Is monkeypox like Covid? How viruses compare - from case numbers to how they spread, vaccines, and death rate

Monkeypox cases in the UK are continuing to rise, with guidance from the UK Health Security Agency (UKHSA) urging anyone who has had direct or household contact with a confirmed case to isolate for 21 days.

But could monkeypox evolve in the same way as Covid and turn into a global pandemic?

We spoke to health experts to find out how the virus could evolve - and if we should be worried.

‘When a virus breaks out like this, it is always a cause for concern’

Hussain Abdeh, clinical director and superintendent pharmacist at Medicine Direct, said monkeypox is “definitely not another Covid, so people needn’t fear us becoming locked down in our homes”.

He added: “Monkeypox is better understood than Covid was at the start of the pandemic.”

The first Covid cases in the UK were first identified in January 2020, and people who contracted the virus were asked to self isolate.

However, as Covid cases began spreading quickly across the country, on 16 March 2020 people were asked to work from home wherever possible and everyone was told to “avoid pubs, clubs, theatres and other such social venues”.

A week later, on 23 March 2020, the UK’s first lockdown began. So how does the trajectory of monkeypox compare so far?

The latest outbreak of monkeypox was first identified in the UK on 7 May, with the UK Health Security Agency (UKHSA) guidance recommending on 23 May that people who have had “unprotected direct contact or high-risk environmental contact” self-isolate for three weeks.

However, unlike the Covid lockdown and self-isolation requirement, the monkeypox isolation guidance is advisory and not mandatory.

There are currently 321 cases of monkeypox in the UK as of Friday 3 June, and although this is quite a small number for the UK, the daily cases are “an unusual and unprecedented high for this country”, according to Mr Abdeh. Monkeypox is typically found in parts of west or central Africa and cases are usually rare in the UK.

“When a virus breaks out like this, it is always a cause for concern, although not for panic,” he said.

“Monkeypox is outside of its usual home while in the UK, meaning it requires prolonged close contact between humans to keep thriving. Consequently, outbreaks of monkeypox are normally short-lived.”

Martin Michaelis, professor of molecular medicine at the University of Kent, echoed this, saying that if “nothing unforeseen happens”, then it “seems unlikely that monkeypox will cause an outbreak at the scale of Covid-19”.

The professor explained that monkeypox does not spread as easily as Covid, as you can easily be infected by a person with Covid if you are in the same room as them for a short while, even without direct contact.

However, people tend to need to be in much closer contact for monkeypox to be transmitted, with the virus spread by touching someone with the infection, using the same bedding or by them directly sneezing or coughing at you, noted Prof Michaelis.

The symptoms of monkeypox, including a rash and blisters, are also “much more obvious and unambiguous and cannot be easily confused with a common cold like Covid-19,” said Prof Michaelis.

He added: “Monkeypox is usually also only infectious in patients who display symptoms.

“Hence, there is not this level of asymptomatic spread by people who do not know that they are infectious, which we are used to from Covid-19.”

Possibility of mutation

One of the most worrying aspects of Covid is its ability to mutate and potentially become more serious than the original strain. Throughout the pandemic, we have seen various iterations of the virus - from the Delta strain to the milder Omicron variant. So what are the chances of Monkeypox doing the same, and potentially becoming a more serious illness?

Martin Michaelis, professor of molecular medicine at the University of Kent, said the monkeypox virus is a DNA virus, whose genome has been fairly stable in the past.

In comparison, SARS-CoV-2, the coronavirus that causes Covid-19, is an RNA virus which has a very high mutation rate and can evolve very quickly.

This means that the risk of mutations in monkeypox is “substantially lower” than for Covid, explained Prof Michaelis.

However, he added that mutations in monkeypox do still happen and even a few or just one mutation may change the features of a virus.

“This would be of particular concern if we had continued human-to-human spread, which would give the monkeypox virus an opportunity to adapt better to humans,” said Prof Michaelis.

This is echoed by Mr Abdeh, who said viruses are “constantly mutating”, which they need to do “in order to survive”.

Given that we have seen several different variants of Covid as a result of the virus evolving to combat vaccines, it is possible that monkeypox could also mutate, he explained.

However, since monkeypox is a “far better-understood virus” than Covid, with much research already in existence, it would be easier to treat as a result, said Mr Abdeh.

How deadly is monkeypox?

The latest World Health Organisation (WHO) fact sheet says historically the fatality rate for monkeypox has ranged from 0% to 11%, but in recent times has been around 3-6%.

However, the upper ranges may be in countries without good healthcare so it’s by no means a universal fatality rate.

Monkeypox is usually a mild illness that will get better on its own without treatment, but some people can develop more serious symptoms, so patients with monkeypox in the UK are cared for in specialist hospitals.

Treatment for monkeypox aims to relieve symptoms, with most people recovering in two to four weeks, Mr Abdeh said.

In comparison, estimates on Covid’s fatality rate have varied throughout the pandemic. Many studies estimated it to be between 0.5% and 1% during the first year, but the deadliness may have varied from country to country according to their wealth and healthcare infrastructure.

The fatality rate will also have improved over time as better treatments were developed.

Is there a vaccine for monkeypox?

While several vaccines were developed to prevent the spread of Covid, there is not currently a monkeypox vaccine in the UK - although the US does have one.

However, the UK Government recently bought stocks of the smallpox vaccine to be used against monkeypox.

Prof Michaelis said that due to the UK now having smallpox vaccines that provide “reasonable protection from monkeypox, even up to about four days after infection”, it should therefore be “feasible to break transmission chains by contact tracing and isolating and vaccinating contacts of monkeypox patients”.

He also added that older people who received the smallpox vaccine before the vaccination programmes were stopped in the 1970s or early 1980s should “still have some level of protection against monkeypox”.

According to the WHO, the clinical presentation of monkeypox resembles that of smallpox, as it is a related orthopoxvirus infection, but smallpox was eradicated worldwide in 1980.

Monkeypox symptoms are similar to those seen in the past in smallpox patients, but it is clinically less severe.

Lymphadenopathy, which is the swelling of the lymph nodes, is also a distinctive feature of monkeypox compared to other diseases that may initially appear similar, such as chickenpox.

Monkeypox and smallpox are both caused by members of the poxvirus family, but chickenpox is caused by the Varicella zoster virus and is not related to the poxviruses.

Monkeypox and children

Worryingly, Prof Michaelis said monkeypox could  present a greater risk to children than Covid-19, as children are “particularly vulnerable to this disease and have not been vaccinated against smallpox”.

However, researchers who have been looking into the current monkeypox outbreak, as well as past cases of the disease, have said it is rare in children.

Dr David Porter, paediatric infectious diseases consultant, Alder Hey Children’s NHS Foundation Trust, said: “As a parent with a child that might develop a rash, I don’t think parents should be worried about this being…monkeypox at this stage, because we’re seeing a very low number of cases.

“And in all the previous outbreaks that have occurred outside of Africa over the last few years, we’ve seen very rare numbers of cases in children, so it’s been predominantly in adults anyway.”

He added that if children have a rash and no contact history with someone who has had monkeypox, parents and carers should be reassured and follow what they normally do.

First case of monkeypox identified in Ireland

The first confirmed case of monkeypox has been identified in Ireland, the Health Service Executive (HSE) has said.

The infection was reported in the east of the country on Friday (27 May) night and the person affected was not kept in hospital.

A further suspected case is also being investigated and test results are being awaited, health officials said.

A public health risk assessment has been undertaken and those who have been in contact with the person are being advised on what to do in the event that they become ill.

A statement from HSE said: “The Health Protection Surveillance Centre was notified last night of a confirmed case of monkeypox in Ireland, in the east of the country.”

“This was not unexpected following the presence of monkeypox cases in the UK and many European countries,” it added.

“Public Health is following up those who had close contact with the person with monkeypox while they were infectious.

“In order to maintain patient confidentiality, no further information about this person will be provided.”

Almost 200 cases have been reported in more than 20 countries not usually known to have outbreaks of the virus, according to the World Health Organisation.

Should we be worried?

As the above experts have said, monkeypox is not likely to evolve in the same way as Covid and it’s highly unlikely the UK will experience a lockdown due to the virus.

However, with viruses having the potential to mutate and with monkeypox able to be passed and spread between humans and animals, it is a virus that will be closely monitored and it’s not clear yet what the outcome will be.