With all the furore about monkeypox recently, I have gotten confused over all the pox diseases. First of all, what is pox?
A pox disease simply means any sort of viral disease characterised by pustules or eruptions i.e. pus-filled bumps on your skin.
In medieval times, the term pox was synonymous with syphilis, as it was rampant then. (“You’ve got the pox!” says a medieval doctor to a medieval sailor.)
There are plenty of viruses that can cause pox-like diseases in both humans and animals.
What sort of viruses cause pox?
Some of the more famous ones are:
- variola virus: smallpox
- vaccinia virus: cowpox, which was used to make the first vaccine to eradicate smallpox
- molluscum contagiosum: a benign, mild skin disease that resolves slowly which has small, raised lesions with a dimple or pit in the centre. May be be spread though sharing towels at a public swimming pool area or a sauna.
- Chickenpox
- Smallpox
- Monkeypox.
Let’s talk about monkeypox. Does it come from monkeys?
The natural hosts of the monkeypox virus are many types of animals, not just monkeys. They include rope squirrels, tree squirrels, Gambian pouched rats, dormice and primates – which include monkeys and apes.
The monkeypox virus itself is a DNA virus that belongs to one of the poxvirus families.
Did monkey pox originate in Africa?
It is likely. It was identified in humans in 1970 in the Democratic Republic of the Congo.
Everyone thought smallpox had been eradicated, and then, suddenly, a baby manifested a pox-like disease. It began to spread in the Congo basin and West Africa.
There have been many outbreaks since, but mostly contained in Africa. Then in 2003, the first monkeypox outbreak outside Africa was documented in the United States.
It was associated with contact to infected pet prairie dogs, which had been housed with Gambian pouched rats and dormice that had been imported from Ghana.
The 2003 outbreak led to over 70 cases of monkeypox in the US alone. Then in 2018, monkeypox was found in travellers from Nigeria to Israel, and the United Kingdom. Between 2019 and 2021, it was also found in Singapore and the US.
How will I get monkeypox?
It can jump from an animal to human first via blood, body fluids or fluid from the lesion itself. This is called a zoonotic transmission.
Then it can spread from human to human via respiratory secretions, skin lesions or even contaminated objects like used forks and towels.
So how do I know I have monkeypox as opposed to chickenpox or smallpox?
You are not likely to have smallpox as it has been largely eradicated around the world.
It can be very difficult to tell whether you have monkeypox or chickenpox since the lesions look the same. Only a diagnostic test will be able to tell.
Monkeypox is caused by the monkeypox virus, a member of the orthopoxvirus family.
Chickenpox is caused by varicella zoster virus, and smallpox by variola, which is also a member of the monkeypox family.
For monkeypox, the fever occurs one to five days before the pox rash appears.
For chickenpox, the fever comes quite swiftly, a mere one to two days before the rash.
For smallpox, it is two to four days.
During the fever period, you can have headache, back pain, muscle ache and fatigue which are characteristic of most viral diseases.
Do the rashes between monkeypox and chickenpox appear on the same body parts?
For monkeypox, the rash often starts on your face, then spreads to other body parts, such as your palms and soles. It can also affect your lips, genitals and eyes.
The rash starts off as a red lesion, called a macule. Then it gets raised and firm, which is called a papule. (This is termed as a maculopapular rash, and both macules and papules can appear at the same time.)
Then later, they become vesicles, which are lesions filled with clear fluid.
After that, the vesicles become pustules, which are filled with yellowish cloudy fluid. These eventually form a scab, which then falls off.
For chickenpox, you first get the itchy, blister-like rashes on your chest, back and face. Then it spreads to your entire body. Chickenpox never appears on your palms and soles.
Unlike chickenpox or smallpox, monkeypox can give you swollen lymph nodes.
Monkeypox typically is mild and can last between two to four weeks. It is fatal only in 3% to 6% of cases, and mostly in children. This is unlike smallpox, which used to be fatal in one third of cases.
Dr YLM graduated as a medical doctor, and has been writing for many years on various subjects such as medicine, health, computers and entertainment. For further information, email starhealth@thestar.com.my. The information provided is for educational and communication purposes only, and it should not be construed as personal medical advice. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.