INFECTIOUS DISEASE ASSOCIATES OF ORANGE COUNTY, INC.
NPI 1326403130
Internal Medicine - Infectious Disease in Santa Ana, CA

Q: What is Infectious Disease Associates Of Orange County, Inc.'s specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Active since December 21, 2015

999 N TUSTIN AVE STE 224, SANTA ANA, CA 92705(714) 664-0045(714) 664-0049 Get Directions Write a Review

NPPES record last updated: August 14, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Aug 14, 2025, Jun 7, 2021, Dec 21, 2015 (3 updates tracked since 2015).

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About Infectious Disease Associates Of Orange County, Inc. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

INFECTIOUS DISEASE ASSOCIATES OF ORANGE COUNTY, INC. (NPI 1326403130) is a healthcare organization registered as an infectious disease in Santa Ana, California and active in the NPI registry since December 2015. The organization lists Tuan V Ta, Owner, as its authorized official.

NPPES Registry Identity

NPI1326403130

Entity TypeOrganization

Primary Taxonomy207RI0200X

Legal Business NameINFECTIOUS DISEASE ASSOCIATES OF ORANGE COUNTY, INC.

Location Address999 N TUSTIN AVE STE 224Santa Ana, CA 92705-6506

Mailing Address2321 E 4th Street, Suite C #637Santa Ana, CA 92705-3606 · (714) 664-0045 · Fax (714) 664-0049

Phone(714) 664-0045

Fax(714) 664-0049

Organization SubpartNo

Authorized OfficialTuan V TaOwner · (714) 664-0045

Enumeration DateDecember 21, 2015

Last NPPES UpdateAugust 14, 20253 updates tracked since enumeration

NPPES CertifiedAugust 14, 2025

✔ NPI 1326403130 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Infectious DiseaseAllopathic & Osteopathic Physicians

Taxonomy Code207RI0200X

Definition

An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine.

999 N TUSTIN AVE STE 224, Santa Ana, CA 92705

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Other Identifiers 1

Medicaid1326403130CA

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Infectious Disease Associates Of Orange County, Inc. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 9 clinicians reassign Medicare billing to Infectious Disease Associates Of Orange County, Inc., which bills Medicare for the services they deliver. Of these, 2 practice at this address and 6 within 10 miles. They are listed nearest first.

Clinicians, nearest first (9)

Tuan Ta, MD

Infectious Disease

NPI 1114103124

999 N TUSTIN AVE STE 224
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts MedicareSame address

Nicholas Nguyen

Infectious Disease

NPI 1689239584

999 N TUSTIN AVE STE 109
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts MedicareSame address

Marianne Go-Wheeler, M.D.

Infectious Disease

NPI 1740627280

999 N TUSTIN AVE STE 109
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts Medicare0.1 mi

Roma Patel, M.D.

Infectious Disease

NPI 1740523406

999 N TUSTIN AVE STE 109
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts Medicare0.1 mi

Puneet Chahal, MD

Infectious Disease

NPI 1811155476

720 N TUSTIN AVE 201
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts Medicare0.2 mi

Thao Lai

Nurse Practitioner

NPI 1255793840

720 N TUSTIN AVE 201
Santa Ana, CA 92705

(714) 664-0045

✔ PECOS✔ Accepts Medicare0.2 mi

Melissa King, MD

Infectious Disease

NPI 1417052341

2699 ATLANTIC AVE
Long Beach, CA 90806

(562) 426-3333

✔ PECOS✔ Accepts Medicare21 mi

Duc Nguyen, FNP-C

Nurse Practitioner

NPI 1376060319

19353 VICTORY BLVD
Reseda, CA 91335

(714) 323-0419

✔ PECOS✔ Accepts Medicare51 mi

Rex Justin Lim, MD

Infectious Disease

NPI 1346528031

120 E 2ND ST FL 1
Erie, PA 16507

(814) 877-7072

✔ PECOS✔ Accepts Medicare2,122 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Infectious Disease Associates Of Orange County, Inc.'s NPI number?

The NPI number for Infectious Disease Associates Of Orange County, Inc. is 1326403130. It was assigned to this organization in the NPPES registry on December 21, 2015.

Where is Infectious Disease Associates Of Orange County, Inc. located?

Infectious Disease Associates Of Orange County, Inc. is located at 999 N Tustin Ave Ste 224, Santa Ana, CA 92705. The listed phone number is (714) 664-0045.

What is Infectious Disease Associates Of Orange County, Inc.'s specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Is Infectious Disease Associates Of Orange County, Inc. enrolled in Medicare?

Yes. Infectious Disease Associates Of Orange County, Inc. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Infectious Disease Associates Of Orange County, Inc.?

According to the CMS Revalidation Reassignment List (October 2026 release), 9 clinicians in 2 Medicare specialties reassign their Medicare billing to Infectious Disease Associates Of Orange County, Inc.. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. The largest specialties are Infectious Disease (7) and Nurse Practitioner (2). Of these, 2 practice at this address and 6 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Infectious Disease Associates Of Orange County, Inc. was last updated on August 14, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 14 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.