Does Lyme Disease Affect Men Differently Than Women?

Men may show Lyme differently early
Testing may be positive more often in men
Persistent illness patterns also differ

Does Lyme disease affect men differently than women? Research suggests that it can. Men and women can develop the same major manifestations of Lyme disease, but emerging studies have identified differences in early antibody testing, rash size, disease severity, symptoms, diagnostic patterns, and persistent illness.^1-3

Some of the findings are surprising. Men may be more likely to have positive antibody tests and objective signs of more severe disease during early Lyme disease. Yet studies of patients with persistent or chronic symptoms contain substantially more women, and women in one large patient registry reported greater symptom severity, longer diagnostic delays, and more functional impairment.^1,2

These findings do not mean that Lyme disease follows a predictable male or female pattern in every patient. They suggest instead that biological sex, exposure patterns, immune responses, diagnostic practices, and other factors may influence how Lyme disease is recognized and experienced.

For the companion discussion from the female perspective, see Does Lyme Disease Affect Women Differently?

Are men more likely to get Lyme disease?

Reported Lyme disease cases have often shown a male predominance, although the reasons are not fully understood and may include differences in tick exposure, behavior, healthcare seeking, biology, and case detection.

A 2024 study published in the CDC journal Emerging Infectious Diseases examined 7,762 reported Lyme disease cases in Ontario, Canada, from 2015 through 2022. Among cases with male or female sex recorded, 56.3% were male and 43.3% were female. Annual Lyme disease incidence rates were higher among males.³

Men were also more likely to report activities in wooded areas or tall grass where blacklegged ticks are commonly encountered.³

This is an important distinction. A higher number of reported cases among men does not necessarily prove that men are biologically more susceptible to Borrelia burgdorferi. Differences in outdoor exposure and behavior may contribute to the pattern.

Does early Lyme disease look different in men?

A 2026 prospective Johns Hopkins study provides some of the strongest recent evidence that early Lyme disease may present differently according to biological sex.¹

Rebman and colleagues studied 243 antibiotic-naïve adults with early Lyme disease and a diagnostic erythema migrans rash. The researchers compared 125 men with 118 women and also examined differences according to menopausal status.¹

Men had higher odds of several objective indicators associated with early disease severity. These included greater two-tier antibody positivity and a higher overall disease severity score. Men also tended to have larger erythema migrans rashes and more frequent abnormalities in measures such as liver function tests and the neutrophil-to-lymphocyte ratio.¹

Importantly, men and women had similar durations of illness before diagnosis. The differences therefore could not simply be explained by men waiting longer before seeking medical care.¹

Are Lyme disease blood tests more likely to be positive in men?

Possibly, particularly during early infection.

In the 2026 Johns Hopkins cohort, men had significantly higher odds of testing positive by standard two-tier Lyme disease serology than women. After adjustment for several potential confounding factors, men had 1.77 times the odds of two-tier antibody positivity compared with women.¹

The difference was even greater when men were compared specifically with premenopausal women. Men had 2.93 times the odds of two-tier antibody positivity compared with premenopausal women. No significant difference was found between men and postmenopausal women.¹

This finding deserves attention because most conventional Lyme disease blood tests depend on the patient’s antibody response rather than directly detecting Borrelia burgdorferi.

It also reinforces why Lyme disease testing needs to be interpreted within the clinical context. Early Lyme disease tests can be negative even in patients who are infected, and individual immune responses may differ. For a broader discussion, see Lyme Disease Test Accuracy.

Do men have larger Lyme disease rashes?

Research suggests that erythema migrans rashes may, on average, be larger in men.

The 2026 prospective study included rash size as one of the objective indicators used to evaluate early Lyme disease severity and found a pattern of more pronounced early disease characteristics among men.¹

Earlier research has also reported sex-related differences in erythema migrans size. These findings do not mean that rash size can be used to determine whether a patient has more serious Lyme disease or that a small rash should be considered less important.

Erythema migrans can vary considerably in size, appearance, location, and rate of expansion. Individual patients may therefore look very different from the average patterns described in research studies.

Do men have different Lyme disease symptoms?

Men and women in the 2026 study reported a similar overall number of acute symptoms, but there were differences in some individual symptoms.¹

Women more often reported heart palpitations and vomiting, with photophobia also trending higher among women. Men were more likely to report difficulty sleeping.¹

These differences should not be turned into rigid diagnostic rules. A man with Lyme disease can develop palpitations, nausea, light sensitivity, fatigue, pain, neurologic symptoms, or virtually any other recognized manifestation of the illness.

Likewise, the absence of a symptom reported more frequently in men does not make Lyme disease less likely.

The value of these studies is not in creating separate male and female symptom checklists. Their value is in recognizing that the average presentation may differ enough to influence diagnosis and research findings.

Why might men show stronger signs of early Lyme disease?

The reason remains uncertain.

Biological sex can influence innate and adaptive immune responses through genetic, hormonal, and immunologic mechanisms. However, the Lyme disease studies do not establish that testosterone, estrogen, or another hormone directly explains the differences observed between men and women.

One particularly interesting finding from the 2026 study involved menopause. Postmenopausal women resembled men more closely than premenopausal women in both two-tier antibody reactivity and measures of acute disease severity.¹

This pattern raises the possibility that hormonal changes may contribute to differences in immune response. But menopause is also associated with age and other physiologic changes, and the study was not designed to prove a specific hormonal mechanism.

For now, it is more accurate to say that biological sex and menopausal status were associated with differences in early Lyme disease presentation rather than saying hormones caused those differences.

If men have more reported Lyme disease, why are women more common in persistent illness studies?

This is one of the most interesting unanswered questions.

A 2023 analysis of the MyLymeData patient registry examined 2,170 patients who reported persistent or chronic Lyme disease symptoms after antibiotic treatment. The population was predominantly female.²

Women reported longer diagnostic delays, more previous misdiagnoses, greater severity of several symptoms, and more functional impairment than men.²

Women reported significantly greater severity of fatigue, muscle aches, joint pain, sleep impairment, gastrointestinal complaints, and headache. They were also more likely to report disability, more days confined to bed, and the need for special equipment because of their illness.²

In contrast, men in this persistent-illness registry generally reported less severe impairment in these areas.

This creates an apparent paradox: men appear somewhat more frequently in acute Lyme disease surveillance and may show stronger objective markers during early disease, while women are more heavily represented in many populations with persistent symptoms.^1-3

Are men diagnosed with Lyme disease sooner?

The MyLymeData study suggests that diagnostic experiences may differ between men and women with persistent illness.

Women in the registry reported longer delays before receiving a Lyme disease diagnosis and were more likely to report having been diagnosed previously with conditions such as fibromyalgia, chronic fatigue syndrome, or a psychiatric disorder.²

Men reported fewer of these diagnostic delays and misdiagnoses.

That does not establish that male patients are routinely diagnosed correctly or quickly. Men can also experience delayed Lyme disease diagnosis, particularly when they do not recall a tick bite, do not develop a recognized rash, have negative early testing, or present with nonspecific symptoms.

These diagnostic challenges are discussed further in Delayed Lyme Diagnosis: Why It Happens and Why It Matters.

Do men respond better to Lyme disease treatment?

The available evidence does not support that conclusion.

One of the most clinically important findings from the MyLymeData analysis was that despite differences in symptom severity, diagnostic delay, and functional impairment, there was no statistically significant difference between men and women in reported antibiotic treatment response or treatment side effects.²

The majority of both men and women reported some improvement in symptoms since beginning antibiotic treatment.²

This distinction matters. Finding sex-related differences in disease presentation does not mean that men inherently respond better to treatment or that women inherently respond worse.

Treatment response remains highly individual and may be influenced by the stage of illness, diagnostic delay, severity, previous treatment, immune response, other medical conditions, and additional clinical factors.

Could diagnostic testing partly explain the difference?

Possibly.

If men with early Lyme disease are more likely to develop detectable antibody responses, they may be more likely to satisfy laboratory-based diagnostic or research criteria during early illness.¹

Conversely, lower early antibody positivity in some women could potentially contribute to missed or delayed recognition when clinicians depend heavily on serology.

However, this remains a hypothesis rather than a proven explanation for the later predominance of women in persistent-illness populations.

Diagnostic delay itself may also influence outcomes. A patient whose illness is recognized and treated promptly may follow a different clinical course from someone whose diagnosis is delayed for months or years.

What do these differences mean for men with Lyme disease?

Men should not assume that Lyme disease will necessarily be easier to diagnose or less likely to become persistent.

Population-level differences describe averages. They do not predict what will happen to an individual patient.

A man can have an atypical rash, a negative Lyme disease test, severe neurologic or musculoskeletal symptoms, delayed diagnosis, or prolonged symptoms following treatment.

Likewise, stronger average antibody responses among men do not mean that every infected man will test positive.

The practical lesson is that clinicians should consider the entire clinical picture—including exposure history, symptoms, physical findings, timing of testing, laboratory results, previous treatment, and alternative diagnoses—rather than assuming Lyme disease follows one characteristic male or female pattern.

Frequently Asked Questions

Are men more likely than women to get Lyme disease?

Reported Lyme disease incidence has often been higher among men. In an Ontario study of 7,762 reported cases from 2015 through 2022, 56.3% of cases were male and 43.3% were female. Differences in outdoor exposure, behavior, biology, healthcare seeking, and case detection may all contribute.

Are Lyme disease tests more likely to be positive in men?

In a 2026 prospective study of adults with early Lyme disease and erythema migrans, men had higher odds of standard two-tier antibody positivity than women. This difference was particularly pronounced when men were compared with premenopausal women. The finding does not mean that every man with Lyme disease will test positive.

Do men have more severe Lyme disease?

Men in one prospective early Lyme disease study had higher scores on objective measures of acute disease severity. However, women with persistent illness in a separate patient registry reported greater symptom severity and functional impairment. Severity therefore appears to depend partly on which stage and patient population is being studied.

Do men and women have different Lyme disease symptoms?

Most Lyme disease manifestations can occur in either sex. In one early Lyme disease study, men and women reported a similar overall number of symptoms, although women more often reported palpitations and vomiting while men more often reported sleep difficulty. These are population-level differences and should not be used as rigid diagnostic rules.

Do men respond better to Lyme disease treatment?

Not based on the MyLymeData study. Although men and women differed in several measures of persistent illness, researchers found no statistically significant difference in reported antibiotic treatment response or side effects.

Clinical Takeaway

Research increasingly suggests that biological sex may be associated with meaningful differences in Lyme disease presentation. Men appear somewhat more frequently in reported acute Lyme disease populations and, in a recent prospective study, showed greater early two-tier antibody positivity and stronger objective markers of acute disease severity.

At the same time, women are more heavily represented in studies of persistent illness and have reported greater diagnostic delays, misdiagnosis, symptom severity, and functional impairment.

These findings should not be interpreted to mean that Lyme disease is mild in men or severe in women. Individual presentations vary considerably, and the mechanisms underlying these population differences remain incompletely understood.

This article is for informational purposes only and is not intended as medical advice. Patients should consult a qualified healthcare professional for diagnosis and treatment.

The emerging evidence suggests that Lyme disease may follow different patterns in men and women, making sex an important variable to consider in research, diagnosis, and clinical care.

Related Articles

For additional information about Lyme disease presentation, persistent illness, and early recognition, see:

Persistent Infection in Lyme Disease
Lyme Disease Symptoms
Why Early Lyme Disease Symptoms Are Often Missed
Neurologic Lyme Disease Symptoms

References

1. Rebman AW, Yang T, Aucott JN. Sex and menopause-based differences in presentation of early Lyme disease: A prospective cohort study. Clinical and Experimental Medicine. 2026;26(1):139. doi:10.1007/s10238-026-02063-0.
2. Johnson L, Shapiro M, Janicki S, Mankoff J, Stricker RB. Does Biological Sex Matter in Lyme Disease? The Need for Sex-Disaggregated Data in Persistent Illness. International Journal of General Medicine. 2023;16:2557-2571. doi:10.2147/IJGM.S406466.
3. Adams JA, Osasah V, Paphitis K, Danish A, Mather RG, Russell CA, Pritchard J, Nelder MP. Age- and Sex-Specific Differences in Lyme Disease Health-Related Behaviors, Ontario, Canada, 2015-2022. Emerging Infectious Diseases. 2024;30(10).

Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.

Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention