Tag: expert opinion

Categories : COVIDTags :

Living with COVID: SA’s New Approach

On By ModernMedia
Image by Quicknews

South Africa’s easing of COVID regulations at the end of 2021 set a new trend in how countries are choosing to manage the pandemic. In an article for The Conversation, Wits University’s Professor Shabir Madhi and colleagues reflect on the boldness – and the risks.

In a significant departure, the government is choosing a new, more pragmatic approach while keeping an eye on severe COVID and threats to health systems. This reflects a willingness to “live with the virus” without causing further damage to the economy and livelihoods, especially in a resource-constrained country.

Prof Madhi and colleagues hope that “the government continues to pursue this approach and doesn’t blindly follow policies that are not feasible in the local context, and ultimately yield nominal benefit.”

This more nuanced approach is a stark contrast to reflexive restrictions in response to rising case rates, suggesting the government has listened to commentary saying that the focus should be on whether health systems are under threat.

A high level of population immunity guides this approach. A sero-survey in Gauteng, just prior to the onset of the Omicron wave indicated that 72% of people had been infected over the course of the first three waves. Sero-positivity was 79% and 93% in COVID unvaccinated and vaccinated people aged over 50: a group that had previously made up a high percentage of hospitalisations and deaths.

The sero-survey data show that immunity against severe COVID in the country has largely evolved through natural infection over the course of the first three waves and prior to the advent of vaccination. This has, however, come at the massive cost of 268 813 deaths based on excess mortality attributable to COVID

Antibody presence is a proxy for underlying T-cell immunity which appears to play an important role in reducing the risk of infection progressing to severe COVID. Current evidence indicates that such T cell immunity, which has multiple targets and even more so when induced by natural infection, is relatively unaffected even by Omicron’s many mutations and likely lasts more than a year. This sort of underpinning T-cell immunity protecting against severe disease should provide breathing space for at least the next 6–12 months, and possibly further.

Despite Omicron’s anti-spike evasion, vaccine and natural infection induced T-cell immunity has been relatively preserved. This could explain the uncoupling of case rate to hospitalisation and death rates. Omicron’s mutations also appear to make it predisposed to infecting the upper rather than the lower airway, reducing the likelihood of progressing to severe disease.

In the meantime, they stress that greater vaccine uptake is ensured, along with boosters for high-risk groups.

Additionally, since low test rates mean only 10% of infections are actually documented in SA , isolation and quarantine are ineffective and a more pragmatic approach is necessary, the authors argued.

As the average person in South Africa could have 20 close contacts per day, contact tracing is of little value, and even symptomatic cases are most infectious in the pre-symptomatic and early symptomatic phase. The fact that three quarters of the SA population were infected over the course of the first three waves demonstrates how ineffective contact tracing and quarantine is.
They recommend that certain non-pharmacological interventions should be gradually dropped, especially hand hygiene and superficial thermal screening, while outdoor events should be allowed. Rather, government focus should remain on masking in poorly ventilated spaces and ensuring proper ventilation.

Mandatory vaccinations are still on the radar, since as well as the added risk to others that unvaccinated pose, there is the greater pressure they place on the health systems when they are hospitalised for COVID.

Attention also needs to be given to the management of incidental COVID infections in hospitals. The Department of Health guidance needs to be adapted to manage these patients with the appropriate level of care for the primary reason they were admitted. And patients with severe COVID disease require additional care and expertise to improve their outcomes.

Finally, an evaluation of both vaccination status and underlying immune deficiency needs to become a key element of the workup of hospitalised patients with severe COVID.

The authors stressed the need to minimise hospitalisations and deaths, without damaging livelihoods. SA’s Omicron wave death rate is about a tenth that of Delta, on par with pre-COVID seasonal influenza deaths – 10 000 to 11 000 per annum. TB caused an estimated 58 000 deaths in 2019.

While future variants are unpredictable, there is a trend towards lower rates of hospitalisation and death, especially if vaccine coverage can be increased to 90%, particularly in the over-50 age group. Omicron’s high infection rate will likely also contribute to future protection against COVID.

They note that while there is a risk of new variants, failure to change the pandemic mindset is another risk, as Omicron signals the end of COVID’s epidemic phase.

Past practices have had little effect, the authors concluded, and it is something that the SA government appears to have realised. Despite all the severe lockdowns, SA still suffered a high COVID death rate of 481 per 100 000.

Source: The Conversation

Categories : CancerTags :

The Latest on Gastric Cancer

On By ModernMedia
Source: Pixabay

November is Gastric Cancer Awareness Month. In 2020, gastric cancer was the sixth most common cancer in 2020, with 1.09 million new cases, according to the World Health Organization.

It was also the fifth most common cause of cancer death in 2020. Gastric cancer is common in certain parts of the world, including South America and Asia. Gastric cancer can affect any part of the stomach, but in most of the world, gastric cancers form in the main part of the stomach.

Mohamad Sonbol, MD, a medical oncologist at Mayo Clinic, shares five things to know about the current state of diagnosis, screening and treatment for gastric cancer:

  • Endoscopy is usually the initial step in diagnosing gastric cancer, allowing physicians to diagnose, stage and treat some cancers at early stages. Using the endoscope, they can go in and remove localised and superficial abnormal growths. If physicians detect gastric cancer, they use a CT and positron emission tomography to scan for further staging.
  • Screening for gastric cancer is not recommended in the general population, unlike in East Asia where it is more common. However, screening protocols are in place for people at higher risk. Risk factors include obesity, smoking, alcohol consumption and family history.
  • Surgery is an option for patients whose cancer has not spread and is surgically removable. Surgery is the only curative approach for patients with localised or locally advanced gastric cancer. Other treatments, such as systemic therapy and radiation, maximise the chance of cure and lower the risk of the cancer returning.
  • New therapeutic options are available for gastric cancer. In the US, the FDA approved the combination of chemotherapy with nivolumab, an immunotherapeutic drug, in metastatic gastric adenocarcinoma. FAM-trastuzumab deruxtecan-NXKI, administered as an infusion, is now an option for patients with HER2-positive metastatic gastric cancer.

Some immunotherapeutics are standard care and some are in studies. Chemotherapy kills cells all over the body, while immunotherapy stimulates the immune system to fight the cancer. Generally, chemotherapy works for a while and then stops. When immunotherapy works, it is usually for a longer time. Which regimen to choose depends on the different targets on the cancer cells.

“I tell patients who have been recently diagnosed with gastric cancer that there is hope,” Dr Sonbol said. “We now have many more treatment options than before.”

Source: EurekAlert!

Categories : COVID Expert OpinionTags :

COVID Deaths Exceeded Worst Predictions of The Public and Most Experts

On By ModernMedia


Experts such as epidemiologists and statisticians made much more accurate predictions about COVID than the public, but both groups substantially underestimated the true extent of the pandemic, a study from the University of Cambridge has found.

Researchers from the Winton Centre for Risk and Evidence Communication surveyed 140 UK experts and 2086 UK laypersons in April 2020 and asked them to make predictions about the impact of COVID by the end of 2020. Participants were also asked to assign confidence in their predictions by providing upper and lower bounds of where they were 75% sure that the true answer would fall—for example, a participant would say they were 75% sure that the total number of infections would be between 300 000 and 800 000.

While only 44% of predictions from the expert group fell within their own 75% confidence ranges, only 12% of predictions from the non-experts fell within their ranges, though more numerate individuals performed a little better. The results were published in the journal PLOS ONE.

“Experts perhaps didn’t predict as accurately as we hoped they might, but the fact that they were far more accurate than the non-expert group reminds us that they have expertise that’s worth listening to,” said lead author Dr Gabriel Recchia from the Winton Centre for Risk and Evidence Communication,. “Predicting the course of a brand-new disease like COVID-19 just a few months after it had first been identified is incredibly difficult, but the important thing is for experts to be able to acknowledge uncertainty and adapt their predictions as more data become available.”

Expert opinion is important for those making decisions at any level from individual to policy. The quality of expert intuition can vary greatly depending on the field of expertise and the type of judgment required, so it is important to determine how good expert predictions really are, especially in where they could shape public opinion or government policy.

“People mean different things by ‘expert’: these are not necessarily people working on COVID-19 or developing the models to inform the response,” said Dr Recchia. “Many of the people approached to provide comment or make predictions have relevant expertise, but not necessarily the most relevant.” Dr Recchia noted that in the early stages of the pandemic, clinicians, epidemiologists, statisticians, and other individuals seen as experts by the media and the general public, were often asked to give off-the-cuff answers to questions about how bad the pandemic might get. “We wanted to test how accurate some of these predictions from people with this kind of expertise were, and importantly, see how they compared to the public.”

Participants in the survey were asked to predict how many people living in their country would have died and would have been infected by the end of 2020; they were also asked to predict infection fatality rates both for their country and worldwide.

The expert group and the non-expert group both underestimated the total number of deaths and infections in the UK. The official UK death toll at 31 December was 75 346. The median prediction of the expert group was 30 000, while that of the the non-expert group was 25 000.

For COVID fatality rates, the median expert prediction was that 10 out of every 1000 people with the virus worldwide would die from it, and 9.5 out of 1000 people with the virus in the UK would die from it. The median non-expert response to the same questions was 50 out of 1000 and 40 out of 1000. The true infection fatality rate at the end of 2020—as best could be estimated—was nearer to 4.55 out of 1000 worldwide and 11.8 out of 1000 in the UK.

“There’s a temptation to look at any results that says experts are less accurate than we might hope and say we shouldn’t listen to them, but the fact that non-experts did so much worse shows that it remains important to listen to experts, as long as we keep in mind that what happens in the real world can surprise you,” said Dr Recchia.

The researchers cautioned that it is important to differentiate between research on evaluating the forecasts of ‘experts’—individuals involved in relevant fields, such as epidemiologists and statisticians—and research on evaluating specific epidemiological models, though the models may inform experts. Many COVID prediction models have proved accurate in the short term, but rapidly become less accurate for later predictions.

Source: Medical Xpress

Journal information: PLOS ONE (2021). DOI: 10.1371/journal.pone.0250935

Categories : Expert Opinion Mental HealthTags :

Is PTSD Underdiagnosed or Overdiagnosed?

On By ModernMedia
Photo by Alex Green from Pexels

In an article published in the BMJ, experts debated as to whether diagnoses of post-traumatic stress disorder (PTSD) are surging in Western society due to real trauma, or whether it is simply being overdiagnosed. 

Some clinicians are concerned that diagnoses of PTSD have increased throughout Western society since the late 1980s.

PTSD is a serious and uncommon condition resulting from severe trauma, but is has come to mean an umbrella term encompassing other disorders and normal reactions to stress, argued John Tully at the University of Nottingham and Dinesh Bhugra at King’s College London’s Institute for Psychiatry, Psychology & Neuroscience (IoPPN).

Estimates of lifetime population prevalence are now around 7% in the US (26 million cases) and at 5% in other high income countries. In the UK, PTSD is estimated to be in 1 in 13 youths and in mothers after 4% of all births.

In military settings, there may be an underdiagnosis of PTSD, they acknowledged, as well as in the developing world due to limited psychiatric resources. 
But in other settings, they argue that PTSD is often conflated with normal responses to difficult situations, which has led to increased pressure on services to make this diagnosis. 

“The conflation of stress with trauma—and of trauma with PTSD—has become rife. This is the most convincing explanation for overdiagnosis,” they wrote.

This “concept creep” they argue, may also involve “compensation culture” and vested interests of the “trauma industry” as factors, they said. Am alternative explanation could be that psychiatry and society have become more accepting of trauma, and so give more leeway to diagnosis and treatment.

At a public health level however, they believe this approach is problematic as, “resources are finite, and a line must be drawn somewhere as to what level of symptoms meets criteria.”

PTSD misdiagnosis also risks other more common conditions, such as depression, anxiety disorder, and personality disorders, not being appropriately treated, while trivialising PTSD risks the medicalisation of everyday life, devaluing resilience and protective social factors, they warn.

“On this basis, we must reclaim the diagnosis of PTSD for what it is—a profound and severe response to catastrophic events—and not a spectrum of reactions to trauma or everyday life,” they conclude.

However Stephanie Lewis, Sarah Markham and Gerard Drennan at King’s IoPPN and the South London and Maudsley NHS Foundation Trust, contend that there is compelling evidence showing that PTSD is much more commonly underdiagnosed, which has concerning implications.

They say that PTSD has clear guidelines for diagnosis, and there is no evidence to suggest that it is being overdiagnosed – and rather the opposite.

“Large epidemiological studies representative of the population have found that less than half of adults and two fifths of young people who meet criteria for PTSD have sought help from any health professional,” they wrote.

“These findings fit with our professional experience that people with PTSD often find it difficult to seek help—for example, because of avoidance symptoms, concerns about stigma, or fear that there may be no effective treatment,” they write.

Additionally, only a fraction of people with PTSD who access health services receive a diagnosis, they added.

They warned that underdiagnosis is concerning because, compared to those without PTSD adults who meet the criteria are over six times more likely to attempt suicide, and 10 times for young people with PTSD. However, treatment can be effective.

They argued that underdiagnosis to PTSD should be reduced, and access increased to service for diagnosis and treatment.

“Prioritising these actions now may prove particularly timely because the COVID-19 pandemic may have exacerbated the underdiagnosis of PTSD,” they concluded.

Source: Medical Xpress

Journal information: Is PTSD overdiagnosed? BMJ (2021). www.bmj.com/content/373/bmj.n787

Categories : Diseases, Syndromes and Conditions Expert OpinionTags :

Microbes Develop Resistance to Disinfectant Too, Warns UFS Professor

On By ModernMedia

News-Medical.Net interviewed Professor Robert Bragg of the University of the Free State on the topic of pathogens, particularly bacteria, developing resistance to common disinfectants.

Professor Robert Bragg said that the control of diseases rests on three pillars: 1) vaccinations and vaccines, 2) treatment options (such as antibiotics for bacterial diseases), and 3) biosecurity.

Proff Brage explained that 10 to 15 years ago, there was an assumption that bacteria would not evolve resistance against disinfectants, but the COVID pandemic prompted a rethink. Now, disinfectant resistance is being looked at in the same light as antibiotic resistance. Biosecurity, he said, is ensuring that individuals do not come into contact with the pathogens in the first place. This is easily seen in the COVID pandemic, where face masks are worn (with a protection against contracting the disease of up to 70%), social distancing is enforced and hands and surfaces are sanitised. Though Prof Bragg’s main area of research is not antibiotic resistance, he notes that, “There are resistance mechanisms that are shared between antibiotics and disinfectants and we are looking at how these mechanisms increase resistance to disinfectants.” 

The protection of antibiotics is something taken for granted, but although mostly easily treatable (for now), bacteria can spread much faster than viruses, which require cells to reproduce in and whose re[plication rate is measured in days. “A common well-known bacterium such as Escherichia coli has a doubling time of around 20 min under ideal conditions. In other words, it only takes just 20 minutes for a population of E. coli to go from 1 million to 2 million and another 20 mins to reach 4 million, and so on,” Prof Bragg said. In the post-antibiotic era, there would be some treatment options such as bacteriophages, but for livestock the best protection would be biosecurity. However, disinfectant resistance would reduce the effectiveness of that option.

His research team has conducted a number of studies into the mechanisms of bacterial disinfectant resistance. “My research team has been working on various aspects of efficacy and resistance to disinfectants for quite some time and we have various projects that are currently underway,” he said. “Recently we identified a highly resistant strain of a Serratia species of bacteria. This strain was substantially more resistant to many different disinfectants than the reference strain. This great difference in the levels of susceptibility has allowed us to investigate various possible research mechanisms and also to look for possible novel resistance mechanisms.”

One of his team’s discoveries was that this highly resistant bacteria strain could grow on disinfectant if it was the sole source of carbon. Other areas of research around the resistant strain include sequencing and analysis of its genome, the role of bacterial efflux pumps removing disinfectant, and the role of plasmids (vehicles of genetic transfer between bacteria) in resistance and whether they are transferrable.

With regard to viruses, there are two kinds of viruses, enveloped and naked, and disinfectant has different effects on them. Enveloped viruses such as SARS-CoV-2, have a lipid layer picked up from their host cell, and are easy to kill with simple disinfectants because they break up the lipid layer, killing the cell. Naked cells are much harder to kill, and the few disinfectants that work against them are thought to do so by somehow disrupting the virus’ receptors.

One sanitiser of concern is alcohol, where 70% is considered optimal. However, people believe that ‘more is better’, yet increasing the alcohol percentage actually makes it evaporate faster, reducing contact time and thus leaving more of the virus behind. Similarly, some sanitisers include low levels of other disinfectant substances which are below the minimum threshold to kill the pathogens. This can leave surviving bacteria to develop resistance against these other sanitisers.

Prof Bragg advised that the public should purchase and use sanitisers prudently, following their instructions for use appropriately, and preferably checking to see if they are registered. He also cautioned

Source: News-Medical.Net