Note ban anniversary: Amidst chaos and protests PM Modi thanks supporters

New Delhi, Jul 10: With the highest single-day spike of 26,506 COVID-19 cases and 475 deaths reported in the last 24 hours, the total number of COVID-19 cases in India reached 7,93,802 on Friday, according to the Union Ministry of Health and Family Welfare.

Out of the total number of cases, 2,76,685 are active, 4,95,513 have been cured/discharged/migrated and 21,604 have died so far due to the infection.

With as many as 2,30,599 COVID-19 cases, Maharashtra continues to remain the worst-affected state, followed by Tamil Nadu (1,26,581) and Delhi (1,07,051).

Meanwhile, 2,83,659 samples were tested for coronavirus on Thursday, taking the total number of samples tested up to July 9 to 1,10,24,491, according to the Indian Council of Medical Research (ICMR).

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.

Google on Friday announced the launch of a new feature on Google Search, Assistant, and Maps for users in India to help them find information on COVID-19 testing centres near them.

The search giant has partnered with the Indian Council of Medical Research (ICMR) and MyGov to provide the information on authorised testing labs.

The feature is currently available in English and eight Indian languages including Hindi, Telugu, Tamil, Malayalam, Kannada, Bengali, Gujarati, and Marathi.

According to the company, users will now see a new "Testing" tab on the search result page providing a list of nearby testing labs along with key information and guidance needed before using their services.

On Google Maps, when users search for keywords like "COVID testing" or "coronavirus testing" they will see a list of nearby testing labs, with a link to Google Search for the government-mandated requirements.

Google said that the Search, Assistant, and Maps currently feature 700 testing labs across 300 cities and working with authorities to identify and add more testing labs located across the country.

The company reiterates that it is important to follow the recommended guidelines that help determine testing eligibility before visiting.