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 9,2020

Washington, Jun 9: When epidemiologists talked about "flattening the curve," they probably didn't mean it this way: the US hit its peak coronavirus caseload in April, but since that time the graph has been on a seemingly unending plateau.

That's unlike several other hard-hit countries which have successfully pushed down their numbers of new cases, including Spain and Italy, which now have bell-shaped curves.

Experts say the prolonged nature of the US epidemic is the result of the cumulative impact of regional outbreaks, as the virus that started out primarily on the coasts and in major cities moves inward.

Layered on top of that are the effects of lifting lockdowns in parts of the country that are experiencing rising cases, as well as a lapse in compliance with social distancing guidelines because of economic hardship, and in some cases a belief that the threat is overstated.

"The US is a large country both in geography and population, and the virus is at very different stages in different parts of the country," Tom Frieden, a former director of the Centers for Disease Control and Prevention told AFP.

The US saw more than 35,000 new cases for several days in April. While that figure has declined, it has still been exceeding 20,000 regularly in recent days.

By contrast, Italy was regularly hitting more than 5,000 cases per day in March but is currently experiencing figures in the low hundreds.

"We did not act quickly and robustly enough to stop the virus spreading initially, and data indicate that it travelled from initial hotspots along major transport routes into other urban and rural areas," added Frieden, now CEO of the non-profit Resolve to Save Lives.

To wit: the East Coast states of New York, New Jersey and Massachusetts accounted for about 50 percent of all cases until about a month or so ago -- but now the geographic footprint of the US epidemic has shifted to the Midwest and southeast, including Florida.

Another key problem, said Jennifer Nuzzo, an epidemiologist at Johns Hopkins, is that the United States is still not doing enough testing, contact tracing and isolation.

After coming late to the testing party -- for reasons ranging from technical issues to regulatory hurdles -- the US has now conducted more COVID-19 tests than any other country.

It even has one of the highest per capita rates per country of 62 per 1,000 people, according to the website ourworldindata.org -- better than Germany (52 per 1,000) and South Korea (20 per 1,000).

But according to Nuzzo, these numbers are misleading, because "the amount of testing that a country should do should be scaled to the size of its epidemic.

"The United States has the largest epidemic in the world so obviously we need to do a lot more testing than any other country."

For Johns Hopkins, the more important metric is the positivity rate -- that is, out of all tests conducted, how many came back positive for COVID-19.

As of June 7, the United States had an average daily positivity rate of 14 percent, well above the World Health Organization guideline of 5 percent over two weeks before social distancing guidelines should be relaxed.

By contrast, Germany, which has tested far fewer people in relation to its population, has a positivity rate of 5 percent.

Even if testing were scaled up, carrying out tests in of itself does very little good without the next steps -- finding out who was exposed and then asking them to isolate.

Here also, too many US states are lagging woefully behind.

Texas, which is experiencing a surge in cases after relaxing its lockdown, is a case in point. The state targeted hiring a modest 4,000 tracers by June, but according to local reports is still more than a thousand shy of even that goal.

Opt-in app based efforts have also been slow to get off the ground.

Then there is the fact that some people are growing tired of lockdowns, while others don't have the economic luxury of being able to stay home for prolonged periods.

The government sent some 160 million Americans a single stimulus check of up to $1,200 back in April but it's not clear whether more will be forthcoming.

Still others, particularly in so-called red states under Republican leadership, have chafed under restrictions and mask-wearing guidelines that they see as an affront to their personal freedom.

"The US is kind of on the extreme of the individual liberty side," Sten Vermund, dean of the Yale School of Public Health, told AFP.

Part of this has to do with mixed messaging from Republican leaders, including President Donald Trump, said Nuzzo.

"We have had at the highest political level an assertion that this is a situation that's been overblown, and that maybe certain protective behaviors are not necessary," she said.

More recently, tens of thousands of people across the country have taken to the streets to protest the killing on an unarmed black man by police, risking coronavirus infection to demonstrate against the public health threat of racialized state violence.

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Agencies
March 1,2020

Washington, Mar 1: Beginning April 1, Indians wishing to immigrate to America will now have to pay an additional $50,000 for the EB-5 or the US investor visa, a media report said.

Although, this additional tax would impact all visa categories, it will predominantly create a barrier for people investing in the EB-5 visa programme, the American Bazaar daily said in the report on Friday.

In 2019, the EB-5 investor visa programme, for the first time since the 1990's, increased the minimum investment amount to $900,000.

With this increase in minimum investment, the new 5 per cent additional tax would mean that applicants would have to pay the extra $50,000, when they move money to an escrow account in the US to fulfil their application criterion.

"The changes to the tax on remittances is a reminder to Indians to carefully plan their tax position before making the move to the US," the American Bazaar quoted Mark Davies, Global Chairman, Davies & Associates LLC, as saying.

"People seeking to emigrate who do not wish to pay this tax at source and rather account for it later may wish to move their money ahead of the new rules coming into effect.

"It is possible to pre-emptively move money into an escrow account in the US until such a time as they are ready to proceed with emigration process," he added.

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News Network
June 4,2020

Beijing, Jun 4: Around 40 students and staff members of a primary school in China were stabbed by a security guard, official media reported today.

The incident happened at a school in China's Guangxi province, state-run China Daily said in a brief report.

Further details about the attack are awaited.

Knife attacks by disgruntled people have been taking place in different parts of China in the past few years, reported news agency Press Trust of India.

The attackers targeted mainly kindergarten and primary schools besides public transport, the news agency reported.

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