Immune system is capable of fighting virus

CHEST SCANS ON A 47-YEAR-OLD WOMAN IN AUSTRALIA WITH MILD DISEASE, SHOWED

THE PATIENT’S LUNGS CLEARING UP AFTER THE ANTIBODIES APPEARED IN THE BLOOD

NEW DELHI: A patient’s immune system can produce antibodies that fight mild-to-moderate cases of the novel coronavirus, according to a breakthrough study that experts say will be crucial in the development of a vaccine for the disease.

A 47-year-old woman in Melbourne, Australia, with mild-tomoderate coronavirus disease, or Covid-19, produced antibodies that fought the infection and recovered in about 10 days without any medicines, the study found.

The paper, published i n Nature Medicine journal on Tuesday by researchers at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, was based on blood samples tested at four different time points, which detailed how a patient’s immune system responds to the virus.

To be sure, the patient was otherwise healthy, the disease was of a mild- t o- moderate nature, and she was a nonsmoker. She was administered intravenous fluids to prevent dehydration, but not given any antibiotics, steroids or antiviral agents to treat the infection that primarily affected her lungs. She had travelled from Wuhan in China, the epicentre of the global epidemic.

“We showed that even though Covid-19 is caused by a new virus, in an otherwise healthy p e r s o n, a r o b us t i mmune response across different cell types was associated with clinical recovery, similar to what we see in influenza,” Professor Katherine Kedzierska of the Doherty Institute and one of the authors of the paper said.

“This is an incredible step forward in understanding what drives recovery of Covid-19. People can use our methods to understand the i mmune responses in larger Covid-19 cohorts, and also understand what’s lacking in those who have fatal outcomes.”

The study found the presence of four kinds of immune cells when the patient was sick that spurred the production of two kinds of antibodies. She was discharged to home isolation on day 10 of contracting the disease, and her symptoms disappeared completely on day 13. The antibodies remained in her blood from day 7 to day 20.

Chest s c ans s howed t he patient’s lungs clearing up after the antibodies appeared in the blood. The researchers are now working on whether the immune response will be sufficient to guard her against a future infection, Bloomberg reported.

The findings will be crucial in developing a vaccine for the coronavirus infection, which is still in its early stages of development, said experts.

Dr Irani Thevarajan, the first author of the paper, told the University of Melbourne that current estimates show more than 80% of Covid-19 cases are mildto-moderate, and understanding the immune response in these mild case is key to development of a vaccine.