Nirankari sect head Baba Hardev Singh killed in Canada accident: reports

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.

Melbourne, Apr 10: Scientists have identified six drug candidates from more than 10,000 compounds that may help treat COVID-19.

The research, published in the journal Nature, tested the efficacy of approved drugs, drug candidates in clinical trials and other compounds.

"Currently there are no targeted therapeutics or effective treatment options for COVID-19," said Professor Luke Guddat from the University of Queensland in Australia.

"In order to rapidly discover lead compounds for clinical use, we initiated a programme of high-throughput drug screening, both in laboratories and also using the latest computer software to predict how different drugs bind to the virus," Guddat said.

The project targeted the main COVID-19 virus enzyme, known as the main protease or Mpro, which plays a pivotal role in mediating viral replication, the researchers said.

This makes it an attractive drug target for this virus, and as people don't naturally have this enzyme, compounds that target it are likely to have low toxicity, they said.

"We add the drugs directly to the enzyme or to cell cultures growing the virus and assess how much of each compound is required to stop the enzyme from working or to kill the virus. If the amount is small, then we have a promising compound for further studies," said Guddat.

After assaying thousands of drugs, researchers found of the six that appear to be effective in inhibiting the enzyme, one is of particular interest.

"We're particularly looking at several leads that have been subjected to clinical trials including for the prevention and treatment of various disorders such as cardiovascular diseases, arthritis, stroke, atherosclerosis and cancer," Guddat said.

Researchers said compounds that are already along the pipeline to drug discovery are preferred, as they can be further tested as antivirals at an accelerated rate compared to new drug leads that would have to go through this process from scratch.

"With continued and up-scaled efforts we are optimistic that new candidates can enter the COVID-19 drug discovery pipeline in the near future," Guddat said.

A shrimp seller at the wet market in the Chinese city of Wuhan believed to be the centre of the coronavirus pandemic, may be the first person to have tested positive for the disease, a media report said on Saturday.

The report by the London-based Metro newspaper said that 57-year-old woman, named by the Wall Street Journal as Wei Guixian, was selling shrimp at the Huanan Seafood Market when she developed what she thought was a cold last December.

Chinese digital news outlet, The Paper has said that she may be epatient zero'.

Wei was told by doctors her illness was "ruthless" and other workers at the market had come to the Wuhan Union Hospital with the same symptoms, the Metro newspaper report quoted the outlet as saying.

"Every winter, I suffer from the flu, so I thought it was the flu," the woman was quoted as saying by The Paper news outlet.

The shrimp seller added that she believed she contracted the coronavirus from the shared toilet in the market.

She said the fatal disease would have killed fewer people if the government had acted sooner.

Wuhan Municipal Health Commission has confirmed that Wei was among the first 27 people to test positive for the coronavirus.

It said she was one of 24 cases with direct links to the market, the Metro newspaper reported.

Though Wei may be "patient zero", it does not mean she is the first person to have contracted the virus, added the Metro report.

Chinese researchers have claimed that the first person diagnosed with the airborne virus had no contact with the seafood market and was identified on December 1, 2019.

Wei was later quarantined when a connection was made between the bug and the market before recovering in January.

As of Saturday, the global number of coronavirus cases stood at 104,837 with 27,862 deaths, according to the latest update by the Washington-based Johns Hopkins University.

The US has the highest number of cases at 104,837, followed by Italy 86,498 and China 81,948.

Italy has recorded the highest number of fatalities with 9,134 deaths, followed by Spain and China, at 5,138 and 3,299, respectively.