Indian army's toll double as compared to Pak: Lt Gen Iqbal

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.

Singapore, May 6: Oil prices slipped back Wednesday after two days of gains, although Brent crude remained above $30 a barrel, as renewed US-China tensions offset optimism about the easing of coronavirus lockdowns.

Brent, the international benchmark, fell 1.1 per cent to $30.63 a barrel in early Asian trade. On Tuesday, the contract surged 14 per cent and rose above $30 for the first time since mid-April.

US marker West Texas Intermediate slipped 1.9 per cent and was changing hands for $24.13 a barrel.

Oil markets have been battered as the virus strangled demand due to business closures and travel restrictions, with US crude falling into negative territory last month for the first time.

They started rallying strongly this week as countries from Europe to Asia ease curbs and economies start shuddering back to life.

But gains were capped Wednesday as dealers follow a brewing US-China row after Donald Trump hit out at Beijing over its handling of the outbreak, saying it began in a Wuhan lab, but so far offering no evidence.

"Traders are incredibly cautious this morning, weighing all the possible China responses," said Stephen Innes, chief global market strategist at AxiCorp.

"And the one that would hurt the most would be for China to reduce imports of US oil."

This week's rally was in part driven by a deal agreed between top producers to reduce output by almost 10 million barrels a day, which came into effect on May 1.

There have also been signs that the massive oversupply in the market is starting to ease as demand slowly comes back.

Energy data provider Genscape said earlier this week that stockpiles at the main US oil depot in Cushing, Oklahoma had increased by only 1.8 million barrels last week following weeks of major rises.

The total number of global COVID-19 cases was nearing 9 million, while the deaths have increased to over 467,000, according to the Johns Hopkins University.

By Monday morning, the total number of cases stood at 8,927,195, while the fatalities increased to 467,636, the University's Center for Systems Science and Engineering (CSSE) revealed in its latest update.

With 2,279,306 cases and 119,967 deaths, the US continues with the world's highest number of COVID-19 infections and fatalities, according to the CSSE.

Brazil comes in the second place with 1,083,341 infections and 50,591 deaths.

In terms of cases, Russia ranks third (583,879), and was followed by India (410,461), the UK (305,803), Peru (251,338), Spain (246,272), Chile (242,355), Italy (238,499), Iran (204,952), France (197,008), Germany (191,272), Turkey (187,685), Mexico (180,545), Pakistan (176,617), Saudi Arabia (157,612), Bangladesh (112,306) and Canada (103,078), the CSSE figures showed.

The other countries with over 10,000 deaths are the UK (42,717), Italy (34,634), France (29,643), Spain (28,323), Mexico (21,825) and India (13,254).