Stomach bug triggers mass vomiting on Qantas flight

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.

Washington, Feb 19: US President Donald Trump has said he is "saving the big deal" with India for later and he "does not know" if it will be done before the presidential election in November, clearly indicating that a major bilateral trade deal during his visit to Delhi next week might not be on the cards.

"We can have a trade deal with India. But I'm really saving the big deal for later," he told reporters at Joint Base Andrews Tuesday afternoon (local time).

The US and India could sign a "trade package" during the visit, according to media reports.

Asked whether he expects a trade deal with India before the visit, Trump said, "We're doing a very big trade deal with India. We'll have it. I don't know if it'll be done before the election, but we'll have a very big deal with India."

US Trade Representative Robert Lighthizer, the point-person for trade negotiations with India, is likely to not accompany Trump to India, sources said. However, officials have not ruled it out altogether.

In an apparent dissatisfaction over US-India trade ties, Trump said, "We're not treated very well by India." But he praised Prime Minister Narendra Modi and said he is looking forward to his visit to India.

"I happen to like Prime Minister Modi a lot," Trump said.

"He told me we'll have seven million people between the airport and the event. And the stadium, I understand, is sort of semi under construction, but it's going to be the largest stadium in the world. So it's going to be very exciting... I hope you all enjoy it," he told reporters.

Meanwhile, the US-India Strategic and Partnership Forum (USISPF) in a report said the latest quarterly data depict continuation of overall positive bilateral trade trends. The third quarter data reflects some downslide in growth rates.

"It may be due to several reasons, including the unexpected economic slowdown in India's economic growth, impact of US-China trade war, GSP withdrawal from the US side and retaliatory tariffs on specific US goods from the Indian side," USISPF said.

According to the report, the data available for the first three quarters of 2019 (January-September) pulled the overall growth rate in cumulative bilateral trade down to 4.5 percent from 8.4 percent registered for the first two quarters.

Goods and services trade performance in third quarter was dismal at -2.3 percent, in contrast with the impressive 9.6 percent growth witnessed for the first two quarters of the year; while trade in services was up two percent goods trade dropped five percent, the report said.

The cumulative US-India trade in goods and services (USD 110.9 billion) for the first three quarters of 2019 increased 4.5 percent with US exports and imports growing at four percent and five percent respectively.

The US exported USD 45.3 billion worth of goods and services to India in the first three quarters 2019, up 4 percent from the corresponding period in the previous year; and the US imported USD 65.6 billion worth of goods and services from India, up five percent from the previous year's USD 62.5 billion level for the same period, it said.

The USISPF has projected that the total bilateral trade can touch USD 238 billion by 2025 if the current 7.5 percent average annual rate of growth sustains; however, higher growth rates can result in bilateral trade in the range of USD 283 billion and USD 327 billion.

The US remains the top trading partner for India in terms of trade in goods and services, followed by China. While the bilateral trade between US and India is approximately 62 percent in goods and 38 percent in services, the bilateral trade between India and China is dominated by goods.

China had a huge trade surplus of USD 58 billion with India, indicating Beijing's strength in the Indian market, especially in sectors, such as electronics, machinery, organic chemicals, plastics and medical devices.

The US goods exports to India, in comparison, were mainly concentrated in mineral fuels, precious stones, and aircraft. The US faces tough competition with China in the Indian market in areas such as electronics, machinery, organic chemicals and medical devices.

Washington DC, Jul 7: With US President Donald Trump promoting re-opening the economy, the country has now four epicentres of coronavirus instead of one -- Los Angeles, cities in Texas, cities in Florida and Arizona. This has led to the governors fearing that their hospitals could be overrun with patients.

"We are right back where we were at the peak of the epidemic during the New York outbreak...The difference now is that we really had one epicentre of spread when New York was going through its hardship. Now, we really have four major epicentres of spread -- Los Angeles, cities in Texas, cities in Florida and Arizona. Florida looks to be in the worst shape," Scott Gottlieb, former Food and Drug Administration commissioner was quoted by The Washington Post as saying in an interview.

As per the latest data, Florida, New York and California have crossed the 200,000 mark of coronavirus cases.

After Texas continued to break its own record of registering the highest number of coronavirus cases, Austin Mayor Steve Adler (D) was quoted as saying in an interview, "If we do not change this trajectory, then I am within two weeks of having our hospitals overrun."

He further said that intensive care units in the city will start overflowing within 10 days.

Echoing similar sentiments, Judge Lina Hidalgo, the top elected official in Harris County, said, "As long as we're doing as little as possible and hoping for the best, we are always going to be chasing this thing. We are always going to be behind and the virus will always outrun us...And so what we need right now is to do what works, which is a stay-home order."

She was stripped of authority to issue stay-at-home orders after Governor Greg Abbott decided to move forward with the reopening plan.

"It is clear that the (coronavirus) growth is exponential at this point...We have been breaking record after record after record... the last couple of weeks," Miami Mayor Francis Suarez was quoted as saying in an interview.

"The city of Miami was the last city in the entire state of Florida to open. I was criticized for waiting so long. But there is no doubt that the fact that when we reopened, people started socialising as if... the virus didn't exist."

He further said that if the numbers do not begin to fall "more drastic measures" will be taken in the coming week.

As per the latest update by the Johns Hopkins University, a total of 2,938,625 people in the US have tested coronavirus positive and 130,306 deaths have been reported so far.