Category: COVID19

It is possible to avoid a second wave of Covid-19 infections by following these interventions.

Some are concerned that by easing lockdown restrictions countries will face a new wave of infections.

However, according to a new modelling study, this can be averted by simple measures.

Although there is no indication of a COVID-19 epidemic coming in waves, being sceptical may help avoid a national crisis.

People’s conduct has a serious effect on averting potential spikes or a second wave of coronavirus infections.

Simple interventions such as hand hygiene, social distancing, and wearing a face mask in crowded and enclosed public places could expel the idea of lockdowns in future.

This modelling study also shows that lockdowns should stay in place for two months to reach a peak of COVID-19 infections and then restrictions must be lifted gradually to lower a second wave risk.

Countries that forced a strict lockdown to reduce the SARS-CoV-2 transmission are now easing restrictions.

However, the process is sensitive as there is a fine line between saving the economy and fear of a second wave which might crush health care systems.

Professor Xavier Rodó, the study’s lead author, said:

“The problem is that assessing this risk is difficult, given the lack of reliable information on the actual number of people infected or the extent of immunity developed among the population.”

The projection model was based on splitting the population into seven scenarios: susceptible, quarantined, exposed, infectious not detected, reported infectious and confined, recovered, and dead.

Professor Rodó said:

“Our model is different because it considers the return of confined people to the susceptible population to estimate the effect of deconfinement, and it includes people’s behaviors and risk perception as modulating factors.”

Dr Leonardo López, the study’s first author, said:

“This model can be particularly useful for countries where the peak of cases has not yet been reached, such as those in the Southern hemisphere.

It would allow to evaluate control policies and minimize the number of cases and fatalities caused by the virus.”

The benefits of hand washing and other interventions such as social distancing have been already shown.

This study aimed to measure these behavioural interventions as infection prevention and control plans.

Their results show that as opposed to hasty deconfinement, gradually allowing life to come back to normal will reduce the infections rate and number of deaths.

Professor Rodó said:

“If we manage to reduce transmission rate by 30% through the use of face masks, hand hygiene and social distancing, we can considerably reduce the magnitude of the next wave.

Reducing transmission rate by 50% could avoid it completely.”

The results also show that even if countries don’t use coronavirus test and trace services, social empowerment like hand hygiene, social distancing, and wearing a face mask, is pivotal in preventing the spread of viruses.

Moreover, simulation results show that the longer people are immune from the disease the longer between each spike of the infection.

The study was published in Nature Human Behaviour (López et al., 2020).

The COVID-19 infection rate is 80 times higher than previously thought.

Epidemiologists think that coronavirus numbers are being under-counted as a result of asymptomatic individuals, failure to detect early cases, and testing issues.

A study now reveals that the number of early COVID-19 cases in the United States could be 80 times higher and doubling almost twice as quickly as initially thought.

They used the Centers for Disease Control and Prevention’s influenza-like illnesses (ILI) surveillance data in order to detect symptomatic cases for COVID-19 infection.

Dr Justin Silverman, the study’s first author, said:

“We analyzed each state’s ILI cases to estimate the number that could not be attributed to influenza and were in excess of seasonal baseline levels.

When you subtract these out, you’re left with what we’re calling excess ILI—cases that can’t be explained by either influenza or the typical seasonal variation of respiratory pathogens.”

The exaggerated rates for influenza-like illnesses was absolutely associated with the coronavirus transmission across the states.

Dr Silverman said:

“This suggests that ILI data is capturing COVID cases, and there appears to be a much greater undiagnosed population than originally thought.”

The excess number of ILI cases agrees with over 8.7 million new cases in three weeks in March 2020, whereas officials reported 100,000 cases for the same period of time.

Dr Silverman said:

“At first I couldn’t believe our estimates were correct.

But we realized that deaths across the U.S. had been doubling every three days and that our estimate of the infection rate was consistent with three-day doubling since the first observed case was reported in Washington state on January 15.”

Then they used the same process to measure rates of COVID-19 infection state by state.

The results showed that infection rates were much greater than originally recorded but near to those figures found after antibody tests were used in every state.

For instance, the researchers’ model shows that by the end of March about 9 percent of New York’s population was infected but after using antibody tests in the state the infection rate increased to 13.9 percent — in other word 2.7 million New Yorkers could have tested positive.

The peak of ILI numbers seems to be in the middle of March since less patients with mild symptoms needed treatment.

Also from this period all states put public health interventions in place that reduced reduced the transmission rate.

By the end of March more than half of US states had imposed stay-at-home orders or lockdowns.

Dr Silverman said:

“Our results suggest that the overwhelming effects of COVID-19 may have less to do with the virus’ lethality and more to do with how quickly it was able to spread through communities initially.

A lower fatality rate coupled with a higher prevalence of disease and rapid growth of regional epidemics provides an alternative explanation of the large number of deaths and overcrowding of hospitals we have seen in certain areas of the world.”

The study was published in Science Translational Medicine (Silverman  et al., 2020).

An indoor lamp that destroys coronaviruses in the air but is safe for humans.

UVC is an ultraviolet light which rapidly kills bacteria and viruses but is safe for use in outdoor and indoor environments.

A study has found that far-UVC light has the ability to wipe out 99.9 percent of airborne coronaviruses.

Airborne transmission refers to the presence of pathogens in small droplets that are approximately less than 10μm in diameter.

An infected person — through coughing, sneezing, or speech –produces tiny droplets containing viral particles which are infectious for hours.

Viral transmission can be either through contact by contaminated hands, touching contaminated surfaces, or by breathing the viral particles in the air (aerosols).

The possibility of SARS-CoV-2 infection via aerosols increases when an environment is poorly ventilated.

Researchers suggest that exposure to a specific ultraviolet light wavelength kills 99.9 percent of coronaviruses remaining in airborne droplets.

Professor David Brenner, the study’s lead author, said:

“Based on our results, continuous airborne disinfection with far-UVC light at the current regulatory limit could greatly reduce the level of airborne virus in indoor environments occupied by people.”

Unoccupied places including empty subway cars or empty hospital rooms, can be disinfected by conventional germicidal UVC light at 254 nm wavelength, but exposure to these lamps is dangerous to human health and can cause skin cancers.

Researchers examined different UV lamps to see which length does not cause any harm to humans and so can be used for disinfecting pathogens in occupied indoor places all the time.

Far-UVC light at wavelengths from 207 to 222 nm has been known to destroy airborne influenza viruses.

They noticed that far-UVC light at 222 nm kills airborne seasonal coronaviruses that are similar in structure to the SARS-CoV-2 virus responsible for COVID-19 infections.

The lamp doesn’t cause any harm to human eyes and skin because it can’t enter the tear film of the eye or the outer layer of skin made of dead cells.

In short, this type of light can’t reach any living cells in the human body and therefore can’t damage them.

In this study, the aerosols containing the coronavirus flowed in front of a far-UVC lamp.

A very low exposure to the lamp was enough to completely destroyed them.

It appear that an eight-minute exposure to far-UVC light would kill 90 percent of SARS-CoV-2, in 11 minutes the rate will increase to 95 percent, in 16 minutes to 99 percent, and in 25 minutes 99.9 percent of them were dead.

Professor Brenner said:

“Far-UVC light doesn’t really discriminate between coronavirus types, so we expected that it would kill SARS-CoV-2 in just the same way.

Since SARS-CoV-2 is largely spread via droplets and aerosols that are coughed and sneezed into the air it’s important to have a tool that can safely inactivate the virus while it’s in the air, particularly while people are around.”

Since the coronaviruses, as well as influenza, are sensitive to far-UVC light then this could be a practical approach to put overhead far-UVC lamps in indoor public environments.

It can dramatically lower the risk of spreading viruses from person-to-person, especially through the winter.

Professor Brenner said:

“Because it’s safe to use in occupied spaces like hospitals, buses, planes, trains, train stations, schools, restaurants, offices, theaters, gyms, and anywhere that people gather indoors, far-UVC light could be used in combination with other measures, like wearing face masks and washing hands, to limit the transmission of SARS-CoV-2 and other viruses.”

The study was published in Scientific Reports (Brenner et al., 2020).

The surprising proportion of infected people with the COVID-19 virus who show no symptoms.

A remarkable number of coronavirus patients have no symptoms of the disease at all.

Analysis of public datasets by the Scripps Research team suggest that nearly 45 percent of people carrying SARS-CoV-2 are asymptomatic.

An asymptomatic person does not show any symptoms of infection but is able to pass the virus to others for more than two weeks.

The very high percentage of asymptomatic cases most likely played a key part in the early stages of the coronavirus disease pandemic by spreading the virus silently and vigorously.

Hence, the research points out the necessity for extensive testing and contact tracing in order to reduce the spread of Covid-19 in populations.

Professor Eric Topol, the director of the Scripps Research Translational Institute, said:

“The silent spread of the virus makes it all the more challenging to control.

Our review really highlights the importance of testing.

It’s clear that with such a high asymptomatic rate, we need to cast a very wide net, otherwise the virus will continue to evade us.”

Professor Topol and his colleague gathered this data from 16 studies worldwide.

The data also includes cruise ship passengers, nursing home residents, prison inmates, among others.

Mr Daniel Oran, study’s first author, said:

“What virtually all of them had in common was that a very large proportion of infected individuals had no symptoms.

Among more than 3,000 prison inmates in four states who tested positive for the coronavirus, the figure was astronomical: 96 percent asymptomatic.”

When the team reviewed the collected information, they noticed that asymptomatic people can spread the virus for an extended time, possibly lasting beyond 14 days.

Viral load is the amount of virus present in an infected person and generally higher viral loads lead to worse outcomes.

The study found that the SARS-CoV-2 viral load in asymptomatic persons was at the same level as symptomatic patients, therefore the chance of viral transmission could be similar.

Also, just because they don’t carry any symptoms, it does not mean that there won’t be any harm.

For example, CT scans on asymptomatic patients of the Diamond Princess cruise ship show subclinical abnormalities in the lungs.

This is probably due to the impact of the SARS-CoV-2 infection on lung function despite not showing immediately.

The authors, however, admit that it is difficult to differentiate between pre-symptomatic and asymptomatic patients since long-term data and repeated testing are not available.

A pre-symptomatic individual is a person who has been infected with the virus and will sooner or later show symptoms, whereas an asymptomatic person will have silent symptoms of COVID-19 even though they are similarly infected.

Mr Oran said:

“Our estimate of 40 to 45 percent asymptomatic means that, if you’re unlucky enough to get infected, the probability is almost a flip of a coin on whether you’re going to have symptoms.”

The study was published in Annals of Internal Medicine (Oran & Topol , 2020).

A potent vaccine-like treatment against Covid-19 could swiftly protect new patients.

Powerful antibodies found in the blood of coronavirus survivors could protect patients who are in the early stage of infection.

Injection of monoclonal antibodies (mAbs) is a potential treatment against SARS-CoV-2 infection.

The treatment gives a vaccine-like protection which suppresses the severity of illness and stays long enough in patients’ blood to help the immune system getting rid of antigens.

A team from Scripps Research identified potent antibodies against the virus in patients recovered from COVID-19.

The therapy could potentially prevent the COVID-19 disease and now it is set for clinical trials.

Dr Dennis Burton, study co-author, said:

“The discovery of these very potent antibodies represents an extremely rapid response to a totally new pathogen.”

Such antibodies could be ready long before a vaccine and could give temporary vaccine-like protection to some people such as the elderly and healthcare workers as well as those patients who tested positive.

Identifying neutralising antibodies from recovered patients and then giving them to new patients has previously been successful.

The approach has been used for deadly viruses like Ebola and respiratory syncytial virus (RSV) infection, a common cause of pneumonia.

These antibodies can be manufactured in large quantities and, since they circulate in the patient’s blood for a few weeks, they last long enough to fight off the infection.

Dr Elise Landais, study co-author, said:

“We leveraged our institution’s decades of expertise in antibody isolation and quickly pivoted our focus to SARS-CoV-2 to identify these highly potent antibodies.”

The research team took antibody blood samples from recovered patients to be used in developing test cells similar to ACE2 receptors.

SARS-CoV-2 binds to these receptors to infect and destroy healthy human cells.

The team then tested these antibodies to see if they can attach to the virus and stop them from infecting the test cells.

The team found several antibodies that could protect the test cells against the infection.

The researchers say if clinical trials go well then the anti-SARS-CoV-2 antibodies would be ready by January 2021.

Dr Landais said:

“We intend to make them available to those who need them most, including people in low- and middle-income countries.”

Dr Thomas Rogers, the study’s first author, said:

“It has been a tremendous collaborative effort, and we’re now focused on making large quantities of these promising antibodies for clinical trials.”

In addition to identifying anti-SARS-CoV-2 antibodies the team found a neutralising SARS-CoV antibody.

SARS-CoV is the virus responsible for the severe acute respiratory syndrome (SARS) outbreak in Asia during 2002 to 2004.

Dr Burton  said:

“That discovery gives us hope that we will eventually find broadly neutralizing antibodies that provide at least partial protection against all or most SARS coronaviruses, which should be useful if another one jumps to humans.”

The study was published in the journal of Science (Roger et al., 2020).

There is a two-way relationship between COVID-19 and diabetes.

Coronavirus could cause diabetes in previously healthy patients and also lead to serious complications of pre-existing diabetes, such as a hyperosmolar hyperglycemic state, evidence shows.

Hyperosmolar syndrome is a condition triggered by an infection or illness in diabetics who have extremely high blood sugar.

Clinical cases reported a two-way relationship between diabetes and COVID-19.

We now know that diabetes increases the odds of severe illness and death from coronavirus.

About 30 percent of COVID-19 patients who died have been found to be diabetics.

On the other hand, experts from the CoviDiab Registry project say that individuals who are infected by SARS‐CoV‐2 could develop diabetes and its life-threatening complications.

Although it is not completely clear yet how the virus affects diabetes, a study has revealed that SARS-Cov-2 will enter human cells by binding to ACE2.

ACE2, which is a protein-coding gene, is located in the human tissues, lungs, heart, arteries, and other organs such as liver, pancreas and kidney and is involved in a process that breaks down glucose (blood sugar) to energy.

When the virus enters these organs it probably causes serious abnormalities and disruption to this process, as for years it has been thought that virus infections can cause type 1 diabetes.

Professor Francesco Rubino, lead investigator of the CoviDiab Registry project, said:

“Diabetes is one of the most prevalent chronic diseases and we are now realizing the consequences of the inevitable clash between two pandemics.

Given the short period of human contact with this new coronavirus, the exact mechanism by which the virus influences glucose metabolism is still unclear and we don’t know whether the acute manifestation of diabetes in these patients represent classic type 1, type 2 or possibly a new form of diabetes”.

Professor Paul Zimmet, co-investigator of the CoviDiab Registry project, said:

“We don’t yet know the magnitude of the new onset diabetes in COVID-19 and if it will persist or resolve after the infection; and if so, whether or not or COVID-19 increases risk of future diabetes.

By establishing this Global Registry, we are calling on the international medical community to rapidly share relevant clinical observations that can help answer these questions”.

Professor Stephanie Amiel, co-investigator of the CoviDiab Registry project, said:

“The registry focuses on routinely collected clinical data that will help us examine insulin secretory capacity, insulin resistance and autoimmune antibody status to understand how COVID-19 related diabetes develops, its natural history and best management.

Studying COVID-19-related diabetes may uncover novel mechanisms of disease.”

The study was published in the New England Journal of Medicine (Rubino et al., 2020).

A widely available medicine could save one-third of patients hospitalised with COVID-19.

One-third of coronavirus patients who are seriously ill and suffering from severe respiratory complications can be saved with a common steroid treatment.

Dexamethasone is a corticosteroid, which is a class of steroid hormone that works as an anti-inflammatory.

A study called the RECOVERY trial tested this cheap and readily available drug on COVID-19 patients.

They found that dexamethasone saved one-third of patients who were on ventilators and reduced deaths by a fifth for patients receiving oxygen.

Researchers say, due to its low cost, it could also benefit poorer countries.

They believe it can be used right away to save many lives of seriously ill patients with COVID-19 worldwide.

Professor Martin Landray, the study’s lead researcher, said:

“Since the appearance of COVID-19 six months ago, the search has been on for treatments that can improve survival, particularly in the sickest patients.

These preliminary results from the RECOVERY trial are very clear – dexamethasone reduces the risk of death among patients with severe respiratory complications.

COVID-19 is a global disease – it is fantastic that the first treatment demonstrated to reduce mortality is one that is instantly available and affordable worldwide.”

In this trial, 2,104 patients received a daily dosage of 6 mg of dexamethasone for ten days.

The highest death rate was amongst those patients on ventilators, intermediate for those needing oxygen, and lowest for those patients who didn’t need any respiratory support.

Dexamethasone cut the risk of death in ventilated patients from 40 percent to 28 percent compared with those who were not on dexamethasone.

It also reduced the risk of death from 25 percent to 20 percent in other patients who were on oxygen.

However, dexamethasone treatment didn’t benefit those patients who didn’t need respiratory interventions, suggesting it helps prevent death only in seriously ill patients.

Professor Peter Horby, a principal investigator for this trial, said:

“Dexamethasone is the first drug to be shown to improve survival in COVID-19.

This is an extremely welcome result.

The survival benefit is clear and large in those patients who are sick enough to require oxygen treatment, so dexamethasone should now become standard of care in these patients.

Dexamethasone is inexpensive, on the shelf, and can be used immediately to save lives worldwide.”

Dexamethasone, due its anti-inflammatory effects, is usually prescribed for conditions such as patients with asthma, skin problems, and arthritis.

It is probable that it prevents the immune system from overreacting, which is known as cytokine storm.

Cytokine storm is seen in patients with respiratory diseases, flu, and COVID-19.

At the moment, US doctors suggest caution over the ‘breakthrough’ claims on dexamethasone and want to see the complete published results and understand potential side-effects in order to make a decision.

The results come from the RECOVERY (Randomised Evaluation of COVid-19 thERapY) trial, which is not published yet.

But are the antibodies produced enough to block reinfection?

All patients recovered from coronavirus disease develop a neutralizing antibody (NAb) that keeps the virus ineffective, new research finds.

However, the levels may not be adequate in everyone to guarantee they won’t be reinfected.

The immunological study on 149 recovered COVID-19 patients suggests that the immune system is able to produce antibodies but the levels are different in everybody.

Despite the wide variation in antibody levels in recovered patients, many had developed some natural immunity to fight the SARS-CoV-2 virus.

Some antibodies are more effective than the others.

Although many can attach onto the surface of the virus and inactivate it, only some antibodies are absolutely capable of neutralising the infectious agent by blocking it from invading cells.

Professor Michel C. Nussenzweig, study co-author, said:

“This suggests just about everybody can do this, which is very good news for vaccines.

It means if you were able to create a vaccine that elicits these particular antibodies, then the vaccine is likely to be effective and work for a lot of people.”

The neutralising effect couldn’t be detected in 33 percent of people.

It is possible that their immune systems dealt with the infection before the cells that produce antibodies got involved.

Most individuals had small quantities of neutralising antibodies and only 1 percent showed high neutralising activity.

Dr Davide Robbiani, the study’s first author, said:

“Like in other diseases, everyone responds differently.

Some people have poor response, some average.

And then there is a fraction of people that are exceptional responders.”

The 1 percent of exceptional or “elite” responders are important as there is a chance that experts could identify the rare immune cells that produce them.

Then they would be able to duplicate the antibodies from these cells and produce a drug that can mimic the same robust defence in other humans.

Various antibodies are generated by elite responders but 40 antibodies were responsible for neutralizing the virus in which three specific antibodies were shown to be the most powerful ones against COVID-19.

The researchers are now focusing on these three antibodies for further development of drugs in treating or preventing the coronavirus infection.

Dr Robbiani said:

“We now know what an effective antibody looks like and we have found similar ones in more than one person.

This is important information for people who are designing and testing vaccines.

If they see their vaccine can elicit these antibodies, they know they are on the right track.”

The study was published in BioRxiv (Robbiani et al., 2020).

Study reveals how warmer weather may affect the transmission of COVID-19.

During summer the transmission rates of most respiratory viral infections such as influenza will drop.

Several studies on SARS-CoV-2  have shown that its survival rate is shorter in higher temperatures and UV light inactivates the virus.

However, until now the effects of temperature, UV light, and precipitation on how quickly the virus is transmitted between people has not been investigated.

The question is whether warmer temperature, UV light, and humidity can lower or even curb the rapid spread of SARS-CoV-2.

A research team assessed the link between weather conditions including precipitation, UV index, and temperature and the number of coronavirus cases during spring 2020 in the U.S.A..

They found that higher temperature up to 52 degrees Fahrenheit (11 degrees Celsius) reduced the incidence of COVID-19.

However, any higher temperatures didn’t have much impact on reducing disease transmission.

Precipitation patterns didn’t affect the spread rate but a higher UV index was found to lessen the number of new cases.

Dr Shiv T Sehra, the study’s first author, said:

“While the rate of virus transmission may slow down as the maximum daily temperature rises to around 50 degrees, the effects of temperature rise beyond that don’t seem to be significant.

Based on our analysis, the modest association suggests that it is unlikely that disease transmission will slow dramatically in the summer months from the increase in temperature alone.”

Furthermore, they checked if changes in temperature had any impact on the spread of SARS-CoV-2 between January and April 2020.

They used a model for five different scenarios as follows: above 60 degrees °F (16 °C), between 50-60 degrees °F (10 °C – 16 °C), between 40-50 degrees °F (4 °C – 10 °C), between 30-40 degrees °F (-1 °C – 4 °C), and less than 30 degrees °F (-1 °C).

The days that the temperature was above 50 degrees °F showed the lowest number of new COVID-19 cases.

While the days where the temperature was below 30 degrees °F had the maximum hike in infection rates.

According to The Centers for Disease Control and Prevention, through the fall and winter as temperatures drop the coronavirus pandemic might get worse.

Dr Sehra noted:

“Our results are in line with those predictions.

We also caution that the disease may get worse in the fall and winter months.”

One study limitation is that the collected data reflect spring when the daily maximum temperature was below 70 degrees Fahrenheit (21 degrees Celsius) whereas summer temperatures in most parts of the country will be much higher than that.

Consequently, this study can’t assess the possible effects of temperatures above 70-75 degrees Fahrenheit on COVID-19 virus transmission.

The study was published in the journal Clinical Infectious Diseases (Sehra et al., 2020).