U.S. researchers say an experimental coronavirus vaccine has shown promising immune responses in an on-going early-stage study.
The potential new vaccine was manufactured by U.S.-based biotech firm Moderna and developed by researchers at the National Institute of Allergy and Infectious Diseases. In a report published in the New England Journal of Medicine Tuesday, the researchers gave two doses of the experimental vaccine to 45 volunteers, whose ages ranged between 18 and 55.
The researchers said none of the volunteers experienced a serious side effect, but more than half reported mild or moderate reactions such as fatigue, headaches, chills, muscle aches and pain at the injection site.
The results of the vaccine, the first to be tested in humans, was part of the first phase of a trial designed to test low, medium and high doses of the vaccine to gauge both its safety and its ability to create immunity.
“It’s a first step, but it is an exciting first step," said Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Nashville, Tennessee, who was not involved in the study.
Moderna is currently in the second testing phase of the vaccine, which will involve a larger group of volunteers to determine its effectiveness. The company will launch a third testing phase on July 27, which will involve 30,000 volunteers, the largest study of a potential COVID-19 vaccine so far.
Another biotech firm, Johnson & Johnson, is also expected to begin late-stage human trials for a potential vaccine by the end of July.
Meanwhile, doctors in France are reporting what is believed to be the first case that COVID-19 can be transmitted from a pregnant mother to a baby in the womb.
A report in the science journal Nature Communications says a 23-year-old woman in the late stages of pregnancy tested positive for COVID-19 after she was admitted to a Paris hospital with a fever and severe cough. Her child was delivered via emergency caesarean section three days later after showing signs of distress.
Tests on the baby’s blood and fluid from his lungs after he became irritable, had trouble feeding and began experiencing muscle spasms came up positive for coronavirus infection. Further tests showed the virus had spread from the mother’s blood into the placenta, where it replicated and passed on to the baby.
Dr. Daniele De Luca, the director of pediatrics and neonatal critical care at South Paris University, and the lead researcher of the study, says the baby recovered without specific treatment and is “clinically” normal. The mother has also recovered.