CMAAO Coronavirus Facts And Myth Buster: COVID-19 Update

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With inputs from Dr Monica Vasudev

1035: An analysis of primary human lung cells that were infected in the lab with SARS-CoV-2 revealed how the cells accumulated large amounts of lipid droplets. Following infection, the lung proteins downregulate the ability of lung cells to burn carbohydrates and fatty acids. Lung cells cannot hold fat. This could possibly explain some of the severe damage that is done to the lungs of patients with COVID-19. The virus depends on glucose uptake, cholesterol production, and fatty acid oxidation. Additional research is needed on the cholesterol drug fenofibrate before clinical trials can start.

1036: The antihistamine cloperastine, mostly sold in Japan, tends to block glucose uptake in lung cells and has shown some effect in fighting COVID-19.

1037: Moderna’s experimental COVID-19 vaccine led to a strong immune response and provided protection against infection in monkey study. The vaccine, MRNA-1273, when given to non-human primates provided protection against infection in the lungs and nose, and prevented pulmonary disease. Results of the study were published in the New England Journal of Medicine.

It appears to be an improvement over the results of AstraZenecas COVID-19 vaccine in a similar study. This study included 24 monkeys, where Moderna tested 10 micrograms or 100 micrograms of the vaccine against no treatment.

Both doses were found to be effective in protecting against viral replication in the lungs and lung inflammation. The larger dose also protected against viral replication in the nose of the animals.

1038: A vaccine being developed by AstraZeneca and Oxford University is among the most advanced in human trials. In a similar animal study, this vaccine also appeared to prevent damage to the lungs and prevent the virus from replicating. However, the virus actively replicated in the nose.

1039: A cohort of 145 patients below 1 month to 65 years separated by age noted that the youngest children had significantly lower median cycle threshold (CT) values compared to older children or adults. This indicated that they had equivalent or more viral nucleic acid in their upper respiratory tract than other age groups. These differences amounted to a 10- to 100-fold greater amount of SARS-CoV-2 in the nasopharynx of young children, noted the authors in a research letter in JAMA Pediatrics. However, these findings were limited to detection of viral nucleic acid and not infectious virus.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

The Sound of Coronavirus

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Reproduced from: India Legal, https://www.indialegallive.com/cover-story-articles/focus/the-sound-of-coronavirus,August 1, 2020

New breakthrough technologies have been found by Israeli scientists to initially test for the virus while avoiding going to a lab. These include testing breath, saliva and voice samples

Testing is a critical part of the “test, trace and isolate” strategy to contain Covid-19. But an end seems nowhere in sight. Cases continue to rise globally including in India. The gold standard test for the diagnosis of the SARS-CoV-2 virus is RT-PCR. Specimens used for the test are nasopharyngeal or oropharyngeal swabs. However, there are some drawbacks associated with their use. Shortage of skilled staff and/or good quality collection kits or viral transport medium, high costs, sampling errors (leading to false-negative results), patient fear and anxiety are some of them. Healthcare workers are also at great risk of infection due to the production of aerosols during the sampling.

Hence, scientists the world over are engaged in research to develop economical alternatives to rapidly and accurately diagnose cases of Covid-19. Some of these tests are:

Saliva test: PCR testing on saliva has recently been suggested as a convenient and cost-effective alternative to RT-PCR to detect the SARS-CoV-2 virus. Use of saliva-based testing offers several advantages—collection is easy and can be done with minimum discomfort to the patient during sampling; it is non-invasive and does not need a skilled healthcare worker to collect, can be done at home by people themselves without travelling to a hospital or testing lab, minimises the risk of cross-infection and reduces the use of PPEs and swabs, especially where there is a shortage. It may particularly be useful in children where a nasal swab may be difficult to obtain (deviated septum) or those who need to undergo repeated tests.

However, saliva tests may be less sensitive in detecting Covid-19. Preliminary data from a meta-analysis of trials found 91 percent sensitivity for saliva tests and 98 percent for nasopharyngeal swab tests in previously confirmed infected patients. This means that saliva may have lower concentrations of the virus compared to swabs.

Social engineering: This screening is cheap and can be done at home by everybody. It involves checking a person at the entry of the house or the office with five basic things. The person is first offered a welcome dish of jaggery to eat and if he can taste the sweetness, it means he does not have loss of taste. Then he is offered a rose and if he can smell it, it means there is no loss of smell. After that the temperature is checked and SpO2 (blood oxygen saturation) levels after walking. If these are normal, then the strength of the patient’s hand grip is seen and if that too is normal, then it means he is neither asymptomatic nor symptomatic at that particular time.

Voice-based analysis: We can know from the voice if a person has a cold. Doctors have for long relied on the sounds of heart beats, respiration and bowel to diagnose diseases. They have used the quintessential signature tool of the doctor—the stethoscope—to do this. Now the smartphone too can be used to screen patients for Covid-19. The use of sound to detect Covid-19 infection is an upcoming technology.

Researchers from Israel are working to use artificial intelligence to analyse the voice of a person to see if he has the infection. The technology will correlate the voice with the symptoms of Covid-19 and issue an alert. If available, it would be a contact-free, non-invasive screening method. Since it would be available on a smartphone, it can be self-administered and should not take longer than a few minutes. But this would only be a screening method and not a diagnostic tool, so it would not be a substitute for confirmatory laboratory tests. Moreover, its reliability as a screening tool also needs to be tested. It seems to be an exciting prospect, but time will tell.

Virus detectors: These use radio waves on a breath sample and work like a breath analyser. One needs to breathe into a tube which is then put into a machine which uses terahertz radio frequencies and an algorithm to see if the virus is present. It generates a result within 60 seconds. Individuals perform the test by taking a deep breath and then exhaling into a tube three times. The presence of the coronavirus within the exhaled breath aerosols is determined based on recognition of its spectral signature. In addition to the benefit of providing an immediate result and avoiding any laboratory processing, the test eliminates the need for skilled individuals to obtain the sample and swabs, which have been in limited supply in some areas.

According to one of the researchers, the breathalyser test may also detect the virus within the first four days after initial exposure. This is the window of time when results from polymerase chain reaction testing may be inaccurate. The developers believe that by identifying people who are not carrying the SARS-CoV-2 virus, the test will allow workers to return to their jobs and thereby assist in mobilising the economy. They describe the breathalyser test as “the new thermometer”.

An Israeli company which is developing the breathalyser test has called it a “front line” tool that can help restore a sense of normality during the pandemic. NanoScent, the firm making the test kits, said an extensive trial in Israel for the presence of live virus delivered results with 85 percent accuracy, and the product could receive regulatory approval within months. Chief Executive Officer Oren Gavriely reportedly said that the breathalyser would not replace lab tests but was a mass screening tool that could help people gain “the confidence to go back and act as normal”.

Using a watch: Many digital watch companies are also trying to assimilate the measurements of temperature, heart rate and SpO2 monitor in smart watches or smart wrist bands to pick up early cases.

Necessity is the mother of invention here.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

CMAAO Coronavirus Facts and Myth Buster: COVID Update

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With inputs from Dr Monica Vasudev

1031: Can Trained Dogs Identify COVID-19 Infections?

Following some training, dogs may be able to sniff out and spot the individuals infected with the coronavirus, revealed a study published in BMC Infectious Diseases.

This was a small pilot project tested by the German Armed Forces, the University of Veterinary Medicine in Hannover and the Hanover Medical School.

Eight dogs who were part of the German Armed Forces, were trained for a week to identify the virus in samples of saliva. This was followed by giving them over 1,000 infected and non-infected samples. The dogs could detect 94% of cases. They were able to correctly identify 157 positive samples and 792 negative samples; however, they missed 30 positive samples and gave false positive finding for 33 samples.

Dogs cab detect a specific smell of the metabolic changes that occur in those patients. Trained dogs could be sent to airports, sporting events, etc., to detect infections.

Dogs have previously been trained to detect cancer, malaria, and other bacterial and viral infections. [Medscape]

Cardiovascular effects of COVID-19

As per a study published in JAMA Cardiology, cardiac inflammatory involvement is frequently seen among patients who have recently recovered from COVID-19 infection, irrespective of pre-existing conditions. In a cohort of 100 German patients who had recently recovered from the infection, cardiovascular magnetic resonance (CMR) revealed cardiac involvement in 78% and ongoing myocardial inflammation in 60%.

Cardiac involvement was seen regardless of infection severity, overall course of COVID-19 presentation, time from the original diagnosis, or the presence of cardiac symptoms.

This was a prospective observational study including patients who had recovered from COVID-19 from April through June 2020. The participants were at least 2 weeks out from being diagnosed with COVID-19, and their respiratory symptoms had resolved; they had negative results on a swab test at the end of the isolation period.

Fifty three patients were male, with a median age of 49 years. The median time interval between COVID-19 diagnosis and CMR was 71 days. Of the patients, 67 recovered at home, and 33 needed hospitalization. Pre-existing conditions among the patients included hypertension, diabetes, and known coronary artery disease, but no previously known heart failure or cardiomyopathy. Pre-existing conditions were similar between patients who recovered at home and those who were hospitalized.

At the time of CMR, 71 patients had detectable high-sensitivity troponin T (hsTnT) (≥3 pg/mL) while it was significantly elevated (≥13.9 pg/mL) in 5 patients. Patients recently recovered from COVID-19 had lower left ventricular ejection fraction, higher left ventricle volumes, higher left ventricle mass, and elevated native T1 and T2 compared to the control groups.

Myocardial inflammation was the most common abnormality observed on CMR , defined as abnormal native T1 and T2 measures. It was evident in 73 and 60 patients, respectively. This was followed by regional scar and pericardial enhancement, which was evident in 32 and 22 patients, respectively. Findings on classic parameters, such as volumes and ejection fractions, were mildly abnormal.

A small but significant difference could be observed in native T1 mapping between patients who recovered at home compared to those who were hospitalized (median, 1122 ms vs 1143 ms; P = .02), but not for native T2, hsTnT, or N-terminal pro-b-type natriuretic peptide levels. None of these measures correlated with time from COVID-19 diagnosis.

Levels of hsTnT significantly correlated with native T1 mapping (P < .001) and native T2 mapping (P = .03). A cross-correlation was also seen between native T1 and T2 (P < .001). There was a significant correlation of hsTnT with native T1 (P < .001) and left ventricle mass (P < .001). The associations of hsTnT with mapping measures were significant even after controlling for the presence of comorbidities (overall or separately) or treatment received for COVID-19 infection.

Unlike the previous studies, the findings in this study indicate that significant cardiac involvement occurs independently of the severity of original presentation and persists beyond the period of acute presentation. Additionally, there is no significant trend toward reduction of imaging or serological findings during the recovery period. [DG alert]

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

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