Up to one in seven people worldwide could have Lyme disease, new estimates suggest.
For decades, researchers have not known exactly how widespread the tick-borne disease was.
The new findings could open up ways to combat the bacterial infection, which can cause years of symptoms such as headaches, muscle and joint pain and fatigue in those affected.
Singer Justin Bieber and model Bella Hadid are just two celebrities who have spoken out about their plight with Lyme.
Academics from China examined blood sample data from studies involving 150,000 people.
The results showed that 14.5 percent had antibodies indicative of Lyme disease.
Canadian pop singer Justin Bieber (left) has spoken out about suffering from Lyme disease, while American model Bella Hadid (right) has revealed she has been suffering from an irregular heartbeat, joint pain and breathing difficulties as a result of the disease
Lyme disease is a bacterial infection transmitted by a tick bite. It causes a round rash and can trigger flu-like symptoms, but usually gets better within weeks or months with antibiotics. Pictured: tick population
However, in Central Europe, an area that typically includes Germany and Poland, rates were just over 20 percent.
Researchers said a “more accurate” figure on the global prevalence of Lyme disease would “identify risk factors.”
WHAT IS LYME DISEASE?
Lyme disease is a bacterial infection transmitted to humans by infected ticks.
It causes symptoms such as a circular or oval-shaped rash around a tick bite, which usually appears within four weeks of the bite but can take up to three months to show.
Some people also get flu-like symptoms in the days after the bite, including high fever, headache, muscle and joint pain, and loss of energy.
And some of those who suffer from Lyme disease continue to have symptoms such as fatigue, pain and loss of energy that can last for years.
It is not clear why some experience persistent symptoms and there is no agreed treatment for the disease.
Not all ticks carry the bacteria that causes Lyme disease, but infected ticks can be found across the UK.
High risk areas include grassy and wooded areas of northern and southern England and the Scottish Highlands.
People are advised to remove ticks safely and as soon as possible with tweezers.
This, they said, “could feed into the development of public health response measures and control programs.”
To date, the most accurate figures have put around 900 Britons and 30,000 Americans downed each year. However, these were widely considered to be too low.
Ticks are second only to mosquitoes in terms of the number of harmful microbes they carry.
Some harbor Borrelia burgdorferi sensu lato, the bacterium responsible for Lyme disease.
The infection triggers a circular, oval-shaped rash around a tick bite that can appear up to three months after the bite.
The bacteria can also spread to other tissues and organs, potentially affecting the nervous system, joints, heart, and skin for years.
But it’s not clear why some suffer from persistent symptoms – and there’s no agreed treatment for the disease.
Researchers from Kunming Medical University in China looked at 89 Lyme disease studies involving 158,287 people conducted between 1984 and 2021.
Each study looked at Lyme disease rates using blood test results because it triggers antibodies in the same way as Covid does.
This means that a blood test can confirm whether a person is currently or has been infected.
The team wrote in BMJ Global Health that its findings are the “most comprehensive and up-to-date systematic review of the worldwide prevalence” of Lyme disease.
A fifth of people in Central Europe tested positive – the highest rate – followed by East Asia (15.9 percent) and Western Europe (13.5 percent).
For comparison, rates were lowest in the Caribbean (2 percent), South Asia (3 percent), and Oceania (5.3 percent).
The researchers found that tick-borne diseases have doubled in the past 12 years. Such pathogens pose a “significant and growing public health problem” and are a “major cause of disease and death worldwide,” they said.
Ticks have spread worldwide in recent years and “greatly increase the risk of human exposure,” the study says.
This could be due to longer summers and warmer winters, animal migration, and more time outdoors.
A sub-analysis found that those over 50, males and people living in rural areas were most likely to develop Lyme disease.
Men were more likely to work in occupations where they are more exposed to ticks, such as B. Farmers, police officers and soldiers.
The team said it was “essential” to develop new treatments and prevention methods.
However, they found that a third of the studies used only one type of test to confirm Lyme disease infection.
These studies reported more cases than those that used a second test to confirm a case.
This may be because the bacteria behind Lyme are similar to other viruses such as Epstein-Barr.
And they said some of the studies were done in regions where Lyme disease is endemic and therefore had much higher rates.
So the figure of 14.5 percent could be “overestimated and not representative of the world’s population,” the researchers said.
A standard worldwide testing method would offer “great value” in confirming the prevalence of Lyme disease and information on which groups are most at risk, the team said.