BEIJING (CHINA DAILY/ASIA NEWS NETWORK) - Covid-19 and related diseases may cause lasting health problems, with more than 70 per cent of patients who have recovered still showing at least one symptom after they are well, according to a study.

The study, which tracked 1,733 Covid-19 patients discharged from Wuhan Jinyintan Hospital in Hubei province between Jan 7 and May 29, found that discharged Covid-19 patients are mainly troubled with fatigue, muscle weakness, sleep difficulties and anxiety.

The median follow-up time after which the patients started to show symptoms was six months, said Dr Cao Bin, the study's leading researcher and vice-president of the China-Japan Friendship Hospital.

The findings were released at the Lancet-CAMS (Chinese Academy of Medical Sciences) Health Conference that kicked off in Beijing on Nov 23.

The results showed that six months after patients first reported Covid-19 symptoms, about 50 per cent of them still had at least one symptom. More than 20 per cent reported psychological complications.

During hospitalisation, more severe patients tend to have more severely impaired lung diffusion capacity and abnormal chest imaging, Dr Cao said.

"It is necessary to conduct follow-up studies in recovered Covid-19 patients to better understand the consequences, prognosis, origin and development of the disease for early medical intervention," Dr Cao said.

"Such studies can also provide information for the development of vaccines and drugs, and we can be better prepared for potential outbreaks in the future," he added.

Previous research in China and other countries have indicated that discharged Covid-19 patients might have persistent symptoms such as impaired lung function and poorer quality of life, but the duration is much shorter - the longest follow-up time previously reported was about three months, Dr Cao said.

The research and tracking were conducted at the outpatient clinic of Wuhan Jinyintan Hospital, where trained physicians interviewed participants face to face, asking them to complete several questionnaires.

The research involved other tests such as a six-minute walk and blood test.

Based on the study, Covid-19 patients who have recovered still need to pay attention to their physical and mental well-being, even after they are discharged from hospitals, he said.

"It is recommended that recovered Covid-19 patients get regular exercise, avoid alcohol and smoking, get psychological counselling if necessary, and have a balanced diet," Dr Cao said.

"They should also continue taking medicines recommended by doctors while following hygiene and social distancing procedures."

Though the pandemic has been plaguing the world for almost a year, much about the virus is still unknown, including the health impact on recovered patients.

Research has been published in various journals such as Lancet and the Journal of the American Medical Association indicating that, like patients who recovered from Sars, some recovered Covid-19 patients are poised to face prolonged physical or psychological damage.

Prominent traditional Chinese medicine expert Zhang Boli said earlier that recovered Covid-19 patients, especially critically ill patients, are likely to have long-term health problems. They include damage to their immune system and organs such as their lungs, heart and kidneys that will require rehabilitation for proper recovery.

In general, however, most recovered patients will not suffer from lingering health consequences for too long and will recover soon, the academic from the Chinese Academy of Engineering added.

Meanwhile, a leading respiratory disease expert has warned that with the arrival of the flu season, more patients will be infected with both the influenza and the Covid-19 coronavirus in the near future.

"We need faster and more efficient testing technologies and facilities to detect the virus - the flu or Covid-19," said Dr Zhong Nanshan, a prominent respiratory disease expert, during a health science and technology innovation conference in Shenzhen, Guangdong province, last Friday (Nov 27).

There have already been reports of four cases infected with both the influenza A (H1 and H3) and the Covid-19 viruses, according to Dr Zhong.

"Wearing masks is still of great importance to fight against both the influenza A and the Covid-19 coronavirus," said Dr Zhong.