Monkeypox: How is it different from chickenpox?

Although the two diseases share many symptoms, there are several key differences

As the number of cases of monkeypox in the UK climbs to 302, concern continues to mount over the spread of the disease.

Many of the symptoms of the illness appear initially similar to chickenpox. However, there are several key differences between the two.

First, the diseases are caused by different viruses. Monkeypox is an orthopoxvirus, while chickenpox is caused by the varicella-zoster virus, which also causes shingles.

Both virus can spread through close contact through respiratory droplets and direct contact with skin lesions and recently contaminated objects.

While chickenpox is a common, highly contageous disease, monkeypox is rarer and spreads less easily.

Monkeypox is usually a mild illness with initial symptoms including fever, headache, muscle aches, backache, chills and exhaustion.

While many of these symptoms also appear in people infected with chickenpox, swollen lympnodes are a distinctive feature of monkeypox, which are not present in chickenpox.

The incubation period for monkeypox can be seven-to-14 days, while symptoms of chickenpox can take up to 16 days to appear, according to the US Centre for Diseases Control (CDC).

Following monkeypox infection, a rash, initially similar to a chickenpox, usually occurs within one to three days of a fever. The rash goes through several difference stages first developing into papules and fluid filled pustules before forming a scab and falling off.

However, a chickenpox rash forms in a different way to monkeypox. Spots do not develop uninformally in a chickpox rash, appearing at different at different times. Monkeypox lesions, however, appear and develop at the same time.

Monkeypox symptoms usually last between two to four weeks. Some strains can cause severe disease, with recent fatality recorded at 3 to 6 per cent, according to the World Health Organisation (WHO). Chickenpox symptoms can last up two weeks but usually subside in 7 days.

The UK government has released new guidance advising people with the virus, and those who have had direct exposure to a person infected with monkeypox, to isolate for three weeks.

People in this group are also being told not to travel and are advised to avoid contact with immunosuppressed people, pregnant women and children under 12.