Tag: 8/11/21

Previously Infected Older People Have More COVID Antibodies

Photo by Adam Birkett on Unsplash

In a recent study published in Scientific Reports, researchers found that older people previously infected with COVID, when vaccinated, had higher antibody levels than previously infected individuals. These antibodies were also effective against the Delta variant, which wasn’t present in Canada when the samples were taken  in 2020.

Joelle Pelletier and Jean-François Masson, both professors in Université de Montréal’s Department of Chemistry, wanted to find out whether natural infection or vaccination led to more protective antibodies being generated. The focussed on an understudied group: people who have been infected but not hospitalised by SARS-CoV-2.

Consequently, 32 non-hospitalised COVID positive adults were recruited 14 to 21 days after being diagnosed through PCR testing. This was in 2020, before the Beta, Delta and Gamma variants emerged.

“Everyone who had been infected produced antibodies, but older people produced more than adults under 50 years of age,” said Prof Masson. “In addition, antibodies were still present in their bloodstream 16 weeks after their diagnosis.”

Antibodies produced after an infection by the original, “native” strain of the virus also reacted to SARS-CoV-2 variants that emerged in subsequent waves, namely Beta (South Africa), Delta (India) and Gamma (Brazil), but to a lesser extent: a reduction of 30 to 50%.

“But the result that surprised us the most was that antibodies produced by naturally infected individuals 50 and older provided a greater degree of protection than adults below 50, ” said Prof Pelletier.

“This was determined by measuring the antibodies’ capacity to inhibit the interaction of the Delta variant’s spike protein with the ACE-2 receptor in human cells, which is how we become infected,” he added. “We didn’t observe the same phenomenon with the other variants.”

When someone who has had a mild case of COVID is vaccinated, the antibody level in their blood doubles compared to an unvaccinated person who has been infected by the virus. Their antibodies are also better able to prevent spike-ACE-2 interaction.

“But what’s even more interesting,” said Prof Masson, “is that we have samples from an individual younger than 49 whose infection didn’t produce antibodies inhibiting spike-ACE-2 interaction, unlike vaccination. This suggests that vaccination increases protection against the Delta variant among people previously infected by the native strain.”

Both scientists believe more research should be conducted to determine the best combination for maintaining the most effective level of antibodies reactive to all variants of the virus.

Source: University of Montreal

Unemployed People Missed Out on Cancer Screenings

Source: National Cancer Institute

In a recent study, unemployed individuals in the US were less likely to have health insurance and be up to date on getting recommended cancer screening tests. Analyses published in the journal CANCER revealed that their lack of health insurance coverage completely accounted for their lower screening rates.

During the COVID pandemic, unemployment rates in the United States have risen to levels not seen since the Great Depression. To examine associations between unemployment, health insurance, and cancer screening, Stacey Fedewa, PhD, of the American Cancer Society, and her colleagues analysed information from adults under age 65 years who responded to a nationally representative annual survey of the general population.

Unemployed adults were four times more likely to lack insurance than employed adults (41.4% vs 10.0%). A lower proportion of unemployed adults had received up-to-date cervical (78.5% vs 86.2%), breast (67.8% vs 77.5%), colorectal (41.9% vs 48.5%), and prostate (25.4% vs 36.4%) cancer screening. These differences were eliminated after accounting for health insurance coverage.

“People who were unemployed at the time of the survey were less likely to have a recent cancer screening test and they were also less likely to be up-to-date with their cancer screenings over the long term. This suggests that being unemployed at a single point in time may hinder both recent and potentially longer-term screening practices,” said Dr. Fedewa. This can increase a person’s risk of being diagnosed with late-stage cancer, which is more difficult to treat than cancer that is detected at an early stage.

“Our finding that insurance coverage fully accounted for unemployed adults’ lower cancer screening utilisation is potentially good news, because it’s modifiable,” Dr Fedewa added. “When people are unemployed and have health insurance, they have screening rates that are similar to employed adults.”

The findings highlight insurance coverage’s importance in access to recommended cancer screening tests and indicate that insurance needs to be extended to all people, regardless of their employment status.

Source: Wiley

Scientist Identify the Gene Responsible for Doubling Severe COVID Risk

Image source: Pixabay

Scientists at Oxford University have identified the gene responsible for doubling the risk of respiratory failure from COVID. Some 60% of people of South Asian descent carry the high-risk genetic signal, partly explaining the impact of COVID in the Indian subcontinent and the excess deaths seen in some UK communities.

Prior research already identified a stretch of DNA on chromosome 3 which doubled the COVID mortality risk of adults under 65. However, scientists did not know how this genetic signal worked to increase the risk, nor the exact genetic change that was responsible.

In a study published in Nature Genetics, an Oxford University team used cutting edge technology to work out which gene was causing the effect, and how it was doing so.

Study co-lead Jim Hughes, Professor of Gene Regulation, said: “The reason this has proved so difficult to work out, is that the previously identified genetic signal affects the ‘dark matter’ of the genome. We found that the increased risk is not because of a difference in gene coding for a protein, but because of a difference in the DNA that makes a switch to turn a gene on. It’s much harder to detect the gene which is affected by this kind of indirect switch effect.”

The team trained an artificial intelligence algorithm to analyse huge quantities of genetic data from hundreds of types of cells from all parts of the body, to show that the genetic signal is likely to affect cells in the lung. Then the researchers used a newly developed precision technique to zero in on the DNA at the genetic signal. This examines the way that the billions of DNA letters fold up to fit inside a cell to locate the specific gene that was being controlled by the sequence that increases severe COVID risk.

Dr Damien Downes, who led laboratory work, said: “Surprisingly, as several other genes were suspected, the data showed that a relatively unstudied gene called LZTFL1 causes the effect.”

The researchers found that the higher risk version of the gene probably prevents the cells lining airways and the lungs from responding to the virus properly. But importantly it doesn’t affect the immune system, so the researchers expect people carrying this version of the gene to respond normally to vaccines.

The researchers are also hopeful that drugs and other therapies could target the pathway preventing the lung lining from transforming to less specialised cells, raising the possibility of new treatments customised for those most likely to develop severe symptoms.

Study co-lead Professor James Davies, Associate Professor of Genomics at Oxford University, said: “The genetic factor we have found explains why some people get very seriously ill after coronavirus infection. It shows that the way in which the lung responds to the infection is critical. This is important because most treatments have focussed on changing the way in which the immune system reacts to the virus.”

About 60% of people with South Asian ancestry carried this higher-risk version of the gene compared to 15% of those with European ancestry – explaining in part the higher death rates and hospitalisations in the former group. The study also found that 2% of people with Afro-Caribbean ancestry carried the higher risk genotype, meaning that this genetic factor does not completely explain the higher death rates reported for black and minority ethnic communities.

Prof Davies explained: “The higher risk DNA code is found more commonly in some black and minority ethnic communities but not in others. Socioeconomic factors are also likely to be important in explaining why some communities have been particularly badly affected by the COVID pandemic.

“Although we cannot change our genetics, our results show that the people with the higher risk gene are likely to particularly benefit from vaccination. Since the genetic signal affects the lung rather than the immune system, it means that the increased risk should be cancelled out by the vaccine.”

Source: Oxford University

Better Outcomes with Earlier Adrenaline Treatment in Cardiac Arrest

Source: Mat Napo on Unsplash

Earlier adrenaline treatment during a cardiac arrest is linked to better recovery compared to later treatment, according to preliminary research to be presented at the American Heart Association’s Resuscitation Science Symposium (ReSS) 2021.

“Our study’s findings should guide emergency medical services professionals towards earlier administration of epinephrine [adrenaline] during out-of-hospital cardiac arrest management,” said lead study author Shengyuan Luo, MD, MHS, an internal medicine resident physician at Rush University Medical Center in Chicago.

Previous research found that only about 1 in 5 people survive a cardiac arrest outside of the hospital and those who do survive often have long-term impairment in the ability to perform daily living tasks.

During a cardiac arrest, immediate CPR (cardiopulmonary resuscitation) is critical. For some types of cardiac arrest, an AED (automated external defibrillator) also is used to deliver an electric shock through the chest to the heart to restore a heartbeat. For these ‘shockable’ cardiac arrests, adrenalineis injected to help restore blood flow. Previous research indicated that adrenaline should be given after three unsuccessful electric shocks with an AED, however, it was unclear whether it should be given even earlier – such as after the first electric shock.

To compare the effects of earlier versus later administration of adrenaline, the researchers examined medical records to compare epinephrine timing to patient recovery. Study subjects included 6416 multi-ethnic adults across North America who had an out of hospital cardiac arrest with shockable initial rhythm from 2011-2015. They were an average age of 64 years, and most were men.

Overall, adrenaline administration within four minutes after the first shock from an AED was associated with greater chances of recovery, while administration after four minutes was associated with reduced chances. Specifically, people who received adrenaline after four minutes were nearly half as likely to have heartbeat and blood flow restored before hospital admittance and half as likely to survive to hospital discharge or be able to perform daily tasks, as measured by a standard test, at discharge. Additionally, the risks of later adrenaline treatment rose with each minute of delayed treatment.

“It is crucial that whenever a cardiac arrest event is suspected, the emergency medical system be notified and activated immediately, so that people with cardiac arrest receive timely, life-saving medical care,” Dr Luo said.

These findings support the latest American Heart Association CPR and Emergency Cardiovascular Care Guidelines, which were released in October 2020. The guidelines indicate adrenaline should be administered as early as possible to maximise good resuscitation outcome chances. The guideline recommendation was based on previous observational data that suggest better outcomes when adrenaline is given sooner.

Source: EurekAlert!

Firefighters’ Blood Pressure Soars in an Emergency

Source: Pixabay CC0

When the emergency alarm sounds, blood pressure (BP) among firefighters often soars, according to preliminary research presented at the American Heart Association’s Scientific Sessions 2021.

“All emergency and first responders should be aware of their health. They should know what their typical blood pressure level is and be aware of how it fluctuates. Most important, if they have high blood pressure, they should make sure it is well-controlled,” said senio author Deborah Feairheller, PhD.

The study recruited 37 male and 4 female volunteer and municipal firefighters who wore ambulatory BP monitors during an on-call work shift lasting at least 12 consecutive hours. In addition to the automatic BP readings from the monitor, study participants were instructed to prompt the monitor to take a BP reading whenever a pager or emergency call sounded and whenever they felt they entered a stressful situation. Participants also logged activities and call types for each measurement. The firefighters’ average age was 41.2 years. Average body mass index (BMI) of all participants was 30.3, with BMI ≥ 25 defined as overweight, while BMI ≥ 30 is defined as obesity. The firefighters all had high blood pressure, defined as systolic BP as 130 mm Hg or higher, or a diastolic BP of 80 mm Hg or higher, as defined by the American Heart Association’s most recent guideline.

The findings were that:

  • Average BP and heart rate (HR) were 131/79.3 mmHg and 75.7 beats per minute (bpm) respectively.
  • Compared with the reading immediately preceding the call, systolic BPsurged an average of 19.2 mm Hg with fire calls and 18.7 mm Hg with medical calls.
  • Meanwhile, diastolic BP surged 10.5 mm Hg with fire calls and 16.5 mm Hg with medical calls.
  • Compared with the average BP during the entire 12-hour shift, systolic BP was 9% higher during fire calls, and diastolic BP was 9% higher during medical calls.
  • Average HR also increased during both types of calls: 10bpm with fire calls, and 15bpm for medical calls.
  • There were no significant differences in BP, HR or BP surge levels when comparing responses among fire calls, medical calls, riding an emergency vehicle or false alarms.

Surprising findings
“The public knows the value that emergency responders provide to communities. We hope to increase awareness that many firefighters have hypertension and that their blood pressure can increase to very dangerous levels when responding to emergency calls,” said Dr Feairheller.

“The current data show that almost 75% of firefighters have hypertension, and less than 25% have their blood pressure under control. I hope that our research can help identify occupational factors that affect blood pressure and increase awareness among this population,” Dr Feairheller added.

They were also surprised at the findings on diastolic BP increases. “We anticipated systolic blood pressure surges because that reading is usually more responsive to stimuli; however, the extent of the diastolic blood pressure surge was unexpected,” said Dr Feairheller.

The investigators are currently exploring whether diet and exercise regimens could help to lower the BP surge that firefighters experience during emergency calls.

Source: EurekAlert!