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Infectious Disease

Theodoros F. Katsivas, MD

Sees patients in Fremont, CA · California

Summary

Dr. Theodoros F. Katsivas, MD is an infectious disease doctor at 1999 Mowry Ave, Fremont, CA 94538. Phone: (510) 770-8040. Accepts Medicare assignment. NPI 1679526164. Source: CMS National Downloadable File, updated October 2, 2026.

  • Specialty: Infectious disease doctor (Medicare lists Infectious Disease)
  • Address: 1999 Mowry Ave, Fremont, CA 94538 · Directions
  • Phone: (510) 770‑8040
  • Medicare: Accepts Medicare assignment
  • Group practice: Bay Area Community Health
  • Medical school: graduated 1994 (32 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Theodoros F. Katsivas, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Theodoros F. Katsivas accept Medicare assignment?
Yes. Medicare's clinician data says Theodoros F. Katsivas accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
What is Theodoros F. Katsivas's NPI number?
1679526164. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Theodoros F. Katsivas is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Theodoros F. Katsivas as a member of this group (CMS data updated October 2, 2026).

  • Bay Area Community Health102 clinicians in the group

Specialties

Find other Infectious Disease doctors in California →

Other infectious disease doctors in Fremont

Clinicians with the same Medicare primary specialty in Fremont, CA — not a recommendation.

All infectious disease doctors in Fremont →

Other clinicians in Bay Area Community Health

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Graduation year1994 (32 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1679526164
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians