Lyme borreliosis and its co-infections

Lyme borreliosis, also known as Lyme disease, is the most common zoonotic infection in the world — that is, an illness transmitted from animals to humans — and the most widespread bacterial disease carried by ticks. Its causative agent is the bacterium Borrelia burgdorferi: a highly motile, spiral-shaped bacterium of the Borrelia genus, a spirochete approximately 15 micrometres long and 0.2 micrometres wide. It is often referred to as the “Teflon parasite” because its surface is covered by a special substance with very few surface antigens, making it difficult for the body’s antibodies to attach. Without treatment, it can hide in the body for years or even decades. In addition to its remarkable adaptability and strong defensive capacity, its persistence is also due to its vegetative forms known as gemmae.

Lyme borreliosis is caused by bacteria that enter the open skin wound created by a tick bite. The pathogens can survive and remain in the tick’s midgut for months or even years. Because a tick bite is painless, the blood-feeding may last for several days, allowing the infected blood to flow back into the wound and directly into the small blood vessels.

Lyme borreliosis can affect any organ months, years, or even decades after infection. The pathogen can travel anywhere in the body through the bloodstream and, under suitable conditions — when the immune resistance decreases — can trigger chronic inflammation. Spontaneous recovery has not been proven, but the disease can be effectively treated with medication.

According to current knowledge, the disease does not spread from person to person; it is transmitted from infected animals to humans through ticks. An exception is mother-to-child transmission, which can occur through the placenta and may result in infection of the fetus.

The early skin inflammation, which in itself can be considered diagnostic — the Lyme rash — is usually ring-shaped, resembling a target or a bull’s-eye: inflamed, apparently healthy, and healing skin areas may alternate. However, it can also appear differently, sometimes with a more purplish tone and not always in a circular pattern. In some cases, due to its large size, parts of it may overlap — for example, under the hair — making its shape difficult to determine. The Lyme rash expands day by day.

Despite the infection, the Lyme rash may not appear at all. The skin inflammation develops — or is noticed by the patient — in approximately one-third of all cases.

Lyme disease often causes chronic skin inflammation (atrophic skin degeneration or scarring), but it can also affect the nervous system (neuritis, primarily of the cranial nerves, meningitis, or encephalitis), the joints and muscles (especially large joints, but also small ones), and the heart (pericarditis, arrhythmia). In fact, it can affect any organ, as it is a systemic disease. Therefore, the disappearance of the Lyme rash does not mean that Lyme borreliosis has been cured!

Borrelia burgdorferi, the bacterium that causes Lyme disease, is sensitive to many medications and can be treated with several types of antibiotics available in Hungary. The specialist determines the specific strains (subtypes) of the bacterium and takes their differing antibiotic sensitivities into account when developing the treatment plan. Complete recovery depends on early detection of the disease, the use of effective, adequately dosed, and sufficiently long-lasting combined antibiotic therapy, as well as timely repetition of treatment if needed. According to current knowledge, there is no natural or herbal remedy that can effectively cure Lyme disease on its own.

Lyme borreliosis is the most common zoonosis — that is, a disease transmitted from animals to humans — both worldwide and throughout Hungary. According to our estimates, several hundred thousand, possibly up to one million people in Hungary may suffer from Lyme borreliosis. Recent statistics show that one in five people has already encountered the pathogen. In Europe, at least 650,000 to 850,000 new infections occur each year (some estimates suggest more than 2.5 million), while in Hungary the number can reach up to twenty thousand annually. Lyme disease is at least five times more common than AIDS and one and a half times more common than breast cancer. It is being diagnosed increasingly often, partly due to growing awareness of the disease, but also because ticks are expanding their territory as a result of climate change. Milder weather and the absence of hard frosts allow more ticks to survive the winter. Some studies even suggest that infected ticks have a selective advantage in surviving milder frosts.

A single tick bite can lead to the development of several infections. Not only Lyme disease but also other bacterial infections transmitted by ticks can spread through the bite. Co-infections associated with Lyme borreliosis and tick bites — such as Bartonella, Babesia, Anaplasma, Ehrlichia, Mycoplasma, and Chlamydia — can cause symptoms similar to those of Lyme disease. It is therefore crucial to determine through testing whether Lyme disease or one of its co-infections is present, so that the patient can receive the appropriate treatment.