Lyme disease is a bacterial infection caused by the spirochete Borrelia burgdorferi, transmitted to humans through the bite of an infected blacklegged tick. The condition affects multiple systems, including the skin, joints, and nervous system. Individuals often wonder if symptoms like a cough or other respiratory issues can be a direct result of the infection. This article explores the connection between Borrelia infection and respiratory symptoms.
Is Coughing a Recognized Symptom of Lyme Disease?
A cough is not considered a primary or typical symptom of Borrelia burgdorferi infection. The bacterium primarily causes a systemic illness affecting connective tissues and the nervous system, not the respiratory tract. Early Lyme disease presents with flu-like symptoms, including fever, chills, fatigue, and body aches, but usually lacks the prominent respiratory features seen in a common cold or the flu.
The absence of a runny nose, sore throat, or persistent cough often helps clinicians distinguish early Lyme disease from a viral infection. While a dry cough is occasionally mentioned in rare case reports, it is not a recognized feature used for diagnosis. If a patient with confirmed or suspected Lyme disease reports a persistent cough, medical professionals typically investigate other potential causes.
Common Manifestations of Lyme Infection
Lyme infection progresses through distinct stages, beginning with the early localized phase days to weeks after a tick bite. The most recognized sign is the Erythema Migrans rash, an expanding area of redness appearing in 70% to 80% of infected individuals. This stage is often accompanied by non-specific flu-like symptoms, such as headache, fever, muscle aches, and swollen lymph nodes.
If untreated, the infection can progress to the early disseminated stage, where the bacteria spread throughout the body. Symptoms at this stage, weeks to months later, can include multiple Erythema Migrans lesions, severe headaches, and neurological issues like facial palsy.
The infection can also affect the heart, causing Lyme carditis, which may present as heart palpitations or an irregular heartbeat. Late-stage manifestations occur months to years after the initial exposure, frequently presenting as Lyme arthritis, involving severe joint pain and swelling, particularly in the knees.
The Role of Tick-Borne Co-infections
The most likely reason an individual with Lyme disease may experience a persistent cough is the presence of a co-infection—another pathogen transmitted during the same tick bite. Ticks can carry and transmit multiple infectious agents, and co-infections are common in endemic regions. These secondary infections cause symptoms not typically associated with Borrelia burgdorferi alone.
Co-infections such as Anaplasmosis (caused by the bacterium Anaplasma phagocytophilum) often present with non-specific flu-like symptoms that can include a cough. Similarly, some species of Mycoplasma, which can be transmitted alongside Borrelia, are known to cause respiratory tract infections. Mycoplasma pneumoniae is a well-known cause of “walking pneumonia,” and other Mycoplasma species can contribute to systemic symptoms. Coxiella burnetii, the agent of Q-fever, is another tick-borne illness that can cause a dry cough and respiratory issues.
When to Seek Further Testing and Diagnosis
If a persistent cough or other respiratory symptoms accompany suspected or confirmed Lyme disease, consult a healthcare provider for diagnosis. The cough may indicate a common, unrelated cause like a seasonal allergy, cold, or influenza. However, with known tick exposure, the cough warrants investigation for tick-borne co-infections that target the respiratory system or cause pulmonary involvement.
Diagnosis of co-infections often involves specific laboratory testing beyond the standard two-tiered serology used for Lyme disease. Molecular testing, such as PCR, may be used to detect the co-infection’s DNA in the blood, especially in early stages. Identifying these co-infections is important because some, like Babesiosis, require different medications than those used to treat Borrelia burgdorferi. Any unusual symptom like a persistent cough should prompt discussion with a physician about the possibility of multiple tick-borne illnesses.