As Lyme disease finally enters the public consciousness after years of being a vastly misunderstood fringe condition, new questions and concerns are arising from patients and doctors alike. There’s still a vast amount of misinformation out there about the disease; this is compounded by the fact that many doctors across the world are not fully Lyme-literate, and in most cases, a specialist needs to be called in to fully determine a potential case of Lyme. By and large, the acute form of Lyme disease is widely accepted by medical professionals – but this is the easy form to spot, as it usually comes accompanied by a distinctive rash. The chronic form is vastly more difficult to diagnose and treat. After a long, hard treatment road, many patients ask the question: can I catch Lyme disease more than once?
This is a more complex question than it might first appear. The short answer is no, but the long answer is yes. Before we break it down, it’s important to understand exactly how Lyme disease is contracted. Most people correctly associate the disease with ticks, but it’s only a specific type of ticks that carry the offending bacteria strain. They are the deer tick (or black-legged tick) in North America, and the sheep tick in Europe. Not all ticks are infected with Lyme bacteria (Borrelia burgdorferi), but it’s estimated that one in three ticks are, so the chances of infection are quite high. Also, while it’s been suggested in the past that the tick must be attached to its host for over 24 hours to allow for risk of transmission, recent studies (like this one conducted by the Institut Pasteur in France) conclude that transmission can routinely occur within 24 hours.
If you live or walk around heavily tick-populated areas, the risk of catching Lyme disease is actually quite high. The condition can be easy to treat if caught in the acute stages; the symptoms present as flu-like, and are often eradicated by a round or two of antibiotics. However, if the infection persists and mutates to its chronic stage, it can be much harder to detect and treat. The symptoms are much more informed by the immune system response at this stage, and often include muscle and joint pain, irrepressible fatigue, headaches and neurological symptoms. Treatment is long and hard, and once you get out the other side, it can be tempting to assume you are immune from any further infections.
However, Lyme disease doesn’t operate like this. The short answer to the question ‘can I catch Lyme more than once?’ is undoubtedly ‘yes’. All it requires is to be bitten by another tick carrying the disease. The same process will repeat, with the acute form presenting a rash and flu-like symptoms, before the slow degeneration into the debilitating chronic phase. After battling Lyme once, a patient might be much more wary of tick-infested areas and tick bites in general; this higher alertness may well reduce their chances of re-contracting. But logically and medically, it’s entirely possible to catch Lyme more than once.
However, like most things relating to Lyme, this question is more complex than it first appears. A 2012 study published in the New England Journal of Medicine reported on a number of patients who had been infected a number of times with Lyme. The point of this experiment was to ascertain whether repeat infections were a result of new strains, or simply relapses of the original infection (a common occurrence with chronic Lyme). It was concluded that all but one of the 17 patients surveyed were infected by new strains, not one recurrent one.
Building on this study, researchers conducted a new experiment in 2014, using the original data, this time to see if there was any kind of immunity derived from Lyme infection. The study was subsequently published in the Infection and Immunity journal, and concluded that statistically, it would be nearly impossible to arrive at the results of the first experiment if some kind of immunity was not present. For the second stage of the study, data from over 200 participants confirmed Lyme disease was used to parameterise the model to provide a wider range. The final conclusion from the simulation was that immunity to a specific strain of Lyme lasts in the region of six to nine years.
While this may sound encouraging, it’s certainly no cause for celebration. There are at least 16 strains of Lyme thought to infect humans in the United States, making it incredibly likely that you can catch the disease again if bitten by another tick. On top of that, Lyme experts such as those in BCA-clinic in Augsburg, Germany, are all too aware of the dangers of co-infections that usually accompany Lyme. These malicious co-infections can sometimes be as dangerous and debilitating as Lyme itself, and are also carried by ticks. As ever, it’s best to assume nothing when it comes to Lyme disease; we still know comparatively little about the disorder, and though we are keen to learn, it will still be a few years before we fully get to grips with the intricacies of the condition.