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

United Nations, May 7: An average of 80,000 COVID-19 cases were reported each day in April to the World Health Organization, the top UN health agency has said, noting that South Asian nations like India and Bangladesh are seeing a spike in the infections while the numbers are declining in regions such as Western Europe.

WHO Director-General Tedros Adhanom Ghebreyesus said on Wednesday that countries must also be able to manage any risk of the disease being imported into their territories, and communities should be fully educated to adjust to what will be a "new norm".

He said as the countries press forward in the common fight against COVID-19, they should also lay the groundwork for resilient health systems globally.

"More than 3.5 million cases of COVID-19 and almost 250,000 deaths have now been reported to the WHO. Since the beginning of April, an average of around 80,000 new cases have been reported to the WHO every day," Ghebreyesus said in Geneva yesterday.

Asserting that the virus cases were not just numbers, he said: "every single case is a mother, a father, a son, a daughter, a brother, sister or friend".

He said while the numbers are declining in Western Europe, more cases are being reported every day from Eastern Europe, Africa, South-East Asia, the Eastern Mediterranean and the Americas. Even within regions and within countries, there are divergent trends, the agency added.

While some countries are reporting an increase in COVID-19 cases over time, many have seen caseloads rise because they have ramped up testing, the WHO official said.

"We've also seen in Europe and Western Europe a fundamental decrease in the number of cases, but we have seen an associated increase in the number of cases reported in places like the Russian Federation. Southeast, the Western Pacific areas are relatively on the downward trend like Korea and others, but then we do see in South Asia, in places like Bangladesh, in India, some trends towards increase.

"So it's very difficult to say that any particular region is improving or (not improving). There are individual countries within each region that are having difficulties getting on top of this disease and I am particularly concerned about those countries that have (an) ongoing humanitarian crisis," WHO's Executive Director Michael Ryan said.

The death toll due to COVID-19 in India rose to 1,783 while the number of cases climbed to 52,952 on Thursday, registering an increase of 89 deaths and 3,561 cases in the last 24 hours, the Union Health Ministry said.

The number of active COVID-19 cases stood at 35,902 while 15,266 people have recovered, it said.

Noting that while seeing an increase in the number of cases is not good in terms of transmission, WHO's Emerging Diseases and Zoonoses Unit head Maria Van Kerkhove said: "but I don't want to equate that with something (being) wrong".

"I want to equate that with countries are working very hard to increase their ability to find the virus, to find people with the virus, to have testing in place to identify who has COVID-19, and putting into place what they need to do to care for those patients," Kerkhove said.

With more countries considering easing restrictions implemented to curb the spread of the coronavirus, the WHO has again reminded the authorities of the need to maintain vigilance.

"The risk of returning to lockdown remains very real if countries do not manage the transition extremely carefully, and in a phased approach," Ghebreyesus said.

He urged countries to consider the UN agency's six criteria for lifting stay-at-home measures.

That advice includes ensuring surveillance is strong, cases are declining and transmission is controlled. Health systems also must be able to detect, isolate, test and treat cases, and to trace all contacts.

Additionally, the risk of outbreak in settings such as health facilities and nursing homes needs to be minimised, while schools, workplaces and other public locations should have preventive measures in place.

"The COVID-19 pandemic will eventually recede, but there can be no going back to business as usual. We cannot continue to rush to fund panic but let preparedness go by the wayside," he said.

He said the crisis has highlighted the importance of strong national health systems as the foundation of global health security: not only against pandemics but also against the multitude of health threats that people across the world face every day.

"If we learn anything from COVID-19, it must be that investing in health now will save lives later," Ghebreyesus said.

While the world currently spends around USD 7.5 trillion on health annually, the WHO believes the best investments are in promoting health and preventing disease.

"Prevention is not only better than cure, it's cheaper, and the smartest thing to do," he said.

The deadly coronavirus, which originated from the Chinese city of Wuhan in December last year, has infected over 3.7 million people and killed 263,831 people globally, according to a tally by Johns Hopkins University.

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Agencies
August 1,2020

Mexico City, Aug 1: The number of people, who have died of COVID-19 in Mexico, has risen by 688 to 46,688 within the past 24 hours, Deputy Health Minister Hugo Lopez-Gatell said.

The number of victims in Mexico is now higher than in the United Kingdom, where 46,119 people have died of the disease. The largest number of fatalities - 153,311 - has been recorded in the United States, while Brazil comes second with 92,475 deaths.

Lopez-Gatell also said on late Friday that the number of confirmed coronavirus cases had increased by 8,458 to 424,637 over the past day.

A day earlier, the Latin American nation recorded 7,730 new cases of the coronavirus, with 639 fatalities.

The World Health Organisation (WHO) declared the COVID-19 outbreak a pandemic on March 11. To date, over 17.5 million people have been infected with the coronavirus worldwide, with over 677,000 fatalities, according to Johns Hopkins University.

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News Network
March 28,2020

Washington, Mar 27: The United States has seen a record 18,000 new confirmed coronavirus cases and 345 deaths over the past 24 hours, according to a Johns Hopkins University tracker.

There are now 97,028 declared virus cases in the country and there have been 1,475 deaths, Johns Hopkins said.

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