Concerns about "long-haul" symptoms in COVID-19 survivors may be reignited by a new study: It finds that 3 out of 4 patients from Wuhan, China -- where the pandemic originated -- were still suffering at least one lingering health problem six months later.
The study from China involved more than 1,700 patients first diagnosed with the virus in Wuhan between January and May, and then followed to June and September.
Researchers report that 76% of these patients had at least one symptom six months after symptoms began.
The most common symptoms were fatigue or muscle weakness (63%) along with trouble sleeping (26%) and anxiety or depression (23%).
"Because COVID-19 is such a new disease, we are only beginning to understand some of its long-term effects on patients' health," said researcher Dr. Bin Cao, from the National Center for Respiratory Medicine at the China-Japan Friendship Hospital and Capital Medical University, both in Beijing. His team published the findings in The Lancet journal Jan. 8.
"Our analysis indicates that most patients continue to live with at least some of the effects of the virus after leaving the hospital, and highlights a need for post-discharge care, particularly for those who experience severe infections," Cao said in a journal news release. "Our work also underscores the importance of conducting longer follow-up studies in larger populations in order to understand the full spectrum of effects that COVID-19 can have on people."
People who had been severely ill with COVID-19 more often had impaired lung function, as well as abnormalities seen in chest X-rays, which could indicate organ damage, six months after symptoms began, the Chinese researchers said.
Kidneys were also often affected. Based on lab tests, about 13% of patients who'd had normal kidney function while they'd been hospitalized showed reduced kidney function after they'd recovered from COVID-19, the researchers said.
One U.S. expert said post-COVID-19 "recovery" remains an ongoing, unfolding story.
"'Long COVID' is an evolving syndrome. Although the constellation of earlier associated symptoms is fairly well described, little is known about long-term outcomes," said Dr. Thomas Gut, associate chair of medicine at Staten Island University Hospital in New York City. And he's seen similar issues among patients at his hospital.
"As noted in this study, the vast majority of patients seen at our Post-COVID Recovery Center are for complaints of fatigue or brain fog, which both have overlap features with the complaints seen in this study," Gut said.
"Many of our patients report either new onset symptoms since COVID, or significantly worsened symptoms," he noted. "Most of our patients are seeing gradual improvement in symptoms as time passes, but some are still experiencing lingering effects nearly a year after infection. For many patients, there is little clear explanation for their persistent symptoms even after extensive testing and even less clear treatment options at this point."
Another expert believes health care centers need to be prepared for a wave of long COVID patients.
"There will be a wave of patients with long COVID entering our medical systems that will require continuing care and rehabilitation," said Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City. "We must not only plan for this, by developing centers of excellence, but allocate the necessary federal funds for research and care of these patients."
Beyond the physical issues experienced post-COVID, there's a "psychological toll on recovery, which directly impacts how people are able to resume their lives," Glatter added. "Having appropriate resources in place is essential for aiding recovery in the painful and long months after acute infection."
The Wuhan study also tried to track survivors' longer-term immunity against COVID-19. It found that levels of neutralizing antibodies against the new coronavirus fell by more than half (52.5%) after six months in 94 patients whose immune response was tested at the peak of the infection.
That finding increases concern about the possibility of survivors being reinfected by the virus.
"At this time, the duration of immunity after COVID-19 infection is unclear," Glatter said.
However, he pointed to another study released Thursday in the journal Science that "indicates that natural immunity to COVID-19 may last up to eight months, making the potential for reinfection less likely. It's a complex response involving antibodies, memory B-cells, and different types of T-cells."
But all of this means vaccination is still imperative, even for people who already had COVID-19, Glatter said.
"We still don't know the full picture of longer-term immunity, making vaccination an essential part of the public health approach to this pandemic," he said. "The vaccine is safe and effective and represents the most effective way to reach herd immunity."
Herd immunity occurs when enough people (about 70%) in a population have gained immunity against a virus, effectively stopping its further spread.
For more on COVID-19, see the U.S. Centers for Disease Control and Prevention.
SOURCES: Thomas Gut, DO, associate chair, medicine, Staten Island University Hospital, New York City; Robert Glatter, MD, emergency physician, Lenox Hill Hospital, New York City; The Lancet, news release, Jan. 8, 2021