US panel to grill Bezos, Cook, Zuckerberg, Pichai in antitrust hearing

Houston, Mar 15: Researchers, studying the novel coronavirus, have found that the time between cases in a chain of transmission is less than a week, and over 10 per cent of patients are infected by someone who has the virus, but does not show symptoms yet, a finding that may help public health officials contain the pandemic.

The study, published in the journal Emerging Infectious Diseases, estimated what's called the serial interval of the coronavirus by measuring the time it takes for symptoms to appear in two people with the virus -- the person who infects another, and the infected second person.

According to the researchers, including those from the University of Texas at Austin, the average serial interval for the novel coronavirus in China was approximately four days.

They said the speed of an epidemic depends on two things -- how many people each case infects, and how long it takes cases to spread.

The first quantity, the scientists said, is called the reproduction number, and the second is the serial interval.

Due to the short serial interval of the disease caused by the coronavirus -- COVID-19 -- they said, emerging outbreaks will grow quickly, and could be difficult to stop.

“Ebola, with a serial interval of several weeks, is much easier to contain than influenza, with a serial interval of only a few days,” said Lauren Ancel Meyers, study co-author from UT Austin.

Meyers explained that public health responders to Ebola outbreaks have much more time to identify and isolate cases before they infect others.

“The data suggest that this coronavirus may spread like the flu. That means we need to move quickly and aggressively to curb the emerging threat,” Meyers added.

In the study, the scientists examined more than 450 infection case reports from 93 cities in China, and found the strongest evidence yet that people without symptoms must be transmitting the virus -- known as pre-symptomatic transmission.

More than one in ten infections were from people who had the virus but did not yet feel sick, the scientists said.

While researchers across the globe had some uncertainty until now about asymptomatic transmission with the coronavirus, the new evidence could provide guidance to public health officials on how to contain the spread of the disease.

“This provides evidence that extensive control measures including isolation, quarantine, school closures, travel restrictions and cancellation of mass gatherings may be warranted,” Meyers said.

The researchers cautioned that asymptomatic transmission makes containment more difficult.

With hundreds of new cases emerging around the world every day, the scientists said, the data may offer a different picture over time.

They said infection case reports are based on people's memories of where they went and whom they had contact with, and if health officials move quickly to isolate patients, that may also skew the data.

“Our findings are corroborated by instances of silent transmission and rising case counts in hundreds of cities worldwide. This tells us that COVID-19 outbreaks can be elusive and require extreme measures,” Meyers said.

Washington, Jul 9: The United States recorded 55,000 new coronavirus cases in 24 hours on Wednesday (Thursday in Malaysia), a tally by Johns Hopkins University showed, bringing its total to 3,046,351 recorded infections since the pandemic began.

The country, the hardest-hit in the world, had earlier on Wednesday passed the grim milestone of three million infections. The actual number is likely far higher due to issues over getting tested in March and April.

The US also added an additional 833 virus deaths, bringing the death toll to 132,195, the Baltimore-based institution showed at 8.30pm (0030 GMT Thursday).

US President Donald Trump regularly downplays the numbers, attributing them to an increase in testing capacity during the month of June.

Coronavirus cases are surging in several southern hotspots including Texas, Florida, Louisiana and Arizona, but the pandemic has almost entirely receded from its former epicentre in New York and the north-east.

Several states have been forced to suspend their reopening processes or even reverse course, with some ordering bars to close again.

On Wednesday morning, Trump called on schools throughout the country to reopen in the fall, lashing out at his own top health agency to ease health and safety requirements aimed at slowing the spread of the virus, such as social distancing.

Geneva, Jul 2: The World Health Organization (WHO) has estimated the overall number of coronavirus cases globally at 10,357,662, with 508,055 people having died from the disease.

The UN health agency said in the situation report published on late Wednesday that 163,939 new cases had been recorded in the past day, while further 4,188 patients had died.

Americas continue to lead the count with over 5.2 million cases, followed by Europe with more than 2.7 million.

The WHO declared the COVID-19 outbreak a pandemic on March 11.