Surgery Abroad Infection Risk: CDC Screens You for 6 Months

Spend a night in a hospital outside the United States, then turn up at a US hospital within six months, and the guidance says you should be swabbed for a drug-resistant gut bacterium. Not asked about it. Swabbed.

That instruction is published, current, and addressed entirely to clinicians. It sits in the CDC Yellow Book's chapter on medical tourism, written for health care providers, and it says nothing about who tells the patient. The lab test behind it costs the hospital nothing.

What the guidance actually says

The 2026 edition of the CDC Yellow Book puts it in a single sentence. The chapter is on medical tourism, written by Rhett J. Stoney and Laura Leidel, and was last reviewed on 23 April 2025.

The organism it names is carbapenem-resistant Enterobacterales (CRE), a group of gut bacteria that resist the carbapenem antibiotics doctors hold back for serious infections. "Patients who have had an overnight stay in a healthcare facility outside the United States within 6 months of presentation should be screened for CRE," the chapter says.¹

The same chapter explains why travel is the trigger. Some highly resistant bacterial and fungal pathogens, it says, "appear to be more common in some countries where U.S. residents travel for medical tourism".¹

A separate CDC publication states the rule in more physical terms. A 2019 report in Morbidity and Mortality Weekly Report sets the same six-month boundary. Any patient with an overnight stay in a health care facility outside the United States in the preceding six months "should undergo rectal screening for carbapenemases on admission to a U.S. health care facility".² Two independent CDC publications, seven years apart, give the same window.

The tests are free to the facility. The CDC's Antimicrobial Resistance Laboratory Network says of its colonization screening for carbapenemase-producing organisms: "Screening test is free, including shipping."³ Results come back within two business days, and a facility requests it through its state public health laboratory.³

For Candida auris, a drug-resistant yeast, the screening is different again. The CDC recommends screening patients with current or previous health care encounters at facilities outside the United States. The sample is "a composite swab of the patient's bilateral axilla (i.e., armpit) and groin".⁴ That recommendation, updated on 15 December 2025, sets no time window at all.⁴

The outbreak the guidance was written around

The Yellow Book's warning is not hypothetical, though the documented case involves a different organism. Between 1 August 2018 and 31 December 2019, CDC investigators identified 44 cases across 19 states of an extensively drug-resistant Pseudomonas aeruginosa carrying a Verona integron-encoded metallo-beta-lactamase.⁵

The cases pointed at one place. Of the 38 case-patients with usable information, 27 reported surgery at a single Tijuana facility, and 31 of 35 who named a surgeon named the same one.⁵ Sixteen of the 38 were hospitalised back in the United States. One died in hospital nine days after a sleeve gastrectomy.⁵

Mexico's federal health-risk commission assessed the facility and found "multiple lapses, including poor hand hygiene practices, incomplete clinical records, and lack of chemical or biologic indicators to ensure medical equipment and device sterility".⁵

Note what found these patients. Resistant Pseudomonas isolates are routinely sent from clinical laboratories to the same Antibiotic Resistance Laboratory Network that offers the free screening.⁵ The surveillance system detected the cluster; the patients did not report it.

2,882 clinical cases6,197 clinical cases

20222024

Vertical scale spans 2,882 clinical cases to 6,197 clinical cases; it does not start at zero.

Clinical cases reported to the CDC by state and jurisdictional health departments, all sources of exposure combined. These are not medical-tourism-associated cases: the same surveillance summary reports that most recent cases were acquired in US healthcare settings. Screening cases, of which there were 27,853 over the period, are counted separately and are not plotted.

Source: note 6

Show the numbers

Item	Value
2022	2,882 clinical cases
2023	4,428 clinical cases
2024	6,197 clinical cases

What the headline numbers leave out

Pseudomonas is not CRE. The six-month rule is about carbapenem-resistant Enterobacterales. The Mexico outbreak was Pseudomonas aeruginosa, and the 2019 report notes carbapenemases cause carbapenem resistance less often in that organism than in Enterobacterales.² They are related problems, not the same one.

The trend now runs the other way. A CDC surveillance summary published on 2 July 2026 reported 13,507 Candida auris clinical cases in the United States during 2022 to 2024, rising from 2,882 in 2022 to 6,197 in 2024. Its own assessment: "Early cases were usually associated with health care exposure abroad, whereas most of the recent cases were acquired in U.S. health care settings."⁶ Care abroad is a screening criterion, not the main source.

Screening is not infection. A positive colonization screen means the organism is present, not that you are ill. The guidance exists to stop transmission inside the receiving hospital.

The window is a precaution, not an observed interval. In the Mexico outbreak the median time from surgery to a positive specimen was 12 days, with a range of 3 to 40 days.⁵ The six-month window is far wider, and nothing in these sources explains how it was set.

It is one country's guidance. Everything here is the CDC, addressed to US facilities. Nothing in this article establishes what any other country's hospitals do on admission.

How to use this

Volunteer the information. The guidance turns on whether the admitting facility knows you stayed overnight in a hospital abroad in the last six months. The 2019 CDC report puts that duty on the patient. People who become ill after medical treatment abroad "should report any hospitalizations or other medical care to their medical providers".² A discharge summary and the facility's name are what make that usable.

Keep the paperwork for six months, not six days. Write down the hospital, the city, the dates of any overnight stay and the procedure. If you are admitted in the United States inside that window, say so at the desk. The screen a clinician may then order is a rectal swab, and it costs the hospital nothing.

Footnotes

1. https://www.cdc.gov/yellow-book/hcp/health-care-abroad/medical-tourism.html — Rhett J. Stoney and Laura Leidel, "Medical Tourism", CDC Yellow Book 2026, Centers for Disease Control and Prevention (last reviewed 23 April 2025). Accessed Sep 23, 2026. ↩ ↩²

2. https://www.cdc.gov/mmwr/volumes/68/wr/mm6820a4.htm — Ian Kracalik and others, "Notes from the Field: Verona Integron-Encoded Metallo-β-Lactamase–Producing Carbapenem-Resistant Pseudomonas aeruginosa Infections in U.S. Residents Associated with Invasive Medical Procedures in Mexico, 2015–2018", Morbidity and Mortality Weekly Report 68(20), Centers for Disease Control and Prevention (published 24 May 2019). Accessed Sep 23, 2026. ↩ ↩² ↩³

3. https://www.cdc.gov/antimicrobial-resistance-laboratory-networks/php/about/testing-services.html — Centers for Disease Control and Prevention, "Antimicrobial Resistance Laboratory Network Testing" (last updated 3 June 2025). Accessed Sep 23, 2026. ↩ ↩²

4. https://www.cdc.gov/candida-auris/hcp/screening-hcp/ — Centers for Disease Control and Prevention, "Screening Recommendations for Healthcare Facilities", Candida auris (last updated 15 December 2025). Accessed Sep 23, 2026. ↩ ↩²

5. https://wwwnc.cdc.gov/eid/article/28/1/21-1880_article — Ian Kracalik and others, "Extensively Drug-Resistant Carbapenemase-Producing Pseudomonas aeruginosa and Medical Tourism from the United States to Mexico, 2018-2019", Emerging Infectious Diseases 28(1), Centers for Disease Control and Prevention (January 2022). Accessed Sep 23, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

6. https://www.cdc.gov/mmwr/volumes/75/ss/ss7504a1.htm — Jeremy A. W. Gold and others, "Surveillance for Candida auris — United States, 2022-2024", Morbidity and Mortality Weekly Report Surveillance Summaries 75(4), Centers for Disease Control and Prevention (published 2 July 2026). Accessed Sep 23, 2026. ↩

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