LIVE BLOG: R&D response to COVID-19 pandemic (archived)

One of the first studies to document the impact of COVID-19 on already existing viruses in Australia has shown the pandemic was responsible for creating a huge change in the incidence and genetics of Respiratory Syncytial Virus (RSV) in the country.

RSV is a common virus that generally causes mild, cold like symptoms but the infection can be serious for infants and older adults.

The researchers say the pandemic disrupted the seasonal pattern of RSV, which is one of the regular ‘winter viruses’. For the first time on record, in 2020 there was no winter RSV epidemic, which is attributed to COVID-19 travel restrictions and infection control measures.

However, RSV was one of the first of the key respiratory pathogens to re-emerge after COVID-19.

The researchers genetically sequenced major outbreaks of RSV occurring out of season over the summer of 2020-21 on both sides of the country. These outbreaks coincided with the easing of COVID-19 control measures.

They found there had been a major collapse in RSV strains known before COVID-19, and the emergence of new RSV strains. These new strains dominated each outbreak in Western Australia, New South Wales and the Australian Capital Territory.

The researchers then tracked the seeding of viruses from each outbreak into Victoria, which led to another major RSV outbreak.

“Our genetic studies showed that most of the previous RSV strains had gone ‘extinct’ and that for each outbreak only a single genetic lineage had survived all the lockdowns,” said lead researcher John-Sebastian Eden, senior research fellow at the University of Sydney Institute for Infectious Diseases.

The study raises important questions as to how rapid spread and evolution of RSV could inform the re-emergence of other viruses including influenza.

“The constellation of flu strains circulating pre and post-COVID-19 has also changed a lot, leading to challenges in how we choose the composition and timing of our annual vaccines. For example, the flu season in Australia has kicked off much earlier than in previous years.” said Eden.

There is currently no approved RSV vaccine, but it is a major focus for vaccine and therapeutic development.

“We need to be vigilant – some viruses may have all but disappeared, but will likely rebound in the near future, possibly at unusual times and with stronger impact,” Eden said. “We need to be prepared for large outbreaks of RSV outside of normal seasonal periods.”

Before COVID-19, two major RSV subtypes, A and B, co-circulated at similar levels.

During late 2020 to early 2021 during the outbreak periods, this changed dramatically. The RSV-A subtype was found to be the dominant strain – making up more than 95% of cases in all the states. The RSV-B had all but disappeared.

A new computer-aided diagnostic tool could help overcome some of the challenges of monitoring lung health following infection with COVID-19.

In common with other respiratory illnesses, COVID-19 can cause lasting harm to the lungs. However, it is hard to visualise this damage because conventional chest scans do not reliably detect signs of lung scarring and other pulmonary abnormalities. That is making it difficult to track the health and recovery of people with persistent breathing problems and other post-COVID complications.

The new method developed by researchers in China and at the King Abdullah University of Science and Technology, Saudi Arabia, overlays artificial intelligence algorithms on top of standard chest imaging data to reveal otherwise indiscernible visual features indicative of lung dysfunction.

As a result, radiologists can identify and analyse novel sub-visual lung lesions,” said computer scientist and computational biologist Xin Gao. “Analysis of these lesions could then help explain patients’ respiratory symptoms,” allowing for better disease management and treatment, he said.

The method first eliminates any anatomical features not associated with the lung parenchyma; the tissues involved in gas exchange that are the main sites of COVID-19–induced damage. That means removing airways and blood vessels, and then enhancing the pictures of what is left behind to expose lesions that might be missed.

The researchers trained and validated their algorithms using computed tomography (CT) chest scans from thousands of people hospitalised with COVID-19 in China.

Gao and colleagues demonstrated the tool could reveal signs of pulmonary fibrosis in people with Long COVID, thus helping to account for shortness of breath, coughing and other lung problems. He says this diagnosis would be impossible with standard CT image analytics.

Football matches that went ahead during the second COVID-19 wave in Germany were linked to local increases in the number of infections, despite the outdoor setting, reduced stadium occupancy and social distancing, a new study suggests.

The researchers found that local COVID-19 incidence on match days played a key role in subsequent infection levels.

Kai Fischer of the University of Düsseldorf compared counties in Germany where football matches took place with counties without matches between August and November 2020, and then looked at how infection rates evolved over time in these counties.

He found that, on average, just one additional football match in a county led to 0.34 - 0.71 additional cases per 100,000 people three weeks later. This might not sound like much, but when extrapolated to the 7-day incidence per 100,000 people, it is an increase of approximately 3-7% for just one match.

During this period, the authorities restricted the number of people who could attend matches, capping stadium occupancy levels at approximately 20%. Harsher occupancy restrictions were imposed when local weekly case numbers exceeded 35 cases per 100,000 inhabitants. Hygiene and social distancing rules also varied, with top league matches imposing stricter regulations.

Infection levels following a match were strongly linked to the local incidence of COVID-19 on the day of the match. In fact, there were very few infections after matches when the local weekly incidence was under 25 per 100,000 people.

The study used smartphone data to show that large increases in mobility occurred on match days, leading to more human interaction, and proposes that this is a possible underlying mechanism for the phenomenon.

Researchers at the University of Alicante who are studying the global spread of the COVID-19 epidemic have published new data showing the SARS-CoV-2 virus entered the US one month earlier than the official data.

Their analysis, conducted with the University of Pennsylvania, shows that the virus likely entered through California on 28 December 2019. That is 16 days before the officially recognised entry date set by the Centres for Disease Control and Prevention, and 3 days before the first outbreak was reported by authorities in Wuhan, China.

In addition, the study provides evidence that SARS-CoV-2 on average entered each US state a month earlier than previously reflected in official data.

The data were obtained using the Retrospective Methodology to Estimate Daily Infections from Deaths methodology, which the researchers say provides more accurate estimates of the initial cases of COVID-19 in the US and has the capacity to be extrapolated to other countries to retrospectively follow the progress of the pandemic.

Between November 2020 and May 2021, adherence to COVID-19 pandemic restrictions decreased in Italy, with the fastest decreases taking place during times of the most stringent restrictions, according to a new study.

Pandemic fatigue, characterised as lower motivation to adhere to social distancing measures and adopt health protective behaviours, is a significant concern for policymakers and health officials.

From November 2020 to May 2021 in Italy, tiered restrictions were adopted to reduce the spread of COVID-19, with regions declared red, orange, yellow or white depending on the level of infection. Restrictions ranged from a night time curfew in the yellow tier to general stay-at-home mandates in the red tier.

In the new study, the researchers used large scale mobility data from Facebook and Google captured in all 20 Italian provinces to analyse the timing of pandemic fatigue. Facebook reports the change in a user’s number of movements over time, while Google data estimates the change in time spent at home.

People’s relative change in movements increased an average of 0.08% per day and time spent outside the home increased by an average 0.04% per day, leading to a more than 15% increase in relative mobility over the seven-month study period.

During times of red tier restrictions, individual mobility increased an additional 0.16% per day and time spent outside the home increased an additional 0.04% when compared to the average. This means for every 2 week period spent in the red tier, there was an additional average 3% increase in relative mobility.

The authors conclude that changes in adherence to pandemic restrictions are faster during periods characterised by the strictest levels of restrictions. Given that milder tiers have been proven to be effective in mitigating the spread of COVID-19, the researchers suggest policymakers should consider the interplay between the efficacy of restrictions and their sustainability over time.

A new study has shown there has been global collateral damage caused by the disruption to cardiac services during the COVID-19 pandemic, with the researchers warning that problems with heart health will continue to accrue unless mitigation strategies are speedily implemented. 

In the two years from December 2019, when health systems around the world were under extreme pressure and people were fearful of catching COVID-19, individuals experiencing an acute cardiac event such as a heart attack or heart failure either stayed away or could not get admitted to a hospital.  

As a result there was a substantial global decline in hospital admissions of people suffering from cardiovascular disease. 

In cases where people did get medical help there was, on average, more than an hour’s delay in reaching hospital or having contact with paramedics, a huge problem, given that surviving a major heart attack depends on timely and appropriate treatment. 

The study by an international team led by Leeds University, is the first global assessment of the way cardiovascular services coped during the pandemic. 

The researchers analysed data from 189 separate research papers looking at COVID-19's impact on cardiovascular services from 48 countries on six continents and covering a two-year period from December 2019.  

Ramesh Nadarajah, lead author of the paper, said, “Heart disease is the number one killer in most countries – and the analysis shows that during the pandemic people across the world, people did not receive the cardiac care they should have received.” 

The researchers warn that the disruption to cardiovascular services will leave a legacy that requires prompt action by health administrators. “Collateral cardiovascular damage from missed diagnoses and delayed treatments will continue to accrue unless mitigation strategies are speedily implemented. The deferral of interventional procedures, especially for structural heart disease, leaves many patients at high risk of adverse outcomes.” 

Across the world, hospitals saw a 22% decline in people experiencing a serious heart attack, and there was 34% decline in people attending hospital with a less severe form of heart attack. The drop was not due to fewer heart attacks but fewer people attending hospital for treatment.  

Globally, there was a 34% drop in heart operations and just over half (51%) of the electronic implantable devices, such as pacemakers, used to control abnormal heart rhythms were fitted when compared to the non-COVID-19 period. 

While emerging variants of concern have rendered a number of antibodies against SARS-CoV-2 ineffective, new data on AstraZeneca’s Evusheld long-acting antibody combination drug show it retains neutralising activity against the Omicron variants BA.4 and BA.5, according to a new study by Oxford University.

The in vitro data on the new emerging Omicron variants are consistent with Evusheld’s neutralisation activity against previous variants of concern.

The findings are reported on the preprint server bioRxiv, in advance of peer review.

The BA.4 and BA.5, which are now the dominant variants in Africa, appear to be spreading globally in a similar pattern to earlier variants of concern. BA.4 and BA.5 have identical spike protein sequences and appear to have evolved from BA.2.

John Perez, head of late development, Vaccines & Immune Therapies at AstraZeneca, said, “By combining two antibodies with different and complementary activities against SARS-CoV-2, Evusheld was engineered from the start to outsmart the COVID-19 virus and to remain potent in the face of this virus’ ability to rapidly mutate. These findings further support Evusheld as an important option to help protect vulnerable populations such as the immunocompromised who are unable to respond adequately to COVID-19 vaccination and are at high risk for severe disease.”

Approximately 2% of the global population is considered at increased risk of an inadequate response to COVID-19 vaccination and may particularly benefit from treatment with Evusheld in advance of exposure to the virus. This includes people who are immunocompromised, such as cancer patients, transplant patients and anyone taking immunosuppressive drugs.

In what is among the largest studies of Long COVID to date, researchers at the personal genomics testing company 23andMe show it disproportionately affects women.

The study also found that about half of those with persistent symptoms are experiencing them for six months or longer. Even after a year, more than 10% of those who reported being diagnosed with Long COVID continue to have symptoms like brain fog, fatigue, and shortness of breath.

In addition, in analyses controlling for age, sex, and ethnicity, the researchers found that those who reported that they had depression or anxiety prior to COVID-19 infection had a two-fold increase in the risk of being diagnosed with Long COVID, and having a cardiometabolic disease, such as high blood pressure, coronary artery disease, type II diabetes, and high cholesterol, was associated with a 90% higher risk. 

The preliminary data published by 23andme indicates that women are at least twice as likely to be diagnosed with Long COVID compared to men, even when controlling for age, ethnicity, and related health conditions. This contrasts with the overall breakdown of those infected with COVID-19, where men are much more likely to be infected than women. Men are slightly more likely to die from the virus as well.

The 23andMe study data is consistent with other studies that have found women are much more likely to develop Long COVID. More than 78% of those diagnosed with Long COVID in the study were females, compared to about 62% among those who reported not having experienced Long COVID.

Scientists do not understand the causes long COVID, nor how to best treat it. An effort to recruit patients to study the condition by the US National Institutes of Health got off to a slow start, with the agency only recruiting about 1,300 people by late March, far short of the 40,000-patient goal.

The 23andMe study included data from more than 100,000 individuals who reported contracting COVID-19. More than 26,000 said they had experienced Long COVID, and over 7,000 that they had been formally diagnosed with it.

To investigate whether there was an association between long-term exposure to air pollution before the pandemic and COVID-19 severity, researchers have analysed data on all 151,105 people aged 20 years and older with confirmed SARS-CoV-2 infection in 2020 in Ontario.

They modelled historical exposure to three common air pollutants before the pandemic, of fine particulate matter, nitrogen dioxide and ground-level ozone.

The analysis, published in the Canadian Medical Association Journal, adjusted for date of diagnosis, sex and age, being part of an outbreak, essential worker status, neighbourhood socioeconomic status, health care access including previous influenza vaccination history, previous outpatient visits and other factors.

"We observed that people with SARS-CoV-2 infection who lived in areas of Ontario with higher levels of common air pollutants were at elevated risk of being admitted to the ICU after we adjusted for individual and contextual confounding factors, even when the air pollution level was relatively low," said Hong Chen of Health Canada.

They also found an elevated risk of hospitalisation with chronic exposure to particulates and nitrogen dioxide, and an increased risk of death from COVID-19 with chronic exposure to ozone.

The researchers say the results add to the growing reports linking air pollution to COVID-19 severity from other countries, including Spain and Mexico.

More research is needed to understand the mechanisms of how long-term exposure to air pollution may be influencing severity of COVID-19, the researchers say.

A new study by Lude Franke and colleagues at the University of Groningen, Netherlands has found that some people weathered the stress of the COVID-19 pandemic better than others, in part due to their genes.

Over the course of the pandemic, the researchers observed that a genetic predisposition to life satisfaction had an increasing influence on perceived quality of life.

How a person perceives their quality of life depends on a combination of factors that include their genes and their environment. That mix of nature and nurture makes it hard to unpick how genes contribute to feelings about quality of life, but the COVID-19 pandemic allowed Franke and his colleagues to investigate how this stressful, worldwide event interacted with a person's genetics to affect their overall wellbeing.

The team screened the genomes of more than 27,000 participants in the Netherlands who had donated genetic material to a biobank. Then they looked for connections between genetic variants and the participants' responses to a series of questionnaires about lifestyle and mental and physical health given over ten months, starting in March 2020.

The researchers found that some individuals had a genetic tendency towards better wellbeing than others during the pandemic. Additionally, as the pandemic wore on, they found that genetic tendency had an increasingly powerful influence on how those people perceived their quality of life. Moreover, the findings demonstrate that the contribution of genetics to complex traits like wellbeing can change over time.