Here is a brief weekly roundup of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.
Twin antibodies better than one?
Scientists have found twin antibodies that neutralize the new coronavirus, each by slightly different mechanisms. Finding a way to use both antibodies simultaneously might be a particularly good way to attack the virus, the researchers say. According to their report in Science on Wednesday, the two antibodies were isolated from a patient who recovered from COVID-19. Both work by attaching to a spike on the virus that helps it break into human cells. Because the antibodies each bind to different places on the spike, a "cocktail" containing both may be more effective than a treatment using either one by itself. The information could also help in the development of a preventive vaccine, the laboratory experiments suggest. Furthermore, even if the virus mutates so that one of the antibodies no longer works, the other might still retain its neutralizing activity.
Childhood cancer and COVID-19 risk
Children with cancer may be no more vulnerable to the coronavirus than healthy kids. Children with cancer do not need to delay treatment for fear of becoming more vulnerable to the new coronavirus, according to a study reported on Wednesday last week in JAMA Oncology. “It was reassuring that they didn’t appear to be any more vulnerable than other children,” Dr. Andrew Kung, coauthor of the study and head of pediatrics at Memorial Sloan Kettering Cancer Center in New York, told Reuters. “With this information, we can now feel confident to forge ahead with cancer therapy and not delay out of fears of affecting susceptibility to COVID-19.”
Among children with cancer but without symptoms of coronavirus infection, only 2.5% tested positive for the virus, researchers reported. Among those who had been exposed to the virus or had symptoms suggestive of infection, 29.3% tested positive, with only one requiring hospitalization. Altogether, the team tested 178 children and 74 adult caregivers for the virus. Among the children’s asymptomatic caregivers, 14.7% turned out to be infected. “Even in that setting, we found that just half of the time when a caregiver was positive did the kid also test positive,” Kung said. “This suggests that there is something about kids that makes them less susceptible not just to the development of symptoms but to the infection itself.”
A cheaper way to study genomes
Researchers have found a simpler, cheaper way to sequence the coronavirus genome, a crucial process that allows researchers to access the genetic information in the RNA of the virus. "This approach builds on ongoing sequencing efforts by other groups but bypasses time-consuming and costly steps in preparing samples for sequencing," Daryl Gohl of the University of Minnesota Genomics Center, who led the research, told Reuters. "The ability to sequence SARS-CoV-2 at low cost and at large scale will aid in the genomic surveillance of (the virus) for public health efforts, and has the potential to accelerate studies on the influence of viral genetics on transmissibility, virulence, and clinical outcomes." The paper describing the new method was posted online on Tuesday on the bioRxiv website but has not yet been peer-reviewed.
Can COVID-19 spread through feces?
The new coronavirus may not spread via contact with fecal matter, researchers suggest in a report on Wednesday in Science Immunology. In laboratory experiments, they discovered that while the virus does infect the cells of the small intestine, fluid from the large intestine inactivates it, so that the virus is no longer infectious by the time it is excreted in feces. The authors caution, however, that because they only studied fecal samples from 10 patients, they cannot definitively rule out the fecal-oral transmission of COVID-19. Their findings also suggest that certain protein-digesting enzymes help the new coronavirus enter cells in the gut. Blocking those two enzymes might be a way to treat the infection, they speculate, especially since a drug that inhibits the TMPRSS2 enzyme is already approved in Japan to treat pancreatitis.