IMMUNITY

Why are some Covid-19 survivors at risk of blood clot

Nanyang Technological University in Singapore finds recovered patients have twice the normal number of circulating endothelial cells (CECs)

Why are some Covid-19 survivors at risk of blood clot

Recovered Covid-19 patients had twice the normal number of circulating endothelial cells (CECs) that had been shed from damaged blood vessel walls. (Photo: Thinkstock)

Singapore, April 14

People who have recovered from Covid-19, especially those with pre-existing cardiovascular conditions, may be at risk of developing blood clots due to a lingering and overactive immune response, according to a study.

The study, led by researchers from Nanyang Technological University in Singapore, found has that recovered Covid-19 patients had twice the normal number of circulating endothelial cells (CECs) that had been shed from damaged blood vessel walls.

The elevated levels of CECs indicate that blood vessel injury is still apparent after recovering from viral infection.

The recovered Covid-19 patients also continued to produce high levels of cytokines -- proteins produced by immune cells that activate the immune response against pathogens -- even in the absence of the virus.

Unusually high numbers of immune cells, known as T cells, that attack and destroy viruses were also present in the blood of recovered Covid-19 patients.

The presence of both cytokines and higher levels of immune cells suggest that the immune systems of recovered Covid-19 patients remained activated even once the virus was gone, revealed the findings published in the peer-reviewed scientific journal eLife.


Experts: New Covid strain more dangerous for youth


The researchers hypothesise that these persistently activated immune responses may attack the blood vessels of recovered Covid-19 patients, causing even more damage and increasing the risk of blood clot formation further.

"While Covid-19 is mainly a respiratory infection, the virus may also attack the linings of blood vessels, causing inflammation and damage. Leakage from these damaged vessels triggers the formation of blood clots that may result in the sort of complications seen in the patients during hospitalisation," said Florence Chioh, research assistant at NTU's Lee Kong Chian School of Medicine.

The study "makes a strong case for the close monitoring of recovered Covid-19 patients, especially those with pre-existing cardiovascular conditions like hypertension and diabetes who have weakened blood vessels," said Christine Cheung, Assistant Professor at NTU's Lee Kong Chian School of Medicine.

The team collected and analysed blood samples from 30 Covid-19 patients a month after they had recovered from the infection and were discharged from hospital.

--IANS

Top Stories

Can't give Rs 4 lakh compensation to Covid victims, Centre tells SC

Can't give Rs 4 lakh compensation to Covid victims, Centre tells SC

Says finances of states, Centre under strain due to reductio...

Delhi Unlock: Public parks, gardens to open from Monday; outdoor yoga activities to be allowed

Delhi Unlock: Public parks, gardens to open from Monday; outdoor yoga activities to be allowed

Prohibited activities and services, including cinemas, gyms,...

Ahead of J-K outreach, PM Modi holds high-level ministerial meeting

Ahead of J-K outreach, PM Modi holds high-level ministerial meeting

PAGD to meet on June 22 to decide on Centre's invitation; PD...

Haryana lockdown curbs relaxed; bars, restaurants to open till 10 pm

Haryana lockdown curbs relaxed; bars, restaurants to open till 10 pm

Lockdown extended till June 28 for the seventh time

Five defence officers set to face General Court Martial in DeMo scam

Five defence officers set to face General Court Martial in DeMo scam

Accused of exchanging Rs 6 lakh invalid currency

Cities

View All