This work is written by (a) US Government employee(s) and is in the public domain in the US. Measles remains a risk for travelers, with 94 measles diagnoses reported to the GeoSentinel network from 2000 to 2014, two-thirds since 2010. Asia was the most common exposure region, then Africa and Europe. Efforts to reduce travel-associated measles should target all vaccine-eligible travelers, including catch-up vaccination of susceptible adults.

Background.  The 2014-2015 Ebola epidemic in West Africa had global impact beyond the primarily affected countries of Guinea, Liberia, and Sierra Leone. Other countries, including the United States, encountered numerous patients who arrived from highly affected countries with fever or other signs or symptoms consistent with Ebola virus disease (EVD). Methods.  We describe our experience evaluating 25 travelers who met the US Centers for Disease Control and Prevention case definition for a person under investigation (PUI) for EVD from July 20, 2014 to January 28, 2015. All patients were triaged and evaluated under the guidance of institutional protocols to the emergency department, outpatient tropical medicine clinic, or Emory's Ebola treatment unit. Strict attention to infection control and early involvement of public health authorities guided the safe evaluation of these patients. Results.  None were diagnosed with EVD. Respiratory illnesses were common, and 8 (32%) PUI were confirmed to have influenza. Four patients (16%) were diagnosed with potentially life-threatening infections or conditions, including 3 with Plasmodium falciparum malaria and 1 with diabetic ketoacidosis. Conclusions.  In addition to preparing for potential patients with EVD, Ebola assessment centers should consider other life-threatening conditions requiring urgent treatment, and travelers to affected countries should be strongly advised to seek pretravel counseling. Furthermore, attention to infection control in all aspects of PUI evaluation is paramount and has presented unique challenges. Lessons learned from our evaluation of potential patients with EVD can help inform preparations for future outbreaks of highly pathogenic communicable diseases.

BACKGROUND: US residents make 60 million international trips annually. Family practice providers need to be aware of travel-associated diseases affecting this growing mobile population. OBJECTIVE: To describe demographics, travel characteristics and clinical diagnoses of US residents who present ill after international travel. METHODS: Descriptive analysis of travel-associated morbidity and mortality among US travellers seeking care at 1 of the 22 US practices and clinics participating in the GeoSentinel Global Surveillance Network from January 2000 to December 2012. RESULTS: Of the 9624 ill US travellers included in the analysis, 3656 (38%) were tourist travellers, 2379 (25%) missionary/volunteer/research/aid workers (MVRA), 1580 (16%) travellers visiting friends and relatives (VFRs), 1394 (15%) business travellers and 593 (6%) student travellers. Median (interquartile range) travel duration was 20 days (10-60 days). Pre-travel advice was sought by 45%. Hospitalization was required by 7%. Compared with other groups of travellers, ill MVRA travellers returned from longer trips (median duration 61 days), while VFR travellers disproportionately required higher rates of inpatient care (24%) and less frequently had received pre-travel medical advice (20%). Illnesses of the gastrointestinal tract were the most common (58%), followed by systemic febrile illnesses (18%) and dermatologic disorders (17%). Three deaths were reported. Diagnoses varied according to the purpose of travel and region of exposure. CONCLUSIONS: Returning ill US international travellers present with a broad spectrum of travel-associated diseases. Destination and reason for travel may help primary health care providers to generate an accurate differential diagnosis for the most common disorders and for those that may be life-threatening.

Background The failure to consider travel-related diagnoses, the lack of diagnostic capacity for specialized laboratory testing, and the declining number of autopsies may affect the diagnosis and management of travel-related infections. Pre- and post-mortem pathology can help determine causes of illness and death in international travelers. Methods We conducted a retrospective review of biopsy and autopsy specimens sent to the Infectious Diseases Pathology Branch laboratory (IDPBL) at the Centers for Disease Control and Prevention (CDC) for diagnostic testing from 1995 through 2015. Cases were included if the specimen submitted for diagnosis was from a traveler with prior international travel during the disease incubation period and the cause of illness or death was unknown at the time of specimen submission. Results Twenty-one travelers, six (29%) with biopsy specimens and 15 (71%) with autopsy specimens, met the inclusion criteria. Among the 15 travelers who underwent autopsies, the most common diagnoses were protozoal infections (7 travelers; 47%), including five malaria cases, followed by viral infections (6 travelers; 40%). Conclusions Biopsy or autopsy specimens can assist in diagnosing infectious diseases in travelers, especially from pathogens not endemic in the U.S. CDC's IDPBL provides a useful resource for clinicians considering infectious diseases in returned travelers.

Introduction: As international travel increases, travellers may be at increased risk of acquiring infectious diseases not endemic in their home countries. Many journal articles and reference books related to travel medicine cite that between 22-64% of international travellers become ill during or after travel; however, this information is minimal, outdated and limited by poor generalizability. We aim to provide a current and more accurate estimate of the proportion of international travellers who acquire a travel-related illness.Methods: We identified studies via PubMed or travel medicine experts, published between January 1, 1976-December 31, 2016 that included the number of international travellers acquiring a travel-related illness. We excluded studies that focused on a single disease or did not determine a rate based on the total number of travellers. We abstracted information on traveller demographics, trip specifics, study enrollment and follow-up and number of ill travellers and their illnesses.Results: Of 743 studies, nine met the inclusion criteria. The data sources were from North America (four studies) and Europe (five studies). Most travellers were tourists, the most frequent destination regions were Asia and Africa, and the median trip duration ranged from 8-21 days. Six studies enrolled participants at the travellers' pre-travel consultation. All studies collected data through either extraction from the medical record, weekly diaries, or pre- and post-travel questionnaires. Data collection timeframes varied by study. Between 6-87% of travellers became ill across all studies. Four studies provided the best estimate: between 43-79% of travellers who frequently visited developing nations (e.g. India, Tanzania, and Kenya) became ill; travellers most frequently reported diarrhoea.Conclusion: This is the most comprehensive assessment available on the proportion of international travellers that develop a travel-related illness. Additional cohort studies would provide needed data to more precisely determine the rates of illness in international travellers.Keywords: International travel, travel, illness.

Background: Estimates of travel-related illness have focused predominantly on populations from highly developed countries visiting low- or middle-income countries, yet travel to and within high-income countries is very frequent. Despite being a top international tourist destination, few sources describe the spectrum of infectious diseases acquired among travellers to the USA. Methods: We performed a descriptive analysis summarizing demographic and travel characteristics, and clinical diagnoses among non-US-resident international travellers seen during or after travel to the USA at a GeoSentinel clinic from 1 January 1997 through 31 December 2016. Results: There were 1222 ill non-US-resident travellers with 1393 diagnoses recorded during the 20-year analysis period. Median age was 40 (range 0-86 years); 52% were female. Patients visited from 63 countries and territories, most commonly Canada (31%), Germany (14%), France (9%) and Japan (7%). Travellers presented with a range of illnesses; skin and soft tissue infections of unspecified aetiology were the most frequently reported during travel (29 diagnoses, 14% of during-travel diagnoses); arthropod bite/sting was the most frequently reported after travel (173 diagnoses, 15% after-travel diagnoses). Lyme disease was the most frequently reported arthropod-borne disease after travel (42, 4%). Nonspecific respiratory, gastrointestinal and systemic infections were also among the most frequently reported diagnoses overall. Low-frequency illnesses (<2% of cases) made up over half of diagnoses during travel and 41% of diagnoses after travel, including 13 cases of coccidioidomycosis and mosquito-borne infections like West Nile, dengue and Zika virus diseases. Conclusions: International travellers to the USA acquired a diverse array of mostly cosmopolitan infectious diseases, including nonspecific respiratory, gastrointestinal, dermatologic and systemic infections comparable to what has been reported among travellers to low- and middle-income countries. Clinicians should consider the specific health risks when preparing visitors to the USA and when evaluating and treating those who become ill.

Background: Through 2 international traveler-focused surveillance networks (GeoSentinel and TropNet), we identified and investigated a large outbreak of acute muscular sarcocystosis (AMS), a rarely reported zoonosis caused by a protozoan parasite of the genus Sarcocystis, associated with travel to Tioman Island, Malaysia, during 2011-2012. Methods: Clinicians reporting patients with suspected AMS to GeoSentinel submitted demographic, clinical, itinerary, and exposure data.We defined a probable case as travel to Tioman Island after 1 March 2011, eosinophilia (<5%), clinical or laboratory-supported myositis, and negative trichinellosis serology. Case confirmation required histologic observation of sarcocysts or isolation of Sarcocystis species DNA from muscle biopsy. Results: Sixty-eight patients met the case definition (62 probable and 6 confirmed). All but 2 resided in Europe; all were tourists and traveled mostly during the summer months. The most frequent symptoms reported were myalgia (100%), fatigue (91%), fever (82%), headache (59%), and arthralgia (29%); onset clustered during 2 distinct periods: "early" during the second and "late" during the sixth week after departure from the island. Blood eosinophilia and elevated serum creatinine phosphokinase (CPK) levels were observed beginning during the fifth week after departure. Sarcocystis nesbitti DNA was recovered from 1 muscle biopsy. Conclusions: Clinicians evaluating travelers returning ill from Malaysia with myalgia, with or without fever, should consider AMS, noting the apparent biphasic aspect of the disease, the later onset of elevated CPK and eosinophilia, and the possibility for relapses. The exact source of infection among travelers to Tioman Island remains unclear but needs to be determined to prevent future illnesses.

Hydatid cystic disease is a parasitic infestation caused by Echinococcus granulosus and commonly manifests as hepatic and pulmonary cysts. When feasible, based on cyst size and location, surgical resection is potentially curative. Post-surgical recurrence of disease is encountered in up to 25% of patients. Secondary peritoneal contamination is a recognized complication in 5-10% of cases. Disseminated disease is usually palliated using systemic anti-parasitic agents such as benzimidazoles, albendazole and mebendazole but worsening of disease post-systemic treatment is frequent in 14-25% of patients. In this report, we share our experience of a patient with long-standing, chronic disseminated hydatidosis and subsequent diagnosis of non-small cell lung cancer who manifested evidence of reduced activity of the echinococcal disease following institution of chemotherapy for his new diagnosis of lung cancer. There was significant reduction in the serum level of anti-echinococcal antibody titers in tandem with chemotherapy administration. There was also minimal but notable decrease in the size of the cysts on serial cross-sectional imaging obtained for monitoring cancer response to chemotherapy. This intriguing observation of a possible benefit of anticancer chemotherapy against echinococcal disease in this index case may provide new insights for therapeutic exploration in disseminated echinococcal disease.

Background: The early epidemiology of the 2022 monkeypox epidemic in non-endemic countries differs substantially from the epidemiology previously reported from endemic countries. We aimed to describe the epidemiological and clinical characteristics among individuals with confirmed cases of monkeypox infection. Methods: We descriptively analysed data for patients with confirmed monkeypox who were included in the GeoSentinel global clinical-care-based surveillance system between May 1 and July 1 2022, across 71 clinical sites in 29 countries. Data collected included demographics, travel history including mass gathering attendance, smallpox vaccination history, social history, sexual history, monkeypox exposure history, medical history, clinical presentation, physical examination, testing results, treatment, and outcomes. We did descriptive analyses of epidemiology and subanalyses of patients with and without HIV, patients with CD4 counts of less than 500 cells per mm3 or 500 cells per mm3 and higher, patients with one sexual partner or ten or more sexual partners, and patients with or without a previous smallpox vaccination. Findings: 226 cases were reported at 18 sites in 15 countries. Of 211 men for whom data were available, 208 (99%) were gay, bisexual, or men who have sex with men (MSM) with a median age of 37 years (range 18–68; IQR 32–43). Of 209 patients for whom HIV status was known, 92 (44%) men had HIV infection with a median CD4 count of 713 cells per mm3 (range 36–1659; IQR 500–885). Of 219 patients for whom data were available, 216 (99%) reported sexual or close intimate contact in the 21 days before symptom onset; MSM reported a median of three partners (IQR 1–8). Of 195 patients for whom data were available, 78 (40%) reported close contact with someone who had confirmed monkeypox. Overall, 30 (13%) of 226 patients were admitted to hospital; 16 (53%) of whom had severe illness, defined as hospital admission for clinical care rather than infection control. No deaths were reported. Compared with patients without HIV, patients with HIV were more likely to have diarrhoea (p=0·002), perianal rash or lesions (p=0·03), and a higher rash burden (median rash burden score 9 [IQR 6–21] for patients with HIV vs median rash burden score 6 [IQR 3–14] for patients without HIV; p<0·0001), but no differences were identified in the proportion of men who had severe illness by HIV status. Interpretation: Clinical manifestations of monkeypox infection differed by HIV status. Recommendations should be expanded to include pre-exposure monkeypox vaccination of groups at high risk of infection who plan to engage in sexual or close intimate contact. Funding: US Centers for Disease Control and Prevention, International Society of Travel Medicine.

Background: : Travelers' diarrhea causes significant morbidity including some sequelae, lost travel time and opportunity cost to both travelers and countries receiving travelers. Effective prevention and treatment are needed to reduce these negative impacts. Methods: : This critical appraisal of the literature and expert consensus guideline development effort asked several key questions related to antibiotic and non-antibiotic prophylaxis and treatment, utility of available diagnostics, impact of multi-drug resistant (MDR) colonization associated with travel and travelers' diarrhea, and how our understanding of the gastrointestinal microbiome should influence current practice and future research. Studies related to these key clinical areas were assessed for relevance and quality. Based on this critical appraisal, guidelines were developed and voted on using current standards for clinical guideline development methodology. Results: : New definitions for severity of travelers' diarrhea were developed. A total of 20 graded recommendations on the topics of prophylaxis, diagnosis, therapy and follow-up were developed. In addition, three non-graded consensus-based statements were adopted. Conclusions: : Prevention and treatment of travelers' diarrhea requires action at the provider, traveler and research community levels. Strong evidence supports the effectiveness of antimicrobial therapy in most cases of moderate to severe travelers' diarrhea, while either increasing intake of fluids only or loperamide or bismuth subsalicylate may suffice for most cases of mild diarrhea. Further studies are needed to address knowledge gaps regarding optimal therapies, the individual, community and global health risks of MDR acquisition, manipulation of the microbiome in prevention and treatment and the utility of laboratory testing in returning travelers with persistent diarrhea.