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 23,2020

Jun 23: US President Donald Trump has issued a proclamation to suspend issuing of H-1B visas, which is popular among Indian IT professionals, along with other foreign work visas for the rest of the year.

Trump said the step was essential to help millions of Americans who have lost their jobs due to the current economic crisis.

Issuing the proclamation ahead of the November presidential elections, Trump has ignored the mounting opposition to the order by various business organisations, lawmakers and human rights bodies.

The proclamation that comes into effect on June 24, is expected to impact a large number of Indian IT professionals and several American and Indian companies who were issued H-1B visas by the US government for the fiscal year 2021 beginning October 1.

They would now have to wait at least till the end of the current year before approaching the US diplomatic missions to get stamping. It would also impact a large number of Indian IT professionals who are seeking renewal of their H-1B visas.

“In the administration of our Nation's immigration system, we must remain mindful of the impact of foreign workers on the United States labour market, particularly in the current extraordinary environment of high domestic unemployment and depressed demand for labour,” said the proclamation issued by Trump.

In his proclamation, Trump said that the overall unemployment rate in the United States nearly quadrupled between February and May of 2020 -- producing some of the most extreme unemployment rates ever recorded by the Bureau of Labor Statistics.

While the May rate of 13.3 percent reflects a marked decline from April, millions of Americans remain out of work.

The proclamation also extends till the end of the year his previous executive order that had banned issuing of new green cards of lawful permanent residency.

Green card holders, once admitted pursuant to immigrant visas, are granted "open-market" employment authorisation documents, allowing them immediate eligibility to compete for almost any job, in any sector of the economy, he said.

“American workers compete against foreign nationals for jobs in every sector of our economy, including against millions of aliens who enter the United States to perform temporary work. Temporary workers are often accompanied by their spouses and children, many of whom also compete against American workers,” Trump said.

“Under ordinary circumstances, properly administered temporary worker programmes can provide benefits to the economy. But under the extraordinary circumstances of the economic contraction resulting from the COVID-19 outbreak, certain non-immigrant visa programmes authorising such employment pose an unusual threat to the employment of American workers,” he said.

For example, Trump said, between February and April of 2020, more than 17 million United States jobs were lost in industries in which employers are seeking to fill worker positions tied to H-2B nonimmigrant visas.

“During this same period, more than 20 million United States workers lost their jobs in key industries where employers are currently requesting H-1B and L workers to fill positions,” he said.

“Also, the May unemployment rate for young Americans, who compete with certain J non-immigrant visa applicants, has been particularly high -- 29.9 percent for 16-19-year-olds, and 23.2 percent for the 20-24-year-old group,” he said.

“The entry of additional workers through the H-1B, H-2B, J, and L non-immigrant visa programmes, therefore, presents a significant threat to employment opportunities for Americans affected by the extraordinary economic disruptions caused by the COVID-19 outbreak,” Trump said.

Trump observed that excess labour supply is particularly harmful to workers at the margin between employment and unemployment -- those who are typically "last in" during an economic expansion and "first out" during an economic contraction.

In recent years, these workers have been disproportionately represented by historically disadvantaged groups, including African Americans and other minorities, those without a college degree, and Americans with disabilities, he said.

The proclamation suspends and limits entry into the US of H-1B, H-2B and L visas and their dependents till December 31, 2020. It also includes certain categories of J visas like an intern, trainee, teacher, camp counselor, or summer work travel programme.

The new rule would apply only to those who are outside the US, do not have a valid non-immigrant visa and an official travel document other than a visa to enter the country.

According to the proclamation, it does not have an impact on lawful permanent residents of the United States and foreign nationals who are spouses or child of an American citizen.

Foreign nationals seeking to enter the US to provide temporary labour or services essential to the food supply chain are also exempted from the latest proclamation.

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News Network
March 25,2020

Hubei, Mar 25: As a bus departed from its terminus at Hankou Railway Station at 5:25 am Wednesday morning, Wuhan started to resume bus service after nine weeks of lockdown.

Apart from a driver, a safety supervisor was also on each bus, whose duty was to make sure all passengers are healthy.
"For those who do not use smartphones, they should bring with them a health certificate issued by the health authorities," said Zhou Jingjing, a safety supervisor aboard bus No. 511 departing from the Wuchang Railway Station complex.
The once hardest-hit city in central China's Hubei Province during the COVID-19 outbreak took unprecedented traffic restrictions on Jan 23. All of its public transport and all outbound flights and trains had been suspended in an attempt to contain the virus within the region.

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News Network
May 20,2020

May 20: The novel coronavirus is behaving differently in patients in northeast China who have contracted it recently compared with early cases, indicating it is changing as it spreads, a prominent doctor said.

China, which has largely brought the virus under control, has found new clusters of infections in the northeastern border provinces of Jilin and Heilongjiang in recent weeks, raising concern about a second wave.

Qiu Haibo, an expert in critical care medicine who is part of a National Health Commission expert group, said the incubation period of the virus in patients in the northeast was longer than that of patients in Wuhan, the central city, where the virus emerged late last year.

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"This causes a problem, as they don't have any symptoms. So when they gather with their families they don't care about this issue and we see family cluster infections," Qiu told state broadcaster CCTV in a programme broadcast late on Tuesday.

Patients in the northeastern clusters were also carrying the virus for longer than earlier cases in Wuhan, and they were taking longer to recover, as defined by a negative nucleic acid test, he said.

Patients in the northeast also rarely exhibited fever and tended to suffer damage to the lungs rather than across multiple organs, he said.

He said the virus found in the northeastern clusters was probably imported from abroad, which could account for the differences.

He did not say where he though they might have come from but both Jilin and Heilongjiang border Russia.

China reported five new coronavirus cases on Wednesday, down from six a day earlier.

Four of the new cases were local transmissions and one was imported by a traveller coming from abroad, the commission said in a statement, compared with three imported cases reported the previous day.

China's total number of coronavirus infections stands at 82,965, while the death toll 4,634. 

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