Lyme disease cases have soared almost five-fold in 15 years because of global warming, according to new research. The potentially-fatal bacterial infection is transmitted by tiny spider-like blood-suckers. Campers and hikers are particularly prone.
An analysis found diagnoses rose 357 per cent in rural areas in the US between 2007 and 2021. In towns and cities they increased by around two thirds (65 per cent). Similar trends have been observed in the UK.
Longer summers and warmer winters are to blame, along with animal migration and increased time spent outdoors. Over-50s, men and those living in rural areas are most vulnerable. Infected ticks can be found across Britain.
New York-based FAIR Health said Lyme disease has become an "illness of increasing national concern." It used its database of over 36 billion privately billed healthcare claims in the US to carry out the study.
In the UK, high-risk areas include grassy and wooded areas in northern and southern England, as well as the Scottish Highlands. For decades, scientists have been clueless as to exactly how widespread the tick-borne illness really is.
The latest findings add to evidence that it is much more widespread than previously feared. If left untreated it can lead to serious symptoms affecting the joints, nervous system - and even the heart.
The charity's freely available 'infographic' reveals key differences in prevalence when comparing different regions. From 2016 to 2021, claims with Lyme disease diagnoses increased 60 percent in rural areas and 19 percent in urban areas - peaking nationally in June and July.
During summer months rural areas, on average, had a greater share of claim lines associated with Lyme disease. From November to April, however, claim lines diagnoses occurred more often in urban areas.
In 2017, the states with the greatest proportion of Lyme disease diagnoses were New Jersey, Connecticut, North Carolina, Rhode Island and Vermont. Lyme disease has been historically associated with the Northeast and upper Midwest of the US.
The emergence of North Carolina as the third highest hotspot suggested marked expansion. But by 2021 it had dropped from the list - with the top states top states New Jersey, Vermont, Maine, Rhode Island and Connecticut.
Lyme disease is treatable with antibiotics. Some patients later develop conditions with long-term symptoms, such as fatigue, muscle and joint pain and cognitive issues. They have been dubbed post-treatment Lyme disease syndrome - or chronic Lyme disease.
To identify later diagnoses, the researchers examined a statistically significant cohort of individuals in its private insurance claims database from 2017 to 2021. They compared the prevalence of certain diagnoses among Lyme patients to all patients in the cohort.
The analysis found diagnoses such as malaise and fatigue and soft-tissue-related issues were more common among Lyme patients. Across all age groups, patients with Lyme disease were generally more likely to have these apparently associated diagnoses than all patients in the cohort.
FAIR Health President Robin Gelburd said: "Lyme disease remains a growing public health concern. FAIR Health will continue to use its repository of claims data to provide actionable and relevant insights to healthcare stakeholders seeking to better understand the ongoing rise of Lyme disease cases."
It is the third study FAIR Health has conducted on Lyme disease, the first appearing in an infographic released in 2017 and the second in a white paper published in 2019. In June a study found up to one in 10 people in the US may have had Lyme disease - around 50 million or 9.4 percent of the population.
Globally up to 14.5 percent of people have had the disease - or one in seven - the researchers claimed. The bacterial infection causes a round rash and can trigger flu-like symptoms but usually gets better with antibiotics within weeks or months.
People are advised to remove ticks safely and as soon as possible using tweezers. It is not known how many die, although deaths are rare. Ticks are second only to mosquitos in terms of the number of harmful microbes they carry.
Some harbour Borrelia burgdorferi sensu lato, the bacteria which is responsible for Lyme disease. Signs of a long-term illness include severe headaches, facial paralysis and an irregular heartbeat.
