Evaluation of a Screening Method for the Detection of Colistin-Resistant Enterobacteriaceae in Stool.

Emergence of mobile colistin resistance (mcr)-containing Enterobacteriaceae is a public health threat, prompting enhanced surveillance through the Centers for Disease Control and Prevention. We evaluated a selective culture medium for the isolation of Enterobacteriaceae with non-wild-type colistin minimum inhibitory concentrations, including those with mcr-1 genes, in spiked stool samples.

Characteristics and preparation of the last-minute traveler: analysis of vaccine usage in the Global TravEpiNet Consortium.

BACKGROUND: Last-minute travellers (LMTs) present challenges for health care providers because they may have insufficient time for recommended vaccinations or pre-travel preparation. Our objective was to obtain a better understanding of LMTs in order to help travel medicine providers develop improved strategies to decrease the number of LMTs and potentially reduce travel-related morbidity. METHODS: We defined LMTs as travellers with a departure date of 7 days or fewer from the medical encounter. We analysed the characteristics and health preparation of 12 494 LMTs who presented to a network of US clinical practices for pre-travel health advice between January 2009 and December 2015. RESULTS: LMTs comprised 16% of all travellers. More LMTs than non-LMTs travelled for business or to visit friends and relatives (VFR) (26% vs 16% and 15% vs 8%, respectively; P < 0.0001). More LMTs also travelled for longer than 1 month (27% vs 21%; P < 0.0001) and visited only urban areas (40% vs 29%; P < 0.0001). At least one travel vaccine was deferred by 18% of LMTs because of insufficient time before departure. Vaccines that required multiple vaccinations, such as Japanese encephalitis and rabies, were the most likely to be deferred because of time constraints. CONCLUSION: Interventions to improve the timing of pre-travel health consultations should be developed, particularly for business and VFR travellers. Recently endorsed accelerated vaccine schedules for Japanese encephalitis and rabies may help some LMTs receive protection against these infections despite late presentation for pre-travel health care.

Water quality, availability, and acute gastroenteritis on the Navajo Nation - a pilot case-control study.

The Navajo Nation includes approximately 250,000 American Indians living in a remote high desert environment with limited access to public water systems. We conducted a pilot case-control study to assess associations between acute gastroenteritis (AGE) and water availability, use patterns, and quality. Case patients with AGE and non-AGE controls who presented for care to two Indian Health Service hospitals were recruited. Data on demographics and water use practices were collected using a standard questionnaire. Household drinking water was tested for presence of pathogens, coliforms, and residual chlorine. Sixty-one subjects (32 cases and 29 controls) participated in the study. Cases and controls were not significantly different with respect to water sources, quality, or patterns of use. Twenty-one percent (n = 12) of study participants resided in dwellings not connected to a community water system. Eleven percent (n = 7) of subjects reported drinking hauled water from unregulated sources. Coliform bacteria were present in 44% (n = 27) of household water samples, and 68% (n = 40) of samples contained residual chlorine concentrations of <0.2 mg/L. This study highlights issues with water availability, quality, and use patterns within the Navajo Nation, including sub-optimal access to community water systems, and use of water hauled from unregulated sources.

Potentially Serious Drug Interactions Resulting From the Pretravel Health Encounter.

Travelers seen for pretravel health encounters are frequently prescribed new travel-related medications, which may interact with their previously prescribed medications. In a cohort of 76 324 travelers seen at 23 US clinics, we found that 2650 (3.5%) travelers were prescribed travel-related medications with potential for serious drug interactions.

Infectious diseases acquired by international travellers visiting the USA.

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.

Leptospirosis among Returned Travelers: A GeoSentinel Site Survey and Multicenter Analysis-1997-2016.

Leptospirosis is a potentially fatal emerging zoonosis with worldwide distribution and a broad range of clinical presentations and exposure risks. It typically affects vulnerable populations in (sub)tropical countries but is increasingly reported in travelers as well. Diagnostic methods are cumbersome and require further improvement. Here, we describe leptospirosis among travelers presenting to the GeoSentinel Global Surveillance Network. We performed a descriptive analysis of leptospirosis cases reported in GeoSentinel from January 1997 through December 2016. We included 180 travelers with leptospirosis (mostly male; 74%; mostly tourists; 81%). The most frequent region of infection was Southeast Asia (52%); the most common source countries were Thailand (N = 52), Costa Rica (N = 13), Indonesia, and Laos (N = 11 each). Fifty-nine percent were hospitalized; one fatality was reported. We also distributed a supplemental survey to GeoSentinel sites to assess clinical and diagnostic practices. Of 56 GeoSentinel sites, three-quarters responded to the survey. Leptospirosis was reported to have been most frequently considered in febrile travelers with hepatic and renal abnormalities and a history of freshwater exposure. Serology was the most commonly used diagnostic method, although convalescent samples were reported to have been collected infrequently. Within GeoSentinel, leptospirosis was diagnosed mostly among international tourists and caused serious illness. Clinical suspicion and diagnostic workup among surveyed GeoSentinel clinicians were mainly triggered by a classical presentation and exposure history, possibly resulting in underdiagnosis. Suboptimal usage of available diagnostic methods may have resulted in additional missed, or misdiagnosed, cases.

Business travel-associated illness: a GeoSentinel analysis.

Background: Analysis of a large cohort of business travelers will help clinicians focus on frequent and serious illnesses. We aimed to describe travel-related health problems in business travelers. Methods: GeoSentinel Surveillance Network consists of 64 travel and tropical medicine clinics in 29 countries; descriptive analysis was performed on ill business travelers, defined as persons traveling for work, evaluated after international travel 1 January 1997 through 31 December 2014. Results: Among 12 203 business travelers seen 1997-2014 (14 045 eligible diagnoses), the majority (97%) were adults aged 20-64 years; most (74%) reported from Western Europe or North America; two-thirds were male. Most (86%) were outpatients. Fewer than half (45%) reported a pre-travel healthcare encounter. Frequent regions of exposure were sub-Saharan Africa (37%), Southeast Asia (15%) and South Central Asia (14%). The most frequent diagnoses were malaria (9%), acute unspecified diarrhea (8%), viral syndrome (6%), acute bacterial diarrhea (5%) and chronic diarrhea (4%). Species was reported for 973 (90%) of 1079 patients with malaria, predominantly Plasmodium falciparum acquired in sub-Saharan Africa. Of 584 (54%) with malaria chemoprophylaxis information, 92% took none or incomplete courses. Thirteen deaths were reported, over half of which were due to malaria; others succumbed to pneumonia, typhoid fever, rabies, melioidosis and pyogenic abscess. Conclusions: Diarrheal illness was a major cause of morbidity. Malaria contributed substantial morbidity and mortality, particularly among business travelers to sub-Saharan Africa. Underuse or non-use of chemoprophylaxis contributed to malaria cases. Deaths in business travelers could be reduced by improving adherence to malaria chemoprophylaxis and targeted vaccination for vaccine-preventable diseases. Pre-travel advice is indicated for business travelers and is currently under-utilized and needs improvement.

Malaria after international travel: a GeoSentinel analysis, 2003-2016.

BACKGROUND: More than 30,000 malaria cases are reported annually among international travellers. Despite improvements in malaria control, malaria continues to threaten travellers due to inaccurate perception of risk and sub-optimal pre-travel preparation. METHODS: Records with a confirmed malaria diagnosis after travel from January 2003 to July 2016 were obtained from GeoSentinel, a global surveillance network of travel and tropical medicine providers that monitors travel-related morbidity. Records were excluded if exposure country was missing or unascertainable or if there was a concomitant acute diagnosis unrelated to malaria. Records were analyzed to describe the demographic and clinical characteristics of international travellers with malaria. RESULTS: There were 5689 travellers included; 325 were children <18 years. More than half (53%) were visiting friends and relatives (VFRs). Most (83%) were exposed in sub-Saharan Africa. The median trip duration was 32 days (interquartile range 20-75); 53% did not have a pre-travel visit. More than half (62%) were hospitalized; children were hospitalized more frequently than adults (73 and 62%, respectively). Ninety-two per cent had a single Plasmodium species diagnosis, most frequently Plasmodium falciparum (4011; 76%). Travellers with P. falciparum were most frequently VFRs (60%). More than 40% of travellers with a trip duration ≤7 days had Plasmodium vivax. There were 444 (8%) travellers with severe malaria; 31 children had severe malaria. Twelve travellers died. CONCLUSION: Malaria remains a serious threat to international travellers. Efforts must focus on preventive strategies aimed on children and VFRs, and chemoprophylaxis access and preventive measure adherence should be emphasized.

Elevation as a proxy for mosquito-borne Zika virus transmission in the Americas.

INTRODUCTION: When Zika virus (ZIKV) first began its spread from Brazil to other parts of the Americas, national-level travel notices were issued, carrying with them significant economic consequences to affected countries. Although regions of some affected countries were likely unsuitable for mosquito-borne transmission of ZIKV, the absence of high quality, timely surveillance data made it difficult to confidently demarcate infection risk at a sub-national level. In the absence of reliable data on ZIKV activity, a pragmatic approach was needed to identify subnational geographic areas where the risk of ZIKV infection via mosquitoes was expected to be negligible. To address this urgent need, we evaluated elevation as a proxy for mosquito-borne ZIKV transmission. METHODS: For sixteen countries with local ZIKV transmission in the Americas, we analyzed (i) modelled occurrence of the primary vector for ZIKV, Aedes aegypti, (ii) human population counts, and (iii) reported historical dengue cases, specifically across 100-meter elevation levels between 1,500m and 2,500m. Specifically, we quantified land area, population size, and the number of observed dengue cases above each elevation level to identify a threshold where the predicted risks of encountering Ae. aegypti become negligible. RESULTS: Above 1,600m, less than 1% of each country's total land area was predicted to have Ae. aegypti occurrence. Above 1,900m, less than 1% of each country's resident population lived in areas where Ae. aegypti was predicted to occur. Across all 16 countries, 1.1% of historical dengue cases were reported above 2,000m. DISCUSSION: These results suggest low potential for mosquito-borne ZIKV transmission above 2,000m in the Americas. Although elevation is a crude predictor of environmental suitability for ZIKV transmission, its constancy made it a pragmatic input for policy decision-making during this public health emergency.

Clostridium difficile infection in returning travellers.

Background: There is increasing recognition of the contribution of community-acquired cases to the global burden of Clostridium difficile infection (CDI). The epidemiology of CDI among international travellers is poorly understood, and factors associated with international travel, such as antibiotic use and changes in gut microbiota, could potentially put travellers at higher risk. Methods: We summarized demographic, travel-associated and geographic characteristics of travellers with CDI in the GeoSentinel database from 1997 to 2015. We also surveyed GeoSentinel sites to compare various testing indications, approaches, and diagnostic modalities. Results: We identified 260 GeoSentinel records, including 187 that satisfied criteria for analysis (confirmed cases in non-immigrant travellers aged >2 years, seen <12 weeks post-travel). CDI was reported in all age groups and in travellers to all world regions; the largest proportions of cases having destinations in Asia (31%), Central/South America or the Caribbean (30%) and Africa (24%). Our site survey revealed substantial heterogeneity of testing approaches between sites; the most commonly used test was the C. difficile toxin gene PCR. Conclusions: CDI is encountered in returning international travellers, although there is considerable variability in testing practices. These data underscore the importance of awareness of C. difficile as a potential cause of travel-associated diarrhoea.

Travel-Associated Zika Virus Disease Acquired in the Americas Through February 2016: A GeoSentinel Analysis.

Background: Zika virus has spread rapidly in the Americas and has been imported into many nonendemic countries by travelers. Objective: To describe clinical manifestations and epidemiology of Zika virus disease in travelers exposed in the Americas. Design: Descriptive, using GeoSentinel records. Setting: 63 travel and tropical medicine clinics in 30 countries. Patients: Ill returned travelers with a confirmed, probable, or clinically suspected diagnosis of Zika virus disease seen between January 2013 and 29 February 2016. Measurements: Frequencies of demographic, trip, and clinical characteristics and complications. Results: Starting in May 2015, 93 cases of Zika virus disease were reported. Common symptoms included exanthema (88%), fever (76%), and arthralgia (72%). Fifty-nine percent of patients were exposed in South America; 71% were diagnosed in Europe. Case status was established most commonly by polymerase chain reaction (PCR) testing of blood and less often by PCR testing of other body fluids or serology and plaque-reduction neutralization testing. Two patients developed Guillain-Barré syndrome, and 3 of 4 pregnancies had adverse outcomes (microcephaly, major fetal neurologic abnormalities, and intrauterine fetal death). Limitation: Surveillance data collected by specialized clinics may not be representative of all ill returned travelers, and denominator data are unavailable. Conclusion: These surveillance data help characterize the clinical manifestations and adverse outcomes of Zika virus disease among travelers infected in the Americas and show a need for global standardization of diagnostic testing. The serious fetal complications observed in this study highlight the importance of travel advisories and prevention measures for pregnant women and their partners. Travelers are sentinels for global Zika virus circulation and may facilitate further transmission. Primary Funding Source: Centers for Disease Control and Prevention, International Society of Travel Medicine, and Public Health Agency of Canada.

Characteristics of US Travelers to Zika Virus-Affected Countries in the Americas, March 2015-October 2016.

Zika virus has recently been introduced to the Americas and is spreading rapidly. We evaluated the characteristics of US travelers to Zika virus-affected countries who were seen at Global TravEpiNet sites during March 2015-October 2016. Nearly three quarters of travelers were men or women of reproductive age.

Interagency and Commercial Collaboration During an Investigation of Chikungunya and Dengue Among Returning Travelers to the United States.

Public health investigations can require intensive collaboration between numerous governmental and nongovernmental organizations. We describe an investigation involving several governmental and nongovernmental partners that was successfully planned and performed in an organized, comprehensive, and timely manner with several governmental and nongovernmental partners.

Multistate US Outbreak of Rapidly Growing Mycobacterial Infections Associated with Medical Tourism to the Dominican Republic, 2013-2014(1).

During 2013, the Maryland Department of Health and Mental Hygiene in Baltimore, MD, USA, received report of 2 Maryland residents whose surgical sites were infected with rapidly growing mycobacteria after cosmetic procedures at a clinic (clinic A) in the Dominican Republic. A multistate investigation was initiated; a probable case was defined as a surgical site infection unresponsive to therapy in a patient who had undergone cosmetic surgery in the Dominican Republic. We identified 21 case-patients in 6 states who had surgery in 1 of 5 Dominican Republic clinics; 13 (62%) had surgery at clinic A. Isolates from 12 (92%) of those patients were culture-positive for Mycobacterium abscessus complex. Of 9 clinic A case-patients with available data, all required therapeutic surgical intervention, 8 (92%) were hospitalized, and 7 (78%) required ≥3 months of antibacterial drug therapy. Healthcare providers should consider infection with rapidly growing mycobacteria in patients who have surgical site infections unresponsive to standard treatment.

Profile of illness in Syrian refugees: A GeoSentinel analysis, 2013 to 2015.

Screening of 488 Syrian unaccompanied minor refugees (< 18 years-old) in Berlin showed low prevalence of intestinal parasites (Giardia, 7%), positive schistosomiasis serology (1.4%) and absence of hepatitis B. Among 44 ill adult Syrian refugees examined at GeoSentinel clinics worldwide, cutaneous leishmaniasis affected one in three patients; other noteworthy infections were active tuberculosis (11%) and chronic hepatitis B or C (9%). These data can contribute to evidence-based guidelines for infectious disease screening of Syrian refugees.

Chikungunya and Dengue Virus Infections Among United States Community Service Volunteers Returning from the Dominican Republic, 2014.

Chikungunya spread throughout the Dominican Republic (DR) after the first identified laboratory-confirmed cases were reported in April 2014. In June 2014, a U.S.-based service organization operating in the DR reported chikungunya-like illnesses among several staff. We assessed the incidence of chikungunya virus (CHIKV) and dengue virus (DENV) infection and illnesses and evaluated adherence to mosquito avoidance measures among volunteers/staff deployed in the DR who returned to the United States during July-August 2014. Investigation participants completed a questionnaire that collected information on demographics, medical history, self-reported illnesses, and mosquito exposures and avoidance behaviors and provided serum for CHIKV and DENV diagnostic testing by reverse transcription polymerase chain reaction and IgM enzyme-linked immunosorbent assay. Of 102 participants, 42 (41%) had evidence of recent CHIKV infection and two (2%) had evidence of recent DENV infection. Of the 41 participants with evidence of recent CHIKV infection only, 39 (95%) reported fever, 37 (90%) reported rash, and 37 (90%) reported joint pain during their assignment. All attended the organization's health trainings, and 89 (87%) sought a pretravel health consultation. Most (∼95%) used insect repellent; however, only 30% applied it multiple times daily and < 5% stayed in housing with window/door screens. In sum, CHIKV infections were common among these volunteers during the 2014 chikungunya epidemic in the DR. Despite high levels of preparation, reported adherence to mosquito avoidance measures were inconsistent. Clinicians should discuss chikungunya with travelers visiting areas with ongoing CHIKV outbreaks and should consider chikungunya when diagnosing febrile illnesses in travelers returning from affected areas.

Measles in the 21st Century, a Continuing Preventable Risk to Travelers: Data From the GeoSentinel Global Network.

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.