The Coronavirus Epidemic – How Worried Should We Be?
By: Dr Nigel Whittle
Head of Medical & Healthcare
31st January 2020
4 minute read
The current epidemic results from infection by a coronavirus, one of a family of viruses that infect the nose, sinuses, or upper throat. Infection causes illnesses that range from the common cold to pneumonia and severe acute respiratory syndrome (SARS). The virus is named after its characteristic shape, which under an electron microscope looks like a royal crown with bulbous protrusions around it.1
Most such viruses are not dangerous. However, in early January 2020 the WHO identified a previously unknown type: 2019 novel coronavirus (2019-nCoV), a new strain not previously seen in humans. The first human cases had in fact been identified in the Chinese city of Wuhan in December 2019, before the cause was known. Initial symptoms of the viral infection included a fever, cough and difficulty in breathing, but in more severe cases the infection led to pneumonia, kidney failure and death.
By mid-January there were over 300 confirmed cases in China and a death count that was in the single digits but rising steadily. Many of those initially infected either worked or shopped in a large market in central Wuhan, which also sold live and newly slaughtered animals, leading to the assumption that the virus had jumped species, a not uncommon phenomenon. Interestingly, a genetically similar viral strain had been identified in a local breed of bats a few years’ previously, suggesting that the virus has jumped at least two species.
Spread of the virus
It is now clear that the virus is capable of person-to-person spreading. Scientists at Imperial College recently estimated that about 100,000 people around the world may already be infected with the new coronavirus and that each infected patient can infect on average 2.6 others – about the same rate as in annual influenza outbreaks. Worryingly there is concern that the coronavirus can be passed on during the disease’s incubation period, which means that someone who is ill but not yet displaying any symptoms could transmit the infection. A current count of more than 100 deaths out of 6,000 reported cases implies a 1.7% mortality rate, compared with seasonal influenza (which causes about 400,000 deaths each year globally) with a mortality rate well below 1%.
First lines of defence
One of the first lines of defence is monitoring airline passengers flying in from areas where the virus is active, often using thermal imaging cameras to detect fever, in an attempt to identify people who have symptoms. The problem is that only those who are already ill will be picked up, although it is thought that the incubation period (how long it takes for symptoms to appear after catching the infection) is days, rather than weeks. More draconian measures such as those instigated by China to effectively quarantine 10’s of millions of people may help to slow the progress of the disease but may not be enough to stop the virus spreading.
Surgical masks to slow the spread?
One of the defining images of large respiratory disease outbreaks is people wearing surgical masks in the street, and this one is no different, most notably in China where they are also worn to protect against pollution. Many other cities in Asia are already reporting masks flying from the shelves, leading to shortages in the shops. But do these masks offer any protection for the wearer? The coronavirus is spread by droplets in the air produced when an infected individual coughs or sneezes, but it is also spread by touching a contaminated surface and then touching the mouth, nose, or eyes. This means that it is more likely for a person to become infected if they in close continuous contact with someone who is infected rather than a casual interaction on the street. In reality, the thin material in masks does little to stop respiratory viruses spreading, and masks have to be worn correctly, changed frequently and disposed of safely in order to work properly. There is however some limited evidence that suggests masks can help prevent hand-to-mouth transmissions.
Treatment and prevention
As this is a viral disease, antibiotics are not an effective treatment, and standard anti-viral drugs used against influenza will not work. So far, recovery has been very dependent on the strength of patients’ immune systems, and many of those who died are known to have suffered from poor health. Unlike influenza, there is no currently available vaccine, which means it is more difficult to protect vulnerable members of the population. How long will it take to develop an effective vaccine? The US NIH has suggested that a vaccine might be available for testing in humans in about 3 months, which represents an unprecedented speed of development. This has been enabled by technology for rapid genetic analysis of the virus, and prompt action by governments to begin a vaccine development programme.
So what can we do to avoid infection?
To minimize the effects of any respiratory illness, from the common cold to 2019-nCoV, doctors recommend the following precautions:
- Wash your hands regularly with soap and water for at least 20 seconds, or use an alcohol-based hand sanitiser.
- Avoid touching your eyes, nose, and mouth with unwashed hands.
- Try to avoid close contact with people who are sick, and stay home when you are sick.
Much like SARS in 2003 and MERS in 2012, the current coronavirus outbreak has caught local and global health systems by surprise, but it remains to be seen what the final impact of the epidemic will be on the world’s population.
The current epidemic results from infection by a coronavirus, one of a family of viruses that infect the nose, sinuses, or upper throat. Infection causes illnesses that range from the common cold to pneumonia and severe acute respiratory syndrome (SARS). The virus is named after its characteristic shape, which under an electron microscope looks like a royal crown with bulbous protrusions around it.1
Most such viruses are not dangerous. However, in early January 2020 the WHO identified a previously unknown type: 2019 novel coronavirus (2019-nCoV), a new strain not previously seen in humans. The first human cases had in fact been identified in the Chinese city of Wuhan in December 2019, before the cause was known. Initial symptoms of the viral infection included a fever, cough and difficulty in breathing, but in more severe cases the infection led to pneumonia, kidney failure and death.
By mid-January there were over 300 confirmed cases in China and a death count that was in the single digits but rising steadily. Many of those initially infected either worked or shopped in a large market in central Wuhan, which also sold live and newly slaughtered animals, leading to the assumption that the virus had jumped species, a not uncommon phenomenon. Interestingly, a genetically similar viral strain had been identified in a local breed of bats a few years’ previously, suggesting that the virus has jumped at least two species.
Spread of the virus
It is now clear that the virus is capable of person-to-person spreading. Scientists at Imperial College recently estimated that about 100,000 people around the world may already be infected with the new coronavirus and that each infected patient can infect on average 2.6 others – about the same rate as in annual influenza outbreaks. Worryingly there is concern that the coronavirus can be passed on during the disease’s incubation period, which means that someone who is ill but not yet displaying any symptoms could transmit the infection. A current count of more than 100 deaths out of 6,000 reported cases implies a 1.7% mortality rate, compared with seasonal influenza (which causes about 400,000 deaths each year globally) with a mortality rate well below 1%.
First lines of defence
One of the first lines of defence is monitoring airline passengers flying in from areas where the virus is active, often using thermal imaging cameras to detect fever, in an attempt to identify people who have symptoms. The problem is that only those who are already ill will be picked up, although it is thought that the incubation period (how long it takes for symptoms to appear after catching the infection) is days, rather than weeks. More draconian measures such as those instigated by China to effectively quarantine 10’s of millions of people may help to slow the progress of the disease but may not be enough to stop the virus spreading.
Surgical masks to slow the spread?
One of the defining images of large respiratory disease outbreaks is people wearing surgical masks in the street, and this one is no different, most notably in China where they are also worn to protect against pollution. Many other cities in Asia are already reporting masks flying from the shelves, leading to shortages in the shops. But do these masks offer any protection for the wearer? The coronavirus is spread by droplets in the air produced when an infected individual coughs or sneezes, but it is also spread by touching a contaminated surface and then touching the mouth, nose, or eyes. This means that it is more likely for a person to become infected if they in close continuous contact with someone who is infected rather than a casual interaction on the street. In reality, the thin material in masks does little to stop respiratory viruses spreading, and masks have to be worn correctly, changed frequently and disposed of safely in order to work properly. There is however some limited evidence that suggests masks can help prevent hand-to-mouth transmissions.
Treatment and prevention
As this is a viral disease, antibiotics are not an effective treatment, and standard anti-viral drugs used against influenza will not work. So far, recovery has been very dependent on the strength of patients’ immune systems, and many of those who died are known to have suffered from poor health. Unlike influenza, there is no currently available vaccine, which means it is more difficult to protect vulnerable members of the population. How long will it take to develop an effective vaccine? The US NIH has suggested that a vaccine might be available for testing in humans in about 3 months, which represents an unprecedented speed of development. This has been enabled by technology for rapid genetic analysis of the virus, and prompt action by governments to begin a vaccine development programme.
So what can we do to avoid infection?
To minimize the effects of any respiratory illness, from the common cold to 2019-nCoV, doctors recommend the following precautions:
- Wash your hands regularly with soap and water for at least 20 seconds, or use an alcohol-based hand sanitiser.
- Avoid touching your eyes, nose, and mouth with unwashed hands.
- Try to avoid close contact with people who are sick, and stay home when you are sick.
Much like SARS in 2003 and MERS in 2012, the current coronavirus outbreak has caught local and global health systems by surprise, but it remains to be seen what the final impact of the epidemic will be on the world’s population.
