A 38-year-old woman from Bolivia is seen for palpitations and mild exertional dyspnea. The electrocardiogram shows a right bundle branch block with left anterior fascicular block.
To a cardiologist in Santa Cruz, that combination in a patient from a rural endemic area is a specific pattern with a specific name, and the next step is obvious.
To a cardiologist in the United States who has never encountered it, the tracing is an unusual conduction abnormality in a young woman, and the workup proceeds down an entirely different path.
She has Chagas cardiomyopathy. There are approximately 300,000 people with Chagas disease in the United States.
And somewhere in the same metropolitan area, quite possibly in the same hospital, is a physician who trained in Bolivia, Argentina, or Brazil, who has seen dozens of these, and whose entire directory listing says "internal medicine."
The scale of what is being missed
The evidence on imported disease recognition in high-income countries is stark and consistent.
Chagas disease. A health systems analysis published in PLoS Neglected Tropical Diseases found that of roughly 300,000 US cases, CDC released 422 courses of treatment between 2007 and 2013, meaning fewer than one percent were treated. The analysis described a single Center of Excellence and physicians "working in isolation using ad hoc systems."
The knowledge gap among clinicians who encounter these patients is documented directly:
- 68.8 percent of surveyed US obstetrician-gynecologists had very limited Chagas knowledge, and 77.9 percent had never considered the diagnosis in patients from endemic countries. This matters specifically because Chagas can be transmitted congenitally, making obstetric recognition a prevention opportunity.
- In Appalachian Ohio, more than 80 percent of 105 surveyed physicians reported limited knowledge and 50 percent had never considered testing.
Imported malaria. A 2025 study found imported malaria misdiagnosed at first visit in 46.1 percent of sub-Saharan migrants in one cohort, with misdiagnosis carrying an adjusted odds ratio of 2.23 for severe disease. In US pediatric imported malaria between 2016 and 2023, 26 percent had delayed diagnosis.
Malaria is not obscure. Every physician learns it. And nearly half of one cohort was misdiagnosed at first presentation, with measurably worse outcomes as a result.
Strongyloidiasis. Spain's +REDIVI network logged 1,245 imported cases across 22 centers between 2009 and 2017, with 66.9 percent in immigrants, and stool microscopy positive in only 21.9 percent, meaning the standard test most clinicians would order misses roughly four in five cases.
This one carries a specific and preventable catastrophe: hyperinfection syndrome following corticosteroid administration, which is frequently fatal and entirely preventable by screening before immunosuppression. In an era of widespread steroid and biologic use, that is a recurring, avoidable death.
Why this is a routing problem rather than a training problem
The instinctive response is educational: teach clinicians more tropical medicine.
That response is well intentioned and, at the scale required, unrealistic. A primary care physician cannot maintain working expertise across the full range of conditions their patient population might import. The number of relevant diseases is large, the individual prevalence is low, and the pattern recognition that matters is built by seeing many cases rather than by reading about them.
What the physician actually needs is not to know the answer. It is to be able to reach someone who does, quickly, when a patient's history raises the possibility.
And here is the fact that makes this a genuine coordination failure rather than a resource gap.
The expertise is already in the country.
There are 606,000 foreign-trained doctors in OECD countries, representing 18.4 percent of all doctors and up 62 percent since 2010. In the United States, about one in four physicians is an international medical graduate.
Many of them trained in the exact regions these diseases come from. They saw Chagas in medical school. They managed malaria as residents. They know what strongyloidiasis looks like before the eosinophilia and what to do about it before the steroids.
And not one directory in any receiving country has a field for it.
The indexing failure, precisely stated
Consider what is recorded about an internal medicine physician who completed medical school and residency in Lagos before completing US training.
Recorded: medical school, graduation year, residency, board certification, current employer, specialty.
Not recorded: that she managed several hundred cases of falciparum malaria, that she can recognize the clinical pattern of typhoid before the culture returns, that she has seen more schistosomiasis than any infectious disease physician in her state.
Her credentials record where she trained. They record nothing about what she saw there.
This is the credential-expertise gap in one of its sharpest forms. The relevant expertise is real, deep, verifiable in principle, and structurally invisible.
The result is what the Chagas analysis described: physicians working in isolation with ad hoc systems, while the person who could help works two floors away, mis-labeled as an internist.
What clinicians do instead
The current workflow when a clinician suspects something imported:
Call the infectious disease fellow, who may have limited exposure themselves, since US infectious disease training is weighted toward hospital-acquired infection, HIV, and antimicrobial stewardship rather than tropical medicine.
Email the CDC parasitic diseases inquiry line, which is a genuine and valuable resource, and operates on a timescale suited to consultation rather than a clinical decision this afternoon.
Search society lists or surveillance networks, which identify academic centers rather than reachable individuals.
Or ask the colleague from Brazil, if you happen to know they exist.
That last one works extremely well and depends entirely on whether the physician happens to have a personal relationship with a colleague from the right region.
Which means the quality of care for imported disease is determined by the social composition of the treating physician's personal network.
Why this is intensifying
Several trends are converging, all pointing the same direction.
Migration is at high levels globally, with substantial movements driven by conflict and economic pressure, distributing endemic-region patients into health systems with no experience of their conditions.
Vector ranges are expanding with climate change, meaning some conditions are becoming locally acquired rather than purely imported in areas that have never seen them.
International travel has recovered and grown, and travelers visiting friends and relatives in endemic regions are a well-documented high-risk group who frequently present to clinicians with no travel medicine background.
Immunosuppression is more common, with widespread use of steroids and biologics, which converts several chronic parasitic infections from indolent to lethal.
And the diaspora physician supply is at an all-time high, up 62 percent since 2010, which means the resource is growing at the same time as the need.
The gap between available expertise and reachable expertise has never been wider.
What would actually work
Index disease exposure, not just training location. A structured field capturing the conditions a physician has meaningful clinical experience with, including from practice abroad, dated and peer-corroborable. This is straightforward to collect and exists nowhere.
Make it queryable by presentation. The useful query is not "who is an infectious disease specialist" but "who has managed Chagas cardiomyopathy" or "who has seen this radiographic pattern in a patient from this region."
Include the cross-border hop. For the hardest cases, connecting a domestic physician to a verified physician still practising in the endemic region is enormously valuable and currently happens only through personal WhatsApp relationships, with all the verification and consent problems that entails.
Recognize the professional value to the IMG physician. A physician whose foreign clinical experience is currently invisible gains professional standing from having it recognized and sought. This is one of the rare interventions where the person being asked to contribute also benefits directly.
And keep the guardrails clear. De-identified questions, general educational framing, consent for anything patient-specific, and clinical responsibility remaining unambiguously with the treating clinician.
What you can do now
If you practise in an immigrant-receiving area
Take a real travel and origin history, routinely. Where the patient was born, where they have lived, when they last visited, and for how long. This single habit surfaces most of what is missed, and it is frequently omitted entirely.
Learn the small number of high-yield patterns. Not tropical medicine broadly. The specific ones with catastrophic and preventable failure modes: strongyloidiasis before immunosuppression, malaria in a febrile returning traveler regardless of prophylaxis, Chagas in a patient from an endemic area with new conduction disease.
Find out who in your institution trained abroad, and where. This takes one conversation with your department administrator and produces a resource nothing else can. Then ask them, directly, whether they would be willing to be asked.
Use CDC and equivalent national consultation services. They exist, they are staffed by genuine experts, and they are underused by clinicians who do not know they are available.
If you trained abroad
Say what you have seen. Your colleagues do not know, because nothing records it and asking feels intrusive. Telling your department that you managed hundreds of cases of a condition they will encounter twice a decade is professionally valuable to you and clinically valuable to them.
Offer explicitly. "If you see a patient from West Africa with fever, call me" is a sentence that will save someone a delayed diagnosis, and nobody will think to ask you unaided.
Maintain your home-country relationships deliberately. They are a professional asset with real clinical value, and they decay without attention.
If you lead a department or a health system
Map your own workforce's international training and experience. You almost certainly employ substantial expertise in conditions your patient population presents with, and you have no record of it. This is a spreadsheet exercise with a real clinical return.
Build the referral pathway before you need it. Which physician in your system takes questions about imported disease? If the answer is nobody in particular, that is a gap with documented consequences including a 46.1 percent first-visit misdiagnosis rate for imported malaria in one cohort.
Screen for strongyloidiasis before immunosuppression in at-risk patients. This is an established recommendation, it is inconsistently implemented, and the failure mode is a preventable death.
Frequently asked questions
How common is Chagas disease in the United States? Approximately 300,000 people are estimated to have Chagas disease in the US. A health systems analysis found CDC released 422 courses of treatment between 2007 and 2013, meaning fewer than one percent of estimated cases were treated during that period, with care concentrated at a single Center of Excellence and physicians described as working in isolation using ad hoc systems.
Do US clinicians recognize imported diseases? Frequently not. Surveys found 68.8 percent of US obstetrician-gynecologists had very limited Chagas knowledge with 77.9 percent never having considered the diagnosis in patients from endemic countries, and more than 80 percent of surveyed physicians in one Appalachian Ohio study reported limited knowledge with half never considering testing.
How often is imported malaria misdiagnosed? In one 2025 study of sub-Saharan migrants, imported malaria was misdiagnosed at first visit in 46.1 percent of cases, with misdiagnosis associated with an adjusted odds ratio of 2.23 for severe malaria. US pediatric data from 2016 to 2023 found 26 percent with delayed diagnosis.
Why does strongyloidiasis matter before starting steroids? Because chronic strongyloidiasis can progress to hyperinfection syndrome following corticosteroid administration, which is frequently fatal and preventable through screening. Detection is difficult with standard testing: in a Spanish network of 1,245 imported cases, stool microscopy was positive in only 21.9 percent, meaning serology is generally required.
Is this a training problem or a routing problem? Substantially a routing problem. No generalist can maintain working expertise across the full range of conditions a diverse patient population might import. The relevant expertise already exists in high-income countries, held by the 606,000 foreign-trained doctors in OECD countries, whose credentials record where they trained and nothing about what they saw there.
How can a clinician get help with a suspected imported disease? National consultation services including CDC's parasitic diseases inquiry line are available and underused. Within an institution, identifying colleagues who trained in relevant regions is frequently the fastest route, and taking a systematic birthplace and travel history is the step that surfaces the possibility in the first place.
The bottom line
A woman from Bolivia with a specific conduction abnormality sits in an American cardiology clinic. The pattern is well recognized by physicians trained in her home region and unfamiliar to the one examining her.
Somewhere nearby, quite possibly in the same building, is a physician who would recognize it immediately, whose listing says "internal medicine," and whose years of clinical experience with the condition appear in no record anywhere.
Fewer than one percent of estimated US Chagas cases were treated over a seven-year period. Nearly half of imported malaria in one cohort was misdiagnosed at first presentation. A parasitic infection that becomes lethal under steroids goes undetected because the standard test misses four in five cases and few clinicians know to order the right one.
None of this reflects a shortage of knowledge in the country. There are 606,000 foreign-trained physicians in wealthy countries, and their numbers are growing quickly.
The knowledge arrived with them, and nobody wrote down that it was here.
Part of a series on the missing professional infrastructure of healthcare. Previously: Reference Fatigue
Evidence note: Chagas treatment and health systems findings come from PLoS Neglected Tropical Diseases (2015). Clinician knowledge surveys come from Emerging Infectious Diseases (2010) and the Journal of Racial and Ethnic Health Disparities (2017), the latter a small regional sample. Imported malaria misdiagnosis figures come from Infection (2025) and Pediatrics (2026). Strongyloidiasis network data comes from the +REDIVI network published in PLoS Neglected Tropical Diseases (2019). Physician migration figures come from the OECD International Migration Outlook 2025. Prevalence estimates for imported conditions vary by source and methodology. Nothing in this article is clinical guidance for any individual patient.
