Results from the first human challenge trial investigating COVID-19

By February 8, 2022November 3rd, 2022Covid-19 News

Individuals exposed to the original SARS-CoV-2 became infectious after just 2 days, which is earlier than scientists originally estimated, according to results from the first human challenge trial investigating COVID-19. In the study of 36 young and healthy subjects who were deliberately infected with SARS-CoV-2, viral shedding and symptoms began around 2 days post-inoculation, with viral load peaking at 5 days. The researchers published these findings, which have not yet been peer-reviewed, on the preprint server Research Square. Virus was first detected in the throat, but rose to significantly higher levels in the nose. The team did not observe a correlation between the level of viral load and symptoms. Additionally, the majority of infected participants reported mild-to-moderate cold-like symptoms that were limited to the upper respiratory tract, including stuffy or runny nose, sneezing, and sore throat. Loss of smell was also common.

An early release published in the CDC’s Morbidity and Mortality Weekly Report examining infection and hospitalization rates in Los Angeles County, California, depicts stark differences among vaccinated and unvaccinated individuals from November 7 to January 8, a period spanning the end of Delta variant predominance and the beginning of Omicron’s predominance. Data were further stratified among vaccinated individuals to include those with and without a booster to show booster effectiveness. For the 14-day period ending December 11, also the last week of Delta predominance, incidence and hospitalization rates among unvaccinated individuals were 12.3 and 83.0 times, respectively, those of boosted fully vaccinated individuals, and 3.8 and 12.9 times, respectively, those of fully vaccinated individuals without a booster. During the period ending January 8, when Omicron gained predominance, the rate ratios dropped, but vaccinated persons remained better protected. Unvaccinated individuals had infection and hospitalization rates 3.6 and 23.0 times, respectively, those of fully vaccinated persons with a booster and 2.0 and 5.3 times, respectively, those of fully vaccinated persons without a booster. According to Los Angeles County Department of Public Health data, 71% of county residents were fully vaccinated as of January 8. During a White House briefing on February 2, US CDC Director Dr. Rochelle Walensky shared data from 25 US jurisdictions showing unvaccinated individuals were 14 times more likely to die of COVID-19 than fully vaccinated individuals and unvaccinated individuals were 97 times more likely to die than people who were fully vaccinated and boosted. According to an analysis of Omicron’s impact conducted by the Financial Times, nearly half of US COVID-19-related hospitalizations this winter could have been prevented if the nation had vaccination coverage similar to leading European countries. About 64% of the total US population is fully vaccinated, and only 42% of eligible individuals have received a booster dose.

The COVID-19 pandemic response has generated tens of thousands of metric tons of extra medical waste, straining healthcare waste management systems, threatening human health and the environment, and highlighting an urgent need to improve waste management protocols, according to a WHO reportreleased this week. Overall, the WHO estimates the pandemic has increased healthcare waste loads up to 10 times, potentially exposing workers to needle-stick injuries, burns, and infections, and local communities to poorly managed landfills and carcinogens from improperly incinerated waste. The report encourages countries to see this as an opportunity to revamp waste streams, recommending healthcare facilities and the public responsibly use and dispose of waste and calling for investment into innovative waste treatment technologies and the use of more reusable, recyclable, or biodegradable materials.

Last week CSSE is reporting 76,165,124 positive cases in the U.S. and 899,895 deaths.