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.

Washington, Feb 28: US intelligence agencies are monitoring the global spread of coronavirus and the ability of governments to respond, sources familiar with the matter said on Thursday, warning that there were concerns about how India would cope with a widespread outbreak.

While there are only a few known cases in India, one source said the country's available countermeasures and the potential for the virus to spread given India's dense population was a focus of serious concern.

US intelligence agencies are also focusing on Iran, where the country's deputy health minister has fallen ill during a worsening outbreak.

US Secretary of State Mike Pompeo said on Tuesday the United States was "deeply concerned" Tehran may have covered up details about the spread of coronavirus. A US government source said Iran's response was considered ineffective because the government only has minimal capabilities to respond to the outbreak.

Another source said US agencies were also concerned about the weak ability of governments in some developing countries to respond to an outbreak.

The US House of Representatives Intelligence Committee has received a briefing on the virus from the spy agencies. "The Committee has received a briefing from the IC (intelligence community) on coronavirus, and continues to receive updates on the outbreak on a daily basis," an official of the House Intelligence Committee told Reuters.

"Addressing the threat has both national security and economic dimensions, requiring a concerted government-wide effort and the IC is playing an important role in monitoring the spread of the outbreak, and the worldwide response," the official added.

A source familiar with the activities of the Senate Intelligence Committee, led by Republican Senator Richard Burr and Democratic Senator Mark Warner, said the panel was receiving daily updates. The role of US intelligence agencies in responding to the coronavirus epidemic at this point principally involves monitoring the spread of the illness around the world and assessing the responses of governments.

They are working closely with health agencies, such as the US Center for Disease Control, in sharing information they collect and targeting further intelligence gathering.

One source said US agencies would use a wide range of intelligence tools, ranging from undercover informants to electronic eavesdropping tools, to track the virus' impact.