If a tick has bitten, which tests should be ordered?

Tick Bites: Immediate Actions and Considerations

Proper Tick Removal Techniques

When a tick attaches to the skin, immediate and correct removal lowers the risk of disease transmission. Use fine‑tipped tweezers; avoid using fingers, knives, or burning methods.

Grasp the tick as close to the skin surface as possible.
Apply steady, even pressure to pull upward; do not twist or jerk.
Continue pulling until the entire mouthpart separates from the skin.
Disinfect the bite area with alcohol or iodine after removal.

Preserve the extracted tick in a sealed container with a damp cotton ball if identification or testing may be required later. Record the date of removal and monitor the bite site for redness, swelling, or a rash over the next weeks. Prompt medical evaluation should be sought if any systemic symptoms appear, as early detection guides appropriate laboratory testing.

When to Seek Medical Attention

A tick bite that results in any of the following conditions warrants prompt medical evaluation.

Fever of 38 °C (100.4 °F) or higher.
Expanding erythema with a central clearing (often described as a “bull’s‑eye” rash).
New onset of headache, neck stiffness, or photophobia.
Muscle or joint pain that develops within days of the bite.
Numbness, tingling, weakness, or facial droop suggesting neurologic involvement.
Persistent swelling or redness at the bite site beyond 48 hours.
History of immunosuppression, chronic illness, or pregnancy.

Seek care immediately if any symptom appears within two weeks after the bite, especially when the tick was attached for more than 24 hours or could not be identified. Early consultation allows appropriate laboratory testing, such as serologic assays for Borrelia, PCR for tick‑borne pathogens, and complete blood counts, which guide timely treatment. Delayed assessment increases the risk of complications and may limit therapeutic options.

Understanding Tick-Borne Diseases

Common Pathogens Transmitted by Ticks

Lyme Disease (Borrelia burgdorferi)

A tick bite that raises suspicion for Lyme disease warrants a targeted diagnostic approach. Early infection (≤ 4 weeks) may be confirmed by serologic testing, while later stages often require additional methods.

Enzyme‑linked immunosorbent assay (ELISA) for IgM and IgG antibodies; serves as the initial screen.
Western blot performed on a positive or equivocal ELISA; confirms specificity of IgM (≤ 4 weeks) and IgG (≥ 4 weeks) responses.
Polymerase chain reaction (PCR) on synovial fluid, cerebrospinal fluid, or skin biopsy; detects Borrelia DNA when serology is inconclusive or in neurologic and joint manifestations.
Culture of skin biopsy from erythema migrans or joint fluid; highly specific but low sensitivity, reserved for research or atypical cases.
Complete blood count and inflammatory markers (ESR, CRP); assess systemic involvement but are not diagnostic.

Interpretation depends on symptom onset. Positive IgM without IgG suggests recent infection; isolated IgG indicates established disease. Negative serology within the first two weeks does not exclude early infection; repeat testing after 2–4 weeks is advisable if clinical suspicion persists.

Anaplasmosis and Ehrlichiosis

When a patient reports a recent tick attachment, clinicians must consider the possibility of Anaplasma phagocytophilum infection (human granulocytic anaplasmosis) and Ehrlichia chaffeensis infection (human monocytic ehrlichiosis). Both pathogens are transmitted by Ixodes spp. and Amblyomma americanum, respectively, and share overlapping clinical presentations such as fever, headache, myalgia, and leukopenia.

Laboratory confirmation relies on specific assays:

Polymerase chain reaction (PCR) on whole blood – detects bacterial DNA during the acute phase; preferred for both Anaplasma and Ehrlichia because of high sensitivity before seroconversion.
Serology (indirect immunofluorescence assay, IFA) – measures IgG titers; a four‑fold rise between acute (≤7 days of symptom onset) and convalescent (2–4 weeks later) samples confirms infection. Single high titer may be supportive but less definitive.
Complete blood count with differential – typically reveals leukopenia, thrombocytopenia, and mild anemia; these findings are nonspecific but reinforce suspicion.
Peripheral blood smear – may show morulae within neutrophils (Anaplasma) or monocytes (Ehrlichia); low yield, useful only when microscopy is readily available.

A practical ordering strategy includes:

PCR for Anaplasma and Ehrlichia on the same specimen.
Paired IFA serology for each organism, collected at presentation and 2–4 weeks later.
CBC with differential to document cytopenias.
Peripheral smear review if immediate microscopy is feasible.

Prompt initiation of doxycycline is recommended while awaiting results, given the rapid progression of both diseases and the limited window for effective therapy.

Rocky Mountain Spotted Fever

A patient with a recent tick exposure and clinical features suggestive of Rocky Mountain spotted fever requires prompt laboratory evaluation. Early identification guides antimicrobial therapy and reduces morbidity.

Polymerase chain reaction (PCR) on whole blood – detects Rickettsia rickettsii DNA; most sensitive during the first 5 days of illness.
Indirect immunofluorescence assay (IFA) for IgM and IgG – standard serologic test; a single titer ≥1:256 supports diagnosis, but a four‑fold rise between acute and convalescent samples (taken 2–4 weeks apart) provides definitive confirmation.
Complete blood count (CBC) – commonly reveals thrombocytopenia and leukopenia.
Comprehensive metabolic panel – elevated hepatic transaminases and alkaline phosphatase are frequent findings.
Blood cultures – low yield for Rickettsia but performed to exclude secondary bacterial infections.

If initial serology is negative but clinical suspicion remains high, repeat IFA on a convalescent specimen and consider a second PCR assay. Empiric doxycycline should not be delayed pending results.

Tick-Borne Encephalitis (TBE)

Tick‑borne encephalitis (TBE) is a flaviviral infection transmitted by Ixodes ticks. After a bite, symptoms may appear after an incubation period of 7–14 days and include fever, headache, nausea, and, in severe cases, meningitis or encephalitis. Early recognition is essential because specific antiviral therapy is unavailable and management relies on supportive care.

Testing is warranted when the bite occurs in a TBE‑endemic area, the patient is unvaccinated, or neurological signs develop. The diagnostic work‑up should focus on detecting viral particles or the host immune response.

Serum IgM and IgG ELISA for TBE virus – first‑line serology; IgM appears within 7‑10 days, IgG seroconversion confirms infection.
Repeat serology after 10–14 days if initial results are negative but clinical suspicion persists.
Polymerase chain reaction (PCR) on blood or cerebrospinal fluid – useful during the early viremic phase, though sensitivity declines after the first week.
Cerebrospinal fluid analysis – pleocytosis with lymphocytic predominance, elevated protein, normal glucose; helps differentiate TBE from bacterial meningitis.
Complete blood count and inflammatory markers – supportive data; leukopenia or thrombocytopenia may be present.

Interpretation of results must consider vaccination status; a positive IgG in a vaccinated individual indicates immunity rather than acute infection. Negative serology early in the disease does not exclude TBE; repeat testing is recommended. Prompt identification allows appropriate monitoring and exclusion of other tick‑borne pathogens.

Babesiosis

Babesiosis should be considered in any patient who reports a recent tick exposure, especially in endemic regions of the Northeastern and Upper Midwestern United States. The organism, Babesia microti, can cause hemolytic anemia and may coexist with other tick‑borne infections such as Lyme disease and anaplasmosis, making targeted laboratory evaluation essential.

Recommended diagnostic work‑up

Complete blood count (CBC) with differential – often reveals anemia, thrombocytopenia, or leukopenia; these findings support the suspicion of babesiosis.
Peripheral blood smear – stained thin smear examined for intra‑erythrocytic ring forms and Maltese‑cross tetrads; provides rapid, direct evidence of parasitemia.
Polymerase chain reaction (PCR) for Babesia DNA – highly sensitive, detects low‑level infection, and confirms species; useful when smear results are negative but clinical suspicion remains high.
Serologic testing (indirect immunofluorescence assay or enzyme‑linked immunosorbent assay) – identifies IgM and IgG antibodies; valuable for retrospective diagnosis or when PCR is unavailable.
Additional tests for co‑infection – simultaneous ordering of Lyme disease (ELISA/Western blot) and anaplasmosis (PCR or serology) is advisable, given frequent co‑transmission by Ixodes ticks.

Interpretation of results should consider parasite load, patient immune status, and presence of co‑infecting agents. Prompt initiation of appropriate therapy depends on confirming Babesia infection through these laboratory studies.

Risk Factors for Infection

Tick exposure carries a variable probability of pathogen transmission. Assessment of infection risk guides the selection of laboratory investigations.

Key determinants of transmission include:

Attachment time exceeding 24 hours
Identification of Ixodes scapularis, Ixodes pacificus, Dermacentor, or Amblyomma species known to harbor Borrelia, Anaplasma, Ehrlichia, Rickettsia, or Powassan virus
Residence or travel to endemic regions (Northeast, Upper Midwest, Pacific Northwest, parts of the South)
Immunosuppression, including HIV infection, organ transplantation, or chronic corticosteroid therapy
Age under five years or over sixty years
Pregnancy or lactation
Presence of skin lesions such as expanding erythema, targetoid rash, or vesiculobullous eruptions
Systemic symptoms (fever, headache, myalgia, arthralgia) within two weeks of the bite

When one or more of these factors are present, clinicians should order the following tests:

Serologic assay for Borrelia burgdorferi IgM/IgG by ELISA, confirmed by Western blot if positive
PCR for Borrelia, Anaplasma, or Ehrlichia on whole blood when early disease is suspected
Complete blood count with differential to detect leukopenia or thrombocytopenia associated with Anaplasma/Ehrlichia infection
Liver function panel to identify transaminase elevations common in rickettsial or ehrlichial diseases
Serum PCR or IgM serology for Rickettsia rickettsii in regions where Rocky Mountain spotted fever is endemic
Powassan virus IgM ELISA or RT‑PCR in cases of neurologic involvement or severe headache

Risk assessment should be performed promptly after removal of the tick. The presence of high‑risk features justifies a comprehensive panel, whereas low‑risk encounters may warrant observation and repeat testing only if symptoms develop.

Diagnostic Testing for Tick-Borne Diseases

Initial Assessment and Symptom Evaluation

When a patient reports a recent tick encounter, the clinician must first establish the circumstances of the bite. Record the date of attachment, geographic region, type of environment, and whether the tick was fully removed. Inspect the bite site for engorgement, erythema, or a central punctum, and document any signs of inflammation or necrosis.

Next, evaluate the patient’s current complaints. Note the presence of a rash, especially a target‑shaped lesion, fever, chills, headache, fatigue, joint pain, or neurologic disturbances such as facial weakness or numbness. Compare symptom onset with the estimated duration of tick attachment to gauge the likelihood of early infection.

Laboratory investigations appropriate for this presentation include:

Complete blood count with differential to identify leukocytosis or thrombocytopenia.
Serum C‑reactive protein or erythrocyte sedimentation rate for inflammatory activity.
Enzyme‑linked immunosorbent assay (ELISA) for Borrelia burgdorferi antibodies, followed by a Western blot if the ELISA is positive.
Polymerase chain reaction (PCR) testing of blood or cerebrospinal fluid when neurologic symptoms are present.
Serologic panels for Anaplasma, Ehrlichia, and Babesia if the exposure area is endemic for these co‑pathogens.
Urinalysis and urine culture when urinary symptoms suggest possible co‑infection.

If initial serology is negative but the patient exhibits early signs, repeat testing in 2–4 weeks is advisable because antibody levels may not yet be detectable. In cases of severe or disseminated disease, consider imaging studies such as MRI of the brain or spinal cord to assess for meningitis or encephalitis.

Types of Laboratory Tests

Serological Tests

When a patient reports a recent tick attachment, serological evaluation targets the most common tick‑borne infections that generate detectable antibodies. The clinician should request assays that identify acute or past exposure to the relevant pathogens, considering the interval since the bite because antibody production varies over time.

Enzyme‑linked immunosorbent assay (ELISA) for Borrelia burgdorferi IgM and IgG, followed by a Western blot for confirmation of positive ELISA results.
Indirect immunofluorescence assay (IFA) for Rickettsia species, providing IgM and IgG titers that differentiate recent from prior infection.
Immunofluorescence or microagglutination test for Ehrlichia chaffeensis and Anaplasma phagocytophilum, reporting separate IgM and IgG levels.
Indirect fluorescent antibody test for Babesia microti, detecting IgM and IgG antibodies that rise during active disease.

Interpretation must account for the seroconversion window: IgM typically emerges 1–3 weeks after exposure, whereas IgG appears later and may persist. A single low‑titer IgM result without clinical correlation often lacks specificity; repeat testing after 2–3 weeks can confirm rising titers. Positive IgG in the absence of recent symptoms may indicate past infection rather than current disease.

In cases where serology is negative but clinical suspicion remains high, additional diagnostics such as polymerase chain reaction or blood smear examination should be considered. Nonetheless, the primary serologic panel listed above addresses the majority of tick‑borne pathogens encountered after a bite.

ELISA

After a tick attachment, laboratory confirmation of infection guides therapy. Enzyme‑linked immunosorbent assay (ELISA) provides quantitative detection of specific antibodies or antigens associated with tick‑borne pathogens. The test is especially valuable when clinical signs are ambiguous or when early treatment decisions depend on serologic confirmation.

Order an ELISA for Borrelia burgdorferi if erythema migrans is absent, if the bite occurred ≥ 24 hours ago, or if the patient presents with nonspecific flu‑like symptoms in an endemic area.
Use ELISA for Anaplasma phagocytophilum and Ehrlichia chaffeensis when leukopenia, thrombocytopenia, or elevated liver enzymes are observed after exposure.
Apply ELISA for Babesia microti in patients with hemolytic anemia, hemoglobinuria, or high‑grade fever, particularly in regions with known babesiosis transmission.
Consider ELISA for Rickettsia rickettsii in the presence of fever, headache, and a rash following a bite in areas where Rocky Mountain spotted fever is endemic.

Positive ELISA results should be confirmed with a more specific assay, such as Western blot for Lyme disease or PCR for intracellular organisms, to rule out cross‑reactivity and ensure accurate diagnosis.

Western Blot

Western blot serves as the confirmatory assay for suspected Lyme disease following an initial screening test. After a tick attachment, clinicians typically perform an enzyme‑linked immunosorbent assay (ELISA) to detect antibodies against Borrelia burgdorferi. A positive or equivocal ELISA result triggers a Western blot to differentiate true infection from cross‑reactivity.

The Western blot evaluates IgM and IgG antibodies against specific protein bands. Interpretation follows established criteria: for IgM, at least two of the 23‑kDa (OspC), 39‑kDa (BmpA), and 41‑kDa (Fla) bands must be present; for IgG, five of ten bands (including 18‑kDa, 23‑kDa, 28‑kDa, 30‑kDa, 39‑kDa, 41‑kDa, 45‑kDa, 58‑kDa, 66‑kDa, and 93‑kDa) are required. Positive IgM is reliable only within the first four weeks of symptom onset; IgG becomes informative after four weeks.

Western blot is ordered when:

ELISA yields a positive or borderline result.
Clinical presentation includes erythema migrans, arthralgia, neurologic signs, or cardiac involvement.
Persistent symptoms occur despite initial treatment, prompting re‑evaluation.
Differential diagnosis involves other spirochetal infections where serology may be ambiguous.

Limitations include reduced sensitivity in early infection, possible false‑positive results due to rheumatoid factor or other infections, and the necessity of laboratory expertise for band interpretation. Despite these constraints, Western blot remains the definitive serologic test to confirm or exclude Lyme disease after a tick bite.

PCR Testing

PCR testing provides rapid detection of tick‑borne pathogens by amplifying specific DNA sequences. The method is most useful when serologic responses have not yet developed or when a definitive organism identification is required for targeted therapy.

After a recent tick attachment, clinicians should consider ordering PCR assays for the following agents:

Borrelia burgdorferi – skin biopsy from the erythema migrans lesion or whole blood; positive result confirms Lyme disease before antibodies appear.
Anaplasma phagocytophilum – whole blood; detects early anaplasmosis when leukopenia and fever are present.
Ehrlichia chaffeensis – whole blood; useful for early ehrlichiosis, especially in patients with elevated liver enzymes.
Rickettsia rickettsii – skin biopsy from rash or whole blood; helps identify Rocky Mountain spotted fever before seroconversion.
Babesia microti – whole blood; PCR outperforms microscopy during low‑parasitemia phases.
Powassan virus – cerebrospinal fluid; PCR identifies neuroinvasive infection when IgM testing may be delayed.

Key considerations for PCR ordering:

Collect specimens before antimicrobial therapy, as treatment can reduce detectable DNA levels.
Use appropriate transport media and maintain cold chain to preserve nucleic acids.
Request quantitative PCR when disease severity assessment or treatment monitoring is needed.
Interpret results in conjunction with clinical presentation; a negative PCR does not exclude infection if sampling occurs late in the disease course.

Implementing these PCR tests early after a tick bite enhances diagnostic accuracy, guides antimicrobial selection, and reduces the risk of complications.

Direct Smear Microscopy

Direct smear microscopy provides rapid visualization of pathogens that may be transmitted by a tick. The technique involves spreading a small amount of patient material—such as skin scrapings from the bite site or peripheral blood—onto a glass slide, fixing the specimen, and staining with appropriate dyes (e.g., Giemsa, Wright, or acridine orange). Under light or fluorescence microscopy, characteristic organisms, including Babesia parasites, Borrelia spirochetes, or Anaplasma inclusions, can be identified within minutes.

Key indications for ordering a direct smear after a tick exposure include:

Presence of erythema migrans or a persistent rash suggestive of early Lyme disease.
Fever, chills, or malaise accompanied by laboratory evidence of hemolytic anemia, which raises suspicion for babesiosis.
Acute onset of leukopenia or thrombocytopenia in a patient with recent tick contact, indicating possible anaplasmosis or ehrlichiosis.
Neurologic symptoms (e.g., facial palsy, meningitis) emerging shortly after the bite, prompting evaluation for early neuroborreliosis.

Interpretation requires familiarity with morphological features: Borrelia appear as thin, helical organisms; Babesia manifest as intra‑erythrocytic ring forms or Maltese‑cross tetrads; Anaplasma inclusions are basophilic morulae within granulocytes. Positive findings support immediate antimicrobial therapy while awaiting confirmatory serology or PCR.

Limitations must be acknowledged. Sensitivity varies with pathogen load and specimen quality; early infection may yield false‑negative results. Microscopy does not differentiate between closely related species, and some agents (e.g., Rickettsia) are not reliably detected by smear. Consequently, direct smear microscopy should be combined with serologic testing, PCR, or culture when clinical suspicion remains high despite a negative smear.

In practice, ordering a direct smear is justified when rapid diagnosis influences early treatment decisions, especially for babesiosis and anaplasmosis, where prompt doxycycline or azithromycin therapy can prevent severe complications.

Timing of Tests for Optimal Accuracy

Acute Phase Testing

Acute phase testing evaluates the presence of tick‑borne pathogens before the immune response generates detectable antibodies. Prompt laboratory assessment guides early treatment and reduces the risk of complications.

Polymerase chain reaction (PCR) for Borrelia burgdorferi DNA in blood or skin biopsy.
PCR panels for Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Rickettsia species when clinical suspicion exists.
Direct microscopic examination of peripheral blood smear for intracellular organisms (e.g., Babesia spp.).
Complete blood count with differential to identify leukopenia, thrombocytopenia, or anemia.
Serum liver function tests (ALT, AST) and renal panel to detect organ involvement.
Early serology (IgM) for Lyme disease, ehrlichiosis, and anaplasmosis, recognizing that sensitivity may be limited in the first week.

These investigations provide the most reliable evidence of infection during the initial days after a tick attachment.

Convalescent Phase Testing

A tick bite warrants initial diagnostic evaluation, but many infections become detectable only after the immune response has matured. The convalescent phase, typically defined as 2–4 weeks post‑exposure, provides a window in which serologic markers rise sufficiently for reliable interpretation.

During this interval, clinicians should request repeat serology to confirm or exclude infection. The principal assays include:

Borrelia burgdorferi – two‑tier testing (ELISA followed by immunoblot) performed on an acute sample and a convalescent sample; a four‑fold rise in IgG titer is diagnostic.
Anaplasma phagocytophilum – indirect immunofluorescence assay (IFA) or ELISA; compare acute and convalescent IgG levels for a significant increase.
Ehrlichia chaffeensis – IFA or ELISA with paired sera; a rising IgG titer confirms recent infection.
Babesia microti – indirect immunofluorescence or ELISA; a ≥ four‑fold increase in IgG supports diagnosis.
Rickettsia spp. – IFA for spotted‑fever group; a rise in IgG between paired samples indicates infection.

Molecular methods such as PCR are most useful during the early phase when pathogen DNA is present in blood or tissue; they lose sensitivity in the convalescent stage and are therefore not routinely ordered for follow‑up.

Interpretation hinges on documented seroconversion or a marked rise in antibody titer between the acute and convalescent specimens. A static titer or declining levels suggest that the initial exposure did not result in a clinically significant infection, allowing clinicians to discontinue empiric therapy or avoid unnecessary treatment.

Interpretation of Test Results

When a patient presents after a tick exposure, laboratory findings must be linked to the timing of the bite, the species of tick, and the clinical picture.

Serologic testing for Borrelia burgdorferi follows a two‑tier algorithm. A positive enzyme immunoassay (EIA) or immunofluorescence assay (IFA) requires confirmation by Western blot. Interpretation hinges on the stage of infection: IgM bands are significant only within the first four weeks, while IgG bands become reliable after that period. Isolated IgM positivity beyond one month suggests a false‑positive result; isolated IgG without IgM after early disease may indicate established infection or past exposure.

Polymerase chain reaction (PCR) assays detect pathogen DNA in blood, cerebrospinal fluid, or skin biopsies. A positive PCR result confirms active infection, but a negative result does not exclude disease because sensitivity varies with specimen type and disease stage. Positive PCR in cerebrospinal fluid, for example, strongly supports neuroborreliosis.

Complete blood count (CBC) and differential provide ancillary information. Lymphocytosis or mild anemia may accompany early disseminated disease, whereas leukocytosis is uncommon and may point to a secondary bacterial infection.

Elevated liver transaminases (ALT, AST) often accompany early disseminated Lyme disease. Persistent elevation after treatment warrants assessment for alternative hepatic pathology.

A concise interpretive framework:

Positive EIA/IFA + confirmatory IgM Western blot (≤4 weeks): early Lyme disease; initiate antimicrobial therapy.
Positive EIA/IFA + confirmatory IgG Western blot (>4 weeks): established infection; treat accordingly.
Isolated IgM positivity >1 month: likely false positive; correlate with clinical findings before treatment.
Positive PCR in sterile site: active infection; consider more aggressive or prolonged therapy.
Negative PCR with positive serology: consistent with early or late disease; serology guides management.
Abnormal CBC or liver enzymes: supportive evidence; monitor for resolution post‑treatment.

Interpretation must always integrate laboratory data with symptom onset, rash characteristics, and exposure history to avoid misdiagnosis and unnecessary antimicrobial use.

Post-Exposure Prophylaxis and Treatment

Antibiotic Prophylaxis Guidelines

When a tick attachment is confirmed, the clinician must assess the risk of infection and decide whether antimicrobial prophylaxis is warranted. Decision‑making relies on epidemiologic factors, duration of attachment, and the presence of specific pathogens in the region.

Key elements of antibiotic prophylaxis guidance include:

Indication – Prophylaxis is recommended only if the tick is identified as a vector for Borrelia burgdorferi (e.g., Ixodes scapularis or Ixodes pacificus) and has been attached for ≥36 hours in an endemic area. Other tick‑borne illnesses (e.g., anaplasmosis, babesiosis) do not have established prophylactic regimens.
Agent – A single dose of doxycycline, 200 mg for adults or 4 mg/kg (maximum 200 mg) for children ≥8 years, is the preferred choice. Doxycycline provides coverage for B. burgdorferi and co‑transmitted agents such as Anaplasma phagocytophilum.
Timing – The dose must be administered within 72 hours of tick removal to achieve optimal efficacy.
Contraindications – Pregnant or lactating women, children under 8 years, and individuals with known doxycycline hypersensitivity should not receive this prophylaxis; alternative strategies focus on close monitoring rather than antimicrobial intervention.
Follow‑up testing – Baseline serology for Lyme disease is not routinely required before prophylaxis, but clinicians should arrange for subsequent serologic evaluation if symptoms develop within 30 days, including ELISA and confirmatory Western blot.

Implementation of these guidelines reduces the likelihood of early Lyme disease manifestation while avoiding unnecessary antibiotic exposure. Clinical judgment remains essential, especially in areas where tick species differ or where resistance patterns evolve.

Treatment Protocols for Specific Diseases

A tick bite warrants prompt evaluation for vector‑borne infections. Laboratory confirmation guides antimicrobial selection and prevents disease progression.

Lyme disease

Test: two‑tier serology (ELISA followed by Western blot) or PCR of synovial fluid in late arthritis.
Treatment: doxycycline 100 mg twice daily for 10–21 days; amoxicillin or cefuroxime for patients unable to take tetracyclines; intravenous ceftriaxone for neurologic or cardiac involvement.

Anaplasmosis

Test: PCR of whole blood, peripheral smear for morulae, or serology (acute and convalescent titers).
Treatment: doxycycline 100 mg twice daily for 7–14 days; alternative: minocycline if doxycycline contraindicated.

Ehrlichiosis

Test: PCR of blood, peripheral smear for intracytoplasmic inclusions, or serologic conversion.
Treatment: doxycycline 100 mg twice daily for 7–14 days; extended course for severe or immunocompromised patients.

Babesiosis

Test: thick and thin blood smears, PCR, or serology for Babesia microti.
Treatment: atovaquone 750 mg with azithromycin 500 mg daily for 7–10 days; severe disease requires clindamycin plus quinine for 7–10 days, sometimes combined with exchange transfusion.

Rocky Mountain spotted fever

Test: PCR of blood or skin biopsy, immunofluorescence assay (IFA) with paired sera.
Treatment: doxycycline 100 mg twice daily for 7–14 days, initiated empirically without waiting for results due to rapid progression.

Tick‑borne encephalitis

Test: IgM and IgG ELISA, confirmed by neutralization assay.
Treatment: supportive care; no specific antiviral therapy proven effective; early antiviral trials (e.g., ribavirin) remain investigational.

Southern tick‑associated rash illness (STARI)

Test: exclusion of Lyme disease by negative serology; skin biopsy may show nonspecific inflammation.
Treatment: doxycycline 100 mg twice daily for 10 days, mirroring Lyme protocol despite limited evidence.

When multiple pathogens are suspected, a broad initial regimen of doxycycline covers most bacterial tick‑borne diseases. Adjustments follow definitive test results. Timely ordering of targeted diagnostics and evidence‑based antimicrobial regimens reduces morbidity and prevents chronic sequelae.

Prevention and Awareness

Personal Protective Measures

Wear long sleeves and long pants, tucking pants into socks or boots, when entering wooded or grassy areas. Apply EPA‑registered repellents containing DEET, picaridin, or IR3535 to exposed skin and clothing, reapplying according to product instructions. Treat footwear and legwear with permethrin, following safety guidelines for topical application.

Perform a thorough body inspection within 24 hours of leaving the environment. Use a fine‑toothed comb or gloved fingers to locate attached ticks, focusing on scalp, behind ears, underarms, and groin. Remove any tick promptly with fine‑point tweezers, grasping close to the skin and pulling straight upward without crushing the body. Clean the bite site with antiseptic and wash hands thoroughly.

Document the tick’s appearance, estimated attachment time, and location of the bite. Retain the specimen in a sealed container for potential laboratory identification, especially if symptoms develop. Maintain a personal log of exposures and any subsequent symptoms to facilitate timely medical evaluation and appropriate laboratory testing.

Adopt routine preventive habits: avoid high‑grass paths, stay on cleared trails, and conduct post‑exposure checks after each outdoor activity. Consistent use of these measures reduces the likelihood of disease transmission and supports accurate diagnostic decision‑making when a bite occurs.

Tick Control in the Environment

Effective environmental tick control reduces the likelihood of disease transmission and informs the selection of laboratory investigations after a bite. Integrated strategies combine habitat modification, chemical interventions, and personal protection measures.

Remove leaf litter, tall grasses, and brush from residential yards and play areas.
Maintain a cleared perimeter of at least three feet around structures, using mulch or gravel to deter questing ticks.
Apply EPA‑registered acaricides to high‑risk zones on a schedule consistent with product labeling; rotate active ingredients to prevent resistance.
Treat domestic animals with veterinarian‑approved tick preventives and regularly inspect them for attached ticks.
Install fencing to limit wildlife entry, especially deer, which serve as primary hosts for adult ticks.
Encourage landscaping with tick‑repellent plants such as rosemary, lavender, or lemongrass, while avoiding dense, humid microhabitats.

These actions lower tick density, decreasing the probability that a patient will encounter an infected vector. When a bite is confirmed, clinicians should order appropriate serologic or molecular tests based on the regional prevalence of tick‑borne pathogens, guided by the reduced exposure risk achieved through environmental management.