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
February 2,2020

Feb 2: The Philippines on Sunday reported the first death from a new virus outside of China, where authorities delayed the opening of schools in the worst-hit province and tightened quarantine measures in a city that allow only one family member to venture out to buy supplies.

The Philippine Department of Health said a 44-year-old Chinese man from Wuhan was admitted on Jan. 25 after experiencing a fever, cough, and sore throat. He developed severe pneumonia, and in his last few days, “the patient was stable and showed signs of improvement, however, the condition of the patient deteriorated within his last 24 hours resulting in his demise.”

The man’s 38-year-old female companion, also from Wuhan, also tested positive for the virus and remains in hospital isolation in Manila.

President Rodrigo Duterte approved a temporary ban on all travelers, except Filipinos, from China and its autonomous regions. The U.S., Japan, Singapore and Australia have imposed similar restrictions despite criticism from China and an assessment from the World Health Organization that they were unnecessarily hurting trade and travel.

The death toll in China climbed by 45 to 304 and the number of cases by 2,590 to 14,380, according to the National Health Commission, well above the number of those infected in in the 2002-03 outbreak of SARS, or severe acute respiratory syndrome, which broke out in southern China and spread worldwide.

Meanwhile, six officials in the city of Huanggang, neighboring the epicenter of Wuhan in Hubei province, have been fired over “poor performance” in handling the outbreak, the official Xinhua News Agency reported.

It cited the mayor as saying the city’s “capabilities to treat the patients remained inadequate and there is a severe shortage in medical supplies such as protective suits and medical masks.”

After Huanggang, the trading center of Wenzhou in coastal Zhejiang province also confined people to homes, allowing only one family member to venture out every other day to buy necessary supplies.

With the outbreak showing little sign of abating, authorities in Hubei and elsewhere have extended the Lunar New Year holiday, due to end this week, well into February. The annual travel crunch of millions of people returning from their hometowns to the cities is thought to pose a major threat of secondary infection at a time when authorities are encouraging people to avoid public gatherings.

All Hubei schools will postpone the opening of the new semester until further notice and students from elsewhere who visited over the holiday will also be excused from classes.

Far away on China’s southeast coast, the manufacturing hub of Wenzhou put off the opening of government offices until Feb. 9, private businesses until Feb. 17 and schools until March 1.

With nearly 10 million people, Wenzhou has reported 241 confirmed cases of the virus, one of the highest levels outside Hubei. Similar measures have been announced in the provinces and cities of Heilongjiang, Shandong, Guizhou, Hebei and Hunan, while the major cities of Shanghai and Beijing were on indefinite leave pending developments.

Despite imposing drastic travel restrictions at home, China has chafed at those imposed by foreign governments, criticizing Washington’s order barring entry to most non-citizens who visited China in the past two weeks. Apart from dinging China’s international reputation, such steps could worsen a domestic economy already growing at its lowest rate in decades.

The crisis is the latest to confront Chinese leader Xi Jinping, who has been beset by months of anti-government protests in the semi-autonomous Chinese city of Hong Kong, the reelection of Taiwan’s pro-independence president and criticism over human rights violations in the traditionally Muslim northwestern territory of Xinjiang. Economically, Xi faces lagging demand and dramatically slower growth at home while the tariff war with the U.S. remains largely unresolved.

Among a growing number of airlines suspending flights to mainland China was Qatar Airways. The Doha-based carrier said on its website that its flights would stop Monday. It blamed “significant operational challenges caused by entry restrictions imposed by a number of countries” for the suspension of flights.

Oman also halted flights to China, as did Saudi Arabia’s flagship national carrier, Saudia.

Saudi Arabia’s state-run TV reported that 10 Saudi students were evacuated from Wuhan on a special flight. It said the students would be screened upon arrival, but did not say whether they would be quarantined for 14 days.

This weekend, South Korea and India flew hundreds of their citizens out of Wuhan. They went into a two-week quarantine.

On Sunday, South Korea reported three more cases for a total of 15. They include an evacuee, a Chinese relative of a man who tested positive and a man who returned from Wuhan. India reported a second case, also in southern Kerala state.

South Korea also barred foreigners who have stayed or traveled to Hubei province within the last 14 days from entering the country.

Indonesia flew back 241 nationals from Wuhan on Sunday and quarantined them on the remote Natuna Islands for two weeks. Several hundred residents protested the move, with one saying, “This is not because we do not have a sense of solidarity with fellow nationals. But because we fear they could infect us with the deadly virus from China.”

A Turkish military transport plane carrying 42 people arrived in Ankara from Wutan Saturday night. The 32 Turkish, six Azerbaijani, three Georgian nationals and an Albanian will remain under observation for 14 days, together with 20 personnel who participated in the evacuation, Health Minister Fahrettin Koca said.

Vietnam counted its seventh case, a Vietnamese-American man who had a two-hour layover in Wuhan on his way from the U.S. to Ho Chi Minh City.

The virus’ rapid spread in two months prompted the WHO on Thursday to declare it a global emergency.

That declaration “flipped the switch” from a cautious attitude to recommending governments prepare for the possibility the virus might spread, said the WHO representative in Beijing, Gauden Galea. Most cases reported so far have been people who visited China or their family members.

WHO said it was especially concerned that some cases abroad involved human-to-human transmission.

“Countries need to get ready for possible importation in order to identify cases as early as possible and in order to be ready for a domestic outbreak control, if that happens,” Galea told The Associated Press.

Both the new virus and SARS are from the coronavirus family, which also includes those that cause the common cold.

The death rate in China is falling, but the number of confirmed cases will keep growing because thousands of specimens from suspected cases have yet to be tested, Galea said.

“The case fatality ratio is settling out at a much lower level than we were reporting three, now four, weeks ago,” he said.

Although scientists expect to see limited transmission of the virus between people with family or other close contact, they are concerned about cases of infection spreading to people who might have less exposure.

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Agencies
August 3,2020

New York, Aug 3: The number of coronavirus cases confirmed all over the world has surpassed 18 million, while the global COVID-19 death toll stands at over 687,000 according to data from the Johns Hopkins University's Coronavirus Resource Center.

As of 06:00 Moscow time on Monday (03:00 GMT), there are 18,017,556 confirmed coronavirus cases in the world. The global death toll from COVID-19 stands at 687,930. The number of recovered individuals stands at 10,649,108.

The United States remains the country with the largest number of cases (4,665,932) and the highest COVID-19 death toll (154,841), according to the latest data from the Johns Hopkins University.

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News Network
January 27,2020

Shanghai, Jan 27: The death toll from a coronavirus outbreak in China rose to 81 on Monday, as the government extended the Lunar New Year holiday and more big businesses shut down or told staff to work from home in an effort to curb the spread.

Chinese Premier Li Keqiang visited the central city of Wuhan, the epicenter of the outbreak, as the government sought to signal it was responding seriously to the crisis.

The total number of confirmed cases in China rose about 30% to 2,744, about half of them in Hubei province, whose capital is Wuhan.

As worries grew around the world, Chinese-ruled Hong Kong, which has had eight confirmed cases, banned entry to people who had visited Hubei in the past 14 days. The ban did not cover Hong Kong residents.

The number of deaths from the flu-like virus in Hubei climbed to 76 from 56, health officials said, with five deaths elsewhere in China, including the southern island province of Hainan, which reported its first fatality on Monday.

While a small number of cases have been confirmed in more than 10 countries, linked to people who traveled from Wuhan, no deaths have been reported elsewhere.

Li is the most senior leader to visit Wuhan since the outbreak began. Clad in a blue protective suit and mask, he inspected efforts to contain the epidemic and spoke to patients and medical staff, the government said.

The government is extending the week-long Lunar New Year holiday by three days to February 2, in a bid to slow the spread of the virus. The Lunar New Year is usually a time for millions of people to travel, but many have had to cancel their plans because of travel curbs over the virus.

Incubation

Wuhan is already in virtual lockdown and severe limits on movement are in place in several other Chinese cities.

The city of 11 million clamped down further on Monday, announcing the suspension of visa and passport services until January 30.

Despite the curbs, the mayor of Wuhan said on Sunday that five million people had left the city for holidays and other reasons.

Images from Wuhan showing hospital corridors packed with people seeking treatment have circulated on social media, along with complaints of soaring prices for essentials such as vegetables.

Chinese leaders have urged transparency in the crisis, after public trust was eroded by the cover-up of the spread of Severe Acute Respiratory Syndrome (SARS), a coronavirus that originated in China and killed nearly 800 people globally in 2002 and 2003.

Much is not known about the newly identified coronavirus, including how easily it spreads and just how dangerous it is. It can cause pneumonia, which has been deadly in some cases.

National Health Commission minister Ma Xiaowei said on Sunday the incubation period could range from one to 14 days, and the virus was infectious during incubation, unlike SARS.

That compares with a World Health Organization (WHO) estimate of two to 10 days for the incubation period.

“Understanding the time when infected patients may transmit the virus to others is critical for control efforts,” the WHO said.

The virus is believed to have originated late last year in a Wuhan market illegally selling wildlife. It has spread to other cities, including Beijing and Shanghai, as well as more than 10 countries including France, Japan and the United States.

‘Overwhelmed’

Australia confirmed its fifth case on Monday involving a woman on the last flight out of Wuhan to Sydney before China’s travel ban.

Health minister Greg Hunt told the Australian Broadcasting Corporation (ABC) authorities aimed to get about 100 Australian children and young people out of Wuhan.

One father of two, Nathan Wang, told the ABC his wife was stuck in Wuhan with the children. “We absolutely want the children to come back, because hospitals in Wuhan are overwhelmed,” he said.

Airports around the world have stepped up screening of passengers from China, although some health experts have questioned its effectiveness.

Last week the WHO stopped short of calling the outbreak a global health emergency, but some health experts question whether China can contain the epidemic.

WHO Director-General Tedros Adhanom Ghebreyesus is due to travel to Beijing to meet officials and health experts.

Australia, France, Italy, Japan and the United States have all said they are working to evacuate citizens from Wuhan.

Some of China’s biggest companies have been affected, with hotpot restaurant chain Haidilao International Holding shutting branches nationwide from Sunday until Friday.

Gaming giant Tencent Holdings Ltd advised staff to work from home until February 7, and e-commerce firm Alibaba removed vendors’ offers of overpriced face masks from its online Taobao marketplace as prices surged.

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