Travel-Related Diagnoses Among U.S. Nonmigrant Travelers or Migrants Presenting to U.S. GeoSentinel Sites — GeoSentinel Network, 2012–2021
Results
During 2012–2021, a total of 198,120 unique patients were evaluated at GeoSentinel sites globally and included in GeoSentinel’s database (Figure 3). Of these, 177,703 patients received at least one confirmed or probable travel-related diagnosis, of which 18,336 were reported from 20 GeoSentinel sites in the United States. Of the 17,538 patients evaluated by a clinician after travel, 17,389 were migrants or returning U.S. nonmigrant travelers to the United States, accounting for 25,973 travel-related diagnoses. The remaining 149 patients were non-U.S. residents and were excluded from the analysis. The results of migrants and returning nonmigrant travelers are reported separately.
Migrants
Patient Demographics
Of the 17,389 patients who were included in this analysis, 7,530 (43.3%) were recent migrants to the United States; <1% of patients were expatriates. Of 7,527 migrants, 47.4% were female (Table 1). The median age was 28.5 years (range = <19 years to 93 years), and the largest proportion of migrants was aged 19–39 years (35.9%). Of 4,672 patients with information available, 88.8% did not receive pretravel health information. Of 2,867 patients with information available on severity, a majority (89.8%) were seen as outpatients, 9.7% were seen in an inpatient ward, and <1% were seen in an ICU.
Diagnoses
Of the 13,986 travel-related diagnoses among migrants, the most frequent were vitamin D deficiency (20.2%), Blastocystis (10.9%), latent tuberculosis (10.3%), strongyloidiasis (6.7%), and eosinophilia (5.8%) (Table 2). A total of 43% of diagnoses fell into eight infectious or travel-related syndrome groupings including “other” (18.7%), gastrointestinal (15.7%), dermatological (2.0%), neurologic (1.9%), genitourinary (1.6%), febrile (1.5%), respiratory (1.5%), and musculoskeletal (<1%). No deaths or animal bites or scratches were reported (Table 3).
Of the 2,614 diagnoses in the “other” grouping (Table 3), the most frequent were latent tuberculosis (55.2%), eosinophilia (30.8%), Chagas disease (3.8%), posttraumatic stress disorder (3.6%), and depression (2.9%). Of the 2,202 diagnoses in the gastrointestinal grouping, the most frequent were simple intestinal strongyloidiasis (41.6%), giardiasis (18.9%), Helicobacter pylori infection (8.4%), dientamoebiasis (6.9%), and schistosomiasis (6.5%). Of the 275 diagnoses in the dermatological grouping, the most frequent were fungal infection (42.6%), insect bite/sting (10.9%), rash of unknown etiology (10.2%), cutaneous leishmaniasis (5.8%), and leprosy (4.4%). Of the 263 diagnoses in the neurologic grouping, the most frequent were neurocysticercosis (76.8%), headache (16.4%), ataxia (1.5%), central nervous system tuberculosis (1.5%), and tuberculosis meningitis (1.1%). Of the 229 diagnoses in the genitourinary grouping, the most frequent were schistosomiasis (27.5%), chlamydia (15.3%), syphilis (11.4%), urinary tract infection (10.9%), and HIV (10.0%).
Among the 212 diagnoses in the febrile grouping (Table 3), the most frequent were malaria (25.5%), other extrapulmonary tuberculosis (13.2%), toxoplasmosis (8.0%), tuberculosis lymphadenitis (6.6%), and disseminated tuberculosis (5.2%). Malaria was diagnosed in 54 (<1%) migrants, and 88.5% did not receive pretravel health information (information available for 26 migrants). Of all species of malaria, Plasmodium falciparum was diagnosed most frequently (77.4%).
Among the 204 diagnoses in the respiratory grouping (Table 3), the most frequent was pulmonary tuberculosis (70.6%), which accounted for 68.9% of all active tuberculosis diagnoses; only 1% of migrants received a diagnosis of active tuberculosis disease. The remaining frequent diagnoses in the respiratory grouping were acute otitis media (4.9%), atypical pneumonia (3.4%), otitis externa (2.9%), and unspecified lobar pneumonia (2.9%). Of the 131 diagnoses in the musculoskeletal grouping, the most frequent were arthralgia (48.1%), trauma or injury (43.5%), osteomyelitis (1.5%), knee pain (1.5%), and sprain (1.5%).
Diagnostic Characteristics Before November 16, 2018
Among the 2,892 diagnoses with information available (Table 4), the five most frequent regions of exposure were Sub-Saharan Africa (22.7%), the Caribbean (21.3%), Central America (13.4%), South East Asia (13.1%), and South Central Asia (9.2%). Among the 2,554 diagnoses with information available, the most frequent countries of exposure were Dominican Republic (7.9%), Thailand (6.5%), Haiti (6.2%), Ecuador (4.8%), and Myanmar (4.3%). Of 46 migrants with a malaria diagnosis, 89.3% were exposed in Sub-Saharan Africa (information available for 28 migrants).
Diagnostic Characteristics After November 16, 2018
Among the 2,012 diagnoses with information available (Table 4), the five most frequent regions of exposure were Central America (27.6%), Sub-Saharan Africa (26.2%), South East Asia (16.9%), the Caribbean (8.4%), and South America (7.0%). Among the 1,575 diagnoses with information available, the most frequent countries of exposure were El Salvador (11.2%), Thailand (10.7%), Honduras (9.1%), Guatemala (7.6%), and Dominican Republic (5.9%). Of seven migrants with a malaria diagnosis, all were exposed in Sub-Saharan Africa (information available for seven migrants).
Returning Nonmigrant Travelers
Patient Demographics
Among the 9,859 nonmigrant travelers returning to the United States, 55.7% were female and 75.3% were born in the United States. The median age was 37 years (range = <19 years to 96 years), and the largest proportion of nonmigrant travelers was aged 19–39 years (44.1%). Among the 8,967 patients with information available, 65.6% did not receive pretravel health information. Among the 5,884 patients with information available on severity, a majority (90.6%) were seen as outpatients, 8.4% were seen in an inpatient ward, and <1% were seen in an ICU. Approximately 1% of patients were expatriates, and 89.4% were U.S. citizens.
Diagnoses
Of the 11,987 travel-related diagnoses of returning U.S. nonmigrant travelers (Table 3), 90.7% of diagnoses fell into nine infectious or travel-related syndrome groupings, including gastrointestinal (43.2%), febrile (16.7%), respiratory (13.0%), dermatological (8.9%), “other” (4.1%), animal bites or scratches (1.3%), genitourinary (1.4%), musculoskeletal (1.2%), and neurologic (<1%). The most frequent diagnoses (Table 2) were acute diarrhea (16.9%), viral syndrome (4.9%), irritable bowel syndrome (4.1%), campylobacteriosis (3.1%), and malaria (3.5%). Four deaths were reported, of which two were patients who received a diagnosis of severe P. falciparum malaria. Of the remaining two patients, one received a diagnosis of COVID-19 and the other received a diagnosis of acute unspecified hepatitis with renal failure.
Among the 5,173 diagnoses in the gastrointestinal grouping (Table 3), the most frequent were acute diarrhea (39.3%), irritable bowel syndrome (9.5%), campylobacteriosis (7.2%), giardiasis (5.5%), and chronic diarrhea (5.2%). Among the 2,001 diagnoses in the febrile grouping, the most frequent were viral syndrome (29.0%), malaria (21.0%), dengue (13.7%), chikungunya (6.4%), and unspecified febrile illness (5.0%). Among the 421 nonmigrant travelers with malaria of any species diagnosed, 80.8% had P. falciparum.
Among the 1,554 diagnoses in the respiratory grouping (Table 3), the most frequent were influenza-like illness (16.5%), upper respiratory tract infection (14.9%), acute bronchitis (11.9%), acute sinusitis (9.1%), and unspecified lobar pneumonia (8.4%). Among the 1,071 diagnoses in the dermatological grouping, the most frequent were insect or arthropod bite or sting (31.3%), rash of unknown etiology (8.8%), dermatitis (7.9%), skin and soft tissue infection (e.g., erysipelas, cellulitis, or gangrene [7.4%]), and superficial skin and soft tissue infection (6.0%). Among the 487 diagnoses in the “other” grouping, the most frequent were dehydration (18.7%), jet lag (17.9%), eosinophilia (11.7%), latent tuberculosis (8.8%), and anxiety disorder (7.6%).
Among the 173 diagnoses in the genitourinary grouping (Table 3), the most frequent were urinary tract infection (33.0%), schistosomiasis (11.6%), gonorrhea (9.3%), pyelonephritis (8.7%), and genital chlamydia (8.1%). Among the 142 diagnoses in the musculoskeletal grouping, the most frequent were arthralgia (19.7%), fracture (17.6%), myalgia (10.6%), trauma or injury (9.9%), and contusion (7.8%). Among the 105 diagnoses in the neurologic grouping, the most frequent were headache (26.7%), vertigo (12.4%), acute mountain sickness (10.5%), neurocysticercosis (9.5%), and dizziness (8.6%). Among the 153 diagnoses of bites or scratches, the most frequent were dog bite (50.3%), monkey bite (18.3%), other animal bite (6.5%), monkey exposure (5.9%), and dog exposure (3.9%).
Diagnostic Characteristics Before November 16, 2018
Among the 9,919 diagnoses, 6,518 had information regarding travel reason (Table 5). The most frequent reasons for travel were tourism (44.8%), VFR (22.0%), and business (13.4%). Among the 6,296 diagnoses with information available, the five most frequent regions of exposure were Central America (19.2%), Sub-Saharan Africa (17.7%), the Caribbean (13.0%), South East Asia (10.4%), and South America (9.4%). Among 5,920 diagnoses with information available, the most frequent countries of exposure were Mexico (12.5%), India (7.2%), Dominican Republic (5.3%), China (3.3%), and Costa Rica (3.0%).
Of 300 nonmigrant travelers with malaria, 70.3% were VFRs (information available for 232 nonmigrant travelers), and 88.6% were exposed in Sub-Saharan Africa. Of 163 VFRs with malaria, 70.2% did not receive pretravel health information (information available for 141 nonmigrant travelers), and 88.3% did not take malaria chemoprophylaxis (information available for 103 nonmigrant travelers).
Diagnostic Characteristics After November 16, 2018
Information regarding travel reason and exposure region was available for all 2,068 diagnoses (Table 5). The most frequent reasons for travel were tourism (53.6%), VFR (21.4%), business (12.3%), and missionary (6.2%). The five most frequent regions of exposure were Sub-Saharan Africa (25.5%), Central America (17.3%), South East Asia (11.2%), the Caribbean (10.9%), and South Central Asia (9.0%). Among the 1,894 diagnoses with information available, the most frequent countries of exposure were Mexico (13.2%), India (5.0%), Dominican Republic (4.2%), Philippines (3.0%), and Ethiopia (3.0%).
Of 121 nonmigrant travelers with malaria, 57.9% were VFRs and 95.9% were exposed in Sub-Saharan Africa. Of 70 VFRs with malaria, 83.3% did not receive pretravel health information (information available for 54 nonmigrant travelers), and none took malaria chemoprophylaxis (information available for three nonmigrant travelers).
