Pop megastar Justin Bieber stunned fans with an Instagram post revealing that he has been diagnosed with Lyme disease.
Rumours had been circulating as to why Bieber appeared to be looking unwell, with some suggesting he had developed a drug problem.
But the star claims he is actually suffering from Lyme disease, a condition spread by tick bites, which is hard to diagnose and affects people differently.
His Instagram post read:
"While a lot of people kept saying justin Bieber looks like shit, on meth etc. they failed to realize I've been recently diagnosed with Lyme disease, not only that but had a serious case of chronic mono which affected my, skin, brain function, energy, and overall health.
"These things will be explained further in a docu series I'm putting on YouTube shortly.. you can learn all that I've been battling and OVERCOMING!! It's been a rough couple years but getting the right treatment that will help treat this so far incurable disease and I will be back and better than ever NO CAP"
The Scottish Highlands is one of the most tick-infested parts of the UK, making Lyme disease a particular concern there - here's everything you need to know about illness and how to avoid it.
What is Lyme disease?
Lyme disease, or Lyme borreliosis, is an infectious disease caused by a kind of bacteria called Borrelia.
This bacterium is carried by ticks and the disease is usually spread through tick bites.
What are the symptoms?
In many cases, the tell-tale sign of Lyme disease is an area of redness shaped like a bulls-eye appearing around the bite a week or so after it occurs. About 70-80% of people will experience this rash, although it may not be itchy or sore.
Many people also experience headaches, tiredness and fever soon after they have been infected. If it is not treated, it can then lead to facial paralysis, joint paints, severe headaches and heart palpitations.
The strangest thing about Lyme disease is that, while most people recover completely once the disease is treated, some experience repeated episodes of their symptoms for years afterwards. No-one knows why this is the case.
Even when it is properly treated, many patients (between 10 and 20% of those who contract the disease) suffer from memory problems, joint issues and tiredness for at least six months.
How is it diagnosed?
Lyme disease is also quite a difficult condition to diagnose because blood tests often come up negative during its early stages and many test are thought to be unreliable. Lyme disease is therefore more often diagnosed based on symptoms, while taking into account any recent exposure to ticks.
Things are made especially difficult by the fact that most people are completely unaware of having been bitten by a tick in the first place, and some do not experience the giveaway red bulls-eye.
The symptoms of Lyme disease can then take weeks to reveal themselves.
This difficulty in diagnosis has led to a lot of confusion, with Lyme disease often being mixed up with chronic fatigue system, according to some experts.
How common is it?
With over 300,000 reported cases each year in the US and a further 65,000 in Europe, Lyme Disease is the most common disease spread by ticks to be found in the Northern Hemisphere.
There were around 1700 confirmed cases in the UK in 2017, although this may not indicate the full number given how tricky the condition can be to diagnose. Some believe that, given how common it is in Europe, this estimate must be low.
As much as 13% of the UK’s tick population are believed to be infected with Lyme disease.
Infections occur mostly in the spring or summer time, with the New Forest in Southern England and the Scottish Highlands the UK’s two biggest tick hotspots.
How is it treated?
In the first place, Lyme disease can be prevented simply by taking measures to avoid getting bitten – using bug repellent to keep ticks away, pesticides to kill them and wearing clothing which keeps the skin covered.
After spending time in a likely tick habitat (anywhere with long grass), it is also advisable to check skin and clothing for ticks, removing any that have latched on using a pair of tweezers. A hot shower will also help to remove any that have gone undiscovered.
It is also worth remembering that, even if you are bitten by a tick, the odds of contracting the disease are extremely low.
If the disease is contracted, treatment will usually consist of a course of antibiotics, usually lasting two or three weeks.
However, those whose symptoms persist have mostly found that long-term antibiotic treatments are not effective.