NPI registry status
Active
2026 NPPES data Infectious Disease Physician NPI 1225078421 DO
Verify on CMS → Leonard Mermel, DO
Infectious Disease Physician in Providence, Rhode Island.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 8,537 in Infectious Disease Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
What the federal data shows
Leonard Mermel, DO is an Infectious Disease Physician in Providence, Rhode Island, listed in the federal CMS National Provider Identifier registry.
- #69
- Infectious Disease Physician rank among Rhode Island specialties
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Federal trust snapshot
What official records show about Leonard Mermel, DO
Bare NPI registry listing — limited federal enrichment beyond basic enumeration. Verify all credentials with official sources.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1225078421), first enumerated 06/07/2006.
Source: CMS NPPES
- Not in federal data
Medicare Part D participation
No 2023 Medicare Part D prescribing volume appears in the CMS public file for this NPI (may reflect specialty, new enrollment, or non-prescribing role).
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Practices in an ABMS-board-eligible specialty; board certification not confirmed in federal records.
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1225078421 · Infectious Disease Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-NONE · BOOK-THIN · PHOTO-ENUM
- NPI-10 1225078421
- ENUM-LEGACY 2006
- TAX-MID 9K Infectious Disease
- RX-NONE No Part D
- BOOK-THIN 49 in Rhode Island
- PHOTO-ENUM Mohammed Miradi · 2006
◑
Board-eligible specialty (heuristic, not verified)
Leonard Mermel, DO practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Leonard Mermel, DO?
Quality data not reportedPrimary specialty
Infectious Disease Physician
Specialty distribution in Rhode Island
How Infectious Disease Physician compares to other specialties among Rhode Island providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Infectious Disease Physician. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Practice Address
Provider Details
| NPI | 1225078421 |
|---|---|
| Specialty | Infectious Disease Physician |
| Credentials | DO |
| Gender | Male |
| NPI Issued | 06/07/2006 |
Infectious Disease Physician Overview
How Leonard Mermel, DO fits within the Infectious Disease Physician landscape nationally.
8,537
Infectious Disease Physician Providers in US
54
States with Infectious Disease Physician
807
Avg Claims per Provider
Nationwide Infectious Disease Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Mermel, both outside Rhode Island so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Infectious Disease Physician Providers in Rhode Island
Other clinicians with the same primary specialty enrolled in Rhode Island, drawn from the same CMS NPPES roster as Mermel.
One of 49 Infectious Disease Physician providers enrolled in Rhode Island, 5 are shown here.
Dr. Jennifer Adelson-Mitty
MD
Providence, RI
Dr. Tanya Ali
MD
Providence, RI
Dr. Rebecca Burns
MD
Providence, RI
Dr. Angela Caliendo
M.D., PH.D.
Providence, RI
Dr. Eirini Christaki
M.D.
Providence, RI
Compare Infectious Disease Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Leonard Mermel, DO's specialty? ▼
Leonard Mermel, DO specializes in Infectious Disease Physician and practices in Providence, Rhode Island. Credentials: DO.
Where is Leonard Mermel, DO located? ▼
Leonard Mermel, DO is located at 110 LOCKWOOD ST, Providence, RI, 02903. Phone: (401) 793-2985.
What is Leonard Mermel, DO's NPI number? ▼
Leonard Mermel, DO's National Provider Identifier (NPI) is 1225078421, issued on 06/07/2006.
How many Infectious Disease Physician providers are there in the US? ▼
There are 8,537 Infectious Disease Physician providers across 54 states in the US. The average Infectious Disease Physician provider writes 807 Medicare Part D claims per year.
Does Leonard Mermel, DO accept Medicare? ▼
Leonard Mermel, DO appears in CMS Medicare data. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Leonard Mermel, DO's credentials? ▼
Leonard Mermel, DO's NPI is 1225078421 with credentials DO. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of August 2026 (NPPES) / 2024 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.