Tag: Corona Updates

COVID-19 Government Guidelines Medical Equipments Medical Updates

Circovirus involved in human hepatitis: Study

Post author By Pragya sharma
Post date February 23, 2023
No Comments on Circovirus involved in human hepatitis: Study

Circoviruses are a family of small, highly resistant DNA viruses that were initially identified in 1974 in various animal species, where they can cause respiratory, renal, dermatological and reproductive problems. HCirV-1 is a novel virus that is distant from known animal circoviruses.

Scientists from the Institut Pasteur, Necker-Enfants Malades Hospital (AP-HP), Inserm in the Imagine Institute, Universite Paris Cite and the Alfort National Veterinary School (EnvA) have identified a previously unknown species of circovirus, provisionally named human circovirus 1 (HCirV-1).

Circoviruses are a family of small, highly resistant DNA viruses that were initially identified in 1974 in various animal species, where they can cause respiratory, renal, dermatological and reproductive problems. HCirV-1 is a novel virus that is distant from known animal circoviruses. It was shown to be implicated in damage to the liver of a patient undergoing immunosuppressive treatment. This discovery of the first circovirus in humans, linked to hepatitis, was published in the journal Emerging Infectious Diseases on January 3, 2023.

Although the transmission of animal viruses to humans is regularly reported in the scientific literature, it is rare for a novel virus to be identified in a patient in Europe. But as part of a recent study, scientists and physicians have identified the first circovirus involved in human hepatitis. “The patient had unexplained chronic hepatitis, with few symptoms. She had received a heart-lung transplant 17 years earlier and had been monitored regularly since. We had access to a large number of samples over several years and were therefore able to identify this novel virus, which was completely unexpected,” explains Marc Eloit, last author of the study, Head of the Institut Pasteur’s Pathogen Discovery laboratory and a Professor of Virology at the Alfort National Veterinary School (EnvA). His laboratory specializes in the identification of pathogens in patients suspected of severe infection of unknown cause.

In March 2022, in collaboration with the Department of Clinical Microbiology at Necker-Enfants Malades Hospital (AP-HP), the pathological tissue samples of this 61-year-old female patient receiving immunosuppressive treatment, whose hepatitis had no identifiable cause, were sequenced to search for microbial sequences. The RNA (ribonucleic acid) sequences extracted from the tissues were analyzed and compared with those of known microbes. “The aim is to identify sequences of interest among all the sequences obtained, which is like searching for a needle in a haystack!” continues the scientist Marc Eloit. These thousands of RNA sequences were analyzed in parallel using mNGS (metagenomic next-generation sequencing) high-throughput sequencing techniques and sophisticated algorithms. After ruling out common etiologies, the analysis led to the identification of a previously unknown species of circovirus, provisionally named human circovirus 1 (HCirV-1). No other viral or bacterial sequence was found.

The involvement of HCirV-1 in the hepatitis was then demonstrated by analyzing samples taken from the patient in previous years as part of her post-transplant treatment. The results showed that the HCirV-1 viral genome was undetectable in the blood samples from 2017 to 2019, then that its concentration peaked in September 2021. Viral replication in liver cells was demonstrated (2 to 3% of liver cells were infected), pointing to the role of HCirV-1 in liver damage: once the virus has used the resources in the liver cell to replicate, it destroys the cell.

From November 2021 onwards, following antiviral treatment, the patient’s liver enzymes returned to normal levels, indicating the end of hepatic cytolysis.

Diagnosing hepatitis of unknown etiology remains a major challenge, as shown by the cases of acute hepatitis reported in children in the United Kingdom and Ireland last April and signaled by WHO. “We need to know the cause of the hepatitis, and especially whether or not it is viral, to be able to offer suitable treatment and monitor patients effectively. The identification of this novel virus that is pathogenic in humans, and the development of a test that can be performed by any hospital laboratory, offers a new tool for diagnosing and monitoring patients with hepatitis,” stresses Anne Jamet from the Department of Clinical Microbiology at Necker-Enfants Malades Hospital (AP-HP), who is also affiliated with Inserm and co-last author of the study.

Although some circoviruses are pathogenic for animals and vaccines can be administered, especially in pigs, this is the first known circovirus to be pathogenic for humans. The patient’s symptoms remained mild; the virus was able to be identified because she was being closely monitored following her combined transplant. The origin of the virus — whether it is circulating in humans or of animal origin — has yet to be identified, and the source of infection (contact, food, etc.) remains unknown. Following their discovery, the scientists developed a specific PCR test that is now available for etiological diagnosis of hepatitis of unknown origin. A serological test is also being developed.

“These results show the value of this type of sequencing analysis in identifying novel or unexpected pathogens. It is always important for clinicians to know whether or not an infection is viral so that they can adapt the treatment accordingly. It is also crucial to be able to identify a novel pathogen when an infection remains unexplained and to develop a diagnostic test, because any new case of human infection with an emerging pathogen may potentially signal the start of an outbreak,” concludes Marc Eloit. The test is available for the medical community and can now be easily performed for other cases of unexplained hepatitis.

Adenovirus cases spike in West Bengal: Symptoms, treatment and precautions

Post author By Pragya sharma
Post date February 21, 2023
No Comments on Adenovirus cases spike in West Bengal: Symptoms, treatment and precautions

Adenovirus: Adenovirus causes mild cold or flu-like illness which can affect people of all ages, according to US Centers for Disease Control and Prevention (CDC).

Bengal health authorities have been asked to be vigilant after the state recorded a big spike in adenovirus cases that has led to pediatric wards in state-run and private hospitals filling up fast. Health officials say at least 32 per cent of samples sent to the National Institute of Cholera and Enteric Diseases (ICMR-NICED) in Kolkata since January have tested positive for the virus. Two children – a six-month-old boy and 2.5-year-old girl – died Sunday, though the cause of deaths has not yet been formally identified as the adenovirus, which causes a mild cold, or flu-like, illness that can affect people of all ages.

Symptoms:

Infected people may have relatively mild symptoms like a cold or flu, a fever, and a sore throat, or acute bronchitis, pneumonia, conjunctivitis and acute gastroenteritis, which is an inflammation of stomach. Adenovirus can cause mild and severe illnesses but the latter is relatively uncommon. People with weak immune systems, existing respiratory or cardiac diseases are at higher risk of developing severe illness from adenovirus.

Transmission:

The virus is usually transmitted by physical contact with an infected person, the United States’ Centers for Disease Control and Prevention said. It can also be spread through the air (via coughs and sneezes) or a patient’s stool; for example, while changing diapers.

Treatment:

There is currently no specific course of treatment or approved antiviral medication. Since most cases are mild, they are managed by pain-killlers or medication to manage symptoms.

Doctors suggest the best way to tackle the infection is prevention. Steps to avoid getting infected include avoiding touching your eyes, nose or mouth with contaminated hands and to regularly use soap or sanitiser to wash your hands.

COVID-19 infection increases diabetes risk: Research

Post author By Pragya sharma
Post date February 20, 2023
No Comments on COVID-19 infection increases diabetes risk: Research

Diabetes disrupts normal metabolism and metabolic processes, preventing the pancreas from producing enough insulin, a hormone that helps regulate blood levels of glucose and amino acids.

Those who have undergone COVID-19 have a higher risk of having new-onset diabetes, which is the main cause of cardiovascular disease, according to research from Cedars-Smidt Sinai’s Heart Center.

The findings, published in the journal JAMA Network Open, also suggest that the risk of Type 2 diabetes appears lower in individuals who were already vaccinated against COVID-19 by the time they were infected.

“Our results verify that the risk of developing Type 2 diabetes after a COVID-19 infection was not just an early observation but, in fact, a real risk that has, unfortunately, persisted through the Omicron era,” said Alan Kwan, MD, first and corresponding author of the study and a cardiovascular physician in the Smidt Heart Institute at Cedars-Sinai.

The trend, Kwan says, is concerning because most people in the United States will eventually experience a COVID-19 infection. “This research study helps us understand–and better prepare for–the post-COVID-19 era of cardiovascular risk,” Kwan said.

To determine the rising rates of diabetes, investigators evaluated medical records from 23,709 adult patients who had at least one documented COVID-19 infection and were treated within the Cedars-Sinai Health System in Los Angeles from 2020-2022. The average patient was 47 years old, and 54% of subjects were female.

Within the study time frame:

– The combined risk of Type 2 diabetes after COVID-19 exposure–accounting for both vaccinated and unvaccinated patients–was 2.1%, with 70% occurring after COVID-19 infection versus 30% happening prior to COVID-19 exposure.

– The risk of Type 2 diabetes after COVID-19 exposure for unvaccinated patients was 2.7%, with 74% occurring after COVID-19 infection versus 26% happening prior to COVID-19 exposure.

– The risk of Type 2 diabetes after COVID-19 exposure for vaccinated patients was 1.0%, with 51% occurring after COVID-19 infection versus 49% happening prior to COVID-19 exposure.

“These results suggest that COVID-19 vaccination prior to infection may provide a protective effect against diabetes risk,” said Kwan. “Although further studies are needed to validate this hypothesis, we remain steadfast in our belief that COVID-19 vaccination remains an important tool in protecting against COVID-19 and the still-uncertain risks that people may experience during the post-infection period.”

Susan Cheng, MD, MPH, senior author of the study, professor of Cardiology, and director for Cardiovascular Population Sciences in the Smidt Heart Institute, says these findings broaden the medical field’s understanding of the effects of COVID-19 on the body, while simultaneously unearthing yet-to-be-answered questions.

“Although we don’t yet know for certain, the trends and patterns that we see in the data suggest that COVID-19 infection could be acting in certain settings like a disease accelerator, amplifying risk for a diagnosis that individuals might have otherwise received later in life,” said Cheng, the Erika J. Glazer Chair in Women’s Cardiovascular Health and Population Science. “So, it could be that instead of being diagnosed with diabetes by age 65, a person with preexisting risk for diabetes might–after a COVID-19 infection–be more likely to develop diabetes by age 45 or 55.”

Diabetes disrupts normal metabolism and metabolic processes, preventing the pancreas from producing enough insulin, a hormone that helps regulate blood levels of glucose and amino acids. Because diabetes can damage vital organs and blood vessels, people with diabetes are at higher risk for heart attack and stroke.

The disease affects an estimated 26 million people in the United States.

This research, Kwan says, is one piece of the puzzle that will help researchers understand how to prevent metabolic as well as cardiovascular disease risk in the future.

“As we learn how to live with COVID-19, we also have to be prepared to recognize and treat the various conditions linked to its aftereffects,” said Kwan. “Our ultimate goal–with every research study we conduct–is to find ways to keep people healthy and able to engage in their everyday activities and lives.”

Organ damage persists in 59% of long Covid patients a year after diagnosis: Study

Post author By Pragya sharma
Post date February 16, 2023
No Comments on Organ damage persists in 59% of long Covid patients a year after diagnosis: Study

Scientists have found that organ damage persisted in 59 per cent of long Covid patients a year after initial symptoms, even in those not severely affected when first diagnosed with the virus, according to a new study.

Scientists have found that organ damage persisted in 59 per cent of long Covid patients a year after initial symptoms, even in those not severely affected when first diagnosed with the virus, according to a new study. The study also found that 29 per cent of patients with long COVID had multi-organ impairment, with persistent symptoms and reduced function at six and twelve months, it said.

The comprehensive study of organ impairment in long COVID patients over 12 months focused on patients reporting extreme breathlessness, cognitive dysfunction and poor health-related quality of life, it said.

According to the study, of the 536 patients who were studied, 13 per cent were hospitalised when first diagnosed with COVID-19, with 32 per cent of people taking part in the study being healthcare workers.

The study found that of the 536 patients, 331, or 62 per cent, were identified with organ impairment six months after their initial diagnosis. It is published in the Journal of the Royal Society of Medicine.

These patients were followed up six months later with a 40-minute multi-organ MRI scan (Perspectum’s CoverScan), analysed in Oxford, the study said.

“Symptoms were common at six and twelve months and associated with female gender, younger age and single organ impairment,” said Amitava Banerjee, Professor of Clinical Data Science at the UCL Institute of Health Informatics, UK.

The study reported a reduction in symptoms between six and 12 months, it said. Extreme breathlessness came down from being reported in 38 per cent of the patients to 30 per cent of patients, the study said, while cognitive dysfunction came down from 48 per cent to 38 per cent.

Poor health-related quality of life came down from 57 per cent to 45 per cent of patients, the study said.

“Several studies confirm persistence of symptoms in individuals with long COVID up to one year.

“We now add that three in five people with long COVID have impairment in at least one organ, and one in four have impairment in two or more organs, in some cases without symptoms,” said Banerjee.

“Impact on quality of life and time off work, particularly in healthcare workers, is a major concern for individuals, health systems and economies.

“Many healthcare workers in our study had no prior illness, but of 172 such participants, 19 were still symptomatic at follow-up and off work at a median of 180 days,” said Banerjee.

The underlying mechanisms of long COVID remain elusive, said the researchers, who did not find evidence by symptoms, blood investigations or MRI to clearly define long COVID subtypes, the study said.

They said that future research must consider associations between symptoms, multi-organ impairment and function in larger cohorts.

“Organ impairment in long COVID has implications for symptoms, quality of life and longer-term health, signalling the need for prevention and integrated care for long COVID patients,” said Banerjee.

Free sugars linked with higher risk of cardiovascular disease: Study

Post author By Pragya sharma
Post date February 15, 2023
No Comments on Free sugars linked with higher risk of cardiovascular disease: Study

The authors suggest that replacing free sugars with non-free sugars – mostly those naturally occurring in whole fruits and vegetables – and a higher fibre intake, may help protect against cardiovascular disease.

An increased diet of free sugars – both added sugars and those found naturally in honey and fruit juice linked to an increased risk of cardiovascular disease, according to a study. The findings support the global dietary recommendation to limit free sugar consumption to less than 5 per cent of total daily energy consumption.

The findings of the study were published in BMC Medicine.

Rebecca Kelly and colleagues analysed data from 110,497 individuals from the UK Biobank who had completed at least two dietary assessments. The researchers tracked individuals for around 9.4 years and during this time, total cardiovascular disease (heart disease and stroke combined), heart disease, and stroke occurred in 4,188, 3,138, and 1,124 participants, respectively.

The authors found total carbohydrate intake was not associated with cardiovascular disease outcomes. However, when looking at the types and sources of carbohydrates consumed, they found that higher free sugar intake from foods such as sugary drinks, fruit juice and sweets, was associated with increased risk of all cardiovascular disease outcomes. For each 5% higher total energy from free sugars, the associated risk of total cardiovascular disease was 7% higher. The authors found that the risk of heart disease was 6% higher, while the risk of stroke was 10% higher. Additionally, consuming five grams higher fibre per day was associated with 4% lower risk of total cardiovascular disease, but this association did not remain significant after accounting for body mass index (BMI).

The authors suggest that replacing free sugars with non-free sugars – mostly those naturally occurring in whole fruits and vegetables – and a higher fibre intake, may help protect against cardiovascular disease.

Paxlovid reduced hospitalisation, death risk during Omicron wave: Study

Post author By Pragya sharma
Post date February 14, 2023
No Comments on Paxlovid reduced hospitalisation, death risk during Omicron wave: Study

Antiviral drug, paxlovid, significantly reduced the likelihood of hospitalisation or death from COVID-19 in people at risk of severe illness during the Omicron wave, according to a study.

Antiviral drug, paxlovid, significantly reduced the likelihood of hospitalisation or death from COVID-19 in people at risk of severe illness during the Omicron wave, according to a study. The research, published in the Canadian Medical Association Journal, aimed to evaluate the effectiveness of paxlovid, a combiantion of nirmatrelvir and ritonavir drugs, in preventing severe illness during the emergence of the Omicron variant.

The researchers from Public Health Ontario looked at data on adults with mild disease in Ontario, Canada who tested positive for SARS-CoV-2 by polymerase chain reaction (PCR) test between April 4 and August 31, 2022.

They compared 8,876 patients treated with nirmatrelvir–ritonavir with 1,68, 669 who were not treated. Most patients were older than 70 years, were vaccinated and had potential drug–drug interactions.

A previous randomised controlled trial conducted before the emergence of the Omicron variant had found nirmatrelvir–ritonavir to be effective at treating patients.

However, that trial did not include people who had been vaccinated or who had potential drug–drug interactions.

“Our study, in conjunction with previous clinical trials and observational research, supports the effectiveness of nirmatrelvir–ritonavir at reducing hospital admission from COVID-19 and all-cause death,” said study lead author Kevin Schwartz from Public Health Ontario.

The researchers found that for every 62 people treated with nirmatrelvir–ritonavir, the medication prevented one case of severe COVID-19.

“This study highlights the importance of testing for SARS-CoV-2 if you have symptoms, and access to Paxlovid for those at risk for severe COVID-19,” Schwartz said.

“If you test positive for COVID-19, are over 60 years of age, or if you have other risk factors for severe infection, such as chronic medical conditions or are undervaccinated, contact your health care provider or pharmacy within 5 days of symptoms starting and ask about Paxlovid,” the scientist added.

Actual Covid infections in India 17 times higher than reported: BHU study

Post author By Pragya sharma
Post date February 11, 2023
No Comments on Actual Covid infections in India 17 times higher than reported: BHU study

Synopsis

According to government data, nearly 4.5 crore people in India have been infected with COVID-19 so far. However, the study published in the International Journal of Infectious Diseases (IJID) estimated that the actual coronavirus cases in the country may be between 58 to 98 crores.

The actual COVID-19 infections in India may be around 17 times higher than the official figure, a study led by researchers at Banaras Hindu University (BHU) suggests. According to government data, nearly 4.5 crore people in India have been infected with COVID-19 so far. However, the study published in the International Journal of Infectious Diseases (IJID) estimated that the actual coronavirus cases in the country may be between 58 to 98 crores.

The research “has shown that the actual corona infection in India was at least 17 times higher,” according to a statement by BHU.

“The discrepancy observed in our study is due to the overwhelming number of asymptomatic people, which was several-fold higher than the true official infection,” said BHU geneticist Professor Gyaneshwer Chaubey.

“Asymptomatic cases were more inclined towards the younger population,” Chaubey, who led the study, told PTI.

The study involved 88 scientists from 34 research institutes across the country.

The team conducted serosurvey (antibody testing) among 2,301 individuals in urban areas of fourteen Indian districts in six states during the month of September-December 2020.

The most striking aspect of this study was that a large proportion of the Indian population was asymptomatic for COVID infection and the age group 26-35 had the maximum number of asymptomatic people, the researchers said.

The team conducted the research among a large number of people — street vendors — living in urban areas from fourteen Indian districts who are most at risk of corona infection.

“For the first time, we have used a novel approach to estimate the frequency of people infected in a certain geographical region,” said BHU’s Prajjval Pratap Singh, the study’s first author.

Samples were taken of only those people who self-reported that they never had any Covid symptoms or positive RT PCR test.

The minimum proportion of antibody-positive people was observed in Raipur district of Chhattisgarh (2 per cent), while the maximum proportion of antibody-positive persons was found in Ghazipur district (47 per cent) of Uttar Pradesh.

The research also revealed that the cases reported by the government were several times lower than the actual incidence of infection.

Through mathematical calculations, it was estimated that the actual corona cases in India are between 58 to 98 crores, the researchers said.

“The extensive serosurveillance has enabled us to have a clear picture rather than antigen testing or RT-PCR test,” said Professor VN Mishra from BHU, who led the medical testing in the study.

India on Wednesday recorded 96 fresh COVID-19 cases, while the number of active cases increased to 1,785, according to Union health ministry data.

With the new cases, the total tally stands at 4.46 crore (4,46,83,639). The death toll increased to 5,30,746 with one death reported from Uttara pardesh the data stated.

India reports 109 new covid cases

Post author By Pragya sharma
Post date February 9, 2023
No Comments on India reports 109 new covid cases

Covid cases are declining across the country with daily and weekly positivity recorded at 0.08%.

India has reported 109 new covid cases in the last 24 hours, with active cases declining to 1,781, the union health ministry data on Thursday showed. ‘

The total number of covid cases has reached 4.47 crore, and covid related deaths stood at 530,748 since the onset of covid pandemic.

Covid cases are declining across the country with daily and weekly positivity recorded at 0.08%.

Karnataka reported 108 active cases while Kerala has 1218 active cases. Maharashtra has 83 active cases, Odisha 88 cases, Rajasthan 10 cases, Tamil Nadu 36 active cases, Uttar Pradesh 16 and West Bengal 43 cases.

Around 4,41,51,219 people have recovered from the infection with the current recovery rate touching 98.81%.

With the rapid decline in the trajectory of covid cases, scientists believe that Omicron and its sub-lineages will not affect India as large number of populations is already exposed to the virus and vaccinated. Scientists say that people in India have developed hybrid immunity (due to vaccination and natural infection). However, they suggest people wear masks in crowded places and complete their vaccination doses if not done yet.

India reports 109 new covid cases

At present, large number of cases are being reported in China and other countries as a result of which the government has tightened covid preparedness measures. The government has directed the INSACOG under the supervision of Department of Biotechnology (DBT) to keep a close watch on covid situation in the country and continue to do constant genome sequencing to track any new variant.

The government is conducting RT-PCR testing for people returning from China, Hong Kong, Japan, Singapore, Thailand, and South Korea and mandated the filling up of ‘Air Suvidha’ forms for travelers from six countries under which 72-hour prior RT-PCR testing is compulsory.

The country has conducted over 1,41,248 tests in the last 24 hours taking the total trajectory of covid testing to 91.67 crore so far.

Under the covid vaccination drive, more than 220.61 crore vaccine doses have been administered to the people across the country so far. In the last 24 hours, around 1,13,507 vaccine doses were administered.

Besides, surveillance at the hospital level is also going on to monitor lnfluenza-like illness (lLl) & SARI cases.

Merck covid drug linked to new virus mutations, study says

Post author By Pragya sharma
Post date February 6, 2023
No Comments on Merck covid drug linked to new virus mutations, study says

Some researchers worry the drug may create more contagious or health-threatening variations of Covid, which has killed more than 6.8 million people globally over the past three years.

Merck & Co.’s Covid-19 pill is giving rise to new mutations of the virus in some patients, according to a study that underscores the risk of trying to intentionally alter the pathogen’s genetic code.

Some researchers worry the drug may create more contagious or health-threatening variations of Covid, which has killed more than 6.8 million people globally over the past three years.

Mutations linked to the use of Merck’s pill, Lagevrio, have been identified in viral samples taken from dozens of patients, according to a preprint study from researchers in the US and at the Francis Crick Institute, Imperial College London and other UK institutions.

The drug-linked mutations of the virus haven’t been shown to be more immune-evasive or lethal yet, according to the study published Friday without peer review on the medRxiv website. But their very existence highlights what some scientists say are potential risks in wider use of the drug, which was recently cleared in China.

Lagevrio works by creating mutations in the Covid genome that prevent the virus from replicating in the body, reducing the chances it will cause severe illness. Some scientists had warned before it was authorized in late 2021 that by virtue of how it works, the drug could give rise to mutations that could turn out to be problematic. The preprint paper has reawakened those worries about the Merck drug.

“There’s always been this underlying concern that it could contribute to a problem generating new variants,” said Jonathan Li, a virologist at Harvard Medical School and Brigham and Women’s Hospital in Boston. “This has largely been hypothetical, but this preprint validates a lot of those concerns.”

Merck covid drug linked to new virus mutations, study says

Merck Response

Merck disputes the view that its drug is causing problematic variants.

“There is no evidence to indicate that any antiviral agent has contributed to the emergence of circulating variants,” Merck spokesman Robert Josephson said in an email in response to questions about the study. “Based on available data we do not believe that Lagevrio (molnupiravir) is likely to contribute to the development of new meaningful coronavirus variants.”

He said new mutations have emerged over the course of the pandemic due to the virus spreading uncontrollably and Lagevrio can form an important part of the solution, he said. Merck pointed to research done in animals that showed its drug didn’t cause mutations.

The study authors assume the mutations were associated with molnupiravir treatment, but don’t have direct proof that the mutations arose in patients who took their drug, Josephson said in a follow-up email. Instead, the researchers drew their conclusions from “circumstantial associations between viral sequence origin and timeframe of sequence collection in countries where molnupiravir is available,” Josephson said

Merck fell as much as 1.2% in New York Wednesday, recovering some losses to close down 0.4%.

The US Food and Drug Administration, which authorized Lagevrio in late 2021, said it doesn’t comment on third-party research and works with Covid drugmakers to assess their products’ activity against variants.

Preprint

Major scientific journals don’t publish studies until the completion of a “peer review” process in which the research is scrutinized by outside experts. During the pandemic, scientists increasingly started publishing their research on what are known as “preprint servers” prior to exhaustive reviews, in attempt to advance the science more quickly and share urgent findings.

Researchers found Lagevrio-induced mutations in small patient clusters, indicating the new versions were spreading among them. While the biggest group they found with similar mutations was 21 people, that may not fully represent the true scope of the problem as viral samples of many patients aren’t analyzed, according to Ryan Hisner, an independent researcher from Indiana who helped write the paper.

The researchers looked at some 13 million viral genomes in databases around the world. The drug-linked mutations were proportionally more common in countries and groups where Lagevrio was likely to be used, especially the US and Australia, where it was introduced early. The signature mutations are less frequent in Canada, France, and other countries where the drug isn’t used.

“These effects are visible in these databases,” said Theo Sanderson, a Crick Institute geneticist who led the study. “It appears that people are being treated, some of them aren’t clearing their infections, and some are passing them on.”

The risk of drug-linked mutations is too great to continue using Merck’s drug, Hisner said. The US should explore authorizing drugs used in other countries to control Covid, like Xocova from Japan-based Shionogi & Co., and discontinue use of Lagevrio, said Michael Lin, a Stanford University antiviral drug researcher who said he consulted with the authors but wasn’t involved in the study. China cleared Lagevrio late last year and Shionogi said it’s in the final stages of discussions with the country’s regulators over its Covid drug.

It’s a very distressing situation,” said Lin. “There’s no evidence that any of these mutants is worse in any way — not yet — but it’s well agreed that you’re playing with fire if you’re creating random mutations and hoping nothing bad will come of it.”

Sanderson declined to comment on whether doctors should continue using Merck’s drug, saying the study doesn’t address the issue.

Lingering concerns

Concerns about Lagevrio’s safety and effectiveness are longstanding. Health officials recommend against its use in pregnant women. In general, the drug shouldn’t be used when alternatives are available, according to the US National Institutes of Health.

Merck was encouraged by former Warp Speed science czar Moncef Slaoui to team up with Ridgeback Biotherapeutics LP to get the much-needed oral Covid pill ready for widespread use. Early results showed it cut the risk of hospitalization and death by about 50% in non-immunized people.

Subsequent studies have indicated it’s actually less effective than those early trials indicated. A study released in December showed that adding Lagevrio to standard care didn’t reduce hospitalizations or deaths in high-risk adults, although the time to recovery from symptoms was shortened by several days.

However, Covid treatment options are dwindling. Variants have mutated to evade Covid antibodies made by Regeneron Pharmaceuticals Inc., Eli Lilly & Co. and Vir Biotechnology Inc. The last one to retain effectiveness, AstraZeneca Plc’s Evusheld, was just removed from the US market. That leaves few alternatives for Americans: just Paxlovid and Gilead Sciences Inc.’s remdesivir, which must be infused in three daily sessions as soon as someone is diagnosed.

Some patients aren’t eligible to take Paxlovid because it contains a component, called ritonavir, that has adverse interactions with therapies for other conditions like heart disease, that are common in people vulnerable to severe Covid.

Raymond Schinazi, an Emory University researcher, raised concerns about Merck’s drug early on in its development. He’d done his own research into it years ago before abandoning it.

He called for more monitoring to investigate whether the viruses with drug-linked mutations are having any impact after learning about the new study.

The preprint study is “an orange flag, not a red flag yet,” Schinazi said. “Proceed with caution.”

Long Covid might teach us how to prevent Alzheimer’s

Post author By Pragya sharma
Post date January 30, 2023
No Comments on Long Covid might teach us how to prevent Alzheimer’s

Researchers are uncovering links between viruses and brain diseases, which could point to a whole new approach to treatment.

Science is starting to uncover an unnerving fact about viruses: Some might affect our brains over the long haul. It came as a shock that SARS-CoV-2 can lead to lingering neurological problems — a post-viral syndrome we call long Covid. But the phenomenon might not be unique to this virus.

Scientists are finding links between common viruses such as influenza and brain diseases like multiple sclerosis, Parkinson’s, Alzheimer’s and ALS. Researchers are hoping that identifying a viral link might finally allow scientists to figure out what causes these mysterious, deadly ailments and develop new treatments.

A new study, published last week and summarized in Science, used a vast trove of electronic medical records to find thousands of people with neurodegenerative diseases and tease out correlations with 22 different kinds of infections. The biggest viral risk factor for dementia was encephalitis, which is an infection of the brain often caused by a mosquito or tick-borne disease. Other viruses tied to dementia included influenza, herpes zoster (shingles) and HPV.

Earlier studies had looked for specific viral links to Alzheimer’s and found correlations with herpes and some forms of HPV. And a study published last year showed that Epstein-Barr virus was necessary for developing MS. But scientists still haven’t figured out exactly what role the viruses play — whether they’re a direct trigger or have some peripheral role. Almost everyone on the planet carries Epstein-Barr virus, which causes mononucleosis, but only a tiny fraction ends up getting MS.

To better understand how viruses might be affecting the brain, I stopped by the National Institutes of Health to visit Avindra Nath, who is one of the few neurologists specializing in viruses — an interest he picked up after treating AIDS patients in the early 1980s. In 2014, he was the first neurologist to travel to Liberia to treat Ebola patients, and he said a fraction of those who recover suffer neurological symptoms similar to long Covid — especially chronic fatigue.

He told me that what really interests him are viruses that are embedded in our genetic codes — called endogenous retroviruses. They may have snuck in through a sexually transmitted virus that works itself into an embryo. These viruses are a source of genetic variation — and can add novel DNA to our genomes. Like mutations, these occasionally incur an advantage and spread through the population. About 8% of our genome is made of these embedded viruses.

Nath’s interest in these started when he was treating a patient who had both HIV and ALS, and after taking antiretroviral drugs, the ALS disappeared. A series of human and animal studies convinced Nath that ALS might sometimes be triggered by an embedded virus called HERV-K.

Normally HERV-K is active during fetal development, so it may have spread through the human population because it does something useful in utero. But after we’re born, it normally shuts off (due to external chemical switches that bind to DNA).

Sometimes, he told me, these “off switches” fail, and one of these embedded viruses can become reactivated. That failure might be part of the cause of ALS. After years of animal studies, he started preliminary human trials assessing the effects of antiviral drugs on patients with ALS. He’s now planning a placebo-controlled clinical trial for drugs that he’s shown can suppress HERV-K.

He’s also studying the kinds of viruses we catch from the outside world. He thinks viruses are more likely to trigger brain diseases indirectly — not by getting directly into neurons, but by prompting inflammation. It’s the immune system’s response that causes the problem.

He’s now studying people with neurological problems following Covid infection — something that he estimates affected about 10% of people infected before vaccines were available and a much smaller fraction today. He said that at first he was very skeptical of claims that the virus hides out in the brain, but more recent studies have made him take it seriously, especially autopsy studies done by Dan Chertow at the NIH. It might be that those residual traces of the virus are causing persistent inflammation.

It’s possible that this has always been happening to some fraction of people who pick up common viruses. It’s just that it didn’t get all that much attention before the Covid pandemic. Nath said virology and neurology were two completely different worlds, and he was unique in trying to navigate both fields at the same time.

If viruses do indeed play a role in some of our most feared and costly diseases, that could point to a whole new approach to treatment and prevention. In the future, everyone might get vaccinated against Epstein-Barr virus as a protection against MS. And it may turn out that you can reduce your odds of getting Alzheimer’s disease by getting that shingles shot and a flu shot every year. If HPV adds to the risk, it could motivate the medical community to redouble its efforts to get that vaccine to more people.

Scientists could even eventually develop a universal, variant-proof Covid vaccine that would finally prevent the risk of long Covid.

Someday, people may look back at all the expensive drugs we tested for dementia and other brain diseases and wonder how we overlooked the benefits of cheap vaccines for so long.