Coronavirus and the disease it causes, Covid-19, have dominated the headlines. Yet the range of expectations and predictions of its impacts have been so wide as to make clear understanding almost impossible. This is perhaps inevitable when we grapple with a fast-moving and previously unknown illness. What is clear, is that as knowledge grows it has become evident that this has the potential to be one of the most fatal epidemics to have hit the world for a century, and it is rapidly increasing in prevalence in the UK.
I work as a doctor in an intensive care unit (ICU). It is a speciality (like anaesthesia its parent speciality) which most of the public have little understanding of unless they have required our services. What is in no doubt is that ICU sits at the centre of all that is necessary for keeping alive what may be a very large number of patients who will develop severe Covid-19.
ICU treats patients whose lives are at risk or whose organs have failed. Severe Covid-19 leads mostly to lung failure but also causes kidney and cardiovascular (heart and blood vessel) failure. All these are rapidly fatal without intense and prompt treatments only available in ICU. In simple terms, treatments include a ventilator taking over the patient’s breathing while the patient is anaesthetised (placed in an induced coma), a dialysis machine cleaning the blood and drugs or machines supporting the heart and blood pressure. The reality of care is, of course, considerably more complex and highly intensive.
So let’s look at some statistics: it is likely that more than 30% of the whole UK population will get Covid-19 – it may be as high as 60% in some estimates. Most will have no or mild illness but maybe one in seven will need hospital admission. Of patients in hospital up to one in five may need ICU care – that would be an unprecedented number of people admitted to ICU. As many as one in 50 of patients known to have Covid-19 may die from it.
What is Covid-19 - the illness that started in Wuhan?
It is caused by a member of the coronavirus family that has never been encountered before. Like other coronaviruses, it has come from animals. Many of those initially infected either worked or frequently shopped in the Huanan seafood wholesale market in the centre of the Chinese city.
Have there been other coronaviruses?
Severe acute respiratory syndrome (Sars) and Middle Eastern respiratory syndrome (Mers) are both caused by coronaviruses that came from animals. In 2002, Sars spread virtually unchecked to 37 countries, causing global panic, infecting more than 8,000 people and killing more than 750. Mers appears to be less easily passed from human to human, but has greater lethality, killing 35% of about 2,500 people who have been infected.
What are the symptoms caused by the new coronavirus?
The virus can cause pneumonia. Those who have fallen ill are reported to suffer coughs, fever and breathing difficulties. In severe cases there can be organ failure. As this is viral pneumonia, antibiotics are of no use. The antiviral drugs we have against flu will not work. Recovery depends on the strength of the immune system. Many of those who have died were already in poor health.
Should I go to the doctor if I have a cough?
UK Chief Medical Officers are advising anyone who has travelled to the UK from mainland China, Thailand, Japan, Republic of Korea, Hong Kong, Taiwan, Singapore, Malaysia or Macau in the last 14 days and who is experiencing a cough or fever or shortness of breath to stay indoors and call NHS 111, even if symptoms are mild.
Is the virus being transmitted from one person to another?
China’s national health commission has confirmed human-to-human transmission, and there have been such transmissions elsewhere.
How many people have been affected?
As of 4 March, the global death toll was 3,190, while more than 93,000 people have been infected in more than 80 countries.
The death toll has passed 3,000 in China, where there have been over 80,000 cases. South Korea, the nation worst hit by the outbreak outside China, has had 5,328 cases. More than 44,000 people in China have recovered from Covid-19.
There have been 87 recorded cases and no fatalities to date in the UK. There are 53 confirmed cases in Australia, with two deaths.
Why is this worse than normal influenza, and how worried are the experts?
We don’t yet know how dangerous the new coronavirus is, and we won’t know until more data comes in. The mortality rate is around 2% at the centre of the outbreak, Hubei province, and less than that elsewhere. For comparison, seasonal flu typically has a mortality rate below 1% and is thought to cause about 400,000 deaths each year globally. Sars had a death rate of more than 10%.
Another key unknown is how contagious the coronavirus is. A crucial difference is that unlike flu, there is no vaccine for the new coronavirus, which means it is more difficult for vulnerable members of the population – elderly people or those with existing respiratory or immune problems – to protect themselves. Hand-washing and avoiding other people if you feel unwell are important. One sensible step is to get the flu vaccine, which will reduce the burden on health services if the outbreak turns into a wider epidemic.
Is the outbreak a pandemic?
A pandemic, in WHO terms, is “the worldwide spread of a disease”. Coronavirus cases have been confirmed outside China, but by no means in all 195 countries on the WHO’s list. It is also not spreading within those countries at the moment, except in a very few cases. By far the majority of cases are travellers who picked up the virus in China.
Should we panic?
No. The spread of the virus outside China is worrying but not an unexpected development. The WHO has declared the outbreak to be a public health emergency of international concern. The key issues are how transmissible this new coronavirus is between people, and what proportion become severely ill and end up in hospital. Often viruses that spread easily tend to have a milder impact. Generally, the coronavirus appears to be hitting older people hardest, with few cases in children.
ICU is a precious and scarce resource in terms of beds, staff and equipment. This is especially so in the UK. In 2012 the UK had about 4,100 critical care beds including ICU beds and “high dependency” beds which are a step down from full ICU care. Compared with other European countries the UK ranked 23rd of 31 in terms of ICU beds per head of population and 29th of 31 for all hospital beds. Germany has approximately four times as many ICU beds per capita as the UK and the USA perhaps 10-fold as many. Data from 2017 suggest little change. Most UK ICUs therefore run at or above 90% occupancy and often can only admit new patients only by discharging others – even when workload is normal. Covid-19 will increase pressures not only because of weight of numbers but because intermediate treatments for pneumonia and lung failure are “aerosol-generating” (ie they risk spreading the disease) so cannot be used and early recourse to ICU is required.
Increased ICU demands equate to each ICU bed being needed for approximately 100 more patients than on average in the epidemic period – at least 10 times the normal throughput and equivalent to needing at least another 10 ICUs in the hospital during the epidemic. Of course, this demand will be in addition to, rather than instead of, normal workload as the illnesses that usually require ICU admission will not go away during the epidemic. In Wuhan, ICU capacity was increased by over 1,000 beds in two weeks by building a new hospital, but this is not possible in the UK.
Managing an ICU patient with Covid-19 is more complex than normal ICU care. Patients must be individually isolated. All staff must wear “personal protective equipment” (PPE), which consists of, as a minimum, a tight-fitting face mask, an extra gown, gloves, goggles and visor. PPE must be put on and taken off before and after patient contact and checked by a “buddy” colleague. Despite this scrupulous process in China two in every five early infections were acquired in hospital and two-thirds of these were healthcare workers, a significant number of whom then died. These demands slow down care, increase the number of staff needed and expose staff (and perhaps their families) to significant risk.
Patients in ICU have constant one-to-one nursing. Medical interventions are frequent, invasive and performed at extremely close proximity. Contact with body fluids is inevitable and common. But it is not only nurses and doctors who are at risk. Hospital cleaners will be required to be on hand at all times and rigorous cleaning is required between patients and after many procedures. Physiotherapists, dietitians, laboratory technicians and other medical specialists involved in care are also at risk. Keeping staff safe has implications beyond their welfare: skilled staff are a limited resource and if sickness rates are even moderate there will be major gaps in service.
The challenge from Covid-19 to ICU services in the UK is enormous and pressing. Throughout the UK, ICUs are preparing exceptional plans and training all staff to manage these patients with skill and safety, for the patient and themselves. Hospitals are acting to expand ICU care outside its existing footprint and double or even treble ICU capacity, most likely by taking over operating theatres. This expansion will involve engaging anaesthetists and others to provide ICU medical care and nurses from elsewhere in the hospital to work as ICU staff. To facilitate this, much or all routine surgery will need to stop. Many patients with Covid-19 will also be hospitalised outside ICU and care of these patients and those in ICU will have major consequences for caring for other patients who do not have Covid-19.
Whether these extreme precautions will be needed is unknown. If they are, whether even these measures will be sufficient is also unknown. We will find out over the next few weeks and months. In the meantime, preparations need to be accelerated and coordinated and we need to be honest and transparent about the potential impact of a Wuhan-type epidemic here in the UK, which no doubt will pose a major challenge to everyone working in the NHS.
• Tim Cook is a doctor in an NHS intensive care unit
