Recovery from coronavirus may not confer immunity, warn experts

News Network
April 17, 2020

Paris, Apr 17: Even as virologists zero in on the virus that causes COVID-19, a very basic question remains unanswered: do those who recover from the disease have immunity?

There is no clear answer to this question, experts say, even if many have assumed that contracting the potentially deadly disease confers immunity, at least for a while.

"Being immunised means that you have developed an immune response against a virus such that you can repulse it," explained Eric Vivier, a professor of immunology in the public hospital system in Marseilles.

"Our immune systems remember, which normally prevents you from being infected by the same virus later on."

For some viral diseases such a measles, overcoming the sickness confers immunity for life.

But for RNA-based viruses such as Sars-Cov-2 -- the scientific name for the bug that causes the COVID-19 disease -- it takes about three weeks to build up a sufficient quantity of antibodies, and even then they may provide protection for only a few months, Vivier told AFP.

At least that is the theory. In reality, the new coronavirus has thrown up one surprise after another, to the point where virologists and epidemiologists are sure of very little.

"We do not have the answers to that -- it's an unknown," Michael Ryan, executive director of the World Health Organization's Emergencies Programme said in a press conference this week when asked how long a recovered COVID-19 patient would have immunity.

"We would expect that to be a reasonable period of protection, but it is very difficult to say with a new virus -- we can only extrapolate from other coronaviruses, and even that data is quite limited."

For SARS, which killed about 800 people across the world in 2002 and 2003, recovered patients remained protected "for about three years, on average," Francois Balloux director of the Genetics Institute at University College London, said.

"One can certainly get reinfected, but after how much time? We'll only know retroactively."

A recent study from China that has not gone through peer review reported on rhesus monkeys that recovered from Sars-Cov-2 and did not get reinfected when exposed once again to the virus.

"But that doesn't really reveal anything," said Pasteur Institute researcher Frederic Tangy, noting that the experiment unfolded over only a month.

Indeed,several cases from South Korea -- one of the first countries hit by the new coronavirus -- found that patients who recovered from COVID-19 later tested positive for the virus.

But there are several ways to explain that outcome, scientists cautioned.

While it is not impossible that these individuals became infected a second time, there is little evidence this is what happened.

More likely, said Balloux, is that the virus never completely disappeared in the first place and remains -- dormant and asymptomatic -- as a "chronic infection", like herpes.

As tests for live virus and antibodies have not yet been perfected, it is also possible that these patients at some point tested "false negative" when in fact they had not rid themselves of the pathogen.

"That suggests that people remain infected for a long time -- several weeks," Balloux added. "That is not ideal."

Another pre-publication study that looked at 175 recovered patients in Shanghai showed different concentrations of protective antibodies 10 to 15 days after the onset of symptoms.

"But whether that antibody response actually means immunity is a separate question," commented Maria Van Kerhove, Technical Lead of the WHO Emergencies Programme.

"That's something we really need to better understand -- what does that antibody response look like in terms of immunity."

Indeed, a host of questions remain.

"We are at the stage of asking whether someone who has overcome COVID-19 is really that protected," said Jean-Francois Delfraissy, president of France's official science advisory board.

For Tangy, an even grimmer reality cannot be excluded.

"It is possible that the antibodies that someone develops against the virus could actually increase the risk of the disease becoming worse," he said, noting that the most serious symptoms come later, after the patient had formed antibodies.

For the moment, it is also unclear whose antibodies are more potent in beating back the disease: someone who nearly died, or someone with only light symptoms or even no symptoms at all. And does age make a difference?

Faced with all these uncertainties, some experts have doubts about the wisdom of persuing a "herd immunity" strategy such that the virus -- unable to find new victims -- peters out by itself when a majority of the population is immune.

"The only real solution for now is a vaccine," Archie Clements, a professor at Curtin University in Perth Australia, told AFP.

At the same time, laboratories are developing a slew of antibody tests to see what proportion of the population in different countries and regions have been contaminated.

Such an approach has been favoured in Britain and Finland, while in Germany some experts have floated the idea of an "immunity passport" that would allow people to go back to work.

"It's too premature at this point," said Saad Omer, a professor of infectious diseases at the Yale School of Medicine.

"We should be able to get clearer data very quickly -- in a couple of months -- when there will be reliable antibody tests with sensitivity and specificity."

One concern is "false positives" caused by the tests detecting antibodies unrelated to COVID-19.

The idea of immunity passports or certificates also raises ethical questions, researchers say.

"People who absolutely need to work -- to feed their families, for example -- could try to get infected," Balloux.

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Agencies
May 22,2020

Kochi, May 22: During the nationwide COVID-19 lockdown, Kerala recorded the highest number of cyber attacks followed by Punjab and Tamil Nadu, a study by anti-virus software firm K7 Computing said on Thursday.

In a statement issued in Chennai, the company said its K7 Computing's Cyber Threat Report, a comprehensive analysis of cyber attacks during the lockdown has found that Kerala recorded the highest number of cyber attacks during this period. The report analyses various cyber attacks within India during the pandemic and reveals that threat actors targeted the state with COVID-themed attacks aimed at exploiting user trust.

In Kerala, regions like Kottayam, Kannur, Kollam, and Kochi saw the highest hits with 462, 374, 236, and 147 attacks respectively, while the state as a whole saw around 2,000 attacks during the period - the highest thus far in the country.

This was followed by Punjab with 207 attacks and Tamil Nadu with 184 attacks, the company said.

The sudden surge in the frequency of attacks witnessed from February 2020 to mid-April 2020 indicates that scamsters across the world were exploiting the widespread panic around coronavirus at both the individual and corporate level.

These attacks aimed to compromise computers and mobile devices to gain access to users' confidential data, banking details, and cryptocurrency accounts.

The key threats seen during this period ranged from phishing attacks to rogue apps disguised as COVID-19 information apps that targeted users' sensitive data. Phishing attacks were noticed more in Tier-II and Tier-III cities while the metros fared better. Smaller cities saw over 250 attacks being blocked per 10,000 users.

Users from Ghaziabad and Lucknow seem to have faced almost 6 and 4 times the number of attacks as Bengaluru users.

According to the statement, a majority of the recorded attacks were phishing attacks with sophisticated campaigns that could easily snare even the most educated users. These attacks were aimed at heightening users' fears and creating a sense of urgency to take action.

K7 Labs noticed phishing attacks where scamsters posed as representatives of the United States Department of Treasury, the World Health Organization (WHO), and the Centres for Disease Control and Prevention (CDC), the company said.

Users were encouraged to visit links that would automatically download malware on the host computer such as the Agent Tesla keylogger or Lokibot information-stealing malware, infamous banking Trojans such as Trickbot or Zeus Sphinx, and even disastrous ransomware.

Other attacks included infected COVID-19 Android apps like CoronaSafetyMask that scam users with promises of masks for an upfront payment; the spyware app Project Spy; and seemingly genuine apps that are infected with dangerous malware like banking Trojans such as Ginp, Anubis and Cerberus.

"Covid-19 has created an ideal situation for various threat actors to target individuals and enterprises alike. The panic caused by the stringent lockdown measures and rapid spread of this virus has left many people looking for more information on the situation," J. Kesavardhanan, Founder and CEO of K7 Computing was quoted as saying in the statement.

"Threat actors exploit this fear to their advantage and scam users into downloading malicious software and divulging sensitive information like banking codes. The need to be cyber cautious has never been greater. This is more so in the case of corporates who have adopted a work from home policy hurriedly without adequate cyber hygiene. We have seen an increase in attacks on enterprises and SME employees as well," he added.

Such attacks are expected to continue till normalcy returns. Social engineering attacks targeted at winning users' trust will gain momentum.

Healthcare institutions, well-known government offices, and international organisations will continue to be a prime target throughout the pandemic, the statement said.

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News Network
May 6,2020

Hyderabad, May 6: Away from city lights, two hours before Sunrise, people in India and across the world can witness Annual Meteor Shower called Eta Aquarids till May 28.

Observed since time immemorial, Meteor shower are commonly known as shooting stars which are nothing but dust flakes of comet/asteroid entering earth atmosphere.

This Annual Eta Aquarids Meteor Shower peaked on Wednesday at 02.30 am on Wednesday whereas presence of Full Moon was an obstacle outshining bright streaks of lights of this meteor shower zipping across the South Eastern sky.

As this meteor shower is active till May 28, people can still watch this celestial spectacle in early morning every day, Planetary Society of India (PSI) Director N Sri Raghunandan Kumar interacting with UNI said.

As per International Meteor Organization (IMO), 50 meteors per hour are expected to be seen on day of peak today. And this number would vary as days pass on till May 28 while earth passes through dust cloud of comet debris in its orbit.

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Agencies
March 16,2020

While Google is still working on a coronavirus screening and tracking website, Microsoft Bing team has already launched a web portal for tracking COVID-19 infections worldwide.

The website, accessible at bing.com/covid, provides up-to-date infection statistics for each country.

The COVID-19 Tracker currently lists 168,835 as total confirmed cases, 84,558 active cases, 77,761 recovered cases and 6,516 deaths.

There are at least 3,244 confirmed cases of novel coronavirus in the US and at least 61 deaths.

"Lots of Bing folks worked (from home) this past week to create a mapping and authoritative news resource for COVID19 info," Michael Schechter, General Manager for Bing Growth and Distribution at Microsoft, was quoted as saying in a ZDNet report on Sunday.

An interactive map allows site visitors to click on the country to see the specific number of cases and related articles from a variety of publishers.

Data is being aggregated from sources like the World Health Organization (WHO), the US Centers for Disease Control and Prevention (CDC), and the European Centre for Disease Prevention and Control (ECDC).

Microsoft announced the website two days after US President Donald Trump said Google has begun working on COVID-19-related portal for US citizens.

Google's website is being built by Verily, a subsidiary of Alphabet focused on healthcare services.

"More than 1,700 engineers are currently working on the site", Trump said during a press briefing last week.

The tool will triage people who are concerned about their COVID-19 risk into testing sites based on guidance from public health officials and test availability.

Initially, there was some confusion on Google's coronavirus portal but the company later announced that it is "partnering with the US Government in developing a nationwide website that includes information about COVID-19 symptoms, risk, and testing information."

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