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 a respiratory illness that ranges from common colds/flu too 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.
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 according to WHO.
Although symptoms are often mild i.e. 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.
The risk of death has been difficult to calculate, as it relies on accurate numbers of those who have symptoms but survive. A study of people who contracted COVID-19 in Wuhan suggests that the risk of death increases with age, and is also higher for those who have diabetes, disease, blood clotting problems, or have shown signs of sepsis.
How& Where did COVID-19 start?
It is believed that the disease 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.
The hunt for the animal source of COVID-19 is still unknown, although there are some strong contenders. A team of virologists at the Wuhan Institute for Virology released a detailed paper showing that the new Coronavirus genetic make-up is 96 per cent identical to that of a coronavirus found in bats, while a study published on March 26 2020 [https://https://www.nature.com/articles/s41586-020-2169-0] argues that genetic sequences of coronavirus in pangolin are between 88.5 and 92.4 per cent similar to the human virus. Some early cases of COVID-19, however, appeared 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, 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.
When did COVID-19 start?
Cases of COVID-19 first emerged in late 2019, when a mysterious illness was reported in Wuhan, China. The cause of the disease was soon confirmed as a new kind of coronavirus and the infection has since spread to many countries around the world and become a pandemic.
What started as an epidemic mainly limited to China has now become a truly global pandemic. There have now been over 884, 997 confirmed cases and 44, 200 deaths (as of April 1, 2020), according to the John Hopkins University, which collates information from national and international health authorities. The disease has been detected in more than 202 countries and territories, with the US, Italy, Spain, France, UK, Germany and Iran experiencing the most widespread outbreaks outside of China
On 11 February the World Health Organization announced that the official name would be COVID-19, a shortened version of coronavirus disease 2019. The WHO refers to the specific virus that causes this disease as the COVID-19 virus. This is not the formal name for the virus – the International Committee on Taxonomy of Viruses calls it the “severe acute respiratory syndrome coronavirus 2”, or SARS-CoV-2 because it is related to the virus that caused the SARS outbreak in 2003. However, to avoid confusion with SARS the WHO calls it the COVID-19 virus when communicating with the public.
Early in the outbreak, the virus was called 2019-nCoV by the WHO. The virus is also often referred to as the novel coronavirus, 2019 coronavirus or just the coronavirus.
What are the symptoms of COVID-19?
COVID-19 shares many of its symptoms with the flu/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 symptoms for COVID-19 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 from a dry cough. For this reason, anyone with a fever or a new, continuous cough 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 i.e. a thick mucus from within the lungs. Other rarer symptoms include shortness of breath, muscle pain, sore throats, headaches or chills, loss of smell or taste. According to the WHO, symptoms tend to appear between five and six days after infection.
The spread of COVID-19
COVID-19 is a respiratory illness and is largely spread via droplets in the air. These are typically expelled when an infected person coughs or sneezes. Once symptoms develop, a person’s viral load declines steadily, and they become increasingly less infectious. However, people appear to keep shedding the virus for around 14 days after they recover from COVID-19, both in their saliva and stools. This means that even once a person’s symptoms have cleared, it may still be possible to infect other people.
People with mild or no symptoms can have a very high viral load in their upper respiratory tracts, meaning they can shed the virus through spitting, touching their mouths or noses and then a surface, or possibly talking. The new coronavirus has also been found to persist for up to 24hours on metallic surfaces and 50hours on plastic/fabric surfaces, this means these virus particles could possibly still infect other people.
How far has COVID-19 spread?
China has borne the brunt of COVID-19 infections (so far). As of April 1, 2020, Chinese health authorities had acknowledged over 82,240 cases and 3,312 deaths most of them within the province of Hubei. On March 17, China recorded just 39 new cases of the virus which is 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. Most of the country's new cases are imported from elsewhere in the world and for now, at least, it appears that China has its outbreak under control.
But while the outbreak is slowing down in China, the outbreak started picking up in the rest of the world. There are no confirmed cases in at least 200 countries and territories. Outside of China, the US is now the new epicentre of the COVID-19 outbreak with the highest number of cases. The most powerful country which has been criticised for its slow roll-out of testing and confused approach to the crisis now has more than 189,661 confirmed infections and 4,097 deaths (as of April 1, 2020).
Italy has seen the highest number of cases in Europe and the second-largest outbreak outside China, with 105,792 confirmed infections and 12,428 deaths. 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 more than 102,136 confirmed infections and 9,053 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 more than 74,508 cases and 821 deaths, with the state of Bavaria implementing a full lockdown although for now its case fatality rate i.e. the number of confirmed coronavirus deaths compared to confirmed infections is much lower than elsewhere in Europe.
In the UK(29,474 confirmed cases and 2,352deaths), the government has shut schools, pubs, restaurants, bars cafés and all non-essential shops. People with the main coronavirus symptoms – a fever or dry cough – are required to stay at home for seven days while households in which at least one person is displaying symptoms should quarantine themselves for 14 days. Among the high profile, people who have tested positive for the virus are Prince Charles, the prime minister Boris Johnson and health secretary Matt Hancock, both are currently self-isolating while working on the UK's response from home.
Other countries with high COVID-19 outbreak are France with 52,128 confirmed cases and 3523 deaths, Iran with 47,593 confirmed cases and 3,036deaths
The world has recorded more than 884,997 confirmed cases and 44,200deaths(as of 1300 GMT April 1 2020) https://www.worldometers.info/coronavirus/. While the number of new cases continues to rise sharply, the good news is that people are also recovering from the infection. Globally, 185,196 people have recovered from COVID-19 i.e. about 21 per cent of all of the people who had confirmed infections, although the true number of coronavirus cases is speculated to be much higher.
What are Confirmed COVID-19 Cases?
The WHO’s definition of a confirmed case of COVID-19 is a person shown by laboratory testing to be infected with the virus, irrespective of clinical signs and symptoms. However, some reported case numbers from China have included people with symptoms of COVID-19, but without laboratory confirmation.
The most commonly reported symptoms to include fever, dry cough, tiredness and a sore throat. In the most severe cases, people with the virus can develop difficulty breathing, and may ultimately experience organ failure. Some cases are fatal.
The virus can also be asymptomatic, causing no noticeable illness in some people – but these people are still contagious and can spread the virus.
On 11 March, the WHO announced that the outbreak should be considered a pandemic i.e. a term that has no universally agreed definition, but means that multiple countries are seeing sustained transmission between people of an outbreak causing disease or death.
The Chinese government responded to the initial outbreak by placing Wuhan and nearby cities under a de-facto quarantine encompassing roughly 50 million people in Hubei province. This quarantine is now slowly being lifted after three months of a total lockdown, as authorities watch to see whether cases will rise again.
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 12-18 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 to expect next?
WHO chief Tedros A. 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.
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This article (original version) was published at 14:30 GMT on April 1, 2020.
By Ruzeki 
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