Unraveling the Mysterious Mutations That Make Delta the Most Transmissible Covid Virus Yet

Unraveling the Mysterious Mutations That Make Delta the Most Transmissible Covid Virus Yet

Upon first inspection, the mutations in the highly contagious delta covid variant don’t look that worrisome.

For starters, delta has fewer genetic changes than earlier versions of the coronavirus.

“When people saw that the epidemic in India was driven by delta, they did not suspect it would be so bad or overtake other variants,” said Trevor Bedford, an evolutionary biologist at the Fred Hutchinson Cancer Research Center.

Originally published in Kaiser Health News.

But those expectations were wrong.

Delta has kept some of the most successful mutations found in earlier variants, but also contains new genetic changes that enable it to spread twice as fast.

Delta is more dangerous in many ways. It has an incubation period of four days, rather than six, making people contagious sooner. When the pandemic began, people spread the original coronavirus to an average of two or three people. Today, people infected with delta infect six people, on average.

As of this week, the delta variant had caused at least 92% of the new infections in the United States, according to covariants.org, a research firm in Bern, Switzerland.

Although delta isn’t necessarily any more lethal than other variants, it can kill huge numbers of people simply because it infects so many more, said Dr. Eric Topol, founder and director of the Scripps Research Translational Institute.

Scientists have sequenced delta’s mutations but are still trying to understand their significance, said Angela Rasmussen, a virologist at the University of Saskatchewan’s Vaccine and Infectious Disease Organization. “When we see the same mutations appearing repeatedly and independently, that suggests they’re important,” Rasmussen said.

Scientists have the best understanding of mutations on the so-called spike protein — which sticks out from the surface of the virus like a club — and which have been studied the most intensely because of its serious ramifications, Rasmussen said. The coronavirus uses the spike protein to enter human cells, and changes in the spike can help the virus evade antibodies.

Scientists believe one of the most important areas of the spike is the receptor-binding domain, the specific part of the protein that allows the virus to latch onto a receptor on the surface of our cells, said Vaughn Cooper, a professor of microbiology and molecular genetics at the University of Pittsburgh. Receptors are like sockets or docking stations that allow proteins to interact with the cell. Once the virus gains entry to the cell, it can cause havoc, hijacking the cell’s genetic machinery and turning it into a virus-making factory.

Delta’s Worrisome Mix

Delta’s rapid spread is particularly surprising given it lacks two mutations that made earlier variants so scary.

Delta doesn’t have the N501Y spike mutation found in the alpha, beta and gamma variants, which enabled them to invade cells more successfully than the original virus. That mutation changed one amino acid — a building block of proteins — in the receptor-binding domain.

Delta also lacks the E484K mutation, which has made the gamma variant so worrisome. This genetic change, sometimes called “Eek,” allows the virus to spread even among vaccinated people.

(Scientists use the Greek alphabet to name variants of concern.)

“The ‘D’ in delta stands for ‘different’ and a ‘detour’ to a different genomic mutation path,” Topol said. “But it doesn’t mean ‘doom,’” he said, noting that existing covid vaccines remain mostly effective against the delta variant.

Vaccines protect people from covid by providing them with antibodies that attach themselves to the spike protein, preventing the virus from entering cells. By dramatically reducing the number of viruses that enter cells, vaccines can prevent people from developing severe disease and make them less infectious to others.

Delta does share mutations with other successful variants. Like all the identified variants in circulation, delta contains a spike mutation called D614G, sometimes known as “Doug,” which became ubiquitous last year.

Scientists think Doug increases the density of spike protein on the surface of viral particles and makes it easier for the virus to enter cells.

Delta also has a spike mutation called P681R, which closely resembles a mutation in the alpha variant that appears to produce higher viral loads in patients, Cooper said. People infected with delta have 1,000 times more virus in their respiratory tract, making them more likely to spread the virus when they sneeze, cough or talk.

The P681R mutation, also found in the kappa variant, is located at the beginning of a part of the genome called the furin cleavage site, Cooper said.

Furin is a naturally occurring human enzyme that gets hijacked by the coronavirus, which uses it to slice the spike protein into the optimal shape for entering the cell, Rasmussen said. The new mutation makes that sculpting more efficient, Rasmussen said.

Another delta mutation — also found in kappa and epsilon — is called L452R.Experiments suggest this mutation, which also affects the receptor-binding domain, acts to prevent antibodies from neutralizing the virus, Cooper said.

These mutations appear to be more formidable as a team than alone.

The genetic changes “are certainly doing something, but why that combination makes the delta variant more fit is not entirely obvious,” Bedford said. “Putting them together seems to matter.”

Delta also has developed genetic changes not seen in other variants.

One such spike mutation is called D950N. “This might be unique,” Cooper said. “We don’t see that anywhere else.”

The D950N mutation is different than other mutations because it’s located outside the receptor-binding domain in an area of the coronavirus genome that helps the virus fuse with human cells, Cooper said. Fusing with human cells allows the coronavirus to dump its genetic material into those cells.

This mutation could affect which types of cells the virus infects, potentially allowing it to harm different organs and tissues. Mutations in this region are also associated with higher viral loads, Cooper said.

Delta also contains mutations in a part of the spike protein called the N-terminal domain, which provides a “supersite” for antibodies to latch onto the virus and prevent it from entering cells, said Dr. Hana Akselrod, an infectious diseases specialist at the George Washington University School of Medicine & Health Sciences.

Mutations in this region make monoclonal antibodies less effective in treating covid and increases the delta variant’s ability to escape vaccine-generated antibodies, Akselrod said. That may explain why vaccinated people are slightly more likely to become infected with delta, causing mostly mild illness but allowing them to transmit the virus.

Delta’s Future Course

Scientists say it’s impossible to predict exactly how delta will behave in the future, although Topol said, “It’s going to get worse.”

Topol noted that delta outbreaks tend to last 10 to 12 weeks, as the virus “burns through” susceptible populations.

If the United States continues to follow a pattern seen in the United Kingdom and the Netherlands, infections could rise from the current seven-day moving average of 42,000 cases to 250,000 a day. Yet Topol said the United States is unlikely to suffer the high death rates seen in India, Tunisia and Indonesia because nearly half the population here is fully vaccinated.

While some studies have concluded that the Johnson & Johnson vaccine stimulates strong and persistent antibodies against delta, a new report found that antibodies elicited by one shot may not be enough to neutralize delta. Authors of that study, from the New York University Grossman School of Medicine, suggested a second dose may be needed.

Two doses of the Pfizer-BioNTech vaccine protect 94% of people from any symptomatic infection by the alpha variant, compared with 88% against the delta variant, according to a new study in the New England Journal of Medicine. Two doses of the AstraZeneca vaccine protect 75% of people from alpha and 67% from delta.

Cooper said covid vaccines offer remarkably good protection. “I will always celebrate these vaccines as the scientific achievements of my lifetime,” he said.

The best way to slow down the evolution of variants is to share vaccines with the world, vaccinating as many people as possible, Bedford said. Because viruses undergo genetic changes only when they spread from one host to another, stopping transmission denies them a chance to mutate.

Whether the coronavirus evolves more deadly variants “is totally in our hands,” Cooper said. “If the number of infections remains high, it’s going to continue to evolve.”

By failing to contain the virus through vaccination, wearing masks and avoiding crowds, people are allowing the coronavirus to morph into increasingly dangerous forms, said Dr. William Haseltine, a former Harvard Medical School professor who helped design treatments for HIV/AIDS.

“It’s getting better, and we’re making it better,” he said. “Having half the population vaccinated and half unvaccinated and unprotected — that is the exact experiment I would design if I were a devil and trying to design a vaccine-busting virus.”

ANA Supports Updated CDC Masking Guidance

ANA Supports Updated CDC Masking Guidance

SILVER SPRING, MD – The American Nurses Association (ANA) underscores the urgency to follow the science and evidence to swiftly mitigate the impact of the highly transmissible and contagious Delta variant that is stalling our nation’s efforts to recover from the COVID-19 pandemic. ANA continues to implore all health care professionals and the public to follow the science, adhere to the latest guidance of public health officials, and get vaccinated against COVID-19. 

“COVID-19 is a formidable opponent,” said ANA President Ernest Grant, PhD, RN, FAAN. “However, we have tools in our arsenal to defeat it. Vaccines are effective in preventing the uptick of new infections and hospitalizations daily in areas of the country experiencing surges from the Delta variant. The normalcy that we all desperately seek can be achieved if enough people get vaccinated against COVID-19.”

ANA has and continues to strongly advocate that the public practice the precautions recommended by public health officials to prevent the spread of COVID-19 until the U.S. population has been broadly immunized against the virus. Americans who remain apprehensive about getting vaccinated should seek credible information from a trusted health care professional and ask family members and community leaders who have been vaccinated about their experience. 

ANA has consistently called for all nurses and health care workers to be vaccinated against COVID-19 according to current recommendations for immunization of health care professionals and supports the mandate of vaccinations. ANA provides nurses education and resources to guide their understanding and consideration of COVID-19 vaccines. It is critical that health care professionals model the same health maintenance and prevention measures as their patients – this protects health care teams, colleagues, patients, and the community.

“As a nation, we must collectively stay the course and do our part to stop the spread. Vaccination is a significant public health victory and a scientifically proven strategy to slow the spread of COVID-19 and prevent the loss of more American lives,” said Dr. Grant.


About the American Nurses AssociationThe American Nurses Association (ANA) is the premier organization representing the interests of the nation’s 4.2 million registered nurses. ANA advances the profession by fostering high standards of nursing practice, promoting a safe and ethical work environment, bolstering the health and wellness of nurses, and advocating on health care issues that affect nurses and the public. ANA is at the forefront of improving the quality of health care for all. For more information, visit www.nursingworld.org

This Might Hurt a Bit: the Chronic Nursing Shortage is Now Acute

This Might Hurt a Bit: the Chronic Nursing Shortage is Now Acute

If the nursing shortage is bad now, chances are it’s going to get much worse. 

“Hospitals were having difficulty finding nurses to fill positions before the pandemic,” notes Kendra McMillan, MPH, RN, Senior Policy Advisor for Nursing Practice and Work Environment at the American Nurses Association (ANA). “In fact, according to the US Bureau of Labor Statistics, 175,900 RN openings were projected each year through 2029, when we factor in nurses leaving the workforce for reasons such aretirement. Unfortunately, the pandemic’s demand on the healthcare system has further exacerbated a long-standing projection that has burdened our nursing workforce.” 

Kendra McMillan, MPH, RN, ANA Senior Policy Advisor for Nursing Practice and Work Environment
Kendra McMillan, MPH, RN, ANA Senior Policy Advisor for Nursing Practice and Work Environment

Doctors and nurses are overworked, thanks to chronic staffing shortages made worse by a pandemic that drove thousands from the field, writes The New York Times. On the West Coast,  “the nursing shortage affecting the whole nation is impacting the Northwest region as well,” according to an article in The Bulletin (headquartered in Bend, OR), quoting a Kaiser spokeswoman. 

“Finding experienced nurses has always been a challenge in Southern California,” according to Cherie Fox, RN, MSN, CCRN-K, Executive Director Acute Care Services, Providence Mission Hospital, Mission Viejo, California.  “Following the COVID-19 pandemic, we are seeing nurses retire, move out of the area, and reduce hours, all of which has amplified our staffing challenge just a bit.” Fox led the initial team that opened the COVID ICU and telemetry units during the pandemic.  She recently coauthored a paper in Critical Care Nurse detailing Providence Mission Hospital’s COVID response.  

And a recent study found that nurses are reporting large declines in their mental health. More alarming, nurses, especially those who are younger, are feeling less committed to the profession. 

Multiple factors, coupled with the pandemic, are influencing the nursing shortage, according to McMillan. These include burnout, work environment stress, workplace violence, an aging workforce that is retiring, and an aging population with comorbidities. 

Multiple Solutions 

To address the growing crisis, hospitals are pursuing multiple solutions, including hiring travel nurses. “I’ve talked to several emergency departments across the country that are having those issues where they’re having to have temporary nurses come in to the emergency department,” says Ron Kraus, MSN, RN, EMT, CEN, TCRN, ACNS-BC, Emergency Nurses Association president and Emergency Department Clinical Nurse Specialist at Indiana University Health Methodist Hospital.  

ENA President Ron Kraus
ENA President Ron Kraus, MSN, RN, EMT, CEN, TCRN, ACNS-BC

Providence Mission Hospital has also made use of travel nurses and offers a referral bonus to current caregivers. Fox notes that nurses are taking time off while others are getting ready for vacations. “While the time off is needed and approved, it does add further to dependence on traveling nurses.” 

“Hiring bonuses, tuition reimbursement, and loan repayment are examples of incentives offered to nurses to boost recruitment and retention efforts,” notes the ANA’s McMillan. But, she adds, hiring bonuses don’t support efforts to retain nurses who are already employed in the organization. 

“Nurses are facing longer shifts and are working more consecutive shifts to meet the persistent demands on our healthcare system” notes McMillan. The nurses who remain are burned out physically, mentally, and emotionally.” 

The ENA, notes Kraus, is focusing on helping hospitals create a healthy work environment. Having a healthy work environment that empowers nurses, while supporting their needs, helps to overcome fatigue and moral distress, notes Fox. 

Calling it an “amazing profession,” Kraus would encourage individuals to enter the profession.  
For a lot of us, it was very trying, but it’s a calling,” he says.  

ANA Supports OSHA Emergency Standard to Protect Nurses from Covid

ANA Supports OSHA Emergency Standard to Protect Nurses from Covid

SILVER SPRING, MD—The American Nurses Association (ANA) advocated for and supports the Occupational Safety and Health Administration (OSHA) Emergency Temporary Standard (ETS) that requires employers to better protect nurses from COVID-19 hazards in the work environment. 

This standard, published in the July 6th Federal Register,  recognizes that nurses must have the most stringent levels of safety protections to provide the highest quality care to their patients. Critically, the ETS requires that employers provide better protections for nurses by developing and implementing plans to identify and control COVID-19 hazards in the workplace. Nurses who care directly for patients with confirmed or suspected COVID-19 must also be protected by approved respirators, which include single-use N95 respirators, elastomeric respirators, and powered air-purifying respirators (PAPR). Employers must also provide gloves, gowns, and eye protection. This requirement applies regardless of the nurses’ vaccination status. Employers are also required to screen health care personnel daily for COVID-19, provide COVID-19 tests at no charge to the employee, and to support employees to receive COVID-19 vaccinations.

The ETS also empowers nurses to advocate for meaningful safety improvements during the duration of the emergency standard, as well as providing whistleblower protections for employees who raise safety concerns.

“While ANA is pleased that OSHA took the rare step to issue this new emergency standard, it is long overdue as nurses have been—and continue to be—at high risk for exposure to COVID-19.” said ANA President Ernest J. Grant, PhD, RN, FAAN. “ANA has been calling for specific safety protections from COVID-19 since the start of the coronavirus pandemic and while this ETS is beneficial, it is not a replacement for a permanent standard with strong respiratory protections, which remains a necessity. According to OSHA’s own materials, by the end of May 2021 nearly 492,000 health care personnel had contracted COVID-19 and more than 1,600 had died. More must be done to protect our nation’s nurses and frontline health care workers from the ravages of this pandemic.”

comprehensive survey in February 2021 by the American Nurses Foundation (the Foundation) found that 74% of respondents said that consistent and better executed national health policies and public intervention plans will better prepare for future crises or pandemics. Nurses understand the critical role the federal government plays in ensuring their safety. They also know that this pandemic is not over, and that the future will inevitably bring new pandemics and public health crises. Nurseslives must not be endangered because policymakers have failed to take actions to adequately prepare. ANA is committed to protecting nurses and frontline health care workers.  It  will engage with OSHA on the implementation and enforcement of this ETS and continue to advocate for permanent protections from infectious agents in health care delivery.

Except for a few requirements, OSHA expects employers to comply with the ETS as of July 6, 2021, and nurses are able to comment on it through July 21, 2021. ANA encourages nurses and health care personnel to learn about the new requirements and to understand how to report violations, by visiting OSHA’s website. ANA members can also access our Policy Brief on the ETS here.

NNU to CDC: Reinstate Universal Masking

NNU to CDC: Reinstate Universal Masking

National Nurses United (NNU), the largest union of registered nurses, sent a letter to the Centers for Disease Control and Prevention (CDC) on July 12, urging the agency to update its Covid-19 guidance and reinstate “the recommendation for everyone to wear masks in public or in physical proximity to others outside their own household.”
“NNU strongly urges the CDC to reinstate universal masking, irrespective of vaccination status, to help reduce the spread of the virus, especially from infected individuals who do not have any symptoms,” wrote NNU Executive Director Bonnie Castillo, RN, in the letter. “SARS-CoV-2, the virus that causes Covid-19 disease, spreads easily from person to person via aerosol transmission when an infected person breathes, speaks, coughs, or sneezes.”
The letter noted that the “Covid-19 pandemic is far from over,” with a 16 percent increase in daily new cases over the previous week and more than 40 states seeing an increase in daily new cases over the previous two weeks as well as 25 states seeing an increase in hospitalizations.
NNU stated that the rise in cases is not surprising due to “the rapid reopening of many states and the removal of public health measures, including the CDC’s May 13, 2021 guidance update that told vaccinated individuals they no longer needed to wear masks, observe physical distancing, avoid crowds, or get tested or isolate after an exposure, within only a few exceptions.”  
Unfortunately, the “CDC’s guidance failed to account for the possibility—which preliminary data from the United Kingdom and Israel now indicates is likely—of infection and transmission of the virus, especially variants of concern, by fully vaccinated individuals,” the letter continued. The Delta SARS-CoV-2 variant is already dominant in the United States.
The CDC’s May 13 guidance “also failed to protect medically vulnerable patients, children, and infants who cannot be vaccinated, and immunocompromised individuals for whom vaccines may be less effective.” Asymptomatic or pre-symptomatic infected people “can spread infectious SARS-CoV-2 aerosols during breathing and speaking, without coughing or other respiratory symptoms,” the letter noted.
Covid-19 vaccines are an important public health tool, but multiple measures are necessary to protect public health, as NNU noted in a May 17, 2021 scientific brief. However, only 48 percent of the total U.S. population have been fully vaccinated as of July 11, 2021, according to the CDC. The vaccines are effective at preventing serious illness and death from the virus for vaccinated people. However, no vaccine is 100 percent effective and the emergence and spread of variants of concern may reduce vaccine effectiveness.
“Masks are a simple and effective tool, especially when used in combination with other measures to reduce the risk of Covid-19,” noted Castillo in the letter. On June 25, 2021, in response to the spread of the Delta variant, the World Health Organization urged fully vaccinated people to wear masks.

In the letter, NNU also called on the CDC to:

  • update health care infection control and other Covid-19 guidance to fully recognize aerosol transmission,
  • require tracking and transparent reporting of Covid infections among health care workers and other essential workers, and
  • track infections in people who are fully vaccinated, including mild and asymptomatic infections.
Four Ways COVID-19 Changed the Role of the Psychiatric Mental Health Nurse Practitioner

Four Ways COVID-19 Changed the Role of the Psychiatric Mental Health Nurse Practitioner

Psychiatric Mental Health Nurse Practitioners (PMHNPs) are board-certified advanced practice nurses who diagnose and treat mental health and substance abuse issues. PMHNPs work in outpatient and inpatient settings, providing assessment, therapy, and medications. PMHNPs are critical in any disaster, providing emergent mental health care and psychosocial support to new patients and continuing outreach and support to established patients. Most recently, the COVID-19 pandemic has initiated a global mental health crisis.

The pandemic mental health crisis is unique in its influence on millions impacted by isolation, job loss, financial strain, and grief. Approximately half of Americans feel that the pandemic harmed their mental health. In addition, millions of healthcare workers that cared for COVID patients are expected to suffer mental health issues for up to a year after the pandemic ends. This increase in mental health issues post-COVID will create an additional cyclical mental health strain on the healthcare system.

To meet the increasing and expected mental health and substance abuse issues, the practice landscape for PMHNPs has changed. Recognition of emergent and forecasted needs combined with a national shortage of psychiatrists has led to dramatic changes in the PMHNP role.

1.   Expanded scope of practice

Many states aligned with the Centers for Medicare and Medicaid Services (CMS) to expand Advanced Practice Registered Nurse (APRN) practice flexibility, including relaxing physician supervision mandates. These changes allow the PMHNP to practice to the full extent of their certification—independently counsel patients, prescribe medications, and consult —without physician oversight. 

2.   Further defined patient populations

In addition to the traditional patient groups, COVID-19 defined the patient population into focused groups to monitor pandemic effects and needs. In the beginning, the elderly population were quickly identified as an at-risk group. Then, the pandemic revealed the health disparities among underserved populations, shedding light on this chronic problem in health care.

Throughout the pandemic, additional patient populations were identified and assessed for risk of increased mental health needs or substance abuse. These groups included: health care workers, school-aged children and teens, university students, the homeless population, and the institutionalized. The expansion of these societal groups provides a detailed assessment of physical, emotional, and support needs.

3.   Lowered access barriers

Pre-pandemic barriers to psychiatric care included:

  • Limited access to care
  • Stigma associated with mental health care services
  • Cost of seeking treatment

Although telehealth was available, this service was limited due to insurance reimbursement and the cost of HIPAA-protected technology. During the pandemic, CMS expanded approval for telehealth services. Also, the Department of Health and Human Services (HHS) waived penalties for HIPAA violations associated with the use of technologies such as FaceTime, Skype, or WhatsApp.

Some mental health practices delivered care through drive-up clinics. These clinics continued pre-pandemic care to psychiatric patients by administering long-acting injectable medications, and safely participating in socially distant face-to-face appointments if telehealth was not an option. These drive-up clinics improved treatment and follow-up compliance throughout the pandemic.

Telehealth allowed better access to mental health services, and also allowed patients to be seen in their homes. This view into the patient’s home life provided valuable information about their surroundings, lifestyle, and support systems.

4.   Innovative practice opportunities

COVID-19 created a need for PMHNPs to consult with school administrations. Children and teens transitioning from the traditional school day to a virtual day struggle with isolation, depression, and anxiety. A school-aged child with a pre-existing diagnosis (such as ADHD or other behavioral and learning disabilities) may struggle with changes in routine and environment. PMHNPs can offer consulting services to the school and to parents to help children through these challenging times. PMHNPs are also needed for the post-pandemic period for readjustment back to daily in-person school.

Many patients initially reported depression and anxiety to primary care providers (PCP). The PMHNP is a valued consultant for the PCP to initiate holistic therapies, medications, and follow-up for these patients.

During the peak of the COVID-19 assault on New York City, a pair of Yale DNP graduates quickly identified that the city was in crisis. They responded by offering Lavender, an online psychiatry office employing 14 PMHNPs to provide counseling services. (Also an ANA 2021 Innovation Winner). Lavender offers same-day inquiry response, and transparent pricing that is approximately 30% less than existing psychiatric practices.

The pandemic revealed gaps in the current healthcare system and created a mental health emergency. However, PMHNPs are prepared to provide needed services through an expanded scope of practice, telehealth services for patient counseling, and consulting services to schools and medical practices.

Andrew Penn, RN, MS, NP, CNS, APRN-BC, an adult and psychiatric nurse practitioner, is exploring how COVID-19 has changed humanity. Society transitioned from overscheduled bustling lives in society, to adapting to the isolation of working from home, home-schooling children, and a nonexistent social life. These unexpected changes have left us exhausted and wary of the future. He cautions us to slowly emerge from our isolation, give attention to self-care, and look forward to a promising, and transformed future.

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