• Any gender

• Aged 18+

• Baseline EQ-VAS ≤70; EQ-VAS before the index infection ≥80 (this information is collected as part of the baseline survey).

• Diagnosed with only one of the following conditions:

• Long Covid

• Documented clinical history of confirmed or suspected acute COVID-19 infection a minimum of 3 months prior to contact with the study team

• Formal diagnosis of Long Covid from a physician

• Post-treatment Lyme disease syndrome

• Diagnosis will be based on participants meeting either Group 1 or Group 2 criteria of the Columbia Clinical Trial Network PTLDS diagnostic criteria:

‣ Group 1. Well-defined Lyme disease meeting CDC Surveillance Definition Erythema Migrans History of possible exposure to a high incidence county or state (or an adjacent area) Erythema migrans rash

• EM 1: EM rash diagnosed by HCP previously (either in person or telemedicine)

∙ EM 1A: MOA self-report \& medical record documentation of rash \> 5 cm

∙ EM 1B: MOA: self-report and medical record documentation of EM rash but not size

∙ EM 1C: MOA: self-report \& rash misdiagnosed in medical record as cellulitis/spider bite

∙ EM 1D: MOA: self-report and either: photo of EM or Class 1 lab test confirmation within 4 weeks of illness onset OR

∙ Disseminated objective manifestation with lab test confirmation of Bb infection

∙ Clinical history includes at least one of the following symptoms/signs, which are not better accounted for by another cause (MOA: medical records and/or self-report).

∙ Neurologic: Lymphocytic Meningitis ; Encephalitis; Encephalomyelitis Cranial Neuritis (especially facial palsy); Radiculoneuropathy; Other Neurologic Signs (with objective measures) : Encephalopathy, Polyneuropathy

∙ Carditis: 2nd or 3rd degree AV block; Myocarditis; Pericarditis

∙ Lyme arthritis: Recurrent joint swelling in one or more joints

∙ Dermatologic: Disseminated EM (satellite) or Acrodermatitis atrophicans AND

∙ Lab test Confirmation (requires at least one of the Class 1 lab tests) (MOA: self-report \& documentation)

⁃ Group 2. Probable

• 2A. Chronic Multisystem Symptoms attributed to Lyme disease (insufficient to meet Group 1) and not better explained by another diagnosis and patient has evidence of positive lab results on a Class 1 lab test (or 4 of 10 bands for IgG Western blot (WB)) (MOA: self-report with lab documentation Class 1 lab test confirmation (excluding IgM WB) Highly suggestive IgG WB (4 of 10 bands) OR

∙ 2B. EM rash by history after exposure to a Lyme-endemic area but not previously diagnosed by a HCP and no photo or Class 1 lab test confirmation is available (MOA: self-report) OR

∙ 2C. Viral like illness (not better explained by other cause) with indeterminate or + enzyme immunoassay (EIA) with positive IgM WB or positive Class 1 lab test (within 4 weeks of illness onset after known exposure to a Lyme high-incidence area for standard two-tiered (STT) IgM) (MOA: medical records, lab test and self-report) (MOA: lab test and self-report) OR

∙ 2D. Viral like illness (not better explained by other cause) with indeterminate or positive EIA with positive IgM WB or positive Class 1 lab test (within 6 months of illness onset after known exposure to a Lyme high-incidence area for standard two-tiered (STT) IgM)

• (MOA: medical records, lab test and self-report)

• (MOA: lab test and self-report)

• ME/CFS

• Formal diagnosis of ME/CFS prior to 2020 from a physician

• Actively symptomatic such that the 2011 International Criteria for ME/CFS is met at time of screening