COVID-19 spreads even before people show symptoms, study says

Agencies
March 15, 2020

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.

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News Network
June 1,2020

Jun 1: The new coronavirus is losing its potency and has become much less lethal, a senior Italian doctor said on Sunday.

"In reality, the virus clinically no longer exists in Italy," said Alberto Zangrillo, the head of the San Raffaele Hospital in Milan in the northern region of Lombardy, which has borne the brunt of Italy's coronavirus contagion.

"The swabs that were performed over the last 10 days showed a viral load in quantitative terms that was absolutely infinitesimal compared to the ones carried out a month or two months ago," he told RAI television.

Italy has the third-highest death toll in the world from COVID-19, with 33,415 people dying since the outbreak came to light on Feb. 21. It has the sixth-highest global tally of cases at 233,019.

However new infections and fatalities have fallen steadily in May and the country is unwinding some of the most rigid lockdown restrictions introduced anywhere on the continent.

Zangrillo said some experts were too alarmist about the prospect of a second wave of infections and politicians needed to take into account the new reality.

"We've got to get back to being a normal country," he said. "Someone has to take responsibility for terrorizing the country."

The government urged caution, saying it was far too soon to claim victory.

"Pending scientific evidence to support the thesis that the virus has disappeared ... I would invite those who say they are sure of it not to confuse Italians," Sandra Zampa, an undersecretary at the health ministry, said in a statement.

"We should instead invite Italians to maintain the maximum caution, maintain physical distancing, avoid large groups, to frequently wash their hands and to wear masks."

A second doctor from northern Italy told the national ANSA news agency that he was also seeing the coronavirus weaken. "The strength the virus had two months ago is not the same strength it has today," said Matteo Bassetti, head of the infectious diseases clinic at the San Martino hospital in the city of Genoa.

"It is clear that today the COVID-19 disease is different."

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News Network
February 17,2020

Feb 17: Chinese authorities on Monday reported a slight upturn in new virus cases and 105 more deaths for a total of 1,770 since the outbreak began two months ago.

The 2,048 new cases followed three days of declines but was up by just 39 cases from the previous day’s figure. Another 10,844 people have recovered from COVID-19, a disease caused by the new coronavirus, and have been discharged from hospitals, according to Monday’s figures.

The update followed the publication late Saturday in China’s official media of a recent speech by President Xi Jinping in which he indicated for the first time that he had led the response to the outbreak from early in the crisis. While the reports were an apparent attempt to demonstrate the Communist Party leadership acted decisively from the start, it also opened Xi up to criticism over why the public was not alerted sooner.

In his speech, Xi said he gave instructions on fighting the virus on Jan. 7 and ordered the shutdown of the most-affected cities that began on Jan. 23.

The disclosure of his speech indicates top leaders knew about the outbreak’s potential severity at least two weeks before such dangers were made known to the public. It was not until late January that officials said the virus can spread between humans and public alarm began to rise.

New cases in other countries are raising growing concerns about containment of the virus.

Taiwan on Sunday reported its first death from COVID-19, the fifth fatality outside of mainland China. Taiwan’s Central News Agency, citing health minister Chen Shih-chung, said the man who died was in his 60s and had not traveled overseas recently and had no known contact with virus patients.

Japanese Prime Minister Shinzo Abe convened an experts meeting to discuss containment measures in his country, where more than a dozen cases have emerged in the past few days without any obvious link to China.

“The situation surrounding this virus is changing by the minute,” Abe said.

Japanese Health Minister Katsunobu Kato said the country is “entering into a phase that is different from before,” requiring new steps to stop the spread of the virus.

Japan now has 413 confirmed cases, including 355 from a quarantined cruise ship, and one death from the virus. Its total is the highest number of cases among about two dozen countries outside of China where the illness has spread.

Hundreds of Americans from the cruise ship took charter flights home, as Japan announced another 70 infections had been confirmed on the Diamond Princess. Canada, Hong Kong and Italy were planning similar flights.

The 300 or so Americans flying on U.S.-government chartered aircraft back to the U.S. will face another 14-day quarantine at Travis Air Force Base in California and Lackland Air Force Base in Texas. The U.S. Embassy said the departure was offered because people on the ship were at a high risk of exposure to the virus. People with symptoms were banned from the flights.

About 255 Canadians and 330 Hong Kong residents are on board the ship or undergoing treatment in Japanese hospitals. There are also 35 Italians, of which 25 are crew members, including the captain.

In China’s Hubei province, where the outbreak began in December, all vehicle traffic will be banned in another containment measure. It expands a vehicle ban in the provincial capital, Wuhan, where public transportation, trains and planes have been halted for weeks.

Exceptions were being made for vehicles involved in epidemic prevention and transporting daily necessities.

Hubei has built new hospitals with thousands of patient beds and China has sent thousands of military medical personnel to staff the new facilities and help the overburdened health care system.

Last Thursday, Hubei changed how it recognized COVID-19 cases, accepting a doctor’s diagnosis rather than waiting for confirmed laboratory test results, in order to treat patients faster. The tally spiked by more than 15,000 cases under the new method.

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News Network
June 2,2020

Jun 2: Pakistan's COVID-19 cases reached 76,398 on Tuesday after 3,938 new infections were reported across the country, while the death toll due to the coronavirus has gone up to 1,621, according to the health ministry.

The Ministry of National Health Services said that 78 COVID-19 deaths were recorded in the last 24 hours, taking the total number of fatalities in Pakistan to 1,621.

A total of 27, 110 people have recovered, it said.

Sindh has 29,647 patients, Punjab 27,850, Khyber-Pakhtunkhwa 10,485, Balochistan 4,514, Islamabad 2,893, Gilgit-Baltistan 738 and Pakistan-occupied Kashmir 271, it added.

The authorities have conducted 577,974 tests, including 16,548 in the last 24 hours.

The jump in the number of cases comes a day after Prime Minister Imran Khan said that people should learn to live with COVID-19 until a vaccine is developed.

Khan addressed the media after chairing the meeting of National Coordination Committee, the highest body to tackle the pandemic.

"Coronavirus will not go away until the vaccine is discovered. We need to learn to live with it and we can live with it if we follow precautions," he said.

He said the one million volunteers of the government's coronavirus force will raise awareness of the need to follow guidelines.

The government also said that all sectors will be opened slowly after deciding the negative list of businesses which will not be allowed.

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