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
May 7,2020

Islamabad, May 7: Pakistan's COVID-19 cases have crossed 24,000 after 1,523 new infections were detected, while the death toll has jumped to 564 with 38 more people succumbing to the coronavirus, health officials said on Thursday.

Even as the country is seeing an increase in the number of coronavirus cases and fatalities, Prime Minister Imran Khan will discuss the easing of lockdown restrictions with his top aides on Thursday.

The Ministry of National Health Services said that out of the 24,073 total cases, Punjab reported 9,077, Sindh 8,640, Khyber-Pakhtunkhwa 3,712, Balochistan 1,495, Islamabad 521, Gilgit-Baltistan 388 and Pakistan-occupied Kashmir 76 cases.

After 38 more deaths on Wednesday, the total coronavirus patient death toll jumped to 564. Another 6,464 have recovered. A total of 1,523 new patients were added in a single day, the ministry.

So far, 244,778 tests have been conducted, including 12,196 in the last 24 hours, it said.

Prime Minister Khan will chair the National Coordination Committee (NCC) meeting on easing the lockdown restrictions in the country. The meeting will be attended by all chief ministers.

The issue was debated in the National Command and Operation Centre (NCOC) on Wednesday and in the Cabinet on Tuesday.

Planning Minister Asad Umar said that different proposals to allow certain businesses to open were prepared and will be presented before the Prime Minister for a final decision.

Earlier, Khan, undeterred by the mounting number of deaths and the new cases, announced that he was against a lockdown as it hits the poor people badly.

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News Network
May 5,2020

May 5: Global coronavirus deaths reached 250,000 on Monday after recorded infections topped 3.5 million, a news agency tally of official government data showed, although the rate of fatalities has slowed.

North America and European countries accounted for most of the new deaths and cases reported in recent days, but numbers were rising from smaller bases in Latin America, Africa and Russia.

Globally, there were 3,062 new deaths and 61,923 new cases over the past 24 hours, taking total cases to 3.58 million.

That easily exceeds the estimated 140,000 deaths worldwide in 2018 caused by measles, and compares with around 3 million to 5 million cases of severe illness caused annually by seasonal influenza, according to the World Health Organization (WHO).

While the current trajectory of COVID-19 falls far short of the 1918 Spanish flu, which infected an estimated 500 million people, killing at least 10% of patients, experts worry the available data is underplaying the true impact of the pandemic.

The concerns come as several countries begin to ease strict lockdowns that have been credited with helping contain the spread of the virus.

"We could easily have a second or a third wave because a lot of places aren't immune," Peter Collignon, an infectious diseases physician and microbiologist at Canberra Hospital, told Reuters. He noted the world was well short of herd immunity, which requires around 60% of the population to have recovered from the disease.

The first death linked to COVID-19 was reported on Jan. 10 in Wuhan, China after the coronavirus first emerged there in December. Global fatalities grew at a rate of 1-2% in recent days, down from 14% on March 21, according to the Reuters data.

DEATH RATE ANOMALIES

Mortality rates from recorded infections vary greatly from country to country.

Collignon said any country with a mortality rate of more than 2% almost certainly had underreported case numbers. Health experts fear those ratios could worsen in regions and countries less prepared to deal with the health crisis.

"If your mortality rate is higher than 2%, you've missed a lot of cases," he said, noting that countries overwhelmed by the outbreak were less likely to conduct testing in the community and record deaths outside of hospitals.

In the United States, around half the country's state governors partially reopened their economies over the weekend, while others, including New York Governor Andrew Cuomo, declared the move was premature.

In Britain, Prime Minister Boris Johnson, who battled COVID-19 last month, has said the country was over the peak but it was still too early to relax lockdown measures.

Even in countries where the suppression of the disease has been considered successful, such as Australia and New Zealand which have recorded low daily rates of new infections for weeks, officials have been cautious.

Australian Prime Minister Scott Morrison has predicated a full lifting of curbs on widespread public adoption of a mobile phone tracking app and increased testing levels.

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News Network
June 13,2020

Shanghai, Jun 13: Authorities in Beijing have temporarily shut a major wholesale agricultural market following a rise in locally transmitted novel coronavirus infections in China's capital city over the past two days.

The closure of the Xinfadi wholesale market at 3 a.m. local time on Saturday (1900 GMT on Friday), came after two men working at a meat research centre who had recently visited the market were reported on Friday as having been infected by the novel coronavirus. It was not immediately clear how the men had been infected.

Concern is growing of a second wave of the new virus, even in many countries that seemed to have curbed its spread. It was first reported at a seafood market in Wuhan, the capital of central China's Hubei province, in December.

Beijing authorities had earlier halted beef and mutton trading at the Xinfadi market, alongside closures at other wholesale markets around the city.

Reflecting concerns over the risk of further spread of the virus, major supermarkets in Beijing removed salmon from their shelves overnight after the virus causing COVID-19 was discovered on chopping boards used for imported salmon at the market, the state-owned Beijing Youth Daily reported.

Beijing authorities said more than 10,000 people at the market will take nucleic acid tests to detect coronavirus infections. The city government also said it had dropped plans to reopen schools on Monday for students in grades one through three because of the new cases.

Health authorities visited the home of a Reuters reporter in Beijing's Dongcheng district on Saturday to ask whether she had visited the Xinfadi market, which is 15 km (9 miles) away. They said the visit was part of patrols Dongcheng was conducting.

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China reported 11 new COVID-19 cases and seven asymptomatic cases for Friday, the national health authority said on Saturday. And all six locally transmitted cases were confirmed in Beijing.

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