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Infectious Diseases

22 September 2020

Coronavirus morning recap: See how Covid infects, repurposed vaccine, and damage to the brain

Recap of the latest coronavirus research, science, and news: Images of how Covid infects the lungs; repurposed measles vaccine trial; and how the brain is affected.

LATEST SCIENCE AND RESEARCH

SEE | Striking images show exactly how Covid-19 virus infects lungs

The lungs are the organs most commonly affected by Covid-19, the disease caused by SARS-CoV-2, and researchers from the UNC School of Medicine have published striking images of cells infected by the virus.

The high-powered microscopic images generated by Dr Camille Ehre from UNC (done in collaboration with two other researchers), show high SARS-CoV-2 viral loads on human respiratory surfaces, ready to spread infection in infected individuals and transmit infection to others.

The images were published in the New England Journal of Medicine.

In a laboratory setting, the researchers inoculated the SARS-CoV-2 virus into human bronchial epithelial cells. Using scanning electron microscopy, they examined the cells 96 hours later.

The images below were re-colourised by UNC medical student Cameron Morrison and indicate the following: the infected ciliated cells with strands of mucus (yellow), attached to cilia tips (blue).

In their published paper, the authors explain that cilia are hair-like structures on the surface of airway epithelial cells that transport mucus (and trapped viruses) from the lungs. The airway epithelium’s job is to moisten and protect the airways.

READ | To what extent is Covid-19 damaging the brain?

Maybe it's a bad trip, or maybe it's the "rona". For one woman – hallucinating about lions and monkeys in her home and convinced her husband was someone else – it turned out to be the latter.

And she's not the only one.

Scientists are struggling to understand Covid-19's effect on the brain as more patients present with neurological symptoms. In the beginning of the pandemic, these symptoms were often missed as healthcare workers were more concerned about keeping patients breathing than noticing whether they were "seeing things".

Scientists have, however, slowly started taking note of neurological disorders in Covid-19 patients. In July, a UK study detailed more than 40 cases of patients presenting with brain dysfunctions like encephalopathy, ischaemic stroke and Guillain-Barré Syndrome, all of which can cause haemorrhaging and inflammation.

These symptoms were even present in patients with mild Covid-19.

Another study also showed how mini-brains grown in a lab proved that viral replication could take place in their cells, signalling potential long-term brain damage, although how the virus would get into the brain remains an unanswered question.

READ | More pets may be getting Covid-19 than realised

There are "substantial" rates of coronavirus infection in dogs and cats whose owners have Covid-19, new research shows.

The researchers also found that, in several cases, infected pets had Covid-like respiratory symptoms at the time their owners were infected.

SARS-CoV-2 has been reported to infect a number of animals, but the risks, susceptibility and symptoms in different species have been unclear.

To learn more, Canadian researchers swabbed the noses, throats and rectums of 17 cats, 18 dogs and one ferret. To determine current infection, the animals were tested within two weeks of a confirmed coronavirus infection or Covid-19 symptoms in their owners.

Blood samples also were taken from eight cats and 10 dogs whose owners were outside the two-week window of infectiousness. This was to determine recent or past infection.

All of the tests for current infection were negative, but coronavirus antibodies were found in the blood of all eight cats, indicating past infection.

CORONAVIRUS CASES LATEST

SA cases update: 

The latest number of confirmed cases is 661 936.

According to the latest update, 15 992 deaths have been recorded in the country.

There have been 591 208 recoveries.

So far, more than 4.04 million tests have been conducted, with 6 180 new tests reported.

Global cases update:

For the latest global data, follow this interactive map from Johns Hopkins University & Medicine.

Early on Tuesday morning, positive cases worldwide were more than 31.16 million, while deaths were more than 962 300.

The United States had the most cases in the world - more than 6.83 million, as well as the most deaths - close to 200 000.

WHAT'S HAPPENING IN SA

READ | Repurposed measles vaccine trials to fight Covid-19 set to kick off in SA - report

An international trial which will test whether a measles, mumps and rubella (MMR) vaccine will protect frontline healthcare workers from Covid-19 is set to kick off in South Africa, according to a report in Business Day on Monday.

The vaccine is popularly used in childhood immunisation programmes, the report said.

The trial is a joint project by the University of the Witwatersrand, Washington University and University College London through the Covid-19 Research Outcomes Worldwide Network for Coronavirus Prevention (Crown Coronation) collaborative.

According to the report, the trial aims to recruit 30 000 healthcare workers from all over the world, including the US, UK, Canada, Ireland, Netherlands, Ghana, Uganda, Zambia, Zimbabwe and South Africa.

The South African Health Products Regulatory Authority is expected to give the go-ahead for the trial soon and 5 000 volunteers will be enrolled in sub-Saharan Africa - half of them will be given the repurposed MMR shot and the other half a placebo.

It is funded by a $9 million grant from a global collaboration backed by the Bill and Melinda Gates Foundation, as well as a R1 million contribution from the South African Medical Research Council, the report said.

WHAT'S HAPPENING IN THE REST OF THE WORLD 

READ | UK faces 'soaring' rise in deaths, Uganda opens borders after 6 months

Reuters reports that Britain will face an exponentially growing death rate from Covid-19 within weeks unless urgent action is taken to halt a rapidly spreading second wave of the outbreak, the country's senior medics said on Monday.

The United Kingdom already has the biggest official Covid-19 death toll in Europe - and the fifth largest in the world - while it is borrowing record amounts in an attempt to pump emergency money through the damaged economy.

But new Covid-19 cases are rising by at least 6,000 per day in Britain, according to week-old data, hospital admissions are doubling every eight days, and the testing system is buckling.

Chris Whitty, the government's chief medical officer, and Patrick Vallance, its chief scientific adviser, cautioned that if left unrestricted the epidemic would reach 50 000 new cases per day by mid October in the United Kingdom.

"If this continued along the path...the number of deaths directly from Covid... will continue to rise, potentially on an exponential curve, that means doubling and doubling and doubling again and you can quickly move from really quite small numbers to really very large numbers," Whitty said.

"If we don't do enough the virus will take off and at the moment that is the path that we are clearly on and if we do not change course then we're going to find ourselves in a very difficult problem."

Latest news:

HEALTH TIPS (as recommended by the NICD and WHO)

• Maintain physical distancing – stay at least one metre away from somebody who is coughing or sneezing

• Practise frequent hand-washing, especially after direct contact with ill people or their environment

• Avoid touching your eyes, nose and mouth, as your hands touch many surfaces and could potentially transfer the virus

• Practise respiratory hygiene – cover your mouth with your bent elbow or tissue when you cough or sneeze. Remember to dispose the tissue immediately after use.

Image credit: Getty Images