The most troubling is that the virus may be leaving some people with permanent lung damage, as is apparent by doctors reporting that an increasing number of “recovered” patients are still experiencing breathlessness and coughing months after falling ill who have chest scans that show evidence of irreversible lung scarring.
The true numbers of people that have been affected aren’t known yet, but estimates are high as 1 in 5 of those who needed intensive care have some form of scarring. Permanent damage such as this is also sometimes seen after experiencing other kinds of chest infections that cause similar lung inflammation such as pneumonia and the flu.
“We have always seen this before – what’s different is the scale of this,” says James Chalmers, a chest physician and adviser to the British Lung Foundation. Previously, his clinic in Scotland would have seen post-infection scarring of the lungs just once or twice a year, he says. “Now we are seeing dozens of patients coming through.”
In Italy doctors are scanning the lungs of those who were infected 3 months after they fell ill; although this study is still ongoing preliminary results estimate that 15-20% of those who were treated in intensive care for COVID-19 have scarring to some degree, according to Paolo Spagnolo at the University Hospital of Padua who says, “We have to be prepared in the future to manage these patients.”
In the majority of people this virus only causes mild symptoms with varying symptoms, but in some the virus can lead to serious lung inflammation and an excess of immune signalling chemicals that trigger a cytokines storm.
“If left unchecked, the inflammation starts to cause damage and scarring,” says Chris Meadows, an intensive care doctor at Guy’s and St Thomas’ NHS Foundation Trust in London.
This scarring is called fibrosis, and unfortunately at this time there is no known way to reverse it; all that one can do is to try and improve their aerobic fitness to attempt to compensate for their lower lung functions while learning how to cope with breathlessness.
Scarring is not the only troubling issue as there may be other mechanisms that are causing long term complications such as severe infection making the blood more prone to clotting causing patients to develop tiny clots in the blood vessels of their lungs. New blood vessels are generated to try and compensate, but these can be disorganised and lead to high blood pressure in the lungs. “You don’t get as much oxygen,” says Chalmers.
What’s more is that lung damage has not been confined to those who needed ventilation, according to Chalmers who says, “More severe covid means more likelihood of permanent damage, but I have got a couple of patients who were not on ventilators and have long-term complications.”
To end on a positive note, dexamethasone has become the first drug to show a lower death rate in the seriously ill by tamping down the overactive immune system. A preliminary study has found that the cheap and widely available steroid reduces the risk of dying from serious infection with COVID-19 by one third in those requiring ventilation and one fifth for those requiring oxygen. Perhaps if seriously ill patients are given this drug sooner, it may help to avoid at least some of the scarring as well?
