Becker's Hospital Review

47 FINANCE CMO / CARE DELIVERY Nearly 60% of COVID-19 spread may come from asymptomatic spread, model finds By Gabrielle Masson P eople with COVID-19 who don't exhibit symptoms may transmit 59 percent of all virus cases, according to a model developed by CDC researchers and published Jan. 7 in JAMA Network Open. Since many factors influence COVID-19 spread, researchers developed a mathematical approach to assess several scenarios, varying the infec- tious period and proportion of transmission for those who never dis- play symptoms according to published best estimates. In the baseline model, 59 percent of all transmission came from asymp- tomatic transmission. at includes 35 percent of new cases from peo- ple who infect others before they show symptoms and 24 percent from people who never develop symptoms at all. Under a broad range of val- ues for each of these assumptions, at least 50 percent of new COVID-19 infections were estimated to have originated from exposure to asymp- tomatic individuals. e more contagious variant first identified in the U.K. and since found in six states underscores the importance of the model findings, said Jay Butler, MD, CDC deputy director for infectious diseases and a co-author of the study. "Controlling the COVID-19 pandemic really is going to require con- trolling the silent pandemic of transmission from persons without symptoms," Dr. Butler told e Washington Post. "e community mit- igation tools that we have need to be utilized broadly to be able to slow the spread of SARS-CoV-2 from all infected persons, at least until we have those vaccines widely available." Whether vaccines stop transmission is still uncertain and was not a scenario addressed in the model. n COVID-19 'long haulers' identify 205 virus symptoms By Mackenzie Bean R esearchers have identified more than 200 long-term symptoms that can affect COVID-19 "long haulers," or people who experience prolonged effects from the vi- rus, according to a survey published Dec. 24 in the medical preprint server medRxiv. Researchers polled 3,762 adults from 56 countries with con- firmed or suspected COVID-19 cases. Respondents devel- oped symptoms before June 2020 and experienced them for a minimum of 28 days. Four survey findings: 1. In total, respondents identified 205 symptoms in 10 organs linked to the virus, including 66 symptoms traced over seven months. 2. The most commonly reported symptoms after six months were fatigue (77.7 percent), post-exertional malaise (72.2 per- cent) and cognitive dysfunction (55.4 percent). 3. Respondents who were sick six months after symptom on- set experienced an average of 13.8 symptoms. 4. Most respondents had not returned to full-time work due to their health issues. As of Jan. 4, the survey has not been peer-reviewed. n CDC: Severe allergic reactions from COVID-19 vaccines rare By Erica Carbajal A total of 21 anaphylaxis cases were reported among the first nearly 2 million Pfizer-BioN- Tech COVID-19 vaccine doses administered between Dec. 14-23, according to the CDC's Morbidity and Mortality Weekly Report published Jan. 6. Of the 21 cases that were determined to be anaphy- laxis, 17 had a history of allergic reactions or allergies, while seven had previously experienced anaphylaxis. The majority of cases occurred within the first 15 min- utes after vaccination. In 19 of those cases, epineph- rine was given as part of treatment. A total of four pa- tients were hospitalized, while 17 were treated in the emergency department. The CDC was able to follow up with 20 of the people who experienced the severe allergic reaction and found that all had recovered. "Based on early safety monitoring, anaphylaxis after Pfizer-BioNTech COVID-19 vaccine appears to be a rare event," the report said. However, the CDC advised vaccination locations to ensure they have supplies on hand to manage anaphylaxis, prescreen recipients to identify those who may be at risk and enact post-vacci- nation observation periods based on a patient's history, among other guidance. n

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