Tag: COVID-19

Why COVID-19 could make the overdose epidemic worse

When Alberta’s chief medical officer, Deena Hinshaw, announced special exemptions to COVID-19 regulations for group therapy in residential addiction treatment centres, it was exactly what University of Alberta addictions expert Cameron Wild was hoping to hear.

“The whole concept of recovery is in part founded on developing strong social supportive relationships,” said Wild, principal investigator with the Canadian Research Initiative on Substance Misuse in the U of A’s School of Public Health.

“The most commonly used form of treatment in programs throughout North America is founded on 12-step principles—essentially fellowship groups. These traditionally rely on in-person group meetings,” some of which have been severely limited, said Wild.

In other words, isolation and addictions simply do not mix, and Wild worries a rise in overdoses will result.

Just before COVID-19 hit, the number of deaths in Alberta as a result of fentanyl overdoses dropped to the lowest figures in three years, according to new provincial data.

In the final quarter of 2019, 109 people died from a fentanyl-related overdose, down from 158 in 2018 and 178 in 2017. But conditions caused by the pandemic could reverse that encouraging trend, said Wild.

“Any kind of retrenchment of harm reduction services has potential to negatively impact progress we were starting to see in overdose rates in the community.”

Wild and his colleagues across the country have been monitoring changes experienced by people who use drugs during the COVID-19 pandemic, especially marginalized drug users. The researchers are developing guidelines for harm reduction and addiction treatment in light of COVID-19 public health measures.

While outpatient programs now have reduced access, others are doing the best they can to continue operating with public health measures in place, said Wild.

“It’s fair to say addiction treatment has been disrupted. Clinicians across the board are concerned about maintaining critical therapeutic relationships between them and their patients, as well as the supportive social relations that go on in effective group treatment.”

More dangerous street drugs

Besides the disruption of social contact for recovering addicts, the pandemic can bring with it harmful consequences related to the illegal drug trade, said Wild. The closed Canada-U.S. border limits illegal supply, and that could lead to more adulterated and toxic drugs on the street.

“If the drug market is changing, there’s an economic incentive to maximize profit for a reduced number of drug transactions. There’s more motivation to adulterate drug supplies.

“We’re very concerned about that and the impact on drug users,” said Wild.

The pandemic has underscored the reality that many substance abusers are among the most vulnerable in society, said Wild, adding it’s hard to comply with a stay-at-home order if you don’t have a home.

“The impacts for people who are more marginalized are being felt both in drug supply chains and disruption in access to drugs because of concerns about infectious disease transmission.”

Support for substance abuse harm reduction had already been eroding before the pandemic, said Wild, especially in light of a report by the Alberta government’s Supervised Consumption Services Review Committee. It suggested supervised drug consumption sites produce increased needle debris in surrounding neighbourhoods and are a risk to public safety.

“That was the worst possible time for that to have come out,” said Wild.

“We’re really trying to promote the idea that we don’t want to exacerbate overdose death and drug-related problems by restricting harm reduction services further.”

Wild also recommends loosening restrictions on “opioid agonist” treatments such as methadone or buprenorphine to treat addiction to opioids.

“We support things like pharmacists being able to supply longer-term medication that can be more flexibly delivered,” he said.

Increased overall use of alcohol and cannabis

Wild and his colleagues have also been watching a rise in substance use—especially alcohol and cannabis—in the general population while people are sheltered at home during the pandemic.

According to a recent poll by the Canadian Centre on Substance Use and Addiction, 25 percent of Canadians aged 35–54 are drinking more at home, citing lack of a regular schedule, stress and boredom as the main reasons.

“We’re concerned about broader general population changes in substance use patterns triggered by some of the isolation and distancing issues that people are being asked to adopt.”

Wild said he hopes the experience of addicts will give us all fresh eyes to re-evaluate addictions services.

“This is a chance to look with a very sober eye at the patchwork of services that existed prior to the pandemic,” he said. “We need to reconsider several key components in how we respond to addiction.

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Preventing ‘cytokine storm’ may ease severe COVID-19 symptoms

For some COVID-19 patients, the body’s immune response may be as destructive as the virus that causes the disease. The persistent high fevers, severe respiratory distress, and lung damage seen in some critically ill patients are all signs of an immune system in overdrive.

Now, a new clinical trial will test a treatment that targets this overactive immune response, says Howard Hughes Medical Investigator Bert Vogelstein. He and his team at the Johns Hopkins University School of Medicine are currently recruiting individuals for the trial, which includes patients ages 45 to 85 at the Johns Hopkins Hospital who have COVID-19 but who aren’t on a ventilator or in the ICU.

Their treatment, a common type of prescription drug called an alpha blocker, might break a cycle of hyperinflammation before it ramps up, their findings from mouse studies and a recent analysis of medical claims data suggest.

“The approach we’re advocating involves treating people who are at high risk early in the course of the disease, when you know they’re infected but before they have severe symptoms,” says Vogelstein. If the trial’s results suggest the drug is safe and effective against COVID-19, it could potentially help many people recover safely at home and lessen the strain on hospital resources, he says.

Runaway reaction

A hyperactive immune response isn’t unique to COVID-19. People with autoimmune diseases and cancer patients receiving immunotherapy can experience similar symptoms. These responses are referred to as macrophage activation syndrome, cytokine release syndrome—or simply “cytokine storms.”

When macrophages (and some other kinds of immune cells) detect virus particles, they send out alert messages by releasing various proteins known as cytokines. Those cytokines recruit other immune cells to the scene—an inflammatory response that, in moderation, helps the body fight off a virus. But macrophages can also release other signaling molecules, called catecholamines, that amplify this response further, triggering the release of more cytokines. The result is a runaway feedback loop, like a snowball getting bigger as it barrels down a hill.

“It seems that once this process starts, there’s this inability to properly switch it off,” says Maximilian Konig, a rheumatologist at Hopkins who is helping to coordinate the trial.

Before COVID-19 hit, Vogelstein’s team was already exploring ways to ease the hyperinflammatory immune response in cancer patients treated with immunotherapy. The researchers were interested in drugs called alpha blockers, which are widely prescribed for prostate conditions and high blood pressure—and also interfere with the cell signaling that triggers cytokine storms. In theory, alpha blockers might stop a cytokine storm before it starts.

Giving mice with bacterial infections an alpha blocker lessened cytokine storms and decreased deaths, Vogelstein’s team reported in the journal Nature in 2018. And, the researchers found, the treatment didn’t seem to harm other aspects of the immune response.

Staving off the storm

As the COVID-19 pandemic escalated in the United States over the past few months and severely ill patients presented with cytokine storm symptoms, the idea of testing alpha blockers in humans has become more urgent, Vogelstein’s team recently argued in the Journal of Clinical Investigation.

To obtain approval for an alpha blocker clinical trial, Vogelstein’s team first surveyed medical claims data. They combed through records from people hospitalized for pneumonia and acute respiratory distress and analyzed whether patients’ outcomes were better if they had been taking alpha blockers for unrelated conditions. The team’s tentative conclusion: taking alpha blocker drugs correlated to a lower risk of death from respiratory distress.

On its own, that’s not strong enough evidence to prescribe the drug for a wholly new disease like COVID-19, says Susan Athey, an economist at Stanford University who collaborated with Vogelstein’s team on the claims analysis. But it helps bolster the case for the team’s clinical trial.

In the trial, COVID-19 patients will take gradually increasing doses of an alpha blocker called prazosin, sold under the brand name Minipress, over six days, says Chetan Bettegowda, a neurosurgeon at Hopkins who is helping to design and run the trials. Then, the team will evaluate whether people who received this treatment had a lower ICU admission rate or ventilator use than patients who received the standard treatment. They’ll follow each patient for 60 days, but preliminary data from the first patients could be available within weeks to months, Bettegowda says.

If the trial’s results suggest alpha blockers are safe and effective, the team hopes to run a second trial with patients who have been diagnosed with COVID-19 but are not yet hospitalized. They’re also encouraging colleagues at other hospitals to join their clinical trial efforts, to gather patient data more quickly.

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Canadian scientists testing whether cannabis can block COVID-19

Canadian scientists are testing whether compounds in marijuana can prevent coronavirus from ‘hijacking’ human cells

  • Researchers from the University of Lethbridge in Alberta, Canada looked at 400 cannabis strains and focused on about a dozen
  • They studied how extracts high in CBD, the main nonpsychoactive ingredient in, interacted with receptors coronavirus uses to attack cells
  • The extracts lowered the number of receptors the virus uses to infects cells and multiply by more than 70%
  • Here’s how to help people impacted by Covid-19

A team of Canadian scientists is testing whether or not marijuana compounds can block coronavirus infection.

Researchers at the University of Lethbridge in Alberta looked at 400 cannabis strains and focused on about a dozen that showed promise in preventing the virus from ‘hijacking’ our cells.

They say extracts of cannabidiol (CBD), the main non-psychoactive component of pot – helped lower the number of cell receptors available for coronavirus to attach to by more than 70 percent.  

However, the team says people should not rush out and by cannabis products and that clinical trials are needed to confirm the results. 

Researchers from the University of Lethbridge in Alberta, Canada looked at 400 cannabis strains and focused on about a dozen (file image)

They studied how extracts high in CBD, the main nonpsychoactive ingredient in, interacted with receptors coronavirus uses to attack cells. Pictured: A nurse suctions the lungs of a COVID-19 patient at St. Joseph’s Hospital in Yonkers, NY, April 20

For the study, published the pre-peer reviewed journal Preprints, the scientists partnered with Pathway Rx, a cannabis therapy research company, and Swysh Inc, a cannabinoid-based research company.

The team created artificial 3D human models of oral, airway and intestinal tissues with a sample of high CBD extracts from Cannabis Sativa plants. 

The extracts were low in THC, the main psychoactive ingredient in marijuana.   

Next, researchers tested the effect the extracts had on angiotensin-converting enzyme 2 (ACE2), the receptors required for the virus to enter human cells. 

Results showed that the extracts helped reduce the number of receptors that are the  ‘gateway’ for the coronavirus to ‘hijack’ host cells.

‘A number of them have reduced the number of [virus] receptors by 73 percent, the chance of it getting in is much lower,’ lead researchers Dr Igor Kovalchuk, CEO of Pathway Rx, told The Calgary Herald.

‘If they can reduce the number of receptors, there’s much less chance of getting infected.’ 

They also looked at other receptors such as TMPRSS2, which allows the virus to invade cells more easily and multiply quickly.   

‘Imagine a cell being a large building,’ Kovalchuk told CTV News. 

‘Cannabinoids decrease the number of doors in the building by, say, 70 percent, so it means the level of entry will be restricted. So, therefore, you have more chance to fight it.’  

However, the team says this does not mean that people should go out and buy marijuana products as prophylactics. 

Cannabis and CBD products that are currently on the market are not designed to treat or prevent infection from COVID-19. Therefore, clinical trials are needed. 

‘Given the current dire and rapidly developing epidemiological situation, every possible therapeutic opportunity and avenue needs to be considered,’ Kovalchuk said in an April press release. 

‘Our research team is actively pursuing partnerships to conduct clinical trials.’ 

If trials proves to be successful, he says the CBD strains may be used as mouth wash, gargle, inhalants or gel caps,

‘It would be cheaper for people and have a lot less side-effects,’ Kovalchuk told The Herald.  

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Experts share what you need to know about COVID-19 as states reopen

As governments begin easing restrictions that were put in place to slow the spread of COVID-19, public health and infectious disease experts from The University of Toledo are offering insight into what you need to know about the novel coronavirus, how to protect yourself, and how to protect others.

The virus is still here. We have to act accordingly.

While the number of newly confirmed cases in many states—including Ohio and Michigan—appears to have peaked, the virus hasn’t gone away or become less dangerous.

“We all yearn for the way life was in the pre-pandemic days, and we are going to get there, but this is going to be the situation for a while,” said Dr. Brian Fink, an epidemiologist and professor of public health. “We have to respect that and continue taking the same precautions.”

Though it’s tempting to see businesses reopening and leisure activities resuming and think the threat of the virus is behind us, Fink said the reality is the novel coronavirus is still spreading across the United States.

Take steps to protect your own health and the health of others.

“People do still need to be careful,” said Dr. Jennifer Hanrahan, an associate professor of medicine and chief of infectious diseases at The University of Toledo Medical Center. “One of the worst things that people could do at this point is go out and resume their normal behavior. We would certainly have a resurgence.”

Diligent handwashing, avoiding touching your nose and mouth, staying home if you’re sick, and social distancing should all continue, UToledo experts said. Individuals who are older or high-risk because of underlying health conditions should be more careful.

Fink said there are simple things you can do. For example, when shopping, avoid picking up an item and then putting it back, and keep your distance from other shoppers. It’s also important, he said, to make decisions based not only on your own risk, but the risk of those around you.

“It’s difficult. We all want to see our friends and family,” he said. “We just have to be patient. If we’re patient and we follow the guidelines as best as possible, we’ll be back to normal sooner rather than later, even though that’s going to take time,” Fink said.

Wearing a cloth face covering does make a difference. Wear one if you’re around others.

The shifting guidance from public health officials on mask usage has caused confusion and pushback, but Hanrahan encourages people to wear a simple mask or cloth face covering when around other people.

“Two things are happening. The person wearing the mask is reducing the amount of stuff they’re putting in the environment, and they’re also reducing the amount they breath in,” she said. “It’s not going to prevent everything, but there is some protection.”

Hanrahan said face coverings, combined with continued social distancing and new measures being implemented by businesses, such as clear barriers at cash registers and limits on the number of people allowed in one place at one time, will reduce the overall risk.

Fink said its important people recognize things such as mask recommendations or requirements are being done for the benefit of everyone, not to target specific individuals.

“I always tell my students there are going to be people in the population who aren’t going to be happy. We’re seeing that,” Fink said. “But we’re putting these guidelines in place for the health and well-being of everyone.”

Individuals with pre-existing health conditions are most vulnerable, but no one is immune to the illness.

As physicians and researchers learn more about COVID-19, there are also some troubling discoveries. Along with older Americans and those who have diabetes, compromised immune systems and chronic lung diseases, Hanrahan said doctors are finding people with morbid obesity and high blood pressure are at high risk of complications.

“Hypertension alone would not necessarily be thought of as a potential problem with a viral infection, but it actually is,” she said. “For people who have those conditions or other underlying medical conditions, they really need to think about whether it makes sense for them to go to the grocery store or be around a lot of other people.”

Additionally, there are an increasing number of reports of children developing a severe inflammatory response linked to COVID-19, even when they weren’t previously sick.

“COVID-19 is not just affecting people who are at high risk for complications,” Hanrahan said.

Scientists and physicians have learned a lot about the virus, but we’re still a long way from having routine treatments or a vaccine.

The coronavirus that causes COVID-19 was completely unknown before it began spreading among people early this year. Since then, there has been a tremendous amount of research both in how the virus spreads and potential ways to treat or prevent it.

“We have learned a lot about this virus,” Hanrahan said. “Most of the spread really is by droplets, typically within a few feet of the person. The social isolation part, keeping six feet of distance, that does actually make a difference.”

Doctors also have a better idea how to manage the virus, and hundreds of drugs are being examined to potentially fight COVID-19 and its effects. Some, including the antiviral drug remdesivir, are showing promising early results. Progress also is being made in vaccine development.

However, while there is reason for hope, Hanrahan said it will take time to get any of these therapeutics in the quantities needed. Gilead Sciences, which makes remdesivir, anticipates making a million courses of that drug globally by December.

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Treatment guidance for lung cancer patients during the COVID-19 pandemic

Lung cancer patients are at heightened risk for COVID-19 and the reported high mortality rate among lung cancer patients with COVID-19 has given pause to oncologists who are faced with patients with not one, but two severe, life-threatening diseases.

To help oncologists address the many challenges COVID-19-positive lung cancer patients present, a team of global lung cancer specialists this week published a review of lung cancer treatments for patients with COVID-19 in the current issue of the Journal of Thoracic Oncology, the official journal of the International Association for the Study of Lung Cancer (IASLC).

“The purpose of this manuscript is to present a practical multidisciplinary and international overview to assist in treatment for lung cancer patients during this pandemic, with the caveat that evidence is lacking in many areas,” said lead author Chandra Belani, MD, chief science officer for the IASLC, Professor of Medicine and Oncology at the Penn State College of Medicine and Penn State Cancer Institute.

As a group, lung cancer patients tend to be older and have an increased risk of relative immunosuppression from the underlying malignancy and from anti-cancer treatments. Furthermore, patients with lung cancer may have additional comorbidities, including a history of smoking and pre-existing lung disease.

“A major consideration in the delivery of cancer care during the pandemic is to balance the risk of patient exposure and infection with the need to provide effective cancer treatment,” Belani writes.

The rapid onset of the COVID-19 infection requires careful consideration of urgent decisions to treat lung cancer. Treatment decisions balancing the risk of exposure with effective care require close multidisciplinary discussions and thorough deliberation between caregivers and patients. The duration and severity of the COVID-19 pandemic are unclear, and treatment delay alone will be insufficient to provide optimal treatment to cancer patients.

“In combination with determining a treatment path for lung cancer, physicians should educate patients to help them prevent further spread of COVID-19 according to WHO and CDC guidelines,” Belani urged colleagues.

COVID-19 complicates cancer care further by forcing patients into self-isolation to protect themselves, other patients, providers, and family members.

“Self-isolation goes against best practices for treating cancer patients, which often calls for joining support groups, reaching out to loved ones and family members for assistance and remaining active,” Belani said. “The decision regarding immediate vs. delayed treatment during the COVID-19 pandemic should balance the delay of treatment in the presence of existing co-morbidities vs. the possible harm from COVID-19.”

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Primary care key to protecting Australians from COVID-19

Australia’s GP clinics, pharmacies and other primary care services are key to protecting our most vulnerable people against COVID-19, according to new research led by experts at the Australian National University (ANU).

Professor Michael Kidd AM, who is Professor of Primary Care Reform at ANU, as well as Deputy Chief Medical Officer with the Australian Government Department of Health, says Australia’s primary care response to COVID-19 has been guided by lessons learnt from previous pandemics.

“With previous pandemics—for example, SARS—primary care wasn’t heavily involved in either the planning or response,” Professor Kidd said.

“But we now know the importance of engaging early and effectively with primary care, to protect the community, especially our most vulnerable members, and our health workers.”

According to Professor Kidd, one of the top priorities is making sure our primary care system is able to not only manage COVID-19, but other new and ongoing medical conditions.

“That’s another lesson learnt from previous pandemics. There’s a risk of more people dying from not having regular access to their normal health care services,” he said.

“People might be afraid to go to a general practice or emergency department, or to go out and get their prescriptions filled. People with chronic health conditions or mental health concerns might avoid regular appointments.”

The other big change has been the transition to telehealth services using telephone and videophone consultations.

“Most GPs already use phone calls to communicate with their patients. This is a major change to the model of care delivery and the first time we’ve seen Medicare funding for whole of population telehealth services in Australia,” Professor Kidd said.

“This means people don’t have to leave their homes during the pandemic to attend appointments, and it also protects doctors, nurses and other health care staff. It is important that face to face consultations still remain available whenever needed.”

ANU researchers are working with health officials to document the national primary care COVID-19 response.

“This will be invaluable in guiding our nation’s response to future pandemics and other serious public health emergencies,” Professor Kidd said.

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Coronavirus: SARS-CoV-2-Evolution on the basis of genetic mutations to understand – Naturopathy naturopathy specialist portal

Better understanding of SARS-CoV-2 mutations to new drugs?

In the analysis of the virus genomes of people with COVID-19 nearly 200 recurring genetic mutations in the Virus were identified, what information on effective drugs and vaccine goals.

In the current study of the University College London are important patterns of diversity of SARS were characterized CoV-2 virus genome, which could contribute to the development of medicinal products or an effective treatment. The results of the study were published in the English journal “Infection, Genetics and Evolution”.

Patterns of diversity of the SARS-CoV-2 virus genome have been characterized for the first time

Through the analysis of the virus genomes of over 7,500 with Covid-19 infected individuals were characterized by the pattern of the diversity of the SARS-CoV-2 virus genome. The study identified 198 recurrent genetic mutations in the Coronavirus show how it adapts possibly to its human hosts, and more developed.

Results indicate a global Transmission to the beginning of the epidemic

The researchers found that a large proportion of the global genetic diversity of SARS-CoV-2 occurs in all heavily affected countries, which suggests a comprehensive global Transmission already at the beginning of the epidemic. In addition, this indicates the Absence of individual patient-zero cases in most of the countries.

Study shows how the Virus adapts

The results of the investigation show that the Virus appeared at the end of the year 2019, before it quickly spread over the whole world. 198 the mutations that have apparently occurred independently more than once, give an indication of how the Virus adapts.

SARS-CoV-2 mutated to a more deadly Virus?

Viruses mutate in a natural way. Mutations are neither good nor bad, but rather indicate how fast or slow a Virus adapts. Up to now, can not be said whether SARS-CoV-2 will be in the future more or less deadly and contagious, report the researchers.

Better targets for treatment identified

The small genetic changes, or mutations, which were identified, were not evenly distributed across the viral genome. Some parts of the genome showed very few mutations, explain the researchers. These unchanging parts of the Virus might be better targets for the development of drugs and vaccines.

Medicines can be due to Mutation ineffective

A major challenge in the fight against a virus is to a vaccine or a drug might be effective if the Virus has mutated. To focus research on parts of the Virus that mutate less likely to be increased to develop the likelihood of drugs that are effective in the long run. There is a need to develop drugs and vaccines that can not be circumvented by the Virus easily, explain the researchers.

When did the Virus for the first time in humans?

The results complement a growing number of Evidence that SARS-CoV-2 viruses have from the end of 2019 from a common ancestor, suggesting that this was the time the Virus from a previous animal host in the people jumped. This means that it is highly unlikely that the CORVID-19-causing was the end of the Virus long before its first detection in humans in circulation, reports the researchers.

Analysis of such an exceptionally high number of virus genomes is extremely advantageous

To be In the first months of the pandemic in the position to analyze such an extraordinary number of virus genomes, it could be for the development of drugs of inestimable value, adds the research group. This shows how far the genome research has come in the last decade. We all benefit from the enormous efforts of hundreds of researchers worldwide, the virus genome sequenced and available online have been made, report the researchers. (as)

Immunity of recovered COVID-19 patients could cut risk of expanding economic activity

While attention remains focused on the number of COVID-19 deaths and new cases, a separate statistic—the number of recovered patients—may be equally important to the goal of minimizing the pandemic’s infection rate as shelter-in-place orders are lifted.

The presumed immunity of those who have recovered from the infection could allow them to safely substitute for susceptible people in certain high-contact occupations such as healthcare. Dubbed “shield immunity,” the anticipated protection against short-term reinfection could allow recovered patients to expand their interactions with infected and susceptible people, potentially reducing overall transmission rates when interactions are permitted to expand.

New modeling of the virus’ behavior suggests that an intervention strategy based on shield immunity could reduce the risk of allowing the higher levels of human interaction needed to support expanded economic activity. The number of Americans infected by the novel coronavirus is likely much higher than what has been officially reported, and that could be good news for efforts to utilize their presumed immunity to protect the larger community.

However, there are two important caveats to the strategy. The first is that the duration of immunity to reinfection by SARS-CoV-2 remains unknown; however, individuals who survived infections by related viral infections, like SARS, had persistent antibodies for approximately two years—and those who survived infection to MERS had evidence of immunity for approximately three years. The second issue is that determining on a broad scale who has antibodies that may protect them from the coronavirus will require a level of reliable serological testing not yet available in the United States.

“Our model describes ways in which serological tests used to identify individuals who have been infected by and recovered from COVID-19 could help both reduce future transmission and foster increased economic engagement,” said Joshua Weitz, professor in the School of Biological Sciences and founding director of the Interdisciplinary Ph.D. in Quantitative Biosciences at the Georgia Institute of Technology. “The idea is to think in advance about how identifying recovered individuals could help serve the collective good, using information collected on neutralizing antibodies in new ways.”

A paper describing the modeling behind the concept of shield immunity was published May 7 in the journal Nature Medicine by a team of researchers from Georgia Tech, Princeton University and McMaster University. The researchers studied the potential impacts of presumed immunity among recovered persons using a computational model of COVID-19 epidemiological dynamics, building upon a SEIR (susceptible-exposed-infectious-recovered) framework.

In a population of 10 million citizens, for example, the model predicts that in a worst-case transmission scenario, implementation of an intermediate shielding strategy could help reduce deaths from 71,000 to 58,000, while an enhanced shielding plan could cut deaths from 71,000 to 20,000. The model also suggests that shielding could enhance the effects of social distancing strategies that may remain in place once higher levels of economic activity resume.

Identification of individuals who have protective antibodies against the novel coronavirus has begun only recently. Antibody tests are not 100% specific, implying that tests can lead to false positives. However, targeted use of antibody testing in groups with elevated exposure will lead to increases in positive predictive value, even with imperfect tests. The serological antibody test differs from widespread polymerase chain reaction (PCR) testing being done to determine whether people are actively infected with the virus.

Among healthcare professionals, serological testing could identify recovered individuals who might then be able to interact with patients with reduced concern for infection. Other recovered individuals could be used to help reduce transmission risk in nursing homes, the food service industry, emergency medical services, grocery stores, retailing and other essential operations. Across society, the relatively small number of individuals with immunity could substitute for people whose immunity status isn’t known; reducing transmission risk both for recovered individuals and those who remain immunologically naive.

“We want to think about serology as an intervention,” Weitz said. “Finding out who is immune to the coronavirus could make a big difference in trying to reduce the risk to people who would be vulnerable by interacting with someone who could pass on the disease.”

Serological testing to identify those with immunity might begin with healthcare workers, who may be more likely to have been infected by the coronavirus because of their exposure to infected persons, Weitz said. Because so many infections do not produce the distinctive COVID-19 symptoms, it’s likely that many people have recovered from the illness without knowing they’ve had had it, potentially expanding the pool of recovered persons.

“There may be a deeper pool of individuals who can help within their own fields and other fields of specialization to reduce transmission,” Weitz said. “The reality is that people within high-contact jobs probably are likely to have a higher incidence of infection than other groups.”

But using antibody information about individuals would create potential privacy issues, and require that those individuals make informed decisions about accepting additional risks for the greater good of the community.

“What this model says is that if we could identify individuals who are immune, there is a chance that some individuals would not have to reduce their level of interaction with others because that interaction would be less risky,” he added. “Rather than trying to keep reducing interactions, which is helpful for reducing transmission but bad for what it does for the economy, we might be able to maintain interactions while reducing the risk, combined with other mitigation approaches.”

Ultimately, addressing the pandemic will require development and mass production of a vaccine that could boost immunity levels beyond 60 percent in the general population. Until that is available, Weitz believes that shield immunity could become part of the approach to the challenge.

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