Seven months on from when the coronavirus outbreak was officially declared a pandemic, scientists are still unveiling new – and sometimes surprising – findings about how the pathogen might spread.
In the latest research to hit the headlines, scientists in Australia found that virus particles on surfaces could potentially remain infective for four weeks.
Contrasting with earlier findings, suggesting the virus could not remain viable on surfaces for more than a few days, this finding came soon after new guidance highlighted the possible risk of airborne transmission.
And last week, the US Centres for Disease Control said tiny virus-containing particles remaining suspended in the air after being released by infectious people could pass on the pathogen.
The researchers in Australia, who were from the country’s Commonwealth Scientific and Industrial Research Organisation, found the virus could remain viable for 28 days on smooth surfaces such as plastic banknotes and mobile phone screens.
I don't think overall it changes anything. It just re-enforces the, 'Wash your hands,' message
While the work involved samples that were being kept in the dark, when light is known to harm the virus, the scientists said their results could be relevant to efforts to prevent the coronavirus from spreading.
“These findings demonstrate SARS-CoV-2 can remain infectious for significantly longer time periods than generally considered possible,” they wrote.
However, not all experts view laboratory studies of this kind as being helpful in indicating real-world transmission risks. Ian Jones, a professor of virology at the University of Reading in the UK, said data about what “could” happen with the virus was not useful.
"Lab conditions are idealised, in the dark and constant temperature in this case, and it is far more likely temperature would vary, light would vary or wiping would occur," he told The National.
“So I don't think overall it changes anything. It just re-enforces the ‘wash your hands’ message but should not detract from the fact that the majority transmission is by aerosol and that is where the most focus for useful barriers to infection should be.”
Numerous other studies have found that coronavirus samples on surfaces become harmless after much shorter periods of time. One found that it was no longer infectious after three days on plastic or steel, after only 24 hours on cardboard, and after a mere four hours on copper.
The researchers in Australia found the number of infectious virus kept on a surface at 20 degrees Celsius halved every 1.7 to 2.7 days, showing that while some particles could live for 28 days, by that time only a fraction were viable. At 40°C, the number remaining infectious halved every few hours.
The coronavirus is “a pretty tough virus in all sorts of ways”, according to David Taylor, a professor emeritus of pharmaceutical and public health policy at University College London. However, he said surface transmission of the virus was not likely to be the main mode of spread.
“It makes sense to have clean surfaces, but what we don’t know is how much virus that’s on a surface for days … is likely to be a source of infection,” said Prof Taylor.
The Centres for Disease Control’s warning that airborne transmission was possible concerns tiny particles that linger in the air for as long as several hours, as opposed to larger respiratory droplets that a person exhales and that quickly fall to the ground or land on surfaces or other people.
The organisation said most spread of SARS-CoV-2, as the new virus is officially known, were through such larger droplets causing infection “within a short range” of less than 1.8 metres.
Airborne transmission is believed to be uncommon and would normally involve an infectious person producing tiny droplets in an enclosed space for a long time, such as when exercising.
“There is no evidence of efficient spread (i.e., routine, rapid spread) to people far away or who enter a space hours after an infectious person was there,” the CDC guidance states.
Prof Taylor agreed that larger droplets rather than tiny airborne particles were more likely to be involved in the pathogen’s transmission.
“Droplets fall to the ground quicker or they are sprayed on to the lips and nose. That’s the biggest transmission risk, I believe,” he said.
Your Guide to the Home
- Level 1 has a valet service if you choose not to park in the basement level. This level houses all the kitchenware, including covetable brand French Bull, along with a wide array of outdoor furnishings, lamps and lighting solutions, textiles like curtains, towels, cushions and bedding, and plenty of other home accessories.
- Level 2 features curated inspiration zones and solutions for bedrooms, living rooms and dining spaces. This is also where you’d go to customise your sofas and beds, and pick and choose from more than a dozen mattress options.
- Level 3 features The Home’s “man cave” set-up and a display of industrial and rustic furnishings. This level also has a mother’s room, a play area for children with staff to watch over the kids, furniture for nurseries and children’s rooms, and the store’s design studio.
The specS: 2018 Toyota Camry
Price: base / as tested: Dh91,000 / Dh114,000
Engine: 3.5-litre V6
Gearbox: Eight-speed automatic
Power: 298hp @ 6,600rpm
Torque: 356Nm @ 4,700rpm
Fuel economy, combined: 7.0L / 100km
Plan to boost public schools
A major shake-up of government-run schools was rolled out across the country in 2017. Known as the Emirati School Model, it placed more emphasis on maths and science while also adding practical skills to the curriculum.
It was accompanied by the promise of a Dh5 billion investment, over six years, to pay for state-of-the-art infrastructure improvements.
Aspects of the school model will be extended to international private schools, the education minister has previously suggested.
Recent developments have also included the introduction of moral education - which public and private schools both must teach - along with reform of the exams system and tougher teacher licensing requirements.
TWISTERS
Director: Lee Isaac Chung
Starring: Glen Powell, Daisy Edgar-Jones, Anthony Ramos
Rating: 2.5/5
Recipe
Garlicky shrimp in olive oil
Gambas Al Ajillo
Preparation time: 5 to 10 minutes
Cooking time: 5 minutes
Serves 4
Ingredients
180ml extra virgin olive oil; 4 to 5 large cloves of garlic, minced or pureed (or 3 to 4 garlic scapes, roughly chopped); 1 or 2 small hot red chillies, dried (or ¼ teaspoon dried red chilli flakes); 400g raw prawns, deveined, heads removed and tails left intact; a generous splash of sweet chilli vinegar; sea salt flakes for seasoning; a small handful of fresh flat-leaf parsley, roughly chopped
Method
▶ Heat the oil in a terracotta dish or frying pan. Once the oil is sizzling hot, add the garlic and chilli, stirring continuously for about 10 seconds until golden and aromatic.
▶ Add a splash of sweet chilli vinegar and as it vigorously simmers, releasing perfumed aromas, add the prawns and cook, stirring a few times.
▶ Once the prawns turn pink, after 1 or 2 minutes of cooking, remove from the heat and season with sea salt flakes.
▶ Once the prawns are cool enough to eat, scatter with parsley and serve with small forks or toothpicks as the perfect sharing starter. Finish off with crusty bread to soak up all that flavour-infused olive oil.
UK-EU trade at a glance
EU fishing vessels guaranteed access to UK waters for 12 years
Co-operation on security initiatives and procurement of defence products
Youth experience scheme to work, study or volunteer in UK and EU countries
Smoother border management with use of e-gates
Cutting red tape on import and export of food
Who's who in Yemen conflict
Houthis: Iran-backed rebels who occupy Sanaa and run unrecognised government
Yemeni government: Exiled government in Aden led by eight-member Presidential Leadership Council
Southern Transitional Council: Faction in Yemeni government that seeks autonomy for the south
Habrish 'rebels': Tribal-backed forces feuding with STC over control of oil in government territory
Benefits of first-time home buyers' scheme
- Priority access to new homes from participating developers
- Discounts on sales price of off-plan units
- Flexible payment plans from developers
- Mortgages with better interest rates, faster approval times and reduced fees
- DLD registration fee can be paid through banks or credit cards at zero interest rates
At Eternity’s Gate
Director: Julian Schnabel
Starring: Willem Dafoe, Oscar Isaacs, Mads Mikkelsen
Three stars
Film: Raid
Dir: Rajkumar Gupta
Starring: Ajay Devgn, Ileana D'cruz and Saurabh Shukla
Verdict: Three stars
Dust and sand storms compared
Sand storm
- Particle size: Larger, heavier sand grains
- Visibility: Often dramatic with thick "walls" of sand
- Duration: Short-lived, typically localised
- Travel distance: Limited
- Source: Open desert areas with strong winds
Dust storm
- Particle size: Much finer, lightweight particles
- Visibility: Hazy skies but less intense
- Duration: Can linger for days
- Travel distance: Long-range, up to thousands of kilometres
- Source: Can be carried from distant regions
