Addressing a Yellow Fever Vaccine Shortage - United States, 2016-2017.

Recent manufacturing problems resulted in a shortage of the only U.S.-licensed yellow fever vaccine. This shortage is expected to lead to a complete depletion of yellow fever vaccine available for the immunization of U.S. travelers by mid-2017. CDC, the Food and Drug Administration (FDA), and Sanofi Pasteur are collaborating to ensure a continuous yellow fever vaccine supply in the United States. As part of this collaboration, Sanofi Pasteur submitted an expanded access investigational new drug (eIND) application to FDA in September 2016 to allow for the importation and use of an alternative yellow fever vaccine manufactured by Sanofi Pasteur France, with safety and efficacy comparable to the U.S.-licensed vaccine; the eIND was accepted by FDA in October 2016. The implementation of this eIND protocol included developing a systematic process for selecting a limited number of clinic sites to provide the vaccine. CDC and Sanofi Pasteur will continue to communicate with the public and other stakeholders, and CDC will provide a list of locations that will be administering the replacement vaccine at a later date.

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.

Economics of malaria prevention in US travelers to West Africa.

BACKGROUND: Pretravel health consultations help international travelers manage travel-related illness risks through education, vaccination, and medication. This study evaluated costs and benefits of that portion of the health consultation associated with malaria prevention provided to US travelers bound for West Africa. METHODS: The estimated change in disease risk and associated costs and benefits resulting from traveler adherence to malaria chemoprophylaxis were calculated from 2 perspectives: the healthcare payer's and the traveler's. We used data from the Global TravEpiNet network of US travel clinics that collect de-identified pretravel data for international travelers. Disease risk and chemoprophylaxis effectiveness were estimated from published medical reports. Direct medical costs were obtained from the Nationwide Inpatient Sample and published literature. RESULTS: We analyzed 1029 records from January 2009 to January 2011. Assuming full adherence to chemoprophylaxis regimens, consultations saved healthcare payers a per-traveler average of $14 (9-day trip) to $372 (30-day trip). For travelers, consultations resulted in a range of net cost of $20 (9-day trip) to a net savings of $32 (30-day trip). Differences were mostly driven by risk of malaria in the destination country. CONCLUSIONS: Our model suggests that healthcare payers save money for short- and longer-term trips, and that travelers save money for longer trips when travelers adhere to malaria recommendations and prophylactic regimens in West Africa. This is a potential incentive to healthcare payers to offer consistent pretravel preventive care to travelers. This financial benefit complements the medical benefit of reducing the risk of malaria.

Acute muscular sarcocystosis: an international investigation among ill travelers returning from Tioman Island, Malaysia, 2011-2012.

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.

Airport exit and entry screening for Ebola--August-November 10, 2014.

In response to the largest recognized Ebola virus disease epidemic now occurring in West Africa, the governments of affected countries, CDC, the World Health Organization (WHO), and other international organizations have collaborated to implement strategies to control spread of the virus. One strategy recommended by WHO calls for countries with Ebola transmission to screen all persons exiting the country for "unexplained febrile illness consistent with potential Ebola infection." Exit screening at points of departure is intended to reduce the likelihood of international spread of the virus. To initiate this strategy, CDC, WHO, and other global partners were invited by the ministries of health of Guinea, Liberia, and Sierra Leone to assist them in developing and implementing exit screening procedures. Since the program began in August 2014, an estimated 80,000 travelers, of whom approximately 12,000 were en route to the United States, have departed by air from the three countries with Ebola transmission. Procedures were implemented to deny boarding to ill travelers and persons who reported a high risk for exposure to Ebola; no international air traveler from these countries has been reported as symptomatic with Ebola during travel since these procedures were implemented.

Notes from the field: rapidly growing nontuberculous Mycobacterium wound infections among medical tourists undergoing cosmetic surgeries in the Dominican Republic--multiple states, March 2013-February 2014.

In August 2013, the Maryland Department of Health and Mental Hygiene (MDHMH) was notified of two persons with rapidly growing nontuberculous mycobacterial (RG-NTM) surgical-site infections. Both patients had undergone surgical procedures as medical tourists at the same private surgical clinic (clinic A) in the Dominican Republic the previous month. Within 7 days of returning to the United States, both sought care for symptoms that included surgical wound abscesses, clear fluid drainage, pain, and fever. Initial antibiotic therapy was ineffective. Material collected from both patients' wounds grew Mycobacterium abscessus exhibiting a high degree of antibiotic resistance characteristic of this organism.

Travel Health-Related Preparation Practices of Institutions of Higher Education and Occurrence of Health-Related Events among Undergraduate Students Studying Abroad, 2018-2021.

Background: Knowledge of specific health-related events encountered by students studying abroad and the availability and use of pre-travel healthcare for these students is lacking. Methods: Anonymous web-based questionnaires were sent to study abroad offices, student health centers, and undergraduate students after studying abroad at eight institutions of higher education in the United States and Ireland from 2018-2021. Analyses were descriptive; relative risks and 95% confidence intervals were calculated for health-related events. Results: One study abroad office required a pre-travel consultation. All student health centers had pre-travel counseling available. Among 686 students, there were 307 infectious and 1,588 non-infectious health-related issues; 12 students (2%) were hospitalized. Duration of travel and timing of a pre-travel consultation impacted the risk of health-related events. Certain mental health conditions were associated with increased risk of alcohol and drug use. Conclusion: Future studies should address the optimal timing and best practices to optimize health for students studying abroad.

Global TravEpiNet: a national consortium of clinics providing care to international travelers--analysis of demographic characteristics, travel destinations, and pretravel healthcare of high-risk US international travelers, 2009-2011.

BACKGROUND: International travel poses a risk of destination-specific illness and may contribute to the global spread of infectious diseases. Despite this, little is known about the health characteristics and pretravel healthcare of US international travelers, particularly those at higher risk of travel-associated illness. METHODS: We formed a national consortium (Global TravEpiNet) of 18 US clinics registered to administer yellow fever vaccination. We collected data regarding demographic and health characteristics, destinations, purpose of travel, and pretravel healthcare from 13235 international travelers who sought pretravel consultation at these sites from January 2009 through January 2011. RESULTS: The destinations and itineraries of Global TravEpiNet travelers differed from those of the overall population of US international travelers. The majority of Global TravEpiNet travelers were visiting low- or lower-middle-income countries, and Africa was the most frequently visited region. Seventy-five percent of travelers were visiting malaria-endemic countries, and 38% were visiting countries endemic for yellow fever. Fifty-nine percent of travelers reported ≥1 medical condition. Atovaquone/proguanil was the most commonly prescribed antimalarial drug, and most travelers received an antibiotic for self-treatment of travelers' diarrhea. Hepatitis A and typhoid were the most frequently administered vaccines. CONCLUSIONS: Data from Global TravEpiNet provide insight into the characteristics and pretravel healthcare of US international travelers who are at increased risk of travel-associated illness due to itinerary, purpose of travel, or existing medical conditions. Improved understanding of this epidemiologically significant population may help target risk-reduction strategies and interventions to limit the spread of infections related to global travel.

Schistosomiasis among recreational users of Upper Nile River, Uganda, 2007.

After recreational exposure to river water in Uganda, 12 (17%) of 69 persons had evidence of schistosome infection. Eighteen percent self-medicated with praziquantel prophylaxis immediately after exposure, which was not appropriate. Travelers to schistosomiasis-endemic areas should consult a travel medicine physician.

Enabling clinicians to easily find location-based travel health recommendations-is innovation needed?

Background: The types of place names and the level of geographic detail that patients report to clinicians regarding their intended travel itineraries vary. The reported place names may not match those in published travel health recommendations, making traveler-specific recommendations potentially difficult and time-consuming to identify. Most published recommendations are at the country level; however, subnational recommendations exist when documented disease risk varies within a country, as for malaria and yellow fever. Knowing the types of place names reported during consultations would be valuable for developing more efficient ways of searching and identifying recommendations, hence we inventoried these descriptors and identified patterns in their usage. Methods: The data analyzed were previously collected individual travel itineraries from pretravel consultations performed at Global TravEpiNet (GTEN) travel clinic sites. We selected a clinic-stratified random sample of records from 18 GTEN clinics that contained responses to an open-ended question describing itineraries. We extracted and classified place names into nine types and analyzed patterns relative to common travel-related demographic variables. Results: From the 1756 itineraries sampled, 1570 (89%) included one or more place names, totaling 3366 place names. The frequency of different types of place names varied considerably: 2119 (63%) populated place, 336 (10%) tourist destination, 283 (8%) physical geographic area, 206 (6%) vague subnational area, 163 (5%) state, 153 (5%) country, 48 (1%) county, 12 (1%) undefined. Conclusions: The types of place names used by travelers to describe travel itineraries during pretravel consultations were often different from the ones referenced in travel health recommendations. This discrepancy means that clinicians must use additional maps, atlases or online search tools to cross-reference the place names given to the available recommendations. Developing new clinical tools that use geographic information systems technology would make it easier and faster for clinicians to find applicable recommendations for travelers.

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.

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.

Evidence-based risk assessment and communication: a new global dengue-risk map for travellers and clinicians.

BACKGROUND: International travel can expose travellers to pathogens not commonly found in their countries of residence, like dengue virus. Travellers and the clinicians who advise and treat them have unique needs for understanding the geographic extent of risk for dengue. Specifically, they should assess the need for prevention measures before travel and ensure appropriate treatment of illness post-travel. Previous dengue-risk maps published in the Centers for Disease Control and Prevention's Yellow Book lacked specificity, as there was a binary (risk, no risk) classification. We developed a process to compile evidence, evaluate it and apply more informative risk classifications. METHODS: We collected more than 839 observations from official reports, ProMED reports and published scientific research for the period 2005-2014. We classified each location as frequent/continuous risk if there was evidence of more than 10 dengue cases in at least three of the previous 10 years. For locations that did not fit this criterion, we classified locations as sporadic/uncertain risk if the location had evidence of at least one locally acquired dengue case during the last 10 years. We used expert opinion in limited instances to augment available data in areas where data were sparse. RESULTS: Initial categorizations classified 134 areas as frequent/continuous and 140 areas as sporadic/uncertain. CDC subject matter experts reviewed all initial frequent/continuous and sporadic/uncertain categorizations and the previously uncategorized areas. From this review, most categorizations stayed the same; however, 11 categorizations changed from the initial determinations. CONCLUSIONS: These new risk classifications enable detailed consideration of dengue risk, with clearer meaning and a direct link to the evidence that supports the specific classification. Since many infectious diseases have dynamic risk, strong geographical heterogeneities and varying data quality and availability, using this approach for other diseases can improve the accuracy, clarity and transparency of risk communication.

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.

Possible rabies exposures in Peace Corps volunteers, 2011.

We surveyed Peace Corps Medical Officers (PCMOs) to determine the frequency of and responses to possible rabies exposures of U.S. Peace Corps volunteers (PCVs). Surveys were sent to 56 PCMOs serving in countries with moderate or high rabies vaccine recommendations from the U.S. Centers for Disease Control and Prevention (CDC), of which 38 (68%) responded. Thirty-seven PCMOs reported that, of 4,982 PCVs, 140 (3%) experienced possible rabies exposures. Of these, 125 (89%) had previously received rabies vaccination, 129 (92%) presented with adequately cleansed wounds, and 106 (76%) were deemed to require and were given post-exposure prophylaxis (PEP). Of 35 respondents, 30 (86%) reported that rabies vaccine was always accessible to PCVs in their country within 24 hours. Overall, the Peace Corps is successful at preventing and treating possible rabies exposures. However, this study identified a few gaps in policy implementation. The Peace Corps should continue and strengthen efforts to provide education, preexposure vaccination, and PEP to PCVs.

The global availability of rabies immune globulin and rabies vaccine in clinics providing indirect care to travelers.

We assessed rabies vaccine (RV) and immune globulin (RIG) availability on the local market by querying US Embassy medical staff worldwide. Of 112 responses, 23% were from West, Central, and East Africa. RV and RIG availability varied by region. Possible rabies exposures accounted for 2% of all travelers' health inquiries.

Health and safety issues for travelers attending the World Cup and Summer Olympic and Paralympic Games in Brazil, 2014 to 2016.

IMPORTANCE: Travelers from around the globe will attend the 2014 Fédération Internationale de Football Association (FIFA) World Cup and the 2016 Olympic and Paralympic Games in Brazil. Travelers to these mass gathering events may be exposed to a range of health risks, including a variety of infectious diseases. Most travelers who become ill will present to their primary care physicians, and thus it is important that clinicians are aware of the risks their patients encountered. OBJECTIVE: To highlight health and safety concerns for people traveling to these events in Brazil so that health care practitioners can better prepare travelers before they travel and more effectively diagnose and treat travelers after they return. EVIDENCE REVIEW: We reviewed both peer-reviewed and gray literature to identify health outcomes associated with travel to Brazil and mass gatherings. Thirteen specific infectious diseases are described in terms of signs, symptoms, and treatment. Relevant safety and security concerns are also discussed. FINDINGS: Travelers to Brazil for mass gathering events face unique health risks associated with their travel. CONCLUSIONS AND RELEVANCE: Travelers should consult a health care practitioner 4 to 6 weeks before travel to Brazil and seek up-to-date information regarding their specific itineraries. For the most up-to-date information, health care practitioners can visit the Centers for Disease Control and Prevention (CDC) Travelers' Health website (http://wwwnc.cdc.gov/travel) or review CDC's Yellow Book online (http://wwwnc.cdc.gov/travel/page/yellowbook-home-2014).

Use of Japanese encephalitis vaccine in US travel medicine practices in Global TravEpiNet.

Few data regarding the use of Japanese encephalitis (JE) vaccine in clinical practice are available. We identified 711 travelers at higher risk and 7,578 travelers at lower risk for JE who were seen at US Global TravEpiNet sites from September of 2009 to August of 2012. Higher-risk travelers were younger than lower-risk travelers (median age = 29 years versus 40 years, P < 0.001). Over 70% of higher-risk travelers neither received JE vaccine during the clinic visit nor had been previously vaccinated. In the majority of these instances, clinicians determined that the JE vaccine was not indicated for the higher-risk traveler, which contradicts current recommendations of the Advisory Committee on Immunization Practices. Better understanding is needed of the clinical decision-making regarding JE vaccine in US travel medicine practices.