Tag: covid transmission

COVID Variants Evolving to Improved Airborne Transmission

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A new study found that people infected with SARS-CoV-2 shed significant numbers of virus particles in their breath – and those infected with the Alpha variant put 43 to 100 times more virus into the air than people infected with the original strains. 

The researchers also found that loose-fitting cloth and surgical masks reduced the amount of virus that gets into the air around infected people by about half. The study was published in Clinical Infectious Diseases.

“Our latest study provides further evidence of the importance of airborne transmission,” said Dr Don Milton, Professor, Environmental Health, University of Maryland School of Public Health. “We know that the Delta variant circulating now is even more contagious than the Alpha variant. Our research indicates that the variants just keep getting better at traveling through the air, so we must provide better ventilation and wear tight-fitting masks, in addition to vaccination, to help stop spread of the virus.”

The numbers of airborne virus particles coming from infections with the Alpha variant (the dominant strain circulating at the time this study was conducted) was much more (18 times more) than could be explained by the increased amounts of virus picked up in nasal swabs and saliva. 
Doctoral student Jianyu Lai, a lead author of the study, explained: “We already knew that virus in saliva and nasal swabs was increased in Alpha variant infections. Virus from the nose and mouth might be transmitted by sprays of large droplets up close to an infected person. But, our study shows that the virus in exhaled aerosols is increasing even more.” These major increases in airborne virus from Alpha infections occurred before the arrival of the Delta variant, suggesting that the virus is evolving to have improved airborne transmission.

To test the efficacy of masks in reducing transmission, the researchers measured how much SARS-CoV-2 is exhaled into the air with and without wearing a cloth or surgical mask. They found that face coverings significantly reduced virus-laden particles in the air around the person with COVID by about 50%.

Co-author Dr Jennifer German said, “The take-home messages from this paper are that the coronavirus can be in your exhaled breath, is getting better at being in your exhaled breath, and using a mask reduces the chance of you breathing it on others.” This means that a layered approach to control measures (including improved ventilation, increased filtration, UV air sanitation, and tight-fitting masks, in addition to vaccination) is critical to protect people in public-facing jobs and indoor spaces.

Source: University of Maryland

COVID Hit South Africa Harder Than Expected Despite Preparedness

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New research finds African countries, assessed as being least vulnerable to an epidemic were the worst affected by COVID, particularly South Africa.

A team of researchers from the NIHR Global Health Research Unit Tackling Infections to Benefit Africa (TIBA) worked with the World Health Organization (WHO) African Region to identify factors affecting mortality rates during Africa’s first two COVID waves and the timing of the first reported cases. The study, published in the journal Nature Medicine, found that countries with greater urban populations and strong international travel links were worst affected by the pandemic. Mortality rates and levels of restrictions, such as lockdowns and travel bans, were found to be lowest in countries previously thought to be at greatest risk from COVID.

Professor Mark Woolhouse, TIBA Director, who co-led the study, said, “Our study shows very clearly that multiple factors influence the extent to which African countries are affected by COVID. These findings challenge our understanding of vulnerability to pandemics.

“Our results show that we should not equate high levels of preparedness and resilience with low vulnerability.

“That seemingly well-prepared, resilient countries have fared worst during the pandemic is not only true in Africa; the result is consistent with a global trend that more developed countries have often been particularly hard hit by COVID.”

Among 44 countries of the WHO African Region with available data, South Africa had the highest mortality rate during the first wave between May and August 2020, at 33.3 deaths recorded per 100k population. Cape Verde and Eswatini had the next highest rates at 17.5 and 8.6 deaths per 100k, respectively. At 0.26 deaths recorded per 100,000, the lowest mortality rate was in Uganda.

South Africa also recorded the highest mortality rate during the second wave between December 2020 and February 2021, at 55.4 deaths per 100,000. Eswatini and Botswana recorded rates of 39.8 and 17.7 deaths per 100,000, respectively. The lowest rate was in Mauritius, which recorded no deaths during the second wave.

“The early models which predicted how COVID would lead to a massive number of cases in Africa were largely the work of institutions not from our continent. This collaboration between researchers in Africa and Europe underlines the importance of anchoring analysis on Africa’s epidemics firmly here,” said Dr. Matshidiso Moeti, WHO Regional Director for Africa and co-author. “We can no longer focus our understanding of disease transmission purely on the characteristics of a virus—COVID operates within a social context which has a major impact on its spread.”

Countries with high rates of HIV were also more likely to have higher mortality rates. This may be because people with HIV often have other health conditions that put them at greater risk from COVID, the team suggests.

The weak association between mortality rate and the timing or severity of government-imposed social restrictions shows the varied impact and enforcement across the region, making a consistent impact pattern difficult to discern. Restrictions during peaks of infection are well documented to have interrupted transmission in the region.

The findings show that the earliest recorded cases of COVID were in countries where most people live in urban areas, with strong international travel links and greater testing capacity. Algeria was the first of 47 African countries to report a case, on 25 February 2020. Most countries had recorded cases by late March 2020, with Lesotho the last to report one, on 14 May 2020.

Higher death rates were observed during the second wave, compared with the first. The infection peak during the second wave was also higher, with 675 deaths across the continent on 18 January 2021 compared with 323 during the first wave peak on 5 August 2020. Potential under-reporting was accounted for in the analysis.

Source: University of Edinburgh

2-Metre Social Distancing May be Insufficient Indoors

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A new study found that the two-metre physical distance required to avoid the viral shedding from a person infected with COVID caused by speaking or breathing may be insufficient indoors.

Researchers from the Penn State Department of Architectural Engineering found that indoor distances of two metres may not be enough to sufficiently prevent transmission of airborne aerosols. Their results were published online in Sustainable Cities and Society.

“We set out to explore the airborne transport of virus-laden particles released from infected people in buildings,” said first author Gen Pei, a doctoral student in architectural engineering at Penn State. “We investigated the effects of building ventilation and physical distancing as control strategies for indoor exposure to airborne viruses.”

The researchers looked at three factors: the amount and rate of air ventilated through a space, the indoor airflow pattern associated with different ventilation strategies and the aerosol emission mode of breathing versus talking. They also compared transport of tracer gas, usually used to test leaks in air-tight systems, and human respiratory aerosols ranging in size from one to 10 micrometres, a size that can still carry SARS-CoV-2.

“Our study results reveal that virus-laden particles from an infected person’s talking — without a mask — can quickly travel to another person’s breathing zone within one minute, even with a distance of two meters,” said corresponding author Donghyun Rim, associate professor of architectural engineering. “This trend is pronounced in rooms without sufficient ventilation. The results suggest that physical distance alone is not enough to prevent human exposure to exhaled aerosols and should be implemented with other control strategies such as masking and adequate ventilation.”

Aerosols were found to travel farther and more quickly in rooms with displacement ventilation, where fresh air continuously flows from the floor and pushes old air to an exhaust vent near the ceiling. This is the type of ventilation system installed in most residential homes, and it can result in a human breathing zone concentration of viral aerosols seven times higher than mixed-mode ventilation systems. Many commercial buildings have mixed-mode systems, which bring in outside air to dilute the indoor air and result in better air integration as well as tempered aerosol concentrations, according to the researchers.

“This is one of the surprising results: Airborne infection probability could be much higher for residential environments than office environments,” Prof Rim said. “However, in residential environments, operating mechanical fans and stand-alone air cleaners can help reduce infection probability.”

According to Rim, increasing the ventilation and air mixing rates can effectively reduce the transmission distance and potential accumulation of exhaled aerosols, but ventilation and distance are only two options in an arsenal of protective techniques.

“Airborne infection control strategies such as physical distancing, ventilation and mask wearing should be considered together for a layered control,” Prof Rim said.

The researchers are now applying this analysis technique to other kinds of occupied spaces, such as classrooms and transportation environments. 

Source: Pennsylvania State University

Ridhwaan Suliman on Twitter: Graphs, Insight and Empathy

Photo by Tracy le Blanc from Pexels
Photo by Tracy le Blanc from Pexels

The Daily Maverick interviewed Dr Ridhwaan Suliman, a senior researcher at CSIR who has entered the spotlight by posting his concise, easy-to-understand COVID numbers graphs on Twitter.

Trained as a mechanical engineer and with a PhD in applied mathematics, he develops computational tools to model and simulate physical systems and processes. Equations in real-world contexts and how they govern physical systems are the relationships he translates into code. And from the code and modelling he can find solutions to make things work more optimally.

As a boy, he took apart his brothers’ old toys to see how they worked, and he took the same approach with COVID data to make sense of it. He started tracking the data in early 2020, and wanted to contribute in some way amidst all the growing uncertainty.

“When I started seeing the raw numbers that were being fed to us daily I couldn’t quite make sense of it myself because the raw numbers in isolation don’t show what’s happening, actually.”

As he tweeted his analyses, he drew attention for his concise summaries of the situation, and praise for helping people to understand the trends. However, he stresses that this is all unpaid, with nobody else’s agenda and that he is not a medical expert.

This week’s update from Dr Ridhwaan

“I’m just comfortable with the numbers.” He gratefully turns to the science experts he engages with on Twitter because “there’s so much more to learn”, he says. That, and a lot of background reading, which he readily dives into.

Dr Suliman’s tracking of the data let him identify gaps and to add to the call for open data, better data collection and smarter analysis. This allows for the factoring in of more variables and laying out of better parameters. “Sure, data can be manipulated to fit a certain narrative, but the benefits outweigh the risks,” he says.

Even in the polarising, easily toxic world of Twitter, Dr Suliman’s interactions show a great empathy.

“We’ve all had numerous moments in this pandemic when things have been depressing and that’s probably something that doesn’t come out on Twitter because you’re generally only sharing things when things are hunky-dory, you don’t share when you’re not okay. There have been many times when I’ve just wanted to stop tweeting, but I get drawn back by people who reach out and say ‘you’re helping me’ – and that’s good enough reason to continue.”

Since he first started on Twitter, he has since appeared numerous times on television to explain the data behind COVID numbers.

Despite his newfound fame however, he looks forward to the time when he can travel again.  “I’ll trade the followers any day for our lives to go back to some sense of normality,” he says.

Source: Daily Maverick

Delta Variant More than Doubles Hospitalisation Risk

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In a study of more than 40 000 COVID cases, those infected with the delta variant have about twice the hospitalisation risk as those infected with the alpha variant. The findings were published in The Lancet Infectious Diseases.

The risk of hospitalisation or emergency hospital care within 14 days of infection with the delta variant was 1.45 times greater than the alpha variant. This is the first study reporting hospitalisation risk for the delta versus alpha variants based on cases confirmed by whole-genome sequencing.

Dr Gavin Dabrera, one of the study’s lead authors and a Consultant Epidemiologist at the National Infection Service, Public Health England, said: “This study confirms previous findings that people infected with Delta are significantly more likely to require hospitalisation than those with Alpha, although most cases included in the analysis were unvaccinated.”

The delta variant emerged in India in December 2020 and early studies found it to be up to 50% more transmissible than the alpha variant, which first appeared in the UK. A preliminary study from Scotland previously reported a doubling of hospitalisation risk with the delta variant over the alpha variant and it is suspected that delta is associated with more severe disease. The previous study used patients’ initial PCR test results and determined which variant they had by testing for a specific gene that is more common in the delta variant.

The researchers analysed healthcare data from 43 338 COVID-positive cases in England between 29 March and 23 May 2021. During the study period, there were 34 656 cases of the alpha variant (80%) and 8682 cases of the delta variant (20%). While the proportion of delta cases in the study period overall was 20%, it eventually encompassed two thirds of new COVID cases in the week starting 17 May 2021 (65%), effectively becoming the dominant strain in England.

Around one in 50 patients were admitted to hospital within 14 days of their first positive COVID test (2.2% alpha cases; 2.3% delta cases. After accounting for factors that are known to affect susceptibility to severe illness from COVID, including age, ethnicity, and vaccination status, the researchers found the risk of being admitted to hospital was more than doubled with the delta variant compared with the alpha variant (2.26-fold increase in risk).

It has been shown in multiple studies that full vaccination prevents both symptomatic infection and hospitalisation, for both alpha and delta variants. Indeed, in this study, only 1.8% of COVID cases (with either variant) had received both doses of the vaccine; 74% of cases were unvaccinated, and 24% were partially vaccinated. With the small number of vaccinated people being hospitalised, it is not possible to statistically compare hospitalisation risk between alpha and delta in such cases, so the results of the study apply to unvaccinated or partially vaccinated cases.

One of the study’s lead authors, Dr Anne Presanis, Senior Statistician at the MRC Biostatistics Unit, University of Cambridge, said: “Our analysis highlights that in the absence of vaccination, any Delta outbreaks will impose a greater burden on healthcare than an Alpha epidemic. Getting fully vaccinated is crucial for reducing an individual’s risk of symptomatic infection with Delta in the first place, and, importantly, of reducing a Delta patient’s risk of severe illness and hospital admission.”

Limitations to the study included some demographic groups possibly being more likely to seek hospital care, which could have biased the results, and there may have been changes in hospital admission policy during the period of the study, although adjustment for demographics and calendar time should have minimised such bias. The authors also did not have access to information about patients’ pre-existing health conditions, which are known to affect the risk of severe illness from COVID. By using age, gender, ethnicity, and estimated level of socioeconomic deprivation, they were able to account for this.

Source: Medical Xpress

Viral Load Alone not Indicative of COVID Transmission Risk

SARS-CoV-2 viruses (yellow) infecting a human cell. Credit: NIH

Viral load as determined by cycle threshold (Ct) has limited utility in guiding decisions regarding isolation and quarantine of COVID patients, according to a study of COVID cases in university students.

Though some in vitro studies indicate that virus load levels in infected individuals affects the successful rate of virus transmission, whether the viral load carried at the individual level can determine transmissibility was unknown. In this study published in The Journal of Molecular Diagnostics, university students underwent regular testing and contact tracing after positive tests, and significant overlap in cycle thresholds (Ct) was found between spreaders and nonspreaders. This brings into question using Ct values to determine transmission rates, with even those with low viral loads able to transmit the virus.
Real-time RT-PCR Ct values represent the number of amplification cycles required for the target gene to exceed a threshold level. Ct values are therefore inversely related to viral load and can provide an indirect method of quantifying the copy number of viral RNA in the sample; however, the use of Ct values as a proxy of viral load is influenced by the assay itself (correlation would stand in the linear dynamic range of the specific RT-PCR assay used) and factors within the sample matrix that can affect amplification efficiency

“We wanted to find whether there was a scientifically sound way to quickly triage students with potential high-risk exposure to COVID positive students for quarantine,” explained co-lead authors Patrice Delafontaine, MD, Department of Medicine, and Xiao-Ming Yin, MD, PhD, Departments of Pathology and Laboratory Medicine, Tulane University School of Medicine. “Some studies have found that the Ct value of the RT-PCR assay is a surrogate for infectivity, and cutoff Ct values have been proposed as a way to guide isolation practices. Through testing and contact tracing, we found that Ct value could not predict transmissibility. We should not overlook positive patients with low viral load, and all positive patients should be quarantined.”

A high-throughput SARS-CoV-2 surveillance testing program was established at Tulane University to support isolation and contact tracing efforts at the campus. Students were tested twice weekly and asked about symptoms they may be experiencing. Contact tracers spoke to all positive case subjects to identify close contacts.
The study looked at 7440 patients who were screened between September 1, 2020 and October 31, 2020, among whom 602 positive cases were identified. From this group, 195 index cases were identified with one or more reported close contacts, who were then tested during their mandated 14-day quarantine period for evidence of transmission from the associated index cases. Of these index cases, 48.2% had at least one contact who became COVID positive, whereas 51.8% of the index cases were nonspreaders with no contacts who subsequently tested positive. Mean Ct values of the spreaders and the nonspreaders were nearly identical.

The researchers then reversed approach, where index cases were traced for 481 students undergoing quarantine due to known exposure to the disease. Eighteen percent of the students became positive during their quarantine. Index cases for the 481 quarantined students were considered spreaders if they were linked to one or more quarantine students with a positive test result, or nonspreaders if they were associated only with students with negative test results. Mean Ct values of the spreader and the nonspreader groups were similar.

The researchers next identified and evaluated 375 positive cases to assess the relationship between symptom presentation and Ct values. Reported symptoms included lethargy, fever, headache, cough, runny nose and gastrointestinal symptoms. Mean and median Ct values were lower in symptomatic cases than in asymptomatic cases, indicating a higher viral load, This suggests that infections with a higher viral load could more often lead to symptom development, or that symptomatic individuals tend to have higher viral loads or maintain their viral loads for a longer period of time. Ct levels may be useful at a population level, in association with symptomatic presentation, to indicate the likelihood of transmission. These values may thus have epidemiologic or surveillance importance.

“Taken together, these index cases suggest that Ct values alone do not predict transmission risk and reporting of Ct values at the individual level, such as by setting a cutoff value of 32, would provide little diagnostic value for case management,” note Dr. Delafontaine and Dr. Yin. “A sensitive and robust SARS-CoV-2 diagnostic testing method is needed to effectively control viral transmission by maximizing the ability to identify and quarantine even those with a low level of virus.”

Source: Elsevier

Many Respiratory Diseases Are Borne by Aerosols

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As the COVID pandemic forced a close study of airborne transmission, new evidence has challenged the idea that many respiratory pathogens besides SARS-CoV-2 were only carried in the large respiratory droplets from coughs and sneezes of infected individuals. Rather, they also spread through virus-laden microscopic respiratory aerosols.

In a review published in Science, Chia Wang and colleagues discussed recent research regarding airborne transmission of respiratory viruses and how an improved understanding of aerosol transmission will enable better-informed controls to reduce and mitigate airborne transmission.

Most respiratory pathogens were until recently assumed to spread largely in large droplets expirated from an infectious person or transferred from contaminated surfaces. Public health recommendations in mitigating viral spread has, thus far, been guided by this understanding.

It is also known however, that a number of respiratory pathogens, such as influenza and the common cold, spread through infectious respiratory aerosols, which can remain suspended in the air, travelling further and for much longer, infecting those that inhale them.

According to a growing body of evidence, much of which gained from studying the spread of COVID, airborne transmission may be a more dominant mode of respiratory virus transmission than previously thought. Here, Wang et al. highlight how infectious aerosols are generated, travel throughout an environment and deliver their viral payloads to hosts. Before COVID, the maximum size for droplets to be classified as aerosols was 5 micrometres, but this has now been updated to 100 micrometres, because up to this size, droplets can remain suspended in the air for up to 5 seconds from a height of 1.5m and travel one metre to be inhaled by another.

The deal with this under-appreciated threat, the authors described ways to mitigate aerosol transmission at long and short ranges, including improvements to ventilation and airflows, air filtration, UV disinfection and personal face mask fit and design.

Source: News-Medical.Net

COVID Most Contagious 2 Days Before to 3 Days After Symptoms Start

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A new study published in JAMA Internal Medicine has found that individuals infected with the virus are most contagious two days before, and three days after, they develop symptoms.

The study also found that infected individuals were more likely to be asymptomatic if they contracted the virus from a primary case (the first infected person in an outbreak) who was also asymptomatic.

“In previous studies, viral load has been used as an indirect measure of transmission,” explained Dr Leonardo Martinez, assistant professor of epidemiology at BUSPH, and who co-led the study with Dr Yang Ge, research assistant in the Department of Epidemiology & Biostatistics at the University of Georgia College of Public Health. “We wanted to see if results from these past studies, which show that COVID cases are most transmissible a few days before and after symptom onset, could be confirmed by looking at secondary cases among close contacts.”

The investigators performed contact tracing and studied COVID transmission among approximately 9000 close contacts of primary cases in the Zhejiang province of China from January 2020 to August 2020. ‘Close’ contacts included household contacts (individuals living in the same household or who dined together), co-workers, people in hospital settings, and riders in shared vehicles. The researchers monitored infected individuals for at least 90 days after their initial positive COVID test results to distinguish between asymptomatic and pre-symptomatic cases.

Of the primary cases, 89 percent developed mild or moderate symptoms, and only 11 percent were asymptomatic — and none developed severe symptoms. Household members of primary cases, as well as those exposed to primary cases more often or for longer time, had the highest infection rates among close contacts. But regardless of these risk factors, close contacts were more likely to contract COVID from the primary infected individual if they were exposed shortly before or after the individual developed noticeable symptoms.

“Our results suggest that the timing of exposure relative to primary-case symptoms is important for transmission, and this understanding provides further evidence that rapid testing and quarantine after someone is feeling sick is a critical step to control the epidemic,” Dr Martinez said.

Compared to mild and moderate symptomatic individuals, asymptomatic primary individuals were much less likely to transmit COVID to close contacts — but if they did, the contacts were also less likely to experience noticeable symptoms.

Source: Newswise

Delta-infected Vaccinated Adults Have Similar Virus Levels to Unvaccinated

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If infected with the Delta variant, virus levels in fully vaccinated adults are as high as unvaccinated people, according to a UK analysis. This adds to evidence indicating that achieving herd immunity is unlikely.

While COVID vaccination has been shown to protect against hospitalisation and death, recent data shows that fully vaccinated people, when infected, carry the same levels of virus as those unvaccinated.

How this affects transmission remains unclear, the researchers have cautioned. “We don’t yet know how much transmission can happen from people who get COVID after being vaccinated – for example, they may have high levels of virus for shorter periods of time,” said Sarah Walker, a professor of medical statistics and epidemiology at the University of Oxford.

“But the fact that they can have high levels of virus suggests that people who aren’t yet vaccinated may not be as protected from the Delta variant as we hoped.”

Recently in the UK, positive tests, hospitalisations and deaths linked to COVID have been rising slowly. In South Africa, the third wave has still not yet abated, with a slight uptick in test positivity rates as noted by Ridhwaan Suliman at the CSIR.

The study, awaiting peer review, found vaccine effectiveness fell against Delta compared to Alpha.

The analysis did not directly investigate whether the lower level of vaccine protection against Delta affected jabs’ ability to prevent severe disease, but low rates of hospitalisation shows it is conferring protection.

The study compared the results of swabs taken from more than 384,500 adults between December 2020 and mid-May 2021, against those from 358,983 adults between mid-May and 1 August 2021 (when Delta became dominant).

The UK findings on peak virus levels after Delta infections in vaccinated people echoed data from a small study cited by the US Centers for Disease Control and Prevention (CDC) last month which prompted the agency to recommend continued mask wearing.

These datasets highlight that vaccinated individuals could still transmit COVID, and testing and self-isolation are still important to cut transmission, said Dr Koen Pouwels, a senior Oxford University researcher. This potential for transmission makes achieving herd immunity even more challenging, he suggested.

It had been hoped the vaccinated would protect the unvaccinated, added Prof Walker. “I suspect that, partly, the higher levels of virus that we’re seeing in these [Delta] infections in vaccinated people are consistent with the fact that unvaccinated people are just going to be at higher risk.”

Compared with AstraZeneca, two doses of the Pfizer vaccine has about 15% greater initial effectiveness against new infections, but its protection declines faster compared with two doses of AstraZeneca. Four to five months after being fully vaccinated, the vaccines’ effectiveness is the same, said Prof Walker.

“Even with these slight declines in protection against all infections and infections with high viral burden, it’s important to note that overall effectiveness is still very high because we were starting at such a high level of protection,” added Dr Pouwels.

Source: The Guardian

One in Ten COVID Cases Infected After Hospital Admission

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In the UK’s first wave, more than one in ten COVID hospitalised patients acquired the disease in a hospital according to researchers conducting the world’s largest study of severe COVID.

Dr Jonathan Read from Lancaster University with colleagues from other UK universities led the research into hospital-acquired infections (HAIs) which was published in The Lancet.

For the study, researchers analysed records of COVID patients in UK hospitals enrolled in the International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) Clinical Characterisation Protocol UK (CCP-UK) study, who became ill before 1st August 2020.

The researchers found that at least 11.1% of COVID patients in 314 UK hospitals were infected after admission. The proportion of hospital-acquired infections also rose to between 16% and 20% in mid-May 2020, well after the first wave’s peak in admissions.

“We estimate between 5699 and 11 862 patients admitted in the first wave were infected during their stay in hospital. This is, unfortunately, likely to be an underestimate, as we did not include patients who may have been infected but discharged before they could be diagnosed,” the researchers said.

“Controlling viruses like SARS-CoV-2 has been difficult in the past, so the situation could have been much worse. However, infection control should remain a priority in hospitals and care facilities,” said Dr Read.

Dr Chris Green, University of Birmingham, said: “There are likely to be a number of reasons why many patients were infected in these care settings. These include the large numbers of patients admitted to hospitals with limited facilities for case isolation, limited access to rapid and reliable diagnostic testing in the early stages of the outbreak, the challenges around access to and best use of PPE, our understanding of when patients are most infectious in their illness, some misclassification of cases due to presentation with atypical symptoms, and an under-appreciation of the role of airborne transmission.”

According to the type of care provided, there were notable differences in infections. Lower proportions of hospital-acquired infection were seen in hospitals providing acute and general care (9.7%) than residential community care hospitals (61.9%) and mental health hospitals (67.5%).
Professor Calum Semple, University of Liverpool, said: “The reasons for the variation between settings that provide the same type of care requires urgent investigation to identify and promote best infection control practice. Research has now been commissioned to find out what was done well and what lessons need to be learned to improve patient safety.”

Source: Lancaster University