Orange County Health Care Agency surveillance for Bundibugyo virus disease (BVD) remains active following the May 22, 2026 CAHAN clinician alert. As of the latest refresh (June 6, 2026), no cases of BVD have been reported in the United States or California. CDC continues to assess the immediate risk to the general US public as low. No new local, state, or federal advisories contradicting prior guidance have been identified in this update cycle. The candidate item pool reviewed for this refresh contained no items relevant to this situation.

On May 15, 2026, the Democratic Republic of the Congo and the Republic of Uganda officially declared outbreaks of Bundibugyo virus disease. As of May 18 (per the May 22 CAHAN), DRC had reported 10 confirmed cases, 336 suspected cases, and 88 suspected deaths. Uganda reported two cases in Kampala — travelers from DRC — including one death. On May 17, a U.S. citizen in DRC with documented high-risk exposures tested positive; that individual and six other U.S. citizens with high-risk exposures were evacuated to a treatment facility in Germany. WHO determined the situation to constitute a Public Health Emergency of International Concern (PHEIC).

By approximately May 25, 2026, the DRC outbreak had escalated significantly beyond the May 18 snapshot. Reports indicated over 900 suspected cases and more than 220 suspected deaths in DRC, with the epicenter in Ituri Province. Uganda reported additional cases (total approximately 7), still linked to DRC travel. WHO maintained the PHEIC and described national risk in DRC as very high, with the expectation that the situation "will get worse before it gets better." No new US or California cases were reported.

The May 22 CAHAN, issued jointly by CDPH and OC Health following the May 19 CDC HAN Advisory, directs clinicians to suspect BVD in any patient who: (1) traveled to DRC or Uganda in the prior 21 days, (2) presents with compatible symptoms (fever, headache, myalgia, fatigue, anorexia, gastrointestinal symptoms, or unexplained bleeding), and (3) reports relevant epidemiologic risk factors. Clinicians are instructed to immediately implement Ebola-specific infection control precautions and notify OC Health. Travelers with recent exposure history who develop symptoms are advised to contact their local health department rather than presenting directly to a clinical setting. See the OC Health CAHAN page for full guidance.

John Wayne Airport (SNA) serves as the primary international gateway for north and central OC. The 21-day incubation window means travelers who transited through affected regions could present within OC weeks after arrival. The SNA catchment surveillance zone and I-405/SR-55/SR-5 corridor populations remain the focus of CAHAN clinician outreach.

Key indicators for escalation: any confirmed or suspected US case linked to this outbreak; updated WHO/CDC case counts showing geographic spread; changes to CDC travel advisories for DRC or Uganda; or any OC Health notification of a person under investigation (PUI).