Recent reports appear to suggest Lyme disease is far more common than initially suspected, with an unprecedented rise in the number of people afflicted with the tick-borne disease. The Centers for Disease Control and Prevention (CDC) have released recent estimates of the number of people affected, annually, which is considered to be around 300,000.
This statistic comes as a surprise. Most years, this figure remains much lower, with a typical incidence of between 20,000 to 30,000, which is at least 10 times lower than the CDC’s latest figure. However, the CDC considered previous estimates to be a gross under-representation, due to medical practitioners failing to report all cases.
Lyme disease is caused by a bacterium (Borrelia burgdorferi), transmitted through infected ticks. The blacklegged tick and western blacklegged ticks are particularly common, and are found across vast stretches of America. An immature form of the tick, called a nymph, typically becomes infected by the bacterium. This 2mm long creature then finds its way onto other animals, including human beings, where it takes a blood meal. Once the infected nymph begins feeding, within a couple of days, the bacteria is transmitted from the tick vector to its new host.
Ordinarily, fully grown ticks are unable to transfer the disease, since they are readily detected. As can be seen, the nymph are extremely small, allowing them to remain unnoticed in the hairy regions of the scalp, groin and armpits. Both mature and immature ticks secrete substances to keep them firmly rooted to the host’s skin, whilst an anesthetic numbs the area, which also helps the parasite evade detection.
But how could this pathology affect you, once bitten? Symptoms of Lyme disease are dependent upon the stage of infection, which typically worsen as the disease progresses. During the early stages of disease (up to a month, post-bite), the symptoms are as follows:
- Erythema migrans: a red rash, which continues to expand in size (up to 12 inches in diameter) and may form a bull’s-eye pattern
- Flu-like symptoms, including fever, headache, swelling of the lymph nodes
- Muscle and joint pain
Following this precursor stage, a slew of additional symptoms become apparent, including loss of muscle tone in the face (Bell’s palsy), meningitis, shooting pains and additional rashes. If left untreated, the condition gradually deteriorates, causing neurological manifestations and arthritis.
According to CBS News, the new figure’s calculation was based upon the information supplied by seven national laboratories, alongside data collected from insurance companies, and surveys completed by the general public.
Recent research does not suggest the disease is more wide-spread, however. Instead, it seems likely that the true incidence of Lyme disease was down-played, due to poor reporting practices.
According to the latest CDC press release, concerning this apparent rise in Lyme disease, the director of the CDC’s Division of Vector-Borne Diseases, Lyle R. Peterson, offers advice on how to avoid community-wide dissemination of the infection:
“We know people can prevent tick bites through steps like using repellents and tick checks. Although these measures are effective, they aren’t fail-proof and people don’t always use them… We need to move to a broader approach to tick reduction, involving entire communities, to combat this public health problem.”
From an individual perspective, people are advised to wear repellent, regularly check for ticks (utilising a fine-tooth comb) and shower soon after having been outside. It is also suggested that people who frequently wade through long grass and shrubbery wear baggy garments, to conceal at-risk parts of the body and provide at least partial protection.
Although Lyme disease may not be technically on the rise, these new figures are certainly alarming. Lyme disease could affect more people than experts ever imagined, and larger, community-wide efforts are now required to disrupt the life-cycle.
By: James Fenner