domingo, 16 de febrero de 2020

domingo, febrero 16, 2020
The New Coronavirus

New Coronavirus Has Likely Already Spread Globally

The new Covid-19 virus will inevitably spread around the world and there's little anyone can do to stop it, epidemiologists increasingly believe. What's more, far more people have likely been infected with the virus than previously thought. But it's not all bad news.

By Veronika Hackenbroch und Fritz Schaap 

    Health workers check travelers' temperatures at Kotoka International Airport in Accra, Ghana.
Francis Kokoroko/ REUTERS


Two white-clad figures, their faces concealed behind facemasks, wait for a plane full of passengers from Nairobi, Kenya, to disembark at Brazzaville airport in the Republic of Congo. They are both epidemiologists, and while one of them aims a pistol-like thermometer at every person getting off the plane, the other jots down their temperatures with a concerned look on her face. Afterward, they squirt hand sanitizer into each passenger's palms.

The new coronavirus, the World Health Organization (WHO) fears, could spread at any moment from China to Africa. Perhaps it has already arrived and is spreading, since many infected people only show mild symptoms. Maybe it's already making its way through a hospital, a market or an extended family.

"Africa has so many close connections to China, it is hard to imagine that there are no cases in Africa yet," says Peter Piot, the director of the London School of Hygiene and Tropical Medicine, which cooperates closely with scientists in Africa. The fact that no infections have yet been identified there "is really of big concern for me."

On Friday, a first case of the disease was identified in Egypt. But there still have been no cases reported in WHO's Africa region. Egypt is officially part of the Eastern Mediterranean Region.

Many countries in Africa are not sufficiently prepared for SARS-CoV-2, the pathogen that causes the respiratory illness Covid-19, the name given by WHO this week to the condition that has already claimed more than 1,350 lives in China. As of Thursday, there were only 17 laboratories testing samples sent to them from the 47 countries within the WHO's "African region" -- far too few to cover all suspected cases.

"Without diagnostic testing," Piot says, it's impossible to know the extent of the spread of the virus and "the infection may remain hidden for a while. Then you don’t have a chance to intervene early, because you don’t know where the problem actually is."

Many Unreported Cases Worldwide

It is becoming increasingly apparent that the number of confirmed cases reported to the WHO has been seriously understated in some places around the world. Even in Germany, the number of infections could be higher than the official tally of 16.

"It's conceivable that smaller, limited clusters [of infected people] exist that don't register on health officials' radar, even in Germany," says Gérard Krause, a renowned epidemiologist and department head at the Helmholtz Center for Infection Research in Braunschweig, Germany.

    IVDC China CDC HANDOUT/EPA-EFE/REX


Just how incomplete the pool of data is, has been shown in China, where the system for registering new cases is completely overloaded. In the hardest-hit Chinese region of Hubei, authorities changed the way they counted new cases of Covid-19. Instead of only classing cases that have been confirmed by lab results, like they've been doing for the past few weeks, patients with chest infections revealed in CT scans are now also being counted.

This resulted in the number of coronavirus infections jumping by 14,840, while the number of deaths rose by 242. The improved statistics give an idea of the degree to which the epidemic has been underestimated so far.

The official number of cases reported outside China is most likely inaccurate as well. The epidemiologist Moritz Krämer from the University of Oxford, who uses computer simulations to predict the spread of epidemics, is working with colleagues to comb through the websites of public health authorities around the world, making sure to take into account where infected people had traveled prior to being diagnosed.

"One in three infected people had traveled when they were already showing symptoms," Krämer says. "That means thousands of sick people spread the virus around China and the world."

Low Chance of Zero Infections

The fact that Indonesia, for instance, a very densely populated country with close ties to China, has not had a single confirmed case of Covid-19 is all but impossible, according to epidemiologists. The same goes for Thailand, where epidemiologists from the Harvard School of Public Health say that cases have almost certainly been overlooked.

A number of new infections in Singapore have also alarmed experts, according to the Wall Street Journal. Authorities were unable to determine how those affected contracted the disease.

"When something like this happens more often," Krause says, "it shows us that we've been unable to stop the virus' spread."



Singapore of all places, which has been very by-the-book in its efforts to stem the epidemic, could become a hub of sorts for the virus' spread. On Wednesday, 300 employees of the bank DBS had to be evacuated after one of their colleagues was revealed to have contracted Covid-19.

From Wednesday to Thursday, the number of infections in Singapore jumped by 16 percent, according to the local Ministry of Health. By Thursday evening, there were 58 confirmed cases, seven of whom were being treated at intensive care units.

A British businessman brought the new coronavirus with him on a ski vacation in France after picking it up on a work trip to Singapore. From there, he carried it home to Great Britain. He ultimately managed to infect 11 people, including a doctor. Later, a health-care worker in the department of accidents and emergencies at Areal Hospital in West Sussex was also found to have contracted the virus.

"It is concerning that two health-care workers have been infected in the UK," says Tom Frieden, the former head of the U.S. Centers for Disease Control who now heads the global public health organization, "Resolve to Save Lives." A study published in the medical journal Jama a week ago showed that the Covid-19 pathogen -- similar to the SARS and MERS viruses -- can spread in hospitals exceptionally quickly.

The upshot is that epidemiologists increasingly doubt that the spread of the new coronavirus around the world can be prevented.

"At some point, the moment will come when we are forced to give up our containment strategies and focus on mitigation and minimizing the effects of an epidemic, such as through the medical treatment of the seriously ill. If we wait too long, we could wind up with too many resources in the wrong places."

Africa Is Most Vulnerable

How exactly a pandemic would unfold is unclear. It's possible that Covid-19 could turn out to be like any seasonal flu -- with the notable difference that no vaccine exists.

But experts have shared new findings that give cause for hope. Unlike the pathogen of the respiratory disease SARS, Covid-19 pathogens don't only reproduce in the lungs, but also in the back of the throat, like flu viruses.

That's why the new coronaviruses are able to spread more easily than the SARS pathogens, but it's also why they're less deadly, according to Christian Drosten, the director of the Institute of Virology at Berlin's Charite hospital. "For most people, it's probably more like the common cold, and children are seldom affected."

Meanwhile, the fatality rate of the new coronavirus is difficult to determine. Some experts assume a rate of 2 to 3 percent, while others say it's likely less due to the probability of as-of-yet-undiscovered cases -- somewhere closer to 0.2 to 0.3 percent. "We're missing the basics," Frieden says. "It is really important that the WHO team that is now traveling to China looks very closely at all the data."

Krause, the epidemiologist from Braunschweig, wants to study people's natural defenses as part of the largest-ever health study conducted in Germany. "We want to find out whether a part of the population is partially immune to the new pathogen due to previous exposure to other coronaviruses. This could explain why some people have only gotten a little sick."

At the same time, Krause says it's imperative that the population and public health officials begin preparing for the situation to worsen.

"We should not have a false sense of comfort," Frieden says. "I think back to Ebola, when only a couple of cases in the U.S. almost overwhelmed us. This novel virus is very challenging."
A pandemic, however, would be far worse for Africa.

During a meeting at the WHO's headquarters in Brazzaville at the beginning of the week, one thing was clear: Only eight of the 47 countries in the WHO's African region were adequately prepared for a true emergency.

In many other countries, there's a shortage of intensive care units, respirators, medical personnel and even facemasks.

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