Since the beginning of the pandemic, doctors have found that people who become very ill with COVID-19 often experience kidney problems, not just the lung impairments that are the hallmark of the illness.

Now, a large study suggests that kidney issues can last for months after patients recover from the initial infection and may lead to a serious lifelong reduction of kidney function in some patients.

The study, published Wednesday in the Journal of the American Society of Nephrology, found that the sicker Covid patients were initially, the more likely they were to experience lingering kidney damage.

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But even people with less severe initial infections could be vulnerable.

“You see really, across the board, a higher risk of a bunch of important kidney-associated events,” said Dr F. Perry Wilson, a nephrologist and associate professor of medicine at Yale, who was not involved in the study. “And what was particularly striking to me was that these persisted.”

Kidneys play a vital role in the body, clearing toxins and excess fluid from the blood, helping maintain a healthy blood pressure, and keeping a balance of electrolytes and other important substances. When the kidneys are not working properly or efficiently, fluids build up, leading to swelling, high blood pressure, weakened bones and other problems.

The heart, lungs, central nervous system and immune system can become impaired. In end-stage kidney disease, dialysis or an organ transplant may become necessary. The condition can be fatal.

The new study, based on records of patients in the Department of Veterans Affairs health system, analyzed data from 89,216 people who tested positive for the coronavirus between March 1, 2020, and March 15, 2021, as well as data from 1,637,467 people who were not Covid patients.

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Between one and six months after becoming infected, Covid survivors were about 35 per cent&nbsp;more likely than non-Covid patients to have kidney damage or substantial declines in kidney function, said Dr Ziyad Al-Aly, chief of the research and development service at the VA St. Louis Health Care System and senior author of the study.

“People who have survived the first 30 days of Covid are at risk of developing kidney disease,” Al-Aly, a nephrologist, said.

Because many people with reduced kidney function do not experience pain or other symptoms, “what’s really important is that people realize that the risk is there and that physicians caring for post-Covid patients really pay attention to kidney function and disease,” he said.

The two sets of patients in the study differed, in that members of one group had all been infected with Covid and members of the other group may have had a variety of other health conditions. Experts cautioned that there were limitations to the comparisons.

The researchers tried to minimize the differences with detailed analyses that adjusted for a long list of demographic characteristics, preexisting health conditions, medication usage and whether people were in nursing homes.

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Another limitation is that patients in the VA study were largely male and white, with a median age of 68, so it is unclear how generalizable the results are.

One strength of the research, experts said, is that it involves over 1.7 million patients with detailed electronic medical records, making it the largest study so far on Covid-related kidney problems.

While the results most likely would not apply to all Covid patients, they show that for those in the study, “there’s a pretty notable impact on kidney health in survivors of <a href="https://www.wionews.com/topics/coronavirus">COVID-19</a> over the long term, particularly those who were very sick during their acute illness,” said Dr C. John Sperati, a nephrologist and associate professor of medicine at Johns Hopkins, who was not involved in the study.

Other researchers have found similar patterns, “so this is not the only study suggesting that these events are transpiring after COVID-19 infection,” he added.

He and other experts said that if even a small percentage of the millions of Covid survivors in the United States developed lasting kidney problems, the impact on health care would be great.

To assess kidney function, the research team evaluated levels of creatinine, a waste product that kidneys are supposed to clear from the body, as well as a measure of how well the kidneys filter the blood called the estimated glomerular filtration rate.

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Healthy adults gradually lose kidney function over time, about 1 per cent&nbsp;or less a year, starting in their 30s or 40s, Wilson said. Serious illnesses and infections can cause more profound or permanent loss of function that may lead to chronic kidney disease or end-stage kidney disease.

The new study found that 4,757 COVID survivors had lost at least 30 per cent&nbsp;of kidney function in the year after their infection, Al-Aly said.

That is equivalent to roughly “30 years of kidney function decline,” Wilson said.

Covid patients were 25 per cent&nbsp;more likely to reach that level of decline than people who had not had the illness, the study found.

Smaller numbers of Covid survivors had steeper declines. But Covid patients were 44 per cent more likely than non-Covid patients to lose at least 40 per cent of kidney function and 62 per cent&nbsp;more likely to lose at least 50 per cent.

End-stage kidney disease, which occurs when at least 85 per cent of kidney function is lost, was detected in 220 Covid patients, Al-Aly said. Covid survivors were nearly three times as likely to receive the diagnosis as patients without Covid, the study found.

Al-Aly and his colleagues also looked at a type of sudden renal failure called acute kidney injury, which other studies have found in up to half of the hospitalised Covid patients. The condition can heal without causing long-term loss of kidney function.

But the VA study found that months after their infection, 2,812 Covid survivors suffered acute kidney injury, nearly twice the rate in non-covid patients, Al-Aly said.

Wilson said the new data supported results of a study of 1,612 patients that he and colleagues conducted that found that Covid patients with acute kidney injury had significantly worse kidney function in the months after leaving the hospital than people with acute kidney injuries from other medical conditions.

In the new study, researchers did not directly compare Covid survivors with people infected with other viruses, like the flu, making it hard to know “are you really any sicker than if you just had another bad infection,” Sperati said.

Doctors are unsure why COVID can cause kidney damage. Kidneys might be especially sensitive to surges of inflammation or immune system activation, or blood-clotting problems often seen in COVID patients may disturb kidney function, experts said.

Since the beginning of the pandemic, doctors have found that people who become very ill with COVID-19 often experience kidney problems, not just the lung impairments that are the hallmark of the illness.

Since the beginning of the pandemic, doctors have found that people who become very ill with COVID-19 often experience kidney problems, not just the lung impairments that are the hallmark of the illness. Now, a large study suggests that kidney issues can last for months after patients recover from the initial infection and may lead to a serious lifelong reduction of kidney function in some patients. The study, published Wednesday in the Journal of the American Society of Nephrology, found that the sicker Covid patients were initially, the more likely they were to experience lingering kidney damage. Also read | Study shows Brazilian viper venom may become tool in fight against COVID-19 But even people with less severe initial infections could be vulnerable. “You see really, across the board, a higher risk of a bunch of important kidney-associated events,” said Dr F. Perry Wilson, a nephrologist and associate professor of medicine at Yale, who was not involved in the study. “And what was particularly striking to me was that these persisted.” Kidneys play a vital role in the body, clearing toxins and excess fluid from the blood, helping maintain a healthy blood pressure, and keeping a balance of electrolytes and other important substances. When the kidneys are not working properly or efficiently, fluids build up, leading to swelling, high blood pressure, weakened bones and other problems. The heart, lungs, central nervous system and immune system can become impaired. In end-stage kidney disease, dialysis or an organ transplant may become necessary. The condition can be fatal. The new study, based on records of patients in the Department of Veterans Affairs health system, analyzed data from 89,216 people who tested positive for the coronavirus between March 1, 2020, and March 15, 2021, as well as data from 1,637,467 people who were not Covid patients. Also read | Drinking coffee reduces risk of contracting coronavirus: Study Between one and six months after becoming infected, Covid survivors were about 35 per cent more likely than non-Covid patients to have kidney damage or substantial declines in kidney function, said Dr Ziyad Al-Aly, chief of the research and development service at the VA St. Louis Health Care System and senior author of the study. “People who have survived the first 30 days of Covid are at risk of developing kidney disease,” Al-Aly, a nephrologist, said. Because many people with reduced kidney function do not experience pain or other symptoms, “what’s really important is that people realize that the risk is there and that physicians caring for post-Covid patients really pay attention to kidney function and disease,” he said. The two sets of patients in the study differed, in that members of one group had all been infected with Covid and members of the other group may have had a variety of other health conditions. Experts cautioned that there were limitations to the comparisons. The researchers tried to minimize the differences with detailed analyses that adjusted for a long list of demographic characteristics, preexisting health conditions, medication usage and whether people were in nursing homes. Also read | WHO warns against a new Covid variant that may be resistant to vaccines Another limitation is that patients in the VA study were largely male and white, with a median age of 68, so it is unclear how generalizable the results are. One strength of the research, experts said, is that it involves over 1.7 million patients with detailed electronic medical records, making it the largest study so far on Covid-related kidney problems. While the results most likely would not apply to all Covid patients, they show that for those in the study, “there’s a pretty notable impact on kidney health in survivors of COVID-19 over the long term, particularly those who were very sick during their acute illness,” said Dr C. John Sperati, a nephrologist and associate professor of medicine at Johns Hopkins, who was not involved in the study. Other researchers have found similar patterns, “so this is not the only study suggesting that these events are transpiring after COVID-19 infection,” he added. He and other experts said that if even a small percentage of the millions of Covid survivors in the United States developed lasting kidney problems, the impact on health care would be great. To assess kidney function, the research team evaluated levels of creatinine, a waste product that kidneys are supposed to clear from the body, as well as a measure of how well the kidneys filter the blood called the estimated glomerular filtration rate. Healthy adults gradually lose kidney function over time, about 1 per cent or less a year, starting in their 30s or 40s, Wilson said. Serious illnesses and infections can cause more profound or permanent loss of function that may lead to chronic kidney disease or end-stage kidney disease. The new study found that 4,757 COVID survivors had lost at least 30 per cent of kidney function in the year after their infection, Al-Aly said. That is equivalent to roughly “30 years of kidney function decline,” Wilson said. Covid patients were 25 per cent more likely to reach that level of decline than people who had not had the illness, the study found. Smaller numbers of Covid survivors had steeper declines. But Covid patients were 44 per cent more likely than non-Covid patients to lose at least 40 per cent of kidney function and 62 per cent more likely to lose at least 50 per cent. End-stage kidney disease, which occurs when at least 85 per cent of kidney function is lost, was detected in 220 Covid patients, Al-Aly said. Covid survivors were nearly three times as likely to receive the diagnosis as patients without Covid, the study found. Al-Aly and his colleagues also looked at a type of sudden renal failure called acute kidney injury, which other studies have found in up to half of the hospitalised Covid patients. The condition can heal without causing long-term loss of kidney function. But the VA study found that months after their infection, 2,812 Covid survivors suffered acute kidney injury, nearly twice the rate in non-covid patients, Al-Aly said. Wilson said the new data supported results of a study of 1,612 patients that he and colleagues conducted that found that Covid patients with acute kidney injury had significantly worse kidney function in the months after leaving the hospital than people with acute kidney injuries from other medical conditions. In the new study, researchers did not directly compare Covid survivors with people infected with other viruses, like the flu, making it hard to know “are you really any sicker than if you just had another bad infection,” Sperati said. Doctors are unsure why COVID can cause kidney damage. Kidneys might be especially sensitive to surges of inflammation or immune system activation, or blood-clotting problems often seen in COVID patients may disturb kidney function, experts said.

Another hidden Covid risk: Lingering kidney problems

Children were earlier thought to be safe from the Wuhan virus.

In April 2020, the United Nations in a policy brief had said: "Children are not the face of the pandemic, they have been largely spared from the direct health effects of COVID-19."

Watch:

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However, a Harvard study in August 2020 had called children the silent spreaders of the virus. In short, children were considered to be carriers, not victims of the virus.

One year into the pandemic, children have been dying of the Wuhan virus. Babies as young as 1.5 months are in need of medical intervention. They are showing symptoms like fever, cough and cold.&nbsp;

There are also asymptomatic cases, again. For the longest time it was thought that asymptomatic children have low levels of infection. However, now it turns out that theory may no longer be true.

Asymptomatic children are now developing&nbsp;life-threatening complications weeks after being infected.&nbsp;

A tweet about one such case was widely shared a few days ago. It was an account of a mother whose 11-year-old son had developed a rare and dangerous illness called MISC or multisystem inflammatory syndrome in children.

The mother wrote her son had bloodshot eyes, rash all over his body and continuous vomitin.&nbsp;She said her son had difficulty staying up and responding.

The child had developed a multi-organ inflammation by the time he was taken to the hospital and examined. The mother said, "we were told that if he would not have been admitted when we did, we would have missed the boat".

The child began showing symptoms of MISC at least four&nbsp;weeks after being infected by the virus. But no one knew the child even had COVID-19 at first since he was asymptomatic.

It took a life-threatening illness for the cat to come out of the bag.

MISC was first linked to the Wuhan virus in April 2020. Pediatric doctors from London reported cases of the immune system in children being triggered inappropriately after being infected by the virus.

Now, one year later, the world still does not have a way to stop it since there are no vaccines for children, at least the majority of them.

In the Indian state of Maharashtra alone, more than 60,000 children have tested positive for the Wuhan virus between March 1 and April 4.

There is an information deficit, with no awareness about the kind of symptoms kids may show when infected or about MISC.

Children have been battling the second wave unshielded. They are also bracing for a third wave as latest estimates say the third wave will hit India by October 2021, which is five months from now.

The only way to protect children is by getting them vaccinated. However, only a couple of rich countries have begun vaccinating kids.

In the United States, children between the age group of 12 to 15 will now be able to take the Pfizer-BionTech vaccine.

Pfizer's vaccine has been tested in the 12 to 15 age group. They were given the same dosage as adults and they showed the same side effects - sore arms, &nbsp;chills and aches.

Last week, Canada included those above the age of 12 in&nbsp;its inoculation programme. The EU is likely to follow suit.

Authorities say the European Union could approve the Pfizer jab for children above the age of 12 as early as this month.

Vaccine trials have been going on in children as young as 6 months old. While it may sound morally wrong to many, it is the only way out.

Vaccination is the only way out of the pandemic, with jabs for&nbsp;both children and adults.

Children were earlier thought to be safe from the Wuhan virus. In April 2020, the United Nations in a policy brief had said: "Children are not the face of the pandemic, they have been largely spared from the direct health effects of COVID-19.

Children were earlier thought to be safe from the Wuhan virus. In April 2020, the United Nations in a policy brief had said: "Children are not the face of the pandemic, they have been largely spared from the direct health effects of COVID-19." Watch: However, a Harvard study in August 2020 had called children the silent spreaders of the virus. In short, children were considered to be carriers, not victims of the virus. One year into the pandemic, children have been dying of the Wuhan virus. Babies as young as 1.5 months are in need of medical intervention. They are showing symptoms like fever, cough and cold. There are also asymptomatic cases, again. For the longest time it was thought that asymptomatic children have low levels of infection. However, now it turns out that theory may no longer be true. Asymptomatic children are now developing life-threatening complications weeks after being infected. A tweet about one such case was widely shared a few days ago. It was an account of a mother whose 11-year-old son had developed a rare and dangerous illness called MISC or multisystem inflammatory syndrome in children. The mother wrote her son had bloodshot eyes, rash all over his body and continuous vomitin. She said her son had difficulty staying up and responding. The child had developed a multi-organ inflammation by the time he was taken to the hospital and examined. The mother said, "we were told that if he would not have been admitted when we did, we would have missed the boat". The child began showing symptoms of MISC at least four weeks after being infected by the virus. But no one knew the child even had COVID-19 at first since he was asymptomatic. It took a life-threatening illness for the cat to come out of the bag. MISC was first linked to the Wuhan virus in April 2020. Pediatric doctors from London reported cases of the immune system in children being triggered inappropriately after being infected by the virus. Now, one year later, the world still does not have a way to stop it since there are no vaccines for children, at least the majority of them. In the Indian state of Maharashtra alone, more than 60,000 children have tested positive for the Wuhan virus between March 1 and April 4. There is an information deficit, with no awareness about the kind of symptoms kids may show when infected or about MISC. Children have been battling the second wave unshielded. They are also bracing for a third wave as latest estimates say the third wave will hit India by October 2021, which is five months from now. The only way to protect children is by getting them vaccinated. However, only a couple of rich countries have begun vaccinating kids. In the United States, children between the age group of 12 to 15 will now be able to take the Pfizer-BionTech vaccine. Pfizer's vaccine has been tested in the 12 to 15 age group. They were given the same dosage as adults and they showed the same side effects - sore arms, chills and aches. Last week, Canada included those above the age of 12 in its inoculation programme. The EU is likely to follow suit. Authorities say the European Union could approve the Pfizer jab for children above the age of 12 as early as this month. Vaccine trials have been going on in children as young as 6 months old. While it may sound morally wrong to many, it is the only way out. Vaccination is the only way out of the pandemic, with jabs for both children and adults.

Why children need to be protected from the virus

The Wuhan Coronavirus outbreak is hitting China's belt and road initiative. Projects funded by China are stuck. Chinese workers are unable to return to work. This report has the details.

Gravitas: Wuhan Virus, China's belt and road projects grind to a halt