No observed benefit from plasma treatment in severe COVID-19; the virus can affect male fertility

(Reuters) – The following is a summary of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the disease caused by the virus.

Plasma treatment shows no benefit in severe COVID-19

Blood plasma from COVID-19 survivors was of little benefit to patients with severe COVID-19 pneumonia, Argentine researchers reported in the New England Journal of Medicine on Tuesday. The so-called convalescent plasma, which delivers antibodies from COVID-19 survivors to infected people, has not improved the health of critically ill patients or reduced their risk of dying from the disease better than a placebo. Researchers randomly assigned 333 hospitalized patients with severe COVID-19 pneumonia to receive convalescent plasma or a placebo. After 30 days, they found no significant difference in the symptoms or the health of the patients. The mortality rates were roughly the same: 11% in the convalescent plasma group and 11.4% in the placebo group, a difference not considered statistically significant. There is still a possibility that convalescent plasma could help less ill patients who receive treatment earlier in their illness, said study leader Dr Ventura Simonovich of Hospital Italiano in Buenos Aires. A separate randomized trial in Argentina, posted on medRxiv on Saturday ahead of the peer review, found that when elderly COVID-19 patients were given convalescent plasma within 72 hours of the onset of their symptoms instead of a placebo, they were much less likely to become seriously ill. (bit.ly/3pRZ8i2; bit.ly/3l4Xeac; reut.rs/3fFPJ8D)

COVID-19 can harm male fertility

Evidence of testicular damage from COVID-19 has accumulated in a series of small autopsy studies, suggesting that the new coronavirus may have an impact on male fertility. Researchers at the University of Miami in Florida compared testicular tissue from six men who died from COVID-19 and three who died from other causes. Three of the COVID-19 patients had testicular lesions that would affect their ability to produce sperm. A Chinese research team made similar observations earlier this year and also found that the immune systems of some patients with COVID-19 “attack” the testes, causing severe inflammation or orchitis. A separate Chinese team has found “significant damage” to the basic cell tissue of the testes in 12 men who died from COVID-19. “The possibility that COVID-19 damages the testes and affects fertility … warrants an assessment of gonadal function in men infected with COVID-19, or who have recovered from COVID-19 and desire fertility,” the Miami team concluded in a published report. in the World Journal of Men’s Health. (bit.ly/39eDMFH; bit.ly/3q1Iyws; bit.ly/3714Fdq)

Mutations don’t appear to help coronavirus spread faster

The new coronavirus detects genetic changes as it spreads around the world, but currently documented mutations do not appear to be helping it spread any faster, scientists said in the journal Nature Communications on Wednesday. Using a global dataset of the virus genomes of 46,723 people with COVID-19 from 99 countries, the researchers identified more than 12,700 mutations in the genetic material of the virus. Of those, the scientists focused on 185 mutations that they said had occurred at least three times independently during the pandemic. “Fortunately, we have found that none of these mutations allow for the faster spread of COVID-19,” said co-author Lucy van Dorp of the Genetics Institute at University College London. Other experts, however, have suggested that a mutation, known as D614G, increases the transmissibility of the virus. François Balloux, a UCL professor who worked on the study, said his findings, so far, do not threaten the effectiveness of the COVID-19 vaccine. “The virus may well acquire vaccine leakage mutations in the future, but we are confident that we will be able to report them quickly, which would allow vaccines to be updated in time if necessary,” he said. he declares. (go.nature.com/2JgkNQ0; reut.rs/3pZFtgj)

Most Americans still lack COVID-19 antibodies

As of September, the vast majority of U.S. residents still had not been exposed to the novel coronavirus, antibody test results suggest. In all 50 states, the District of Columbia and Puerto Rico, researchers looked for COVID-19 antibodies in nearly 178,000 blood samples taken between July and September from patients being tested for reasons unrelated to the coronavirus. In all but a few states, antibody levels suggested less than 10% of the population had either been infected or recovered from COVID-19. The highest prevalence of COVID-19 antibodies was in New York City – the early epicenter of the outbreak in the United States – where about 25% of blood samples were positive in mid-August. In some states, the proportion of people with COVID-19 antibodies appeared to be less than 1%. So-called seroprevalence rates tended to decline over time, the researchers found, although they had increased in some states, including Georgia and Minnesota. In a report published Tuesday in JAMA Internal Medicine, researchers said more work is needed to find out if and how the presence of antibodies affects people’s vulnerability to re-infection with COVID-19. (bit.ly/3m50HqM; bit.ly/2Jd67kG)

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