flu vaccine strain selection committee background information