Doctors at Delhi’s All India Institute of Medical Sciences have said that patients who have recovered from the coronavirus are at risk of developing pulmonary fibrosis, or scarring of the lungs that causes fatigue and shortness of breath, Hindustan Times reported on Thursday.

Two recovered patients have been recommended lung transplants, a month after it was first performed on a coronavirus positive person in Chennai. Dr Randeep Guleria, AIIMS director and pulmonologist, said data shows that around 60%-80% of recovered patients may have a condition caused by another disease. “It can be mild in the form of fatigue and body aches,” he told the newspaper. “But it can also be very serious in the form of individuals requiring to be on long-term oxygen therapy. We have had two individuals who have had extensive lung fibrosis and are being advised lung transplants. And we have people who have significant cardiac abnormalities and stroke.”

While most patients fully recover from the infection, some experience persistent symptoms of breathlessness, fatigue, erratic heartbeat, gastrointestinal problems, muscle and joint pains. A few patients are also likely to develop irreversible cardiovascular and respiratory damage.

Guleria also warned about psychiatric disorders, not just a cause of the coronavirus, but also because of the physical isolation due to the health crisis.

Dr Anant Mohan, head of the pulmonary medicine department in AIIMS, said doctors were likely to see several patients with prevalence of lung fibrosis. “There is no estimate of prevalence of post-Covid-19 fibrosis but given the volume of Covid-19 cases, even if it is a small percentage, the absolute numbers are likely to be huge,” he added. “Lung transplant is an option for a very select group of people – those with extensive fibrosis and acute respiratory distress but who do not have other co-morbidities like renal dysfunction and muscle wasting after Covid-19.”

Last month, experts had said that the coronavirus can affect not only the lungs but almost all parts of the body as it is a “multi-systemic disease”.

Coronavirus capable of invading brain: US study

Meanwhile, a United States study published on Wednesday said that headaches, confusion and delirium experienced by some patients could be the result of the virus directly invading the brain, AFP reported. The preliminary research, led by Yale immunologist Akiko Iwasaki, stated the coronavirus is able to replicate inside the brain and starves nearby cells of oxygen.

“Understanding whether or not there is direct viral involvement of the brain is extraordinarily important,” said S Andrew Josephson, chair of the neurology department at the University of California, San Francisco. He also lauded the techniques used in the study, but said he would remain cautious until the paper underwent peer review.

Globally, the coronavirus has infected more than 2.77 crore people and claimed 9,01,050 lives, according to Johns Hopkins University. Over 1.86 crore people have recovered from the infection worldwide.