India among London's fastest growing tourism markets: Report

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.

Ottawa, Jun 25: Prime Minister Justin Trudeau took his son out for ice cream on Wednesday in his first family outing since Canada started easing out of its pandemic lockdown.

It was also Saint-Jean-Baptiste Day in Quebec province.

Wearing masks, the Canadian leader and his six-year-old son Hadrien were cheered at Chocolats Favoris in Gatineau, Quebec.

According to a pool report, Trudeau said the shop tapped into a federal emergency wage subsidy and business loan in order to weather the pandemic, and "avoid being frozen out of the frozen treat market."

Hadrien is said to have bounced with excitement, settling on a vanilla cone with a cookie topping while dad bought a vanilla cone dipped in chocolate for himself.

Father and son then headed out to the patio, where they doffed their masks to eat their cones.

Canada's provinces and territories declared states of emergency mid-March, closing schools and non-essential businesses in response to the pandemic.

Jakarta, Mar 15: Indonesia's transport minister is in intensive care after testing positive for the novel coronavirus, an official has said, as schools and tourist attractions were ordered to close over the health threat.

Transportation Minister Budi Karya Sumadi was receiving treatment at an army hospital in Jakarta, State Secretary Pratikno said on Saturday.

A hospital spokesman said Sumadi was encountering difficulty breathing but that his condition was improving.

Pratikno said Sumadi was involved in virus mitigation efforts, particularly the evacuation of Indonesians from epicenters of the outbreak, and that President Joko Widodo had called for tests to be carried out on other ministers.

Cases of the virus in Indonesia, the world's fourth most populous country, have jumped from zero two weeks ago to 96, with five deaths, according to government spokesperson Achmad Yurianto.

He also said the virus has spread outside Greater Jakarta to Bandung in West Java, Solo in Central Java, Manado in North Sulawesi, Pontianak in West Kalimantan, as well as holiday havens Yogyakarta and Bali.

Following the increase, the government on Saturday established a task force on COVID-19 mitigation.

Jakarta's Governor Anies Baswedan announced that schools would close for two weeks starting Monday, and ordered the closure of city-owned tourist attractions, such as Ragunan Zoo and Ancol beach.

He emphasized that Jakarta would not be locked down but urged people "to be responsible" and called for social distancing when possible.

Similarly, the administration of Solo, Central Java, Friday announced that schools and tourist attractions would close after a coronavirus patient died in the region.

The World Health Organization has said it is particularly concerned about high-risk nations with weaker health systems, which who may lack the facilities to identify cases.

A day after declaring the coronavirus outbreak to be pandemic this week, WHO chief Tedros Adhanom Ghebreyesus called Indonesia's president Widodo and both agreed to "scale up cooperation."