Tag: covid

AI Solutions Are No Magic Bullet Against COVID

A leading researcher in the field of medical image analysis has cautioned against the rush to provide AI solutions to the COVID pandemic, arguing that the need to help out must not compromise scientific principles.

Prof Hamid Tizhoosh, head of KIMIA Lab, Faculty of Engineering at the University of Waterloo wrote a piece on Medical-News.Net where he laid out the problems involved in such “quick fix” solutions.

He explains that AI researchers often make “toy” datasets which they use to experiment with in their own labs. In the middle of the pandemic, it is difficult to collaborate with radiographers who have their hands full dealing with COVID patients’ images.

AI research requires the acquisition and curation of large amounts of high-quality data, and currently there is an absence of this. While there are still few publicly available X-ray images or CT images of COVID patients’ lungs, they are beginning to crop up on the internet. AI researchers and enthusiasts are scraping together these images for their data sets and supplementing them with those of pneumonia patients, which are much more readily available. The results of their AI work are being released in papers that are not peer reviewed, yet some claim to be authoritative solutions.

Tizhoosh draws attention to the validity of this data. In one instance, he saw that the data included a pneumonia case from a paediatric patient. He cautions that, “AI is neither a ventilator nor a vaccine nor a pill; it is extremely unlikely that the exhausted radiologists in Wuhan, Qom or Bergamo download the Python code of our poorly trained network (using insufficient and improper data and described in quickly written papers and blogs) to just obtain a flawed second opinion.”

He concludes that the AI developments must come after appropriate images are made available by hospitals, that ethics approval is received and the data is properly de-identified.

Netcare CEO Recounts Challenges and Lessons of 2020

In an interview posted on Moneyweb, the CEO of Netcare, Dr Richard Friedland, related how the company had weathered a very hard financial year.

“We have certainly felt the effects financially and we haven’t been able to pay a dividend to shareholders. But, as I’ve said to all of our frontline workers, we paid a dividend to South Africa in terms of looking after so many thousands – more than 28 000 Covid patients. That is far more significant than anything we could have done in monetary terms,” said Friedland.

The company learned valuable lessons, being at “the tip of the spear” of the COVID pandemic. Following their first cases on March 9, a large outbreak occurred at St Augustine’s, followed by a much smaller one at Kingsway. 

Friedland spoke of the sacrifices the staff had made over the past months, saying “This is not a time to abandon them. It’s a time to stand with them. It does mean our recovery will be longer, but we’ll do that together. And I think it’s critically important, given the headwinds we’re facing in South Africa.”

The company made much of its profit from asset disposal, but Friedland said that they were seeing a return to demands for elective surgery, excepting their two hospitals in the Nelson Mandela Bay area. He noted that there was a noticeable uptick in cases, similar to what they had experienced in the first wave, and that their hospitals were relatively full. However, they were putting their lessons learned into practice by having readied adequate stores of PPE and oxygen, for example. The length of stay has been reduced from 22 days to seven. He remarked on how stressful the pandemic had been for all concerned, but he said that continued efforts must be made.

“[…]Covid nearly robbed us of our humanity, and we need to be very careful about that going forward, particularly as healthcare workers, when patients cannot see their loved ones, when they’ve got to communicate with us through masks and spaces. We’ve managed to find other ways, through Facetime and mobiles, to communicate with their loved ones; but there’s no excuse for [not] improving communication all the time. I think Covid exposed that and there’s been a lot of anxiety as a result that we still need to manage,” concluded Friedland.

Effectiveness of COVID Government Interventions Compared

Currently, the most widely used tool to deal with the spread of COVID are non-pharmaceutical interventions (NPIs), which involve measures such as social distancing. In the face of the sudden emergency of the COVID pandemic, governments around the world implemented a wide range of NPIs, some based on scientific advice and some not. The effectiveness of these government interventions is compared in a new study.

In order to evaluate the effectiveness of these responses, researchers studied government interventions across 79 countries and territories. Each item was ranked, making a comprehensive dataset of 6068 interventions and compared to the reproduction number, Rt. They were analysed with four computational methods, including machine learning.

The study found that the most effective interventions were those that restricted movement such as travel restrictions and lockdowns, as well as social distancing. Cancellations of gathering also seemed to be effective. The least effective were appeals for international aid, tracking and tracing, disinfecting surfaces had the least impact.

Interventions also had differing effectiveness depending on what stage of the pandemic they were implemented in.

The most consistently effective intervention across all locations was contact tracing and quarantine.

Source: News-Medical.Net

COVID and Vaping Lung Injuries can be Confused

Three recent case studies show that breathing problems in teens could be a result of vaping or COVID, according to a UC Davis Health paediatric team.

Known as e-cigarette, or vaping, product use-associated lung injury (EVALI), it is present in large numbers. As of February 2020, 2758 cases of EVALI were hospitalised, with 64 deaths in the United States, and over half of those hospitalised were under 25 years old.

“EVALI and COVID-19 share many symptoms but have very different treatment plans,” said lead author Kiran Nandalike, associate professor of paediatrics. “For this reason, providers caring for pediatric patients with unexplained respiratory failure should consider EVALI and ask for relevant smoking/vaping history.”

EVALI and COVID patients often present with fever, cough, nausea, abdominal pain and diarrhoea. Bilateral ground glass opacities are seen in chest imaging in both conditions.

Adolescents often use vaping with marijuana obtained through friends, family and unlicenced dealers, with products often containing vitamin E acetate, an additive which is strongly associated with lung injury. Isolation and stress as a result of the COVID pandemic increased usage.

In the case studies, all of the patients had fever, nausea and cough, as well as a high heart rate, rapid breathing and low blood oxygen levels. Laboratory results showed higher white blood cells (WBC) count and elevated inflammation, pointing to COVID inflammation. Chest imaging revealed nonspecific ground glass opacities. Despite all other findings indicating COVID, SARS-CoV-2 testing was negative. The patients were successfully treated with steroids, a potentially life-saving treatment for EVALI.

“To help reduce risk of EVALI recurrence, providers would recommend vaping cessation counseling to patients and close outpatient monitoring,” advised Nandalike.

Source: Medical Xpress

COVID Most Infectious Early On, Says New Review

According to a meta-analysis of COVID research published in The Lancet, individuals with COVID are most infectious early on.

In a meta-analysis of 79 studies from around the world, they examined viral load dynamics, duration of viral RNA shedding, and viable virus shedding for SARS-CoV-2, and for comparison, 8 studies on MERS-CoV and 11 on SARS-CoV. The study only looked at symptomatic individuals.

For SARS-CoV-2, the average duration of viral RNA shedding was 17 days in the upper respiratory tract and 14.6 days in the lower respiratory tract. Similar durations were found for stool (17.2 days) and serum samples (16.6 days). 

The maximum duration of viral RNA shedding was 83 days in the upper respiratory tract, 59 days in the lower respiratory tract and 126 days in stools.  No role could be discerned for faecal shedding. Average shedding duration was positively correlated with age. No studies detected live virus after 9 days.

The viral load in the upper respiratory tract reached a peak in the first week of illness, which was shorter than SARS-CoV (peaking at days 10-14) and MERS-CoV (days 7-10). Most studies indicated faster viral load clearing in asymptomatic versus symptomatic SARS-CoV-2 carriers.

In view of these findings, the researchers suggest that repeat testing may not be necessary for patients no longer deemed infectious, and that isolation could be set for 10 days after the onset of symptoms.

The researchers concluded that early containment was key in fighting the spread of COVID, especially with regard to acting on atypical symptoms that might appear before other symptoms. Still, this could prove challenging to effect in practice. 

Source: The Lancet

Controversial Study: Cloth Masks Don’t Prevent Catching COVID

In a controversial result, researchers in Denmark have shown real-world evidence that masks do not protect against becoming infected with COVID.

4860 participants completed the study in Denmark, which at the time had a 2% infection rate. Half received surgical masks and were told to wear them outside while the other half were told not to wear masks. The researchers had hoped to see the masks halving the infection rate among wearers, but 1.8% of mask wearers became infected with COVID vs 2.1% of non-mask wearers.

“Our study gives an indication of how much you gain from wearing a mask,” said lead author Dr Henning Bundgaard, a cardiologist at the University of Copenhagen. “Not a lot.”

The results were met with scepticism by some, and noted that the lower prevalence of COVID in Denmark at the time made differences hard to detect.

Dr Thomas Frieden, chief executive of Resolve to Save Lives, an advocacy group, and former director of the CDC outlined the limitations of the study, saying, “There is absolutely no doubt that masks work as source control. The question this study was designed to answer is: Do they work as personal protection?” Frieden said that the answer to those questions lay in the amount of virus exposure and the nature of the masks involved.

“An N95 mask is better than a surgical mask,” he said. “A surgical mask is better than most cloth masks. A cloth mask is better than nothing.”

Dr Christine Laine, editor in chief of the Annals of Internal Medicine, characterised the evidence that masks were protective of wearers as weak.

“These studies cannot differentiate between source control and personal protection of the mask wearer,” she said. 

She added that the new study reinforced the need for other methods, such as social distancing. Masks “are not a magic bullet,” she said. “There are people who say, ‘I’m fine, I’m wearing a mask.’ They need to realise they are not invulnerable to infection.”

Source: Japan Times

COVID Antibodies in Children without the Disease

One case in Australia of children producing COVID antibodies while being exposed to their parents were ill with the disease has shed light into the way children appear to remain largely unaffected by it.

The parents of three children fell ill after attending a wedding, developing COVID with all the normal symptoms. Fortunately, they did not require hospitalisation but the whole family was tested for COVID. To the amazement of clinicians, the test for all three children came back negative, as did a subsequent re-test. The two older children had mild symptoms of COVID.
“It was jaw-droppingly amazing because they’d spent a week and a half with us while we were COVID-positive,” said their mother, Leila Sawenko.

Intrigued, researchers asked the family to come back for a series of tests. While polymerase chain reaction (PCR) tests failed to detect SARS-CoV-2, saliva samples showed SARS-CoV-2 antibodies. The children’s cytokine levels remained low, consistent with their lack of symptoms. 

Researchers believe that, unlike their parents, the children’s immune system staged such an effective response that viral replication was severely restricted. 

“The discordance between the virological PCR results and clinical serological testing, despite an evident immune response, highlights limitations to the sensitivity of nasopharyngeal PCR and current diagnostic serology in children,” wrote the researchers.

Source: Science Alert

Many HIV Deaths in Africa Due to Interrupted Care

An article written for The Conversation explores the reasons why, in an era of antiretroviral therapy (ART), so many people around the world are still dying of HIV.

Despite fierce resistance under Thabo Mbeku’s leadership, ART became widely available in South Africa. Yet in 2019, despite the world’s largest ART programme with 71% coverage, there were still 72 000 HIV-related deaths in South Africa. 

Medecins Sans Frontieres (MSF) supports hospitals across Africa in treating people with HIV, but because patients present with advanced HIV up to a third die during their hospital stay.

HIV is a lifelong disease, and requires lifelong treatment. Some struggle to take tablets on a daily basis, risking drug resistance.

People with advanced HIV now typically have interrupted or failing treatment. MSF-funded studies in Kenya and the DRC showed that only 20-35% of patients with advanced HIV had never received ART.

The “Welcome Back Services” provided by Medecins Sans Frontieres in Khayelitsha, Cape Town are an example of getting patients who have lapsed back into care.

In deprived settings, TB is the leading cause of death for people with HIV, along with cryptococcal meningitis and bacterial infection. These are all treatable if caught in time; cryptococcal meningitis effectively has a zero survival rate but mortality can be reduced by 40% when treated with flucytosine and amphotericin B. By testing patients before they reach the stage where hospitalisation is necessary, survival rates can be greatly improved.

Weight Link to COVID Risk Emphasised by CDC

The Centers for Disease Control and Prevention (CDC) in the US has included in its coronavirus risk warning people who are considered overweight (a BMI of 25 to 29.9, obese is above 30).

Dr Donald Hensrud, director of the Mayo Clinic Healthy Living Program, explained that obesity already is associated with several complications – diabetes, high blood pressure, dyslipidaemia and cardiovascular disease.

Dr Hensrud said, “Now COVID-19 comes along, and we’ve got all the issues we had before plus some additional ones. Obesity is associated with low-grade inflammation and an effect on our immune system. This affects our susceptibility to COVID-19. People who are obese are more likely to develop COVID-19 and complications from it, including dying, than people who aren’t obese. In addition, people with diabetes and some of the other complications from obesity are also at increased risk. So obesity and its complications independently take the risks of COVID-19 and elevate them significantly.”

Dr Hensrud said that he noted patients of his had put on weight during lockdown due to comfort eating and staying at home without any exercise. In order to reduce their risk, people should resolve to eat a healthy diet and engage in exercise, although he cautioned that losing more than 10% body weight in six months can impact the immune system.

Source: Medical Xpress

Elon Musk Says He May Have COVID

Elon Musk, CEO of SpaceX and Tesla tweeted that he may have COVID, according to Bloomberg.

The 49 year old tech entrepreneur said that so far his symptoms resemble those of a cold. He took four rapid antigen tests, which are cheaper and faster but two of them came back as negative and two came back as positive. He commented that these results were “extremely bogus”.

No stranger to courting controversy, Musk has in the past cast doubts about COVID, even claiming in March that there would be “zero” cases in the United States by April (which currently has recorded 153 496 new daily cases as of writing this article). He then appeared to cast further doubts, saying that the number of cases would “explode” due to the number of false positives.