(Reuters) - The following is a brief roundup of some 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.
Tuberculosis vaccine may limit COVID-19 deaths
A tuberculosis vaccine routinely given to children in countries with high rates of that bacterial disease might be helping to reduce deaths from COVID-19, researchers reported on Thursday in the scientific journal Proceedings of the National Academy of Sciences. After accounting for differences in factors that might affect vulnerability to the virus - such as income, education, health services and age distribution - the researchers found that countries with higher rates of Bacille Calmette-Guérin (BCG) vaccinations for tuberculosis had lower peak mortality rates from COVID-19. A good example was Germany, which had different vaccine plans before East Germany and West Germany were unified in 1990, the researchers said. COVID-19 mortality rates among senior citizens are nearly three times higher in western Germany than in eastern Germany, where more older people received the vaccine as infants, they found. Study co-author Luis Escobar of Virginia Tech said in a press statement that BCG vaccines have been shown to protect against other viral respiratory illnesses. Escobar cautioned that the new findings are preliminary. The BCG vaccine is currently being tested for preventing COVID-19 in healthcare workers. (bit.ly/3gMvFkh)
Weekly dorm screenings would not contain COVID-19 outbreaks
Avoiding coronavirus outbreaks in college dormitories would require screening tests for residents at least every three days, according to Yale University researchers. Weekly screening would not be sufficient, they concluded. Their calculations, based on a computer model of 5,000 students and an 80-day semester, accounted for students' on-campus exposures to the virus as well as imported infections from students travelling, wandering about town to restaurants and bars, or from visitors. Frequent testing would interrupt transmission of the virus only if infected students are isolated, the researchers said. "Students must comply with infection control, social distancing, test scheduling and (if testing positive) isolation requirements for the repeat testing system to work effectively," the researchers said in a paper posted online on Thursday ahead of peer review. Also, the tests must be reliable, testing laboratories must guarantee timely results, and efficient communications and supports must be in place so students who test positive can be isolated quickly, they said. The researchers said universities must be prepared to close their residence halls if repeated testing fails to contain the spread of the pathogen on campus. (bit.ly/2CmjrQA)
Molecular study finds multiple types of COVID-19
There are many "flavours" of COVID-19, according to new data that may someday allow coronavirus treatments to be targeted at the specific molecular changes making a person sick. To learn more about why only some coronavirus patients become severely ill, researchers studied patients' "blood transcriptome," the complete set of genes that are activated in immune cells in the blood. They found at least five different types of immune response against the coronavirus - not just "mild" and "severe," according to a paper posted online ahead of peer review. "In other words, there are different flavours of the disease," just as there are different types of cancer, study co-author Dr. Joachim Schultze of the University of Bonn told Reuters. Understanding the molecular mechanisms at work in a given patient could help doctors tailor the therapy to target those mechanisms, Schultze said. The findings also helped his team predict which drugs would likely benefit COVID-19 patients. One "prominent" candidate cited was the steroid dexamethasone, which has already been proven effective in some COVID-19 patients. Another "surprising" discovery they cited involved granulocytes, a type of white blood cell. "Granulocytes, cells that are not really known to be major players in the fight against viruses, play a major role in severe COVID-19 disease," Schultze said. The new findings "will help us to find better therapies and also will guide vaccine development," he added. (bit.ly/38GXUhA)
Months later, recovering patients still have symptoms
More evidence is emerging that severe COVID-19 has lingering after-effects. Nearly 90% of recovering COVID-19 patients discharged from a hospital in Rome were still not back to normal an average of two months after becoming ill, researchers said. Doctors there studied 143 adults who had been hospitalized on average for two weeks. Most had been diagnosed with pneumonia, and one in five had needed help to breathe. An average of 60 days after their first coronavirus symptoms, 87.4% still reported at least one symptom - particularly fatigue and shortness of breath - and 55% had three or more, researchers reported on Thursday in the Journal of the American Medical Association. About one in four still had joint pain, and about one in five had chest pain. Roughly 44% said their quality of life was worse now than before they got sick. The researchers did not have information on patients' pre-COVID-19 medical problems and did not compare this relatively small group to patients discharged for other reasons. But they said their findings suggest more research is needed on the long-lasting effects of coronavirus infection. (bit.ly/2ZfFcdz)
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Reporting by Nancy Lapid; Editing by Will Dunham
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