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What Is Coronavirus & What Happens Now It Is a Pandemic

The disease appears to have originated from a Wuhan seafood market where wild animals, including marmots, birds, rabbits, bats and snakes, are traded illegally. Coronaviruses are known to jump from animals to humans, so it’s thought that the first people infected with the disease – a group primarily made up of stallholders from the seafood market – contracted it from contact with animals.

Although an initial analysis of the virus that causes Covid-19 suggested it was similar to viruses seen in snakes, the hunt for the animal source of Covid-19 is still on. A team of virologists at the Wuhan Institute for Virology released a detailed paper showing that the new coronaviruses’ genetic makeup is 96 per cent identical to that of a coronavirus found in bats, while an as-yet unpublished study argues that genetic sequences of coronavirus in pangolins are 99 per cent similar to the human virus. Some early cases of Covid-19, however, appear to have inflicted people with no link to the Wuhan market at all, suggesting that the initial route of human infection may pre-date the market cases.

The Wuhan market was shut down for inspection and cleaning on January 1, but by then it appears that Covid-19 was already starting to spread beyond the market itself. On January 21, the WHO Western Pacific office said the disease was also being transmitted between humans – evidence of which is apparent after medical staff became infected with the virus. Since then, evidence of widespread human-to-human transmission outside of China has been well established, making chances of containing the virus much harder.

What exactly is Covid-19?

Coronaviruses are a large group of viruses that are known to infect both humans and animals, and in humans cause respiratory illness that range from common colds to much more serious infections. The most well-known case of a coronavirus epidemic was Severe Acute Respiratory Syndrome (Sars), which, after first being detected in southern China in 2002, went on to affect 26 countries and resulted in more than 8,000 cases and 774 deaths. The number of people infected with Covid-19 has now well surpassed those hit with Sars.

While the cause of the current outbreak was initially unknown, on January 7 Chinese health authorities identified that it was caused by to a strain of coronavirus that hadn’t been encountered in humans before. Five days later the Chinese government shared the genetic sequence of the virus so that other countries could develop their own diagnostic kits. That virus is now called Sars-CoV-2.

Although symptoms of coronaviruses are often mild – the most common symptoms are a fever and dry cough – in some cases they lead to more serious respiratory tract illness including pneumonia and bronchitis. These can be particularly dangerous in older patients, or people who have existing health conditions, and this appears to be the case with Covid-19. A study of 44,415 early Chinese Covid-19 patients found that 81 per cent of people with confirmed infections experienced only mild symptoms. Of the remaining cases, 14 per cent were in a severe condition while five per cent of people were critical cases, suffering from respiratory failure, septic shock or multiple organ failure. In the Chinese study, 2.3 per cent of all confirmed cases died, although the actual death rate is probably much lower as many more people will have been infected with the virus than tested positive.

How far has it spread?

China has borne the brunt of Covid-19 infections (so far). As of March 11, Chinese health authorities had acknowledged over 81,250 cases and 3,253 deaths – most of them within the province of Hubei. On March 17, China recorded just 39 new cases of the virus – a remarkable slowdown for a country which, at the peak of its outbreak in mid-February, saw more than 5,000 cases in a single day.

But while things were slowing down in China, the outbreak started picking up in the rest of the world. There are now confirmed cases in at least 150 countries and territories. Outside of China, Italy has seen the highest number of cases, with 47,035 confirmed infections, mostly in the north of the country, and 4,032 deaths – more than in China. The entire country is now on lockdown after the quarantine covering the north of the country was extended on March 9.

Spain is also in the grip of a significant outbreak. The country has 20,410 confirmed infections and 1,043 deaths – the second-highest number within Europe. There, citizens are under lockdown, with the government shutting all schools, bars, restaurants and non-essential supermarkets down. People are only allowed to leave their homes to buy food or to go to work. Germany has 19,711 cases and 53 deaths, with the state of Bavaria implementing a full lockdown.

Iran, too, is seeing a surge in cases. The country has confirmed at least 1,433 deaths and 19,664 cases. In the US, there have been more than 14,631 cases and 210 deaths – 74 of them in Washington State, which has become the epicentre of the US outbreak.

While the number of new cases continues to rise sharply, people are also recovering from the infection. Globally, 84,960 people have recovered from Covid-19 – about 32 per cent of all of the people who had confirmed infections, although the true number of coronavirus cases will be much higher.

What’s the latest in the UK?

As of March 18, the UK has reported 3,983 confirmed Covid-19 infections and 177 deaths. On March 16, prime minister Boris Johnson led the first daily coronavirus press conference, saying that the government now advised all UK residents to avoid non-essential social contact and travel where possible. On Friday March 20 this was extended to include a shutdown of all bars, pubs, cafes and restaurants in the UK. From the same day all schools in England, Scotland and Wales were shut until further notice. Only vulnerable children, or those who are the sons and daughters of employees in the NHS or other key industries, will be permitted to remain at school.

People who currently live alone are recommended to self-isolate for seven days if they develop a fever or persistent dry cough – the two most common symptoms of coronavirus. For families and other people who live together, the advice is that the entire household should self-isolate if any member develops either of those symptoms. This strategy is part of the government’s ‘delay phase‘ plan to flatten the peak of the virus and reduce the burden on the NHS.

A key part of this plan is shielding those who are most vulnerable to Covid-19: people older than 70, or those who have underlying health conditions. The prime minister said that this shielding may last as long as 12 weeks in order to ensure that the peak of the outbreak has passed, although modelling from Imperial College London suggests that these measures may have to be in place for as long as 18 months. Despite these measures, some have been critical that the government’s stance doesn’t go far enough. Italy and Spain have both in place widespread lockdowns, while South Korea has rolled-out extremely comprehensive testing for many of its population.

The outbreak has also had a serious impact on the UK’s stock market. On March 9 the FTSE 100 fell by more than eight per cent, knocking billions off the value of major UK companies. Cinema changes Odeon, Cineworld and Vue closed their doors while Euro 2020 was also delayed until 2021, which is an added blow to broadcasters, particularly ITV.

What are the symptoms of Covid-19?

Covid-19 shares many of its symptoms with the flu or common cold, although there are certain symptoms common to flu and colds that are not usually seen in Covid-19. People with confirmed cases of Covid-19 rarely suffer from a runny nose, for instance.

The most common Covid-19 symptoms are a fever and a dry cough. Of 55,924 early Chinese cases of the disease, nearly 90 per cent of patients experienced a fever and just over two-thirds suffered with a dry cough. That’s why the UK government is advising anyone with a high temperature or a new, continuous cough to stay at home for seven days or, if they live with other people, for the entire household to isolate for 14 days from the first onset of symptoms.

Other Covid-19 symptoms are less common. Just under 40 per cent of people with the disease experience fatigue, while a third of people cough up sputum – a thick mucus from within the lungs. Other rarer symptoms include shortness of breath, muscle pain, sore throats, headaches or chills. According to the WHO, symptoms tend to appear between five and six days after infection.

What’s happening with a vaccine?

A vaccine for Covid-19 isn’t around the corner. Bringing vaccines to the market is a notoriously slow process and any potential vaccine will have to pass multiple stages of testing for safety and effectiveness. And once we know a vaccine is safe, we will also need to manufacture it at a scale high enough to use across the world. It’s likely that any vaccine is around 18 months away.

That said, there is lots of work being done to develop a vaccine for Covid-19. The pharmaceutical firm Sanofi is trying to build on its already-approved flu vaccine and turn it into something suitable to treat Covid-19. Other approaches – such as one being trialled by the University of Oxford – are focusing on the external spike proteins on the Covid-19 virus as a way to target vaccines.

But accelerating these efforts will require funding. The Coalition for Epidemic Preparedness Innovations (CEPI) has called for $2 billion in funding to support the development of new coronavirus vaccines.

What’s going to happen next?

WHO chief Tedros Adhanom Ghebreyesus has warned that the window of opportunity to contain Covid-19 is “narrowing”. Recent outbreaks in Italy and Iran, which so far have no clear link to China, pose a significant challenge to health authorities trying to stop the spread of the virus.

After initially delaying the decision, on March 11, the WHO declared the Covid-19 outbreak a pandemic. The agency cited the rapid growth of cases outside of China and the global spread of the disease as reasons behind the designation. In January, it also declared the outbreak a “public health emergency of international concern” – the highest category of warning for an infectious disease outbreak.

Since 2009 there have only been five declarations of international public health emergencies: the swine flu pandemic in 2009, a polio outbreak in 2014, the Western Africa Ebola outbreak in 2014, the Zika virus outbreak in 2015 and another Ebola outbreak in the Democratic Republic of the Congo in 2019.

Matt Reynolds is WIRED’s science editor. He tweets from @mattsreynolds1

Source: What is coronavirus and what happens now it is a pandemic?

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And why the disease first appeared in China. NOTE: As our expert Peter Li points out in the video, “The majority of the people in China do not eat wildlife animals. Those people who consume these wildlife animals are the rich and the powerful –a small minority.” This video explains how the people of China are themselves victims of the conditions that led to coronavirus. The virus is affecting many different countries and cultures, and there is never justification for xenophobia or racism. You can find further reading on this on Vox: https://www.vox.com/2020/2/7/21126758… https://www.vox.com/policy-and-politi… https://www.vox.com/identities/2020/3…

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Can You Get Coronavirus Twice? How Long Are You Immune After COVID-19?

A sequel to a movie that you didn’t want to see in the first place is one thing, like Ghost Rider 2 after Ghost Rider. A sequel to having a COVID-19 infection would be something completely different.

You may think that the one “positive” of testing positive for the COVID-19 causing coronavirus (SARS-CoV2) and surviving would be that you won’t get infected by that virus again. At least not during this pandemic. Ah, but is this assumption really true? Will you indeed be immune to the SARS-CoV2 after you’ve recovered from a COVID-19 infection? Some reports out of Japan and China seem to suggest otherwise.

For example, Daniel Leussink and Rocky Swift reported for Reuters about a female tour bus guide in Japan who tested positive for the virus after recovering from a COVID-19 infection. Here is a UNTV news report on the case:

                               

Does this case actually prove that re-infection with the virus is possible? Or was this just a mistake in the testing? Or did the person have a particularly weak immune system so that she couldn’t generate immunity? After all, one case can be an accident, an aberration, an anomaly, an aardvark in a sea of anemone.

Well, oops something like this happened again, according to a more recent NHK-World Japan report. This time it was a man in his 70’s, who first tested positive for SARS-CoV2 on February 14 while on a Diamond Princess cruise ship. After being transferred to a medical facility in Tokyo, he stayed there until testing negative for the virus. On March 2, he left the facility and traveled home via public transportation. However, the man eventually began feeling sick with a fever, which prompted him to go to a hospital on March 13. The following day he tested positive for the virus again.

Then there’s the February 14 article from Caixin, a Beijing, China-based media group, that was entitled “14% of Recovered Covid-19 Patients in Guangdong Tested Positive Again.” Umm, 14% would seem more like an “ooop” than an “ooops.” This CGTN news warned of such reinfection possibilities:

                           

Remember though, these are news reports and not scientific studies yet. While the reappearance of Nicholas Cage with a flaming skull riding a motorcycle may not call for additional scientific studies, all of these cases certainly do. First, scientists need to confirm whether the test results were indeed accurate. Remember, no test is perfect. If people can screw up a drink order, they can certainly mess up a medical test. Even if a test is performed properly, you could still get a positive result when you don’t actually have an infection. On the flip side, just because you test negative doesn’t necessarily mean that there is no way that you are carrying the virus. That’s why a doctor may test you multiple times to be sure of a result.

Secondly, doctors and other scientists need to double-check or triple-check that each of these patients actually got re-infected with the virus rather than had an infection that simply lasted a long time. What if, for example, the cruise passenger and the tour bus guide each had fairly long infections and just happened to have intervening false negative test results? The tests could have simply been like commercial breaks in the middle of a single long episode of a television show.

Third of all, the amount of immunity that you build up after being exposed to any virus depends on not only virus itself but surprise, surprise your immune system and its response. When your immune system sees a particular virus for the first time, it can essentially get caught with its pants down, not ready to defend your body against this new invader. However, exposure to the virus either through a vaccine or getting infected may train your immune system so that, borrowing the words of former President George W. Bush, “fool me once, shame on — shame on you. Fool me — you can’t get fooled again.” If strong enough, your immune system then may be ready with proper defenses next time the virus comes calling. Could the cases of reinfection then be examples of people who happened to have weaker immune systems?

Or are these cases any indication that our immune systems may not be able to consistently build up enough protection against SARS-CoV2? Well, a review article published in January 2020 in the Journal of Medical Virology summarizes much of what is known about your immune system’s response to various types of coronavirus. As you can see, this involves a complex orchestra of different cells and chemicals. Therefore, the immune response to one virus won’t necessarily be the same as to another virus, even if both viruses were different types of coronaviruses. All of this also depends on how strong your immune system may be and how well your immune system recognizes an invader like SARS-CoV2.

Plus, your immune system has got to remember the virus. Over time, immunity may fade, allowing the virus to reinfect you. It’s like when you get back together with an ex after you have forgotten how terrible you are for each other. The question then is how long can your immune system remember SARS-CoV2?

With SARS-CoV2 having emerged so quickly, there just haven’t been enough studies yet on how your immune system may react specifically to SARS-CoV2 and how this may differ from person to person. Therefore, we have to rely on studies of other coronaviruses for now. The closest approximation is probably the even more evil cousin of SARS-CoV2, the original SARS virus that caused the outbreak of 2002-2003.

In a study published in a 2007 issue of Emerging Infectious Diseases, a research team from the Shanxi Provincial Center for Disease Control and Prevention in Taiyuan, China, followed 176 patients who had had severe acute respiratory syndrome (SARS). On average, SARS-specific antibodies remained at the same level in a patient’s blood for about two years. Then, during the third year after infection, antibody levels tended to drop precipitously. This suggests that immunity to the SARS virus may remain for two to three years with reinfection possible after three years.

Keep in mind though that antibody levels do not always correlate with immunity. They can be like selfies on Instagram, only indirect measures of what’s really going on at a deeper level. Some people may have immunity against a virus without detectable antibody levels, and some people may be very susceptible to infection even though antibodies are present. The only way to have determined if the patients actually had immunity against the SARS virus would have been to have re-exposed them to the virus and checked what happened. And that would have been a horrible experiment to do.

The other question is how many different versions of SARS-CoV2 may be running around, or rather spreading around since viruses don’t have little feet and little sneakers. It’s difficult to answer this question for sure without more thorough and widespread testing. According to a study published in the journal National Science Review, an analysis of samples from 103 COVID-19 cases suggests that at least two different versions of SARS-CoV2 are circulating. This doesn’t necessarily mean that these versions are so different that immunity to one version doesn’t mean immunity to another. Regardless, things may evolve in the near future. Viruses can be like the characters in Game of Thrones or an actor in a Broadway show, changing rapidly. Over time, the new coronavirus could possibly mutate to the point that new versions are no longer as recognizable by your immune system as the original version. After all, mutations are probably what allowed the virus to jump from another animal to humans.

Not knowing exactly how immunity against SARS-CoV2 works and how long it may last throws a gigantic wrench into public health planning. Many trying to predict the course of the pandemic have been assuming that once a high enough proportion of the overall population has been infected and has become immune, the pandemic will subside. Herd immunity is the percentage of the overall population that is immune to a given pathogen. When this percentage gets high enough, the virus will struggle to find more susceptible people to infect, sort of like trying to sell Justin Bieber T-shirts in a crowd when most of the people are already wearing such shirts. The belief is that when around 70% of the population is immune to the virus, SARS-CoV2 will struggle to continue transmitting.

However, things could change substantially if people can actually get re-infected with the virus or different enough versions of the virus end up circulating. Such possibilities would be yet more reasons to question the “herd immunity” approach to controlling the pandemic that’s currently being discussed in the U.K. and described by Sarah Boseley for The Guardian. Since there is no vaccine available against SARS-CoV2, there is actually talk of allowing those with stronger immune systems to get infected to achieve the 70% or so herd immunity threshold. Huh?

This strategy would make sense except for the fact that it doesn’t. First of all, those who get infected could end up having serious consequences such as death, which is typically a very serious consequence. This would be reminiscent of the saying that “the operation was successful, but the patient died.” Allowing people to become infected by a potentially deadly virus is always a risky proposition, sort of like playing roulette when your lungs are on the betting table. So far, the COVID-19 case-fatality rate seems to be somewhere between 1% and 3.4%. This isn’t as high as the rate for SARS but nonetheless significantly higher than that of a bad flu season.

Secondly, this herd immunity strategy depends on people not getting re-infected with the virus. But with the aforementioned reports from Japan and China, you have to wonder if the strategy is not a “herd immunity” strategy but rather a “herd immunity maybe” strategy to borrow the words of Carly Rae Jepsen. “Maybe” may work to some degree with flirting and dating but not when lives are at stake.

Third of all, this strategy assumes that people will not leave or enter the U.K. That may work only if you want to completely eliminate travel to and from the country.

Finally, such a strategy would run counter to other mitigation strategies such as social distancing as indicated by the following tweet:

                           

Uh, U.K., would this really be O.K.?

All of this is a reminder that scientists do not yet know enough about this new coronavirus. What percentage of people become immune to the virus if exposed? How strong is the immunity? Will it actually prevent reinfection? How long would this immunity last? Is it two years as the SARS study hints at or could it be much shorter than that? How does all of this vary from person to person? How many different versions of the virus may end up circulating? As the Internet meme goes, I and many other scientists have so many questions.

Therefore, if you do get exposed to the virus and recover, don’t view it as a free pass to start hugging strangers, digging your fingers deep into your nose like you are looking for pocket change, and licking door knobs. Keep doing what everyone else should be doing such as social distancing, washing your hands frequently and thoroughly, keeping your filthy fingers from gravitating towards your gigantic face, and actively disinfecting surfaces, objects, and that enormous BTS statue that you have in your living room. Just because you survived the first infection, doesn’t necessarily mean that future exposures and possible infections will end up OK. As you know, sequels don’t always have the same endings.

Follow me on Twitter or LinkedIn. Check out my website.

I am a writer, journalist, professor, systems modeler, computational and digital health expert, avocado-eater, and entrepreneur, not always in that order. Currently, I am a Professor of Health Policy and Management at the City University of New York (CUNY), Executive Director of PHICOR (@PHICORteam), Associate Professor at the Johns Hopkins Carey Business School, and founder and CEO of Symsilico. My previous positions include serving as Executive Director of the Global Obesity Prevention Center (GOPC) at Johns Hopkins University, Associate Professor of International Health at the Johns Hopkins Bloomberg School of Public Health, Associate Professor of Medicine and Biomedical Informatics at the University of Pittsburgh, and Senior Manager at Quintiles Transnational, working in biotechnology equity research at Montgomery Securities, and co-founding a biotechnology/bioinformatics company. My work involves developing computational approaches, models, and tools to help health and healthcare decision makers in all continents (except for Antarctica) and has been supported by a wide variety of sponsors such as the Bill and Melinda Gates Foundation, the NIH, AHRQ, CDC, UNICEF, USAID and the Global Fund. I have authored over 200 scientific publications and three books. Follow me on Twitter (@bruce_y_lee) but don’t ask me if I know martial arts

Source: Can You Get Coronavirus Twice? How Long Are You Immune After COVID-19?

Coronaviruses (CoV) are a family of viruses that cause sicknesses like the common cold, as well as more severe diseases, such as Middle East Respiratory Syndrome and Severe Acute Respiratory Syndrome. A novel coronavirus (nCoV) is a new strain – one that hasn’t previously been recognized in humans. Coronaviruses cause diseases in mammals and birds. A zoonotic virus is one that is transmitted between animals and people. When a virus circulating in animal populations infects people, this is termed a “spillover event”. How does CoVID-19 affect the body? The virus is fitted with protein spikes sticking out of the envelope that forms the surface and houses a core of genetic material. Any virus that enters your body looks for cells with compatible receptors – ones that allow it to invade the cell. Once they find the right cell, they enter and use the cell’s replication machinery to create copies of themselves. It is likely that COVID-19 uses the same receptor as SARS – found in both lungs and small intestines. It is thought that CoVID-19 shares many similarities with SARS, which has three phases of attack: viral replication, hyper-reactivity of the immune system, and finally pulmonary destruction. Early on in infection, the coronavirus invades two types of cells in the lungs – mucus and cilia cells. Mucus keeps your lungs from drying out and protects them from pathogens. Cilia beat the mucus towards the exterior of your body, clearing debris – including viruses! – out of your lungs. Cilia cells were the preferred hosts of SARS-CoV, and are likely the preferred hosts of the new coronavirus. When these cells die, they slough off into your airways, filling them with debris and fluid. Symptoms include a fever, cough, and breathing difficulties. Many of those infected get pneumonia in both their lungs. Enter the immune system. Immune cells recognize the virus and flood into the lungs. The lung tissue becomes inflamed. During normal immune function, the inflammatory process is highly regulated and is confined to infected areas. However, sometimes the immune system overreacts, and this results in damage to healthy tissue. More cells die and slough off into the lungs, further clogging them and worsening the pneumonia. As damage to the lungs increases, stage three begins, potentially resulting in respiratory failure. Patients that reach this stage of infection can incur permanent lung damage or even die. We see the same lesions in the lungs of those infected by the novel coronavirus as those with SARS. SARS creates holes in the lungs, so they look honeycomb-like. This is probably due to the aforementioned over-reactive immune response, which affects tissue both infected and healthy and creates scars that stiffen the lungs. As such, some patients may require ventilators to aid breathing. The inflammation also results in more permeable alveoli. This is the location of the thin interface of gas exchange, where your lungs replace carbon dioxide in your blood with fresh oxygen you just inhaled. Increased permeability causes fluid to leak into the lungs. This decreases the lungs’ ability to oxygenate blood, and in severe cases, floods them so that you become unable to breathe. Sometimes, this can be fatal. The immune system’s over-reaction can also cause another kind of damage. Proteins called cytokines are the immune system’s alarm system, recruiting immune cells to the infection site. Over-production of cytokines can result in a cytokine storm, where there is large-scale inflammation in the body. Blood vessels become more permeable and fluid seeps out. This makes it difficult for blood and oxygen to reach the rest of the body and can result in multi-organ failure. This has happened in the most severe cases of CoVid-19. Although there are no specific treatments for coronaviruses, symptoms can be treated through supportive care. Also, vaccines are currently in development. What can you do to protect yourself from CoVid-19? Basic protocol comes down to regular hand washing, avoiding close contact with anyone coughing or sneezing, avoiding unnecessary contact with animals, washing hands after contact with animals, thoroughly cooking meat and eggs prior to consumption, and covering your mouth and nose while coughing or sneezing. Respiratory viruses are typically transmitted via droplets in sneezes or coughs of those infected, so preventing their travel stops the spread of disease. Alveoli model from: https://www.turbosquid.com/3d-models/…

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