Saudi Arabia eyes tourism growth; to begin issuing tourist visas soon

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

A massive fire engulfed a residential tower in UAE's Sharjah last night. The building has been identified as one Abbco Tower in Al Nahda.

According to the latest inputs, Sharjah Civil Defence teams rushed to the spot and evacuated all residents. 

Firefighters managed to douse the blaze after several hours. The building in question is reportedly a 48-storey structure. Officials are yet to reveal the cause of the fire.

All residents of the building were evacuated while seven incurred minor injuries during the evacuation and were treated at local hospitals, reported the United Arab Emirates' local media.

More details are awaited as this is a developing story.

Riyadh, Mar 18: Private-sector businesses in Saudi Arabia on Wednesday were ordered to introduce enforced remote working for all employees for 15 days in an attempt to prevent the spread of the coronavirus.

Businesses that require staff to be physically present to ensure they continue to operate — including those in vital or sensitive sectors such as electricity, water and communications — must reduce the number of workers in their offices to the bare minimum. This can be no more than 40 percent of the total number of staff.

In such cases precautionary measures set by the Ministry of Health must be followed. At offices, and staff accommodation, with more than 50 workers, an area at the entrance must be provided where temperatures can be taken and symptoms checked.

Employers must also set up a mechanism for workers to report any symptoms, such as high temperature, coughing or shortness of breath, or contact they have had with infected individuals or people who recently returned from other countries without following proper Ministry of Health quarantine procedures.

Inside offices, a safe amount of space between employees must be maintained at all times. In addition, all health clubs and nurseries provided by employers must close.

Pregnant women and new mothers, people suffering from respiratory diseases, those with immune-system problems or chronic conditions, cancer patients and employees above the age of 55 are to be given 14 days compulsory paid leave, which will not be deducted from their annual entitlement.

Businesses that are excluded from the new measures include pharmacies and supermarkets, and their suppliers. Private-sector organizations that provide services to government agencies must contact them before suspending workplace attendance. Any other business that considers it impossible to operate with only 40 percent of staff in the workplace must submit an exemption request to the authority that supervises it.