NEW YORK: In 2022, doctors recorded the first confirmed case of tick-borne encephalitis virus acquired in the United Kingdom.A 50-year-old man was mountain biking in the North Yorkshire Moors, a national park in England known for its vast expanses of woodland and purple heather. At some point on his ride, at least one black-legged tick burrowed into his skin. Five days later, the mountain biker developed symptoms commonly associated with a viral infection - fatigue, muscle pain, fever.
Gábor Földvári, an expert at the Center for Ecological Research in Hungary, said the effects of climate change on TBE are unmistakable.Ticks can’t survive more than a couple of days in temperatures below zero, but they’re able to persevere in very warm conditions as long as there’s enough humidity in the environment. As Earth warms on average and winters become milder, ticks are becoming active earlier in the year.
According to the World Health Organization, there are between 10,000 and 12,000 cases of the disease in Europe and northern Asia each year. The total number of cases worldwide is likely an undercount, as case counts are unreliable in countries where the population has low awareness of the disease and local health departments are not required to report cases to the government.
Up to half of survivors of severe TBE have lingering neurological problems, such as sleeplessness and aggressiveness. Many infected people are asymptomatic or only develop mild symptoms, Dobler said, so the true caseload could be up to 10 times higher in some regions than reports estimate.