Pandemic News Links / Current News Updates

curncman
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Moderna Just Made the Pfizer Vaccine's Biggest Weakness an Even Bigger One

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Moderna Just Made the Pfizer Vaccine's Biggest Weakness an Even Bigger One

https://www.msn.com/en-us/money/topstoc ... d=msedgntp
Pfizer (NYSE: PFE) and Moderna (NASDAQ: MRNA) have been close rivals in the COVID-19 vaccine race ever since they announced the starts of their phase 3 vaccine trials -- on the very same day back in July. But Pfizer edged ahead en route to the finish line. The big pharmaceutical company scored the first FDA emergency use authorization (EUA) for a coronavirus vaccine in December.



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curncman
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Re: Ralph Steinman, Nobel prize winner, speaks about dendritic cells and immune-based vacciNews Links / Current News Upd

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Ralph Steinman, Nobel prize winner, speaks about dendritic cells and immune-based vaccines

This was 9 years ago
He was so ahead of his time! He even used his own research on his own cancer. Although technology at the time of his death was very early in what we call immunotherapy, he was battling his cancer with just vaccines

curncman
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Novavax Secures Additional $147M From Warp Speed Program For COVID-19 Vaccine

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Novavax Secures Additional $147M From Warp Speed Program For COVID-19 Vaccine

https://finance.yahoo.com/news/novavax- ... 43481.html

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-19.26%
Vandana Singh
Fri, April 30, 2021, 11:53 AM

NVAX
-19.26%

According to an SEC filing, Novavax Inc (NASDAQ: NVAX) has received an additional $147.3M as part of Operation Warp Speed to develop a COVID-19 vaccine dubbed NVX-CoV2373.

This addition brings its total from the program to $1.74 billion, which was announced in July last year.

President Joe Biden directly mentioned the company earlier this week, saying that upcoming vaccines, including one from Novavax, could be shared with other countries.

Early data out this year showed its vaccine could keep up in efficacy terms with the vaccine leaders, namely Pfizer Inc (NYSE: PFE) - BioNTech SE (NASDAQ: BNTX), and Moderna Inc (NASDAQ: MRNA).

While behind in authorizations compared to its rivals, which also now include AstraZeneca Plc (NASDAQ: AZN) and Johnson & Johnson (NYSE: JNJ) (though both have been hit recently with some safety concerns), with the rise of variants and outbreaks in highly populated places like Brazil and India, it still has a place globally to deliver billions of doses.
curncman
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Antibody drug neutralizes virus variants in lab study; COVID-19 antibodies detectable 12 months after infection

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Antibody drug neutralizes virus variants in lab study; COVID-19 antibodies detectable 12 months after infection

https://www.yahoo.com/news/antibody-dru ... 59377.html

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Nancy Lapid
Mon, May 3, 2021, 2:42 PM
By Nancy Lapid

(Reuters) - The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.

Experimental antibody drug neutralizes COVID-19 variants

An experimental monoclonal antibody treatment for COVID-19 being developed by Eli Lilly and Co and AbCellera Biologics Inc can "potently" neutralize numerous coronavirus variants, including those first identified in the UK, Brazil, South Africa, California and New York, scientists have found in test tube experiments. The antibody - known as LY-CoV1404 or LY3853113 - works by attaching itself to a place on the virus that has shown few signs of mutating, which means the drug is likely to retain its effectiveness over time, the researchers said in a report posted on Friday on bioRxiv ahead of peer review. "New variant-resistant treatments such as LY-CoV1404 are desperately needed, given that some of the existing therapeutic antibodies are less effective or ineffective against certain variants and the impact of variants on vaccine efficacy is still poorly understood," the research team wrote. An AbCellera spokesperson said the company plans to release information about tests of the drug in humans on Tuesday. (https://bit.ly/3gYQnAU)

COVID-19 antibodies still detectable at 12 months

Some COVID-19 survivors infected early in the pandemic still have detectable antibodies against the virus a year later, according to a new study. U.S. doctors collected blood samples from 250 patients, including 58 who had been hospitalized for COVID-19 and 192 who had not required hospitalization. Six-to-10 months after diagnosis, all of the former inpatients and 95% of the outpatients still had neutralizing antibodies, according to a report posted on Sunday on medRxiv ahead of peer review. In the small subset of those followed for a full year, 8-of-8 people who had been hospitalized still had antibodies, as did 9-of-11 former outpatients. Antibody levels at the time of follow-up were correlated with age and with COVID-19 severity. Older age was linked with higher neutralizing antibody levels, whereas levels were "lower and more variable" in participants under age 65 who experienced less severe COVID-19 and did not require hospitalization, the researchers reported. They said vaccination of COVID-19 survivors "would be prudent" because vaccine-induced protection against the virus will likely be more long-lived than antibodies induced by mild COVID-19. (https://bit.ly/3eelS82)

No link seen between COVID-19 and aspirin or ibuprofen

A large new study found no indication that use of non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin or ibuprofen increases people's vulnerability to infection by the new coronavirus. Because early reports had suggested such a link, researchers used the COVID Symptom Study smartphone app to query more than 2.7 million individuals in the United States, the UK and Sweden about their use of aspirin and other NSAIDs, as well as about virus symptoms, COVID-19 testing, and healthcare seeking behavior. Close to 9,000 participants reported a positive COVID-19 test during the study, according to a report posted on Sunday on medRxiv in advance of peer review. After accounting for individuals' lifestyle factors, other illnesses, and symptoms, regular use of NSAIDs was not associated with a higher risk of becoming infected with the coronavirus. "There have been lingering concerns" that commonly used NSAIDs "could increase the risk of COVID infection or worsen the disease course among those who acquire the infection," said coauthor Dr. Andrew Chan of the Massachusetts General Hospital in Boston. "Our study shows that there is no such an association and initial concerns were probably due to the fact that individuals with other risk factors for COVID or symptoms of COVID were more likely to take NSAIDs, rather than a cause and effect relationship," he said.
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Re: Pandemic News Links / Current News Updates

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33% of neighborhoods in largest US cities were 'pharmacy deserts'

5/3/21

https://medicalxpress.com/news/2021-05- ... rmacy.html


Black and Latino neighborhoods in the 30 most populous U.S. cities had fewer pharmacies than white or diverse neighborhoods in 2007-2015, USC research shows, suggesting that 'pharmacy deserts'- like so-called food deserts-may be an overlooked contributor to persistent racial and ethnic health disparities.

Pharmacies are increasingly vital points of care for essential health services. In addition to filling prescriptions to treat chronic health conditions, pharmacists dispense emergency doses of naloxone to reverse opioid overdoses, contraceptives to prevent unplanned pregnancy and COVID-19 testing and vaccinations.

But many neighborhoods in major cities such as Los Angeles, Chicago, Houston, and Memphis lack convenient access to a pharmacy, according to research published published today in the May issue of the journal Health Affairs.

"We focused on cities because of racial/ethnic residential segregation and the fact that more than 80% of the Black and Latino population in the U.S. live in cities," said senior author Dima Mazen Qato, Hygeia Centennial Chair and associate professor of pharmacy at the USC School of Pharmacy and senior fellow at the USC Schaeffer Center for Health Policy & Economics.

"Our findings suggest that addressing disparities in geographic access to pharmacies—including pharmacy closures—is imperative to improving access to essential medications and other health care services in segregated minority neighborhoods," said Qato, who directs the Program on Medicines and Public Health.

"One in three neighborhoods throughout these cities were pharmacy deserts, affecting nearly 15 million people," said Jenny S. Guadamuz, study first author and Postdoctoral Fellow at the USC Schaeffer Center and the USC Program on Medicines and Public Health at the USC School of Pharmacy. "However, limited access to pharmacies disproportionately impacts racial/ethnic minorities—8.3 million Black and Latino residents of these cities live in deserts."

Researchers focused on census tracts/neighborhoods in cities with populations of 500,000 or more. Census tracts, smaller than ZIP code areas, generally have a population size between 1,200 and 8,000 people. Data from the U.S. Census Bureau's American Community Survey established neighborhood characteristics including total population, and percentage of the population by race/ethnicity, low-income status and vehicle ownership. Pharmacy locations and types of pharmacies came from National Council for Prescription Drug Programs.

Researchers overlaid census tract maps with pharmacy locations. Neighborhoods where the average distance to the nearest pharmacy was 1.0 mile or more were classified as pharmacy deserts. In neighborhoods that were low income and had at least 100 households with no vehicle, the qualifying distance dropped to 1/2 mile or more, to account for transportation barriers.

"Traveling a mile to get your prescription medications may be convenient for people that own a car. Traveling a mile, or even ½ a mile, may be difficult for people who live in low-income neighborhoods and don't drive, particularly older adults who rely on walking or public transportation," said Qato.

Prevalence of pharmacy deserts varied widely across cities. In New York and Philadelphia, for example, fewer than 10 percent of neighborhoods met the definition of pharmacy deserts. On the other hand, more than 60 percent of neighborhoods in Indianapolis, San Antonio, and Charlotte were pharmacy deserts.

In all cities, segregated Black or Latino neighborhoods, or both, were more likely to be pharmacy deserts than white or diverse neighborhoods. These disparities were most pronounced in Los Angeles, Chicago, Albuquerque, Dallas, Memphis, Boston, Milwaukee, Baltimore and Philadelphia.

"We observed stark disparities in Los Angeles, where one-third of all Black and Latino neighborhoods were pharmacy deserts, particularly neighborhoods in South Central LA, including Florence, Broadway-Manchester and Watts," said Guadamuz.

Among all the cities examined, the most pronounced disparities were in Chicago, where 1% of white neighborhoods were pharmacy deserts in comparison to 33% of Black neighborhoods in the South Side neighborhoods of Chatham, West Pullman and Greater Grand Crossing, Guadamuz added.

The researchers said policies could help address the situation. For example, federal, state, and local governments could deploy targeted grants and tax benefits to encourage pharmacies to locate in pharmacy deserts. Other incentives could motivate pharmacies to offer services such as home delivery to improve access.

"Increasing Medicaid and Medicare pharmacy reimbursement rates for prescription medications might encourage pharmacies to open in areas of need," Guadamuz said. "To ensure existing pharmacies don't close, policymakers need to make sure that stores serving Black and Latino areas are not excluded from pharmacy networks."
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Re: Pandemic News Links / Current News Updates

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UTEP researchers use real-time 3D animation to study motor impairments in children with autism

4/30/21


https://www.news-medical.net/news/20210 ... utism.aspx

For more than a year, researchers at The University of Texas at El Paso's Stanley E. Fulton Gait Research & Movement Analysis Lab in the College of Health Sciences have been using real-time 3D animation to investigate motor impairments in children who have autism spectrum disorder (ASD). Their aim is to understand how children with autism can learn motor skills, so that they can receive effective therapies.

The results of their study, titled "Children With Autism Exhibit More Individualized Responses to Live Animation Biofeedback Than Do Typically Developing Children," were recently published in the journal of Perceptual and Motor Skills. The paper's release coincides with National Autism Awareness Month in April.

" The greatest takeaway from this study is that when teaching or coaching new movements to an individual with autism, the teacher or coach needs to understand the individual with autism's specific motor learning characteristics. They need to look specifically at each child's needs because each child is different."

- Jeffrey Eggleston, Ph.D., study's lead author, assistant professor of kinesiology and Gait lab director

The study's other authors include Alyssa N. Olivas, a student in the doctoral biomedical engineering program; Heather R. Vanderhoof and Emily A. Chavez, students in the Interdisciplinary Health Sciences (IHS) doctoral program; Carla Alvarado, M.D., board certified psychiatrist; and Jason B. Boyle, Ph.D., associate professor and interim chair of Kinesiology at UTEP.

More than 80% of children with ASD have gross motor skills issues, such as problems with balance and coordination, which can interfere with their communication and social interactions.

The 18-month UTEP study incorporated live animation biofeedback to teach 15 children who have ASD and were between the ages of 8 and 17 how to do a squat, a strength exercise that works multiple muscle groups in the body's lower extremities.

Researchers compared their movement patterns to children without the disorder. They found that children with ASD displayed highly individualized responses to the live animation biofeedback, much more so than children with typical development, Eggleston said.

In the lab, children had 1-inch cubes called inertial measurement unit (IMU) sensors strapped to their pelvis, thighs, lower legs and feet. They followed an animation model on a computer screen, which showed them how to squat. The children would then try to perform the squat without looking at the animation.

IMU sensors captured the movement of the child's lower extremities. The data was relayed to a computer graphics program via Bluetooth, which was transposed into a skeletal animation of the child squatting and then standing back up on the computer screen.

The study, which took place before the COVID-19 pandemic, was funded through a nearly $15,000 grant from the J. Edward and Helen M. C. Stern Foundation and UTEP's kinesiology department.

Source:


University of Texas at El Paso

Journal reference:


Eggleston, J.D., et al. (2021) Children With Autism Exhibit More Individualized Responses to Live Animation Biofeedback Than Do Typically Developing Children. Perceptual and Motor Skills. doi.org/10.1177/0031512521998280.
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Re: Pandemic News Links / Current News Updates

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Scientists develop an ultrasonic imaging system to visualize cell abnormalities in 3D

4/30/21


https://www.news-medical.net/news/20210 ... in-3D.aspx


Scientists at the University of Nottingham have developed an ultrasonic imaging system, which can be deployed on the tip of a hair-thin optical fiber, and will be insertable into the human body to visualize cell abnormalities in 3D.

The new technology produces microscopic and nanoscopic resolution images that will one day help clinicians to examine cells inhabiting hard-to-reach parts of the body, such as the gastrointestinal tract, and offer more effective diagnoses for diseases ranging from gastric cancer to bacterial meningitis.

The high level of performance the technology delivers is currently only possible in state-of-the-art research labs with large, scientific instruments - whereas this compact system has the potential to bring it into clinical settings to improve patient care.

The Engineering and Physical Sciences Research Council (EPSRC)-funded innovation also reduces the need for conventional fluorescent labels - chemicals used to examine cell biology under a microscope - which can be harmful to human cells in large doses.

The findings are being reported in a new paper, entitled 'Phonon imaging in 3D with a fibre probe' published in the Nature journal, Light: Science & Applications.

Paper author, Salvatore La Cavera, an EPSRC Doctoral Prize Fellow from the University of Nottingham Optics and Photonics Research Group, said of the ultrasonic imaging system: "We believe its ability to measure the stiffness of a specimen, its bio-compatibility, and its endoscopic-potential, all while accessing the nanoscale, are what set it apart. These features set the technology up for future measurements inside the body; towards the ultimate goal of minimally invasive point-of-care diagnostics."

Currently at prototype stage, the non-invasive imaging tool, described by the researchers as a "phonon probe", is capable of being inserted into a standard optical endoscope, which is a thin tube with a powerful light and camera at the end that is navigated into the body to find, analyse, and operate on cancerous lesions, among many other diseases. Combining optical and phonon technologies could be advantageous; speeding up the clinical workflow process and reducing the number of invasive test procedures for patients.

3D mapping capabilities

Just as a physician might conduct a physical examination to feel for abnormal 'stiffness' in tissue under the skin that could indicate tumors, the phonon probe will take this '3D mapping' concept to a cellular level.

By scanning the ultrasonic probe in space, it can reproduce a three-dimensional map of stiffness and spatial features of microscopic structures at, and below, the surface of a specimen (e.g. tissue); it does this with the power to image small objects like a large-scale microscope, and the contrast to differentiate objects like an ultrasonic probe.

"Techniques capable of measuring if a tumor cell is stiff have been realised with laboratory microscopes, but these powerful tools are cumbersome, immobile, and unadaptable to patient-facing clinical settings. Nanoscale ultrasonic technology in an endoscopic capacity is poised to make that leap."

- Salvatore La Cavera, an EPSRC Doctoral Prize Fellow, University of Nottingham Optics and Photonics Research Group

How It Works

The new ultrasonic imaging system uses two lasers that emit short pulses of energy to stimulate and detect vibrations in a specimen. One of the laser pulses is absorbed by a layer of metal - a nano-transducer (which works by converting energy from one form to another) - fabricated on the tip of the fibre; a process which results in high-frequency phonons (sound particles) getting pumped into the specimen. Then a second laser pulse collides with the sound waves, a process known as Brillouin scattering. By detecting these "collided" laser pulses, the shape of the travelling sound wave can be recreated and displayed visually.

The detected sound wave encodes information about the stiffness of a material, and even its geometry. The Nottingham team was the first to demonstrate this dual-capability using pulsed lasers and optical fibres.

The power of an imaging device is typically measured by the smallest object that can be seen by the system, i.e. the resolution. In two dimensions the phonon probe can "resolve" objects on the order of 1 micrometre, similar to a microscope; but in the third dimension (height) it provides measurements on the scale of nanometres, which is unprecedented for a fibre-optic imaging system.
Future applications

In the paper, the researchers demonstrate that the technology is compatible with both a single optical fibre and the 10-20,000 fibres of an imaging bundle (1mm in diameter), as used in conventional endoscopes.

Consequently, superior spatial resolution and wide fields of view could routinely be achieved by collecting stiffness and spatial information from multiple different points on a sample, without needing to move the device - bringing a new class of phonon endoscopes within reach.

Beyond clinical healthcare, fields such as precision manufacturing and metrology could use this high-resolution tool for surface inspections and material characterisation; a complementary or replacement measurement for existing scientific instruments. Burgeoning technologies such as 3D bio-printing and tissue engineering could also use the phonon probe as an inline inspection tool by integrating it directly to the outer diameter of the print-needle.

Next, the team will be developing a series of biological cell and tissue imaging applications in collaboration with the Nottingham Digestive Diseases Centre and the Institute of Biophysics, Imaging and Optical Science at the University of Nottingham; with the aim to create a viable clinical tool in the coming years.

Source:

University of Nottingham

Journal reference:


La Cavera, S., et al. (2021) Phonon imaging in 3D with a fibre probe. Light: Science & Applications. doi.org/10.1038/s41377-021-00532-7.
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Re: Pandemic News Links / Current News Updates

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The vulnerable homebound are left behind on vaccination

4/30/21


https://www.news-medical.net/news/20210 ... ation.aspx


It was April, more than three months into the vaccination campaign against covid-19, and Jim Freeman, 83, still had not gotten his first dose.

Freeman had been eligible for months as part of the 75-and-older target group deemed most vulnerable to death and serious illness in the pandemic. But he could not leave his home to make the journey to one of the mass-vaccination sites in San Mateo County. Freeman, who has Parkinson's disease, has extremely limited mobility and no longer can walk.

"He watches TV at night and sees all these people in line getting vaccines, but he couldn't do it," said his daughter Beth Freeman, 58. "It was really frustrating." She contacted the county and state public health departments and even her local congresswoman for help, but none had a solution.

Finally, after weeks of failed attempts to get someone to vaccinate her father at their home, Beth spent $700 to rent a special wheelchair-accessible van and, with the help of a home health aide, nervously drove her father to the county's mass-vaccination site.

Even as the nation has moved on to vaccinating everyone 16 and older, the vast majority of homebound people have not yet been vaccinated, said Kelly Buckland, executive director of the National Council on Independent Living. "As far as I can tell, no one's really doing it. Maybe a few places in the country, but not on the mass scale it needs to be."

Across the nation, an estimated 4 million Americans are homebound by age, disability or frailty, unable to easily leave their homes to receive a covid vaccine.

Buckland noted that, while homebound people are not out in public where the virus is circulating, they don't live in a bubble. Most rely for care on family members or a rotating staff of home health aides who come and go and often have their own homes and families. "For people with disabilities, you can't close yourself off. You don't have the option. People have to come into your home every day to give you services."

The Biden administration in late March dedicated $100 million to help vulnerable older adults and people with disabilities get vaccinations. But many caregivers and homebound people say they aren't yet feeling the impact of that effort.

California, where tens of thousands of residents like Jim Freeman are still waiting their turn for vaccination, offers a sharp lens on the challenges.

Marta Green, a California official helping oversee vaccine distribution, said during an April meeting of the state's Community Vaccine Advisory Committee that California is "working on a partnership" to send ambulances to vaccinate homebound people where they live. In response to questions about how many homebound people had been vaccinated so far, a spokesperson for the California Department of Public Health said the effort was "just beginning" and estimates were not available.

As part of a $15 million no-bid contract with California to administer the state's vaccination program, Blue Shield of California is obligated to provide vaccine access to homebound people. The company, nonetheless, declined to provide responses to specific questions about such efforts. Spokesperson Erika Conner said the company has "diligently explored opportunities for this work" and recommended that homebound people contact their local public health departments or health care providers.

The logistics of inoculating homebound people with a vaccine that requires cold storage is not simple. Once thawed, a vial of Pfizer-BioNTech vaccine contains six doses that must be delivered within six hours, while a Moderna vaccine vial contains 10 to 15 doses to be used within 12 hours. With each vaccination visit lasting about an hour plus the travel time, there isn't much room for error, especially in rural areas where residents may live far apart. The one-dose Johnson & Johnson vaccine offers more flexibility, but the pause due to safety concerns resulted in delays.

"Yeah, it's not easy. If it were easy, we'd already have done it," said Dr. Mike Wasserman, a geriatrician and member of the California vaccine advisory committee. "But that's not an excuse. These are the folks who if they get the virus they're going to die. I don't accept it."

Wasserman said he'd give the state a "D" for its efforts to reach the homebound for vaccination. For some, he added, it might already be too late. "If you're 80 years old and you live in a 1,000-square-foot home with 10 other people, you're probably dead already."

In the absence of a coordinated state-driven effort, California counties are attempting a patchwork of approaches.

In Los Angeles County, the public health department has partnered with the sheriff’s department and 15 fire departments to vaccinate homebound residents, with some success. Health officials projected that 50% of the county's 10,000 homebound residents will have received one dose by the end of April.

In Fresno County, with more than a million residents, health officials said they are compiling a list of homebound people who want help getting a vaccine. So far, fewer than 20 people in that category have been contacted and received the vaccine.

In San Mateo County, where Freeman lives, the health department has identified at least 1,000 individuals who are homebound and in need of the vaccine; so far, 100 have been vaccinated.

Before she resorted to renting the $700 mobility van for her father, Beth Freeman contacted county workers. They offered to send a bus to pick up her father and take him to a vaccination site, but she couldn't imagine how that would work for him, both in terms of the physical logistics and the risk of exposure. She asked the nurses who visited her father twice a week through Sutter Health's care-at-home program for help — after all, they had given him the flu shot. But no luck. The nurses said they were not allowed to offer the covid vaccine.

Finally, on April 6, Beth made the difficult decision to transport her father despite his limited mobility. "I did not want to take him out of the house for this. It was risky for his health. But at some point I realized it wasn't going to happen any other way," she said. "He wanted to see members of his family and time was ticking."

She said her father was up all night worrying, and his body was stiff. But with help from a home health aide, she used a special lift to hoist him into a wheelchair and wheeled him down two ramps and into the rented van, where she strapped him to the chair. They drove 20 minutes to the San Mateo County Event Center, her eyes darting from the road to the rearview mirror to check on her father, and then waited 40 minutes in the drive-thru line.

"When I rolled down the window, the nurses were like, What the hell? Why is he only coming to us now?" she said. The experience was so stressful for her father, she added, that he slept on and off for the next two days.

This week, they repeated the ordeal for his second dose — including laying out another $700 for the rental van. "All this, while he sees nurses at home twice a week?" Beth Freeman said. "What a missed opportunity."
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Paul Offit, MD: Latest on COVID-19 vaccines and their safety, herd immunity, & viral variants

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Paul Offit, MD: Latest on COVID-19 vaccines and their safety, herd immunity, & viral variants

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Re: Pandemic News Links / Current News Updates

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'Last resort' antibiotic pops bacteria like balloons

5/4/21


https://phys.org/news/2021-05-resort-an ... loons.html


Scientists have revealed how an antibiotic of 'last resort' kills bacteria.

The findings, from Imperial College London and the University of Texas, may also reveal a potential way to make the antibiotic more powerful.

The antibiotic colistin has become a last resort treatment for infections caused by some of the world's nastiest superbugs. However, despite being discovered over 70 years ago, the process by which this antibiotic kills bacteria has, until now, been something of a mystery.

Now, researchers have revealed that colistin punches holes in bacteria, causing them to pop like balloons. The work, funded by the Medical Research Council and Wellcome Trust, and published in the journal eLife, also identified a way of making the antibiotic more effective at killing bacteria.

Colistin was first described in 1947, and is one of the very few antibiotics that is active against many of the most deadly superbugs, including E. coli, which causes potentially lethal infections of the bloodstream, and Pseudomonas aeruginosa and Acinetobacter baumannii, which frequently infect the lungs of people receiving mechanical ventilation in intensive care units.

These superbugs have two 'skins', called membranes. Colistin punctures both membranes, killing the bacteria. However, whilst it was known that colistin damaged the outer membrane by targeting a chemical called lipopolysaccharide (LPS), it was unclear how the inner membrane was pierced.

Now, a team led by Dr. Andrew Edwards from Imperial's Department of Infectious Disease, has shown that colistin also targets LPS in the inner membrane, even though there's very little of it present.

Dr. Edwards said: "It sounds obvious that colistin would damage both membranes in the same way, but it was always assumed colistin damaged the two membranes in different ways. There's so little LPS in the inner membrane that it just didn't seem possible, and we were very sceptical at first. However, by changing the amount of LPS in the inner membrane in the laboratory, and also by chemically modifying it, we were able to show that colistin really does puncture both bacterial skins in the same way—and that this kills the superbug. "

Next, the team decided to see if they could use this new information to find ways of making colistin more effective at killing bacteria.

They focussed on a bacterium called Pseudomonas aeruginosa, which also causes serious lung infections in people with cystic fibrosis. They found that a new experimental antibiotic, called murepavadin, caused a build up of LPS in the bacterium's inner skin, making it much easier for colistin to puncture it and kill the bacteria.

The team say that as murepavadin is an experimental antibiotic, it can't be used routinely in patients yet, but clinical trials are due to begin shortly. If these trials are successful, it may be possible to combine murepavadin with colistin to make a potent treatment for a vast range of bacterial infections.

Akshay Sabnis, lead author of the work also from the Department of Infectious Disease, said: "As the global crisis of antibiotic resistance continues to accelerate, colistin is becoming more and more important as the very last option to save the lives of patients infected with superbugs. By revealing how this old antibiotic works, we could come up with new ways to make it kill bacteria even more effectively, boosting our arsenal of weapons against the world's superbugs."
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