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
January 31,2020

Wuhan, Jan 31: The World Health Organization declared a global emergency over the new coronavirus, as China reported Friday the death toll had climbed to 213 with nearly 10,000 infections.

The UN health agency based in Geneva had initially downplayed the threat posed by the disease, but revised its risk assessment after crisis talks.

suspended or reduced service to China include British Airways, German flag carrier Lufthansa, American Airlines, KLM and United.

Chinese efforts to halt the virus have included the suspension of classes nationwide and an extension of the Lunar New Year holiday.

All football matches across the country also will be postponed, the Chinese Football Association said on Thursday, including games in the top-tier Chinese Super League.

World stock markets tumbled again Thursday on fears that trouble in the "world's factory" would upset global supply chains and dent profits.

Toyota, IKEA, Starbucks, Tesla, McDonald's and tech giant Foxconn were among the corporate giants temporarily freezing production or closing large numbers of outlets in China.

Volkswagen announced Thursday its China joint-venture plants would not start production again before February 9.

US Federal Reserve Chairman Jerome Powell said the coronavirus posed a fresh risk to the world economy.

Throughout China, signs of paranoia multiplied, with residents of some Beijing residential compounds erecting makeshift barriers to their premises.

In one of many similar photos posted online, a man wearing a surgical mask and brandishing a traditional martial arts weapon squatted on a barricade outside a Chinese village, near a sign saying: "Outsiders forbidden from entering".

The crisis has caused food prices to spike, and the central government on Thursday blamed this partly on overzealous preventive measures, issuing a directive banning any roadblocks or other hindrances to food shipments.

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News Network
June 22,2020

Karachi, Jun 22: India-born renowned Pakistani Shia scholar and author Talib Jauhari passed away here after a prolonged illness. He was 80.

Jauhari, who was born on August 27, 1939 in Patna, is survived by his three sons, Dawn News reported on Monday.

He migrated to Pakistan along with his father in 1949, two years after the Partition.

After obtaining early education from his father, he went to Iraq where he studied religion for 10 years under the renowned Shia scholars of that time.

Jauhari, who was on a ventilator in the intensive care unit of a private hospital for the past 15 days, breathed his last on Sunday night.

His son Riaz Jauhari confirmed his death and said that the body has been shifted to Ancholi Imambargah for the funeral prayers, The Express Tribune newspaper quoted his son as saying.

Jauhari was respected among his sect as he was a class fellow of the widely revered scholar Ayatollah Sayyid Ali al-Husayni al-Sistani.

He was also a poet, historian and philosopher and authored many books.

Pakistan Prime Minister Imran Khan has condoled Jauhari's death.

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Agencies
August 7,2020

Russia boasts that it's about to become the first country to approve a Covid-19 vaccine, with mass vaccinations planned as early as October using shots that are yet to complete clinical trials -- and scientists worldwide are sounding the alarm that the headlong rush could backfire.

Moscow sees a Sputnik-like propaganda victory, recalling the Soviet Union's launch of the world's first satellite in 1957.

But the experimental Covid-19 shots began first-in-human testing on a few dozen people less than two months ago, and there's no published scientific evidence yet backing Russia's late entry to the global vaccine race, much less explaining why it should be considered a front-runner.

“I'm worried that Russia is cutting corners so that the vaccine that will come out may be not just ineffective, but also unsafe,” said Lawrence Gostin, a global public health law expert at Georgetown University. “It doesn't work that way... Trials come first. That's really important.”

According to Kirill Dmitriev, head of Russia's Direct Investment Fund that bankrolled the effort, a vaccine developed by the Gamaleya research institute in Moscow may be approved in days, before scientists complete what's called a Phase 3 study.

That final-stage study, usually involving tens of thousands of people, is the only way to prove if an experimental vaccine is safe and really works.

Health Minister Mikhail Murashko said members of “risk groups,” such as medical workers, may be offered the vaccine this month.

He didn't clarify whether they would be part of the Phase 3 study that is said to be completed after the vaccine receives “conditional approval.”

Deputy Prime Minister Tatyana Golikova promised to start “industrial production” in September, and Murashko said mass vaccination may begin as early as October.

Dr Anthony Fauci, the top US infectious disease specialist, questioned the fast-track approach last week.

“I do hope that the Chinese and the Russians are actually testing a vaccine before they are administering the vaccine to anyone, because claims of having a vaccine ready to distribute before you do testing I think is problematic at best," he said.

Questions about this vaccine candidate come after the US, Britain and Canada last month accused Russia of using hackers to steal vaccine research from Western labs.

Delivering a vaccine first is a matter of national prestige for the Kremlin as it tries to assert the image of Russia as a global power capable of competing with the US and China.

The notion of being “the first in the world” dominated state news coverage of the effort, with government officials praising reports of the first-step testing.

In April, President Vladimir Putin ordered state officials to shorten the time of clinical trials for a variety of drugs, including potential coronavirus vaccines.

According to Russia's Association of Clinical Trials Organizations, the order set “an unattainable bar” for scientists who, as a result, "joined in on the mad race, hoping to please those at power.”

The association first raised concern in late May, when professor Alexander Gintsburg, head of the Gamaleya institute, said he and other researchers tried the vaccine on themselves.

The move was a “crude violation of the very foundations of clinical research, Russian law and universally accepted international regulations" the group said in an open letter to the government, urging scientists and health officials to adhere to clinical research standards.

But a month later, the Health Ministry authorized clinical trials of the Gamaleya product, with what appeared to be another ethical issue.

Human studies started June 17 among 76 volunteers. Half were injected with a vaccine in liquid form and the other half with a vaccine that came as soluble powder.

Some in the first half were recruited from the military, which raised concerns that servicemen may have been pressured to participate.

Some experts said their desire to perform well would affect the findings. “It's no coincidence media reports we see about the trials among the military said no one had any side effects, while the (other group) reported some," said Vasily Vlassov, a public health expert with Moscow's Higher School of Economics.

As the trials were declared completed and looming regulatory approval was announced last week, questions arose about the vaccine's safety and effectiveness.

Government assurances the drug produced the desired immune response and caused no significant side effects were hardly convincing without published scientific data describing the findings.

The World Health Organization said all vaccine candidates should go through full stages of testing before being rolled out.

“There are established practices and there are guidelines out,” WHO spokesman Christian Lindmeier said Tuesday.

“Between finding or having a clue of maybe having a vaccine that works, and having gone through all the stages, is a big difference.”

Offering an unsafe compound to medical workers on the front lines of the outbreak could make things worse, Georgetown's Gostin said, adding: “What if the vaccine started killing them or making them very ill?”

Vaccines that are not properly tested can cause harm in many ways — from a negative impact on health to creating a false sense of security or undermining trust in vaccinations, said Thomas Bollyky, director of the global health program at the Council on Foreign Relations. 

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