According to a major review of available research published Tuesday, more than 14 percent of the world’s population has Lyme disease, a common tick-borne disease.
A study in the journal BMJ Global Health found that Central Europe has a 20 percent infection rate and men over 50 years of age are more at risk in rural areas.
The condition is rarely fatal, but people who get bitten by an infected tick usually get rashes and experience flu-like symptoms, including muscle and joint pain, headache, nausea, and vomiting.
To find out how common Lyme disease is worldwide, researchers gathered data from 89 studies.
Borrelia burgdorferi (BB), a disease-causing bacterium, was found in the blood of 14.5 percent of the approximately 160,000 total participants.
“This is the most comprehensive and up-to-date systematic review worldwide,” the researchers said.
After Central Europe, the regions with the highest antibody rates were East Asia 15.9 percent, Western Europe 13.5 percent and Eastern Europe 10.4 percent.
The Caribbean, meanwhile, has the lowest rate, only two percent.
Previous research has shown that the spread of tick-borne diseases has doubled in the last 12 years.
Climate change, migration of animals, loss of habitat and “frequent pets contact” are the reasons for the rise of long, dry summers, the study said.
The study found that farmers and workers who regularly interact with host animals, such as dogs and sheep, are at higher risk of being bitten by an infected tick.
It warns that data may be skewed in areas where Lyme disease is endemic, as healthcare workers are more likely to conduct regular antibody tests where they are less common.
Research using an analytical technique called Western blotting is highly reliable and its use could “significantly improve the accuracy” of future studies, the study said.