Corona watch

by | Coronavirus - COVID-19

Short summaries of some highlights of COVID-19 and SARS-CoV-2 research from Australia and around the world.

01 June 2020

The National COVID-19 Clinical Evidence Taskforce has recommended that adults with severe to critical COVID-19 be treated with increased-dose anticoagulants. This follows their consensus guideline that patients with moderate COVID-19 be treated with anticoagulants.

25 May 2020

SARS-CoV-2 may cause injury to placenta

The placentas of 16 women with COVID-19 showed signs of injury indicating abnormal blood flow between the mothers and their babies, in a study published in the American Journal of Clinical Pathology.

Fourteen of the babies were born full term and with normal weights. One was premature and one died in the second trimester.

Compared to controls, the placentas of women with COVID-19 showed increased problems with oxygenation and blood clots. The authors suggest increased antenatal monitoring for women with COVID-19 may be needed.

Low rate of COVID-19 in children tested in Australian emergency department

Children presenting to an Australian emergency department and respiratory infection clinic with symptoms of COVID-19 showed an infection rate of less than one per cent.

Of the 434 children tested at the Royal Children’s Hospital in Melbourne over a 30-day period, only 4 were positive for COVID-19. None were admitted to hospital and all recovered. All had had contact with confirmed cases and 3 of the 4 children had recently travelled overseas.

The authors say their results are consistent with other Australian data showing low rates of confirmed cases in children.

No benefit of hydroxychloroquine in COVID-19

Analysis from the largest observational study to date of hydroxychloroquine or chloroquine in treating COVID-19 could not confirm any benefit of either drug in hospitalised patients.

The data from a multinational registry comprised 96,032 patients in total, who received either chloroquine, chloroquine with an antibiotic, hydroxychloroquine, hydroxychloroquine with an antibiotic, or who were in a control group.

Neither hydroxychloroquine (nor chloroquine), with or without the addition of an antibiotic, improved the outcome of patients, and they were associated with a greater risk of ventricular arrhythmias (abnormal heartbeats) and risk of dying in hospital.

Post script 28 May 2020: An open letter to the Lancet signed by more than 200 doctors has raised concerns regarding the integrity of the data used in this study. The Lancet’s editors have issued a formal Expression of Concern about the study.

Post script 2 June 2020: Similarly, another open letter signed by many doctors has been sent to the New England Journal of Medicine expressing concerns with another study drawing on the same hospital registry data. Editors of the New England Journal of Medicine have also issued an Expression of Concern.

21 May 2020

Acute kidney injury common in COVID-19 hospital patients

Roughly a third of COVID-19 patients admitted to 13 New York hospitals developed acute kidney injury, a study of 5449 patients published in Kidney International has found. Acute kidney injury occurs often among patients with COVID-19 and is associated with a poor prognosis, the authors conclude.

20 May 2020

Potential vaccine produces antibodies to SARS-CoV-2 in human volunteers

A potential vaccine against SARS-CoV-2 has produced antibodies in 8 human volunteers. The messenger RNA vaccine is being developed by US company Moderna.

11 May 2020

Preventive anticoagulants recommended for people with moderate COVID-19

In line with mounting evidence of blood clots, deep vein thrombosis and pulmonary embolism in some people with COVID-19,  Australian clinical guidelines are recommending the use of preventive anticoagulants for adults with moderate COVID disease, where appropriate.

Australia’s National COVID-19 Clinical Evidence Taskforce produces ‘living guidelines’ – high priority evidence-based guidelines updated weekly to bring healthcare professionals real-time advice for treating people with COVID-19. The taskforce is currently reviewing the evidence for higher doses of anticoagulants in adults with severe or critical COVID-19.

6 May 2020

Recovered COVID-19 patients wanted for blood donations to develop treatment

Australian company CSL is seeking Australians who have recovered from COVID-19 to donate blood for a trial of a potential treatment for patients who are seriously ill with COVID-19.

CSL will use plasma from the donors to purify and concentrate antibodies that fight COVID-19. The potential treatment will be known as COVID-19 immunoglobulin.

Donors must be laboratory-confirmed cases of COVID-19 and have recovered for at least 28 days. The donations will be collected by the Australian Red Cross (Lifeblood). Anyone wishing to donate should contact Lifeblood.

4 May 2020

Obesity a risk factor for serious COVID-19 in young people

Obesity is being increasingly recognised as a risk factor for becoming seriously ill with COVID-19 – and it’s not just limited to older people.

Younger people admitted to hospital with COVID-19 were more likely to be obese, according to a letter in the Lancet reporting on 265 patients admitted to 5 different hospitals in the US.

The authors say obesity can restrict ventilation by impeding contraction of the diaphragm, impair immune response to viral infection, causes inflammation in the body (which also impairs the immune response), and adversely affects cardiovascular function.

BCG vaccination being trialled in COVID-19

BCG vaccination has been used for many years to protect against tuberculosis infection. It’s also been shown that BCG vaccination can enhance the innate immune response and reduce severity of some infections by so-called ‘off-target’ effects.

Trials are now underway in Australia and the Netherlands to see if BCG vaccination of healthcare workers reduces the incidence and severity of COVID-19, according to a letter in the Lancet.

N.B. The authors say it’s unlikely that childhood vaccination with BCG given decades ago will help lessen the severity of COVID-19 now, because the effects may be altered by subsequent different vaccinations given after the BCG one.

30 April 2020

Anti-viral drug remdesivir speeds recovery in advanced COVID-19

Hospitalised COVID-19 patients who received the anti-viral drug remdesivir recovered faster than patients receiving placebo (a dummy treatment), preliminary results published by press release from a US trial show.

Remdesivir shortened the time to recovery (defined as discharge from hospital or return to normal activity level) by 31 per cent. Remdesivir cut the recovery time from a median of 15 days to 11 days – a reduction of 4 days.

The drug was given intravenously every day for 10 days.  The study, which was sponsored by the US National Institutes of Health, has not yet been published in a medical journal or on a pre-print server.

COVID-19 patients with digestive symptoms more likely to be hospitalised

Gastrointestinal symptoms such as diarrhoea, lack of appetite and vomiting have been noted in patients hospitalised with COVID-19.

In a pre-print study (that’s one that has not yet been peer reviewed), US researchers have found that having gastrointestinal symptoms is common among patients with COVID-19 and is associated with a greater need to be hospitalised.

Australians working from home are walking less than before

Of the 22 per cent of Australians now working from home during COVID-19, 40 per cent are walking less than they used to, a Heart Foundation survey has found.

The survey of 300 Australians found 40 per cent of those working from home reported walking less, and 34 per cent reported walking more, during COVID lockdowns in April.

As a guide, adults should aim for at least 30 minutes of moderate intensity physical activity (the equivalent of a brisk walk) each day.

29 April 2020

University of Queensland vaccine shows promise in pre-clinical tests

A vaccine developed by the University of Queensland and the Doherty Institute has shown promise in pre-clinical studies.

The vaccine has been able to raise high levels of antibodies that neutralise the SARS-CoV-2 virus in early pre-clinical testing in cell cultures.

“We were particularly pleased that the strength of the antibody response was even better than those observed in samples from COVID-19 recovered patients,” said UQ project co-leader Professor Paul Young.

Strokes in young patients with COVID-19

US experts have reported 5 cases of stroke in patients under 50 years of age who had COVID-19 over a 2-week period. Normally, they would treat an average of 0.73 patients under 50 for large-vessel stroke in a 2-week period. The patients had mild or no symptoms of COVID-19.

23 April 2020

Underlying conditions are common in hospitalised COVID-19 patients

A study of 5700 patients admitted to hospitals in New York with COVID-19 has contributed valuable data on symptoms, co-morbidities (other conditions the patients had) and outcomes of hospitalised patients.

On admission, the most common conditions the patients had, in addition to COVID-19, were high blood pressure (57 per cent), obesity (42 per cent) and diabetes (39 per cent). Thirty per cent of patients had fever when assessed on admission.

At the study end, data was available for 2634 patients who had either been discharged or who had died. Of the 2634 people, 14.2 per cent were treated in intensive care, 12.2 per cent received invasive mechanical ventilation, 3.2 per cent received kidney replacement therapy and 21 per cent died during hospitalisation. Of those who were mechanically ventilated, 88 per cent died.

No patients under 20 years died, and more men than women died in every other age group. Forty per cent of the patients were female.

Richardson S, Hirsch JS, Narasimhan M, et al. Presenting Characteristics, Comorbidities, and Outcomes Among 5700 Patients Hospitalized With COVID-19 in the New York City Area. JAMA. Published online April 22, 2020. doi:10.1001/jama.2020.6775

22 April 2020

SARS-CoV-2: how far does the virus travel in the air?

Just how far do respiratory pathogens travel through the air? More

Hydroxychloroquine treatment results in more deaths in COVID-19 patients than standard care

A study of US veterans hospitalised with COVID-19 has reported a higher death rate in those given hydroxychloroquine (an anti-malarial drug) compared with those receiving standard care.

Results from the treatment of 368 male veterans has been published in a pre-print study (not yet reviewed by other scientists). Patients had received either hydroxychloroquine alone or hydroxychloroquine with the antibiotic azithromycin (in addition to standard supportive care), or standard supportive care alone.

Nearly 28 per cent of the hydroxychloroquine patients died, compared with 11.4 per cent of the patients receiving standard supportive care alone. The addition of azithromycin to hydroxychloroquine resulted in a death rate of 22.1 per cent, but this was not statistically significant.

There was also no evidence that hydroxychloroquine reduced the need for mechanical ventilation, either with or without the addition of azithromycin.

Hydroxychloroquine is known to have potential adverse effects, including changes to the heart rhythm.

Joseph Magagnoli, Siddharth Narendran, Felipe Pereira, Tammy Cummings, James WHardin, S Scott Sutton, Jayakrishna Ambati. Outcomes of hydroxychloroquine usage in United States veterans hospitalized with Covid-19. medRxiv 2020.04.16.20065920; doi:

20 April 2020

Patient-collected swabs a reliable alternative to healthcare worker swabs for coronavirus testing

Patients taking their own swabs for coronavirus testing is a reliable alternative to healthcare workers collecting the swabs, an Australian study has found

In the preprint (not yet peer reviewed) study, 236 patients took their own swabs before also being swabbed by healthcare professionals; 25 were identified as having COVID-19 and 63 had other respiratory viruses. Detection of all viruses (including SARS-CoV-2) by the patient swabs corresponded highly with the swabs taken by the healthcare workers.

The authors conclude that self-collection of nasal and throat swabs for SARS-CoV-2 virus is acceptable and a reliable alternative to samples collected by healthcare workers.

Michael C Wehrhahn, Jennifer Robson, Suzanne Brown, Evan Bursle, Shane Byrne, David New, Smathi Chong, James P Newcombe, Terri Sivertsen, Narelle Hadlow. Self-collection: an appropriate alternative during the SARS-CoV-2 pandemic.medRxiv 2020.04.09.20057901; doi:

Iceland’s COVID-19 testing also suggests many carriers are asymptomatic

A study in Iceland has shed some light on how the SARS-CoV-2 virus spreads in a population. Iceland recorded its first case of COVID-19 at the end of February in a traveller returning from Italy.

Testing has been widespread, including targeted testing of those at high risk (mainly people already symptomatic) and then population-based screening. Population screening was by open invitation to residents who were symptom-free or had mild cold symptoms, backed up by a random sample invitation.

In the population screening of a total of 13,080 people, 100 people tested positive and 43% of those had no symptoms, indicating that many carriers of COVID-19 may not have symptoms or may be positive before they develop symptoms.

Gudbjartsson DF, Helgason A, Jonsson H, et al. Spread of SARS-CoV-2 in the Icelandic Population. N Engl J Med April 14, 2020.

16 April 2020

Viral shedding may begin 2-3 days before first symptoms appear

Viral shedding of patients with COVID-19 may peak on or before they experience symptoms, and a substantial proportion of transmission probably occurs before the first symptoms, a report in Nature Medicine has found.

The authors looked at 414 throat swabs collected from 94 patients and based on their modelling of a separate sample of 77 transmission pairs (index case and secondary case) concluded that 44% of secondary cases were infected before the index case showed symptoms.

They recommend more inclusive criteria for contact tracing to capture potential transmission events 2-3 days before symptoms start.

He, X., Lau, E.H.Y., Wu, P. et al. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nat Med (2020).

Australian researchers developing early warning sewage surveillance for COVID-19

CSIRO researchers have completed a proof-of-concept study where they detected fragments of genetic material from SARS-CoV-2 virus (the causative agent of COVID-19) in untreated sewage from 2 wastewater treatment facilities in Queensland.

The RNA fragments of SARS-CoV-2 would have been shed by people with COVID-19. The researchers say this development will enable surveillance of the spread of the virus through Australian communities.

“The hope is eventually we will be able to not just detect the geographic regions where COVID-19 is present, but the approximate number of people infected – without testing every individual in a location. This will give the public a better sense of how well we are containing this pandemic,” CSIRO Chief Executive, Dr Larry Marshall, said.