By Nancy Lapid
(Reuters) – The following is a roundup of some of the latest scientific studies on the new coronavirus and efforts to find treatments and vaccines for COVID-19, the disease caused by the virus.
Possible “missing link” found in virus reproduction cycle
Researchers may have found a missing link in the reproductive cycle of coronavirus that could potentially be targeted by drugs, according to a report in Science on Thursday. Scientists already knew that once the virus breaks into a cell, it forms double-membrane sacs, like vesicles, in which it makes copies of its genetic material. But the socks appeared to be close and it was rather unclear how the genetic material of the sack moved into the fluid in the cell, where new virus particles assembled themselves. Eric Snijder of Leiden University Medical Center and his colleagues discovered small channels through both membranes that are wide enough to allow the genetic material to pass through. “In images with an electron microscope we can see ‘stuff’ sticking out of these channels. Probably this ‘stuff’ is the viral RNA on its way out, but once the sample is frozen there is no movement and must we still find ways to properly identify the ‘game’ as viral RNA, “Snijder told Reuters. “Blocking this channel in one way or another … could create a big problem for the virus to do its tricks,” he added. (https://bit.ly/2Xy4UZN)
Data suggest security, benefit of non-COVID faxes
Two new studies found that people who received vaccines for other viruses developed less or less serious coronavirus infections, although more research is needed to determine their potential efficacy against COVID-19. According to a study published in Cell Reports Medicine on Wednesday, people who have received the BCG tuberculosis vaccine in the last 3 years have not developed more severe coronavirus infections. “Results from the current BCG research are needed before definitive conclusions can be drawn,” said coauthor Mihai Netea of Radboud University Medical Center. A separate study by the Mayo Clinic, published online prior to peer review, found that people who received other vaccines in the past 5 years – such as flu, pneumonia, or hepatitis – had lower rates of coronavirus infection. Netea said the Mayo Clinic report suggests that the “beneficial effects of vaccines may be broader than currently known” and that his team had seen similar data on flu vaccines. (https://bit.ly/3fDzwPu; https://bit.ly/2DDlQXD)
Graph: Faxes and treatments in development https://graphics.reuters.com/HEALTH-CORONAVIRUS/yxmvjqywprz/index.html
Viral loads are high in asymptomatic patients
Asymptomatic COVID-19 patients may carry high loads of the new coronavirus in their nose, throat and lungs, and the loads tend to decrease more slowly than in patients who show symptoms, according to a report in JAMA Internal Medicine on Thursday. The researchers studied 303 young and otherwise healthy patients isolated in a community center for treatment in the Republic of Korea. Roughly a third had no symptoms when they were diagnosed, and about 20% of this group developed symptoms while isolated. Multiple tests over the course of about a month showed similar viral loads in people with or without symptoms. The tests could not distinguish active, if infected, virus particles from inactive particles. “For a better understanding of the viral contamination and potential transmissibility of asymptomatic infection, large rigorous epidemiological and experimental studies are needed,” the researchers wrote. (https://bit.ly/30zjthC)
Figures for U.S. cancer detection fell during pandemic
The average number of weekly diagnoses of six common types of cancer in the United States fell by 46% in the early stages of the pandemic, according to new data in JAMA Network Open. Researchers led by Dr. Harvey Kaufman of Quest Diagnostics studied more than 278,000 patients with new diagnoses of breast, colorectal, lung, pancreatic, gastric or esophageal cancer from early January to mid-April. In January and February, an average of 4,310 new cancers were diagnosed during the week, they reported. After March 1, weekly diagnoses fell between 25% and 52%. “Some cancers grow very slowly, but others grow a little faster and these delays can be significant for some patients,” Kaufman said. The American Society of Clinical Oncology (ASCO) has recommended cancer screening that requires visits postponed during the pandemic. But this is not a blank statement, ASCO’s chief medical officer, Dr. Richard L. Schilsky, told Reuters. “These are decisions that need to be weighed between the doctor and the patient,” he said, adding that they need to consider the patient’s cancer risk, as well as the chance of exposure to COVID-19. (https://bit.ly/3ibcIZb)
(Report by Nancy Lapid and Anne Harding; Edited by Tiffany Wu)
