Search

We enrolled arriving international air travelers in a severe acute respiratory syndrome coronavirus 2 genomic surveillance program. We used molecular testing of pooled nasal swabs and sequenced positive samples for sublineage. Traveler-based surveillance provided early-warning variant detection, reporting the first US Omicron BA.2 and BA.3 in North America.

On August 29, 2021, the United States government oversaw the emergent establishment of Operation Allies Welcome (OAW), led by the U.S. Department of Homeland Security (DHS) and implemented by the U.S. Department of Defense (DoD) and U.S. Department of State (DoS), to safely resettle U.S. citizens and Afghan nationals from Afghanistan to the United States. Evacuees were temporarily housed at several overseas locations in Europe and Asia* before being transported via military and charter flights through two U.S. international airports, and onward to eight U.S. military bases

Background International travel facilitates SARS-CoV-2 spread globally. Early detection of variants among arriving international travelers could provide viral information about introduction of variants with differing infectivity, virulence, and vaccine effectiveness, enabling adjustments to treatment and prevention strategies. We initiated a genomic surveillance program at 4 US airports to detect SARS-CoV-2 variants among arriving international travelers. Methods Between November 29, 2021-April 24, 2022, we enrolled arriving air travelers (≥18 years) from flights originating in 16 countries on 5 continents. At four airports, participants self-collected nasal swab samples that were pooled with 5–25 other samples by country of flight. Participants were also given a take-home saliva collection kit; saliva was collected 3-5 days after arrival and mailed back to the laboratory. SARS-CoV-2 reverse transcription–polymerase chain reaction (RT-PCR) was performed on all samples at the laboratory. Positives underwent whole genome sequencing. Demographic, clinical, and travel information was collected. Results We enrolled 28,656 travelers; median age was 42 years (interquartile range 31-55), 48% were female, and 99.4% self-reported COVID-19 vaccination. Overall, 19% (504/2,666) of pooled and 7.5% (285/3804) of individual samples were positive for SARS-CoV-2. Highest pool positivity of 46% occurred during January 3–10, 2022 (Figure 1). Omicron variant accounted for 97% of sequences (Figure 2). We detected the earliest reporting of Omicron sub-lineages BA.2 and BA.3 (7 and 43 days earlier than reported elsewhere) in the United States and North America, respectively. During April 4–18, we detected an increasing trend of pool positivity among travelers on South African flights, detecting one of the first US-reported BA.4 sub-lineages consistent with early surge of cases in South Africa. Weekly pooled positivity for travelers on South African flights aligned with World Health Organization (WHO)-reported 7-day COVID-19 incidence rates over the same period (Figure 3). Conclusion This genomic sequencing surveillance platform is a model for traveler-based SARS-CoV-2 genomic surveillance that can be used as an early warning system to detect future outbreaks and pandemics. Disclosures Renee Wegrzyn, PhD, Ginkgo Bioworks: Stocks/Bonds Robert C. Morfino, MBA, Ginkgo Bioworks Inc: Employee|Ginkgo Bioworks Inc: Stocks/Bonds Scott Milford, n/a, XpresSpa Group, Inc: Stocks/Bonds Scott Milford, n/a, XpresSpa Group, Inc: Stocks/Bonds Ezra T. Ernst, n/a, XpresSpa Group, Inc: Ownership Interest|XpresSpa Group, Inc: Stocks/Bonds William W. Darrow, n/a, XpresSpa Group, Inc: Stocks/Bonds Siyao Lisa Li, n/a, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Thomas Aichele, n/a, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Andrew Rothstein, n/a, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Benjamin Rome, MBA, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Gabrielle Woronoff, PhD, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Keith Robison, PhD, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Dongjuan Dai, PhD, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Allison Hicks, PhD, Ginkgo Bioworks: I am a current employee|Ginkgo Bioworks: Stocks/Bonds Bryan Cosca, n/a, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Alex Plocik, PhD, Ginkgo Bioworks, Inc: Grant/Research Support|Ginkgo Bioworks, Inc: Stocks/Bonds Birgitte Simen, PhD, Ginkgo Bioworks: I am a current employee|Ginkgo Bioworks: Stocks/Bonds.

Background Cruise travel contributed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission when there were relatively few cases in the United States. By 14 March 2020, the Centers for Disease Control and Prevention (CDC) issued a No Sail Order suspending US cruise operations; the last US passenger ship docked on 16 April. Methods We analyzed SARS-CoV-2 outbreaks on cruises in US waters or carrying US citizens and used regression models to compare voyage characteristics. We used compartmental models to simulate the potential impact of 4 interventions (screening for coronavirus disease 2019 (COVID-19) symptoms; viral testing on 2 days and isolation of positive persons; reduction of passengers by 40%, crew by 20%, and reducing port visits to 1) for 7-day and 14-day voyages. Results During 19 January to 16 April 2020, 89 voyages on 70 ships had known SARS-CoV-2 outbreaks; 16 ships had recurrent outbreaks. There were 1669 reverse transcription polymerase chain reaction (RT-PCR)-confirmed SARS-CoV-2 infections and 29 confirmed deaths. Longer voyages were associated with more cases (adjusted incidence rate ratio, 1.10, 95% confidence interval [CI]: 1.03–1.17, P Conclusions SARS-CoV-2 outbreaks on cruises were common during January–April 2020. Despite all interventions modeled, cruise travel still poses a significant SARS-CoV-2 transmission risk.

Background Balancing the control of SARS-CoV-2 transmission with the resumption of travel is a global priority. Current recommendations include mitigation measures before, during, and after travel. Pre- and post-travel strategies including symptom monitoring, antigen or nucleic acid amplification testing, and quarantine can be combined in multiple ways considering different trade-offs in feasibility, adherence, effectiveness, cost, and adverse consequences. Methods We used a mathematical model to analyze the expected effectiveness of symptom monitoring, testing, and quarantine under different estimates of the infectious period, test-positivity relative to time of infection, and test sensitivity to reduce the risk of transmission from infected travelers during and after travel. Results If infection occurs 0–7 days prior to travel, immediate isolation following symptom onset prior to or during travel reduces risk of transmission while traveling by 30–35%. Pre-departure testing can further reduce risk, with testing closer to the time of travel being optimal even if test sensitivity is lower than an earlier test. For example, testing on the day of departure can reduce risk while traveling by 44–72%. For transmission risk after travel with infection time up to 7 days prior to arrival at the destination, isolation based on symptom monitoring reduced introduction risk at the destination by 42–56%. A 14-day quarantine after arrival, without symptom monitoring or testing, can reduce post-travel risk by 96–100% on its own. However, a shorter quarantine of 7 days combined with symptom monitoring and a test on day 5–6 after arrival is also effective (97--100%) at reducing introduction risk and is less burdensome, which may improve adherence. Conclusions Quarantine is an effective measure to reduce SARS-CoV-2 transmission risk from travelers and can be enhanced by the addition of symptom monitoring and testing. Optimal test timing depends on the effectiveness of quarantine: with low adherence or no quarantine, optimal test timing is close to the time of arrival; with effective quarantine, testing a few days later optimizes sensitivity to detect those infected immediately before or while traveling. These measures can complement recommendations such as social distancing, using masks, and hand hygiene, to further reduce risk during and after travel.

In January 2020, with support from the U.S. Department of Homeland Security (DHS), CDC instituted an enhanced entry risk assessment and management (screening) program for air passengers arriving from certain countries with widespread, sustained transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). The objectives of the screening program were to reduce the importation of COVID-19 cases into the United States and slow subsequent spread within states. Screening aimed to identify travelers with COVID-19-like illness or who had a known exposure to a person with COVID-19 and separate them from others. Screening also aimed to inform all screened travelers about self-monitoring and other recommendations to prevent disease spread and obtain their contact information to share with public health authorities in destination states. CDC delegated postarrival management of crew members to airline occupational health programs by issuing joint guidance with the Federal Aviation Administration.* During January 17-September 13, 2020, a total of 766,044 travelers were screened, 298 (0.04%) of whom met criteria for public health assessment; 35 (0.005%) were tested for SARS-CoV-2, and nine (0.001%) had a positive test result. CDC shared contact information with states for approximately 68% of screened travelers because of data collection challenges and some states' opting out of receiving data. The low case detection rate of this resource-intensive program highlighted the need for fundamental change in the U.S. border health strategy. Because SARS-CoV-2 infection and transmission can occur in the absence of symptoms and because the symptoms of COVID-19 are nonspecific, symptom-based screening programs are ineffective for case detection. Since the screening program ended on September 14, 2020, efforts to reduce COVID-19 importation have focused on enhancing communications with travelers to promote recommended preventive measures, reinforcing mechanisms to refer overtly ill travelers to CDC, and enhancing public health response capacity at ports of entry. More efficient collection of contact information for international air passengers before arrival and real-time transfer of data to U.S. health departments would facilitate timely postarrival public health management, including contact tracing, when indicated. Incorporating health attestations, predeparture and postarrival testing, and a period of limited movement after higher-risk travel, might reduce risk for transmission during travel and translocation of SARS-CoV-2 between geographic areas and help guide more individualized postarrival recommendations.

To determine prevalence of, seroprevalence of, and potential exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a cohort of evacuees returning to the United States from Wuhan, China, in January 2020, we conducted a cross-sectional study of quarantined evacuees from 1 repatriation flight. Overall, 193 of 195 evacuees completed exposure surveys and submitted upper respiratory or serum specimens or both at arrival in the United States. Nearly all evacuees had taken preventive measures to limit potential exposure while in Wuhan, and none had detectable SARS-CoV-2 in upper respiratory tract specimens, suggesting the absence of asymptomatic respiratory shedding among this group at the time of testing. Evidence of antibodies to SARS-CoV-2 was detected in 1 evacuee, who reported experiencing no symptoms or high-risk exposures in the previous 2 months. These findings demonstrated that this group of evacuees posed a low risk of introducing SARS-CoV-2 to the United States.

We enrolled arriving international air travelers in SARS-CoV-2 genomic surveillance, using molecular testing of pooled nasal swabs, and sequencing positive samples for viral lineage. Traveler-based genomic surveillance provided early warning variant detection; we reported the first U.S. Omicron BA.2 and first BA.3 in North America, weeks before next reported detection.

We enrolled arriving international air travelers in SARS-CoV-2 genomic surveillance, using molecular testing of pooled nasal swabs, and sequencing positive samples for viral sublineage. Traveler-based genomic surveillance provided early warning variant detection; we reported the first U.S. Omicron BA.2 and first BA.3 in North America, weeks before next reported detection.

Background While persons who receive immigrant and refugee visas are screened for active tuberculosis before admission into the United States, nonimmigrant visa applicants (NIVs) are not routinely screened and may enter the United States with infectious tuberculosis. Objectives We evaluated the costs and benefits of expanding pre-departure tuberculosis screening requirements to a subset of NIVs who arrive from a moderate (Mexico) or high (India) incidence tuberculosis country with temporary work visas. Methods We developed a decision tree model to evaluate the program costs and estimate the numbers of active tuberculosis cases that may be diagnosed in the United States in two scenarios: 1) “Screening”: screening and treatment for tuberculosis among NIVs in their home country with recommended U.S. follow-up for NIVs at elevated risk of active tuberculosis; and, 2) “No Screening” in their home country so that cases would be diagnosed passively and treatment occurs after entry into the United States. Costs were assessed from multiple perspectives, including multinational and U.S.-only perspectives. Results Under “Screening” versus “No Screening”, an estimated 179 active tuberculosis cases and 119 hospitalizations would be averted in the United States annually via predeparture treatment. From the U.S.-only perspective, this program would result in annual net cost savings of about $3.75 million. However, rom the multinational perspective, the screening program would cost $151,388 per U.S. case averted for Indian NIVs and $221,088 per U.S. case averted for Mexican NIVs. Conclusion From the U.S.-only perspective, the screening program would result in substantial cost savings in the form of reduced treatment and hospitalization costs. NIVs would incur increased pre-departure screening and treatment costs.

BackgroundThe Diamond Princess cruise ship was the site of a large outbreak of coronavirus disease 2019 (COVID-19). Of 437 Americans and their travel companions on the ship, 114 (26%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).MethodsWe interviewed 229 American passengers and crew after disembarkation following a ship-based quarantine to identify risk factors for infection and characterize transmission onboard the ship.ResultsThe attack rate for passengers in single-person cabins or without infected cabinmates was 18% (58/329), compared with 63% (27/43) for those sharing a cabin with an asymptomatic infected cabinmate, and 81% (25/31) for those with a symptomatic infected cabinmate. Whole genome sequences from specimens from passengers who shared cabins clustered together. Of 66 SARS-CoV-2-positive American travelers with complete symptom information, 14 (21%) were asymptomatic while on the ship. Among SARS-CoV-2-positive Americans, 10 (9%) required intensive care, of whom 7 were ≥70 years.ConclusionsOur findings highlight the high risk of SARS-CoV-2 transmission on cruise ships. High rates of SARS-CoV-2 positivity in cabinmates of individuals with asymptomatic infections suggest that triage by symptom status in shared quarters is insufficient to halt transmission. A high rate of intensive care unit admission among older individuals complicates the prospect of future cruise travel during the pandemic, given typical cruise passenger demographics. The magnitude and severe outcomes of this outbreak were major factors contributing to the Centers for Disease Control and Prevention’s decision to halt cruise ship travel in US waters in March 2020.

Background US-bound refugees undergo required health assessments overseas to identify and treat communicable diseases of public health significance—such as pulmonary tuberculosis—before migration. Immunizations are not required, leaving refugees at risk for vaccine-preventable diseases. In response, the US Centers for Disease Control and Prevention and the US Department of State developed and co-funded a global immunization program for US-bound refugees, implemented in 2012 in collaboration with the International Organization for Migration. Methods We describe the Vaccination Program for US-bound Refugees, including vaccination schedule development, program implementation and procedures, and responses to challenges. We estimate 2019 immunization coverage rates using the number of age-eligible refugees who received ≥1 dose of measles-containing vaccine during overseas health assessment, and calculated hepatitis B infection prevalence using hepatitis B surface antigen testing results. We report descriptive data on adverse events following immunization. Results By September 2019, the program was active in >80 countries on five continents. Nearly 320,000 examined refugees had ≥1 documented vaccine doses since program inception. During federal fiscal year 2019, 95% of arriving refugees had ≥1 documented measles-containing vaccine. The program’s immunization schedule included eleven vaccines preventing fourteen diseases. In 2015–2019, only two vaccine preventable disease-associated refugee group travel cancellations occurred, compared to 2–8 cancellations annually prior to program initiation. To maintain uniform standards, dedicated staff and program-specific protocols for vaccination and monitoring were introduced. Conclusions An overseas immunization program was successfully implemented for US-bound refugees. Due to reductions in refugee movement cancellation, lower cost of immunization overseas, and likely reductions in vaccine preventable disease-associated morbidity, we anticipate significant cost savings. Although maintaining uniform standards across diverse settings is challenging, solutions such as introduction of dedicated staff, protocol development, and ongoing technical support have ensured program cohesion, continuity, and advancement. Lessons learned can benefit similar programs implemented in the migration setting.

Setting In 2007, the US Centers for Disease Control and Prevention (CDC) revised its tuberculosis (TB) technical instructions for panel physicians who administer mandatory medical examinations among US-bound immigrants. Many US-bound immigrants come from the Philippines, a high TB prevalence country. Objective To quantify economic and health impacts of smear- vs. culture-based TB screening. Design Decision tree modeling was used to compare three Filipino screening programs: 1) no screening, 2) smear-based screening, and 3) culture-based screening. The model incorporated pre-departure TB screening results from Filipino panel physicians and CDC databases with post-arrival follow-up outcomes. Costs (2013 $US) were examined from societal, immigrant, US Public Health Department and hospitalization perspectives. Results With no screening, an annual cohort of 35 722 Filipino immigrants would include an estimated 450 TB patients with 264 hospitalizations, at a societal cost of US$9.90 million. Culture-based vs. smear-based screening would result in fewer imported cases (80.9 vs. 310.5), hospitalizations (19.7 vs. 68.1), and treatment costs (US$1.57 million vs. US$4.28 million). Societal screening costs, including US follow-up, were greater for culture-based screening (US$5.98 million) than for smear-based screening (US$3.38 million). Culture-based screening requirements increased immigrant costs by 61% (US$1.7 million), but reduced costs for the US Public Health Department (22%, US$750 000) and of hospitalization (70%, US$1 020 000). Conclusion Culture-based screening reduced imported TB and US costs among Filipino immigrants.

Histoplasmosis is known to be endemic to the Midwestern United States, but cases have been reported throughout much of the world. Somali, Hmong, and Burmese (ethnically Karen) persons make up some of the largest refugee populations coming the United States in recent years. Yet, information about risk of Histoplasma capsulatum infection amongst these populations is limited. This study used the CDC Migrant Serum Bank to test ~100 samples from each of Somali, Burmese, and Hmong U.S.-bound refugees. Samples were tested by enzyme immunoassay for Histoplasma capsulatum IgG. Overall 1% (2/299) of refugee serum samples were positive for H. capsulatum IgG. One of 99 samples obtained from Hmong refugees was positive, and the other positive sample came from among 100 Burmese refugee samples. H capsulatum IgG positivity was detected at low levels in Hmong and Burmese refugees. No IgG positivity was detected among 100 Somali refugees.

The 2014-2016 Ebola epidemic in West Africa influenced how public health officials considered migration and emerging infectious diseases. Responding to the public’s concerns, the US government introduced enhanced entry screening and post-arrival monitoring by public health authorities to reduce the risk of importation and domestic transmission of Ebola while continuing to allow travel from West Africa. This case study describes a new initiative, the Check and Report Ebola (CARE+) program that engaged travelers arriving to the United States from countries with Ebola outbreaks. The Centers for Disease Control and Prevention employed CARE ambassadors, who quickly communicated with incoming travelers and gave them practical resources to boost their participation in monitoring for Ebola. The program aimed to increase travelers’ knowledge of Ebola symptoms and how to seek medical care safely, increase travelers’ awareness of monitoring requirements, reduce barriers to monitoring, and increase trust in the US public health system. This program could be adapted for use in future outbreaks that involve the potential importation of disease and require the education and active engagement of travelers to participate in post-arrival monitoring.

During the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC implemented travel and border health measures to prevent international spread of the disease, educate and protect travelers and communities, and minimize disruption of international travel and trade. CDC staff provided in-country technical assistance for exit screening in countries in West Africa with Ebola outbreaks, implemented an enhanced entry risk assessment and management program for travelers at U.S. ports of entry, and disseminated information and guidance for specific groups of travelers and relevant organizations. New and existing partnerships were crucial to the success of this response, including partnerships with international organizations, such as the World Health Organization, the International Organization for Migration, and nongovernment organizations, as well as domestic partnerships with the U.S. Department of Homeland Security and state and local health departments. Although difficult to assess, travel and border health measures might have helped control the epidemic's spread in West Africa by deterring or preventing travel by symptomatic or exposed persons and by educating travelers about protecting themselves. Enhanced entry risk assessment at U.S. airports facilitated management of travelers after arrival, including the recommended active monitoring. These measures also reassured airlines, shipping companies, port partners, and travelers that travel was safe and might have helped maintain continued flow of passenger traffic and resources needed for the response to the affected region. Travel and border health measures implemented in the countries with Ebola outbreaks laid the foundation for future reconstruction efforts related to borders and travel, including development of regional surveillance systems, cross-border coordination, and implementation of core capacities at designated official points of entry in accordance with the International Health Regulations (2005). New mechanisms developed during this response to target risk assessment and management of travelers arriving in the United States may enhance future public health responses. The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

Air travel is an increasingly important conduit for the worldwide spread of infectious diseases. However, methods to identify which airports an individual may use to initiate travel, or where an individual may travel to upon arrival at an airport is not well studied. This knowledge gap can be addressed by estimating airport catchment areas: the geographic extent from which the airport derives most of its patronage. While airport catchment areas can provide a simple decision-support tool to help delineate the spatial extent of infectious disease spread at a local scale, observed data for airport catchment areas are rarely made publicly available. Therefore, we evaluated a probabilistic choice behavior model, the Huff model, as a potential methodology to estimate airport catchment areas in the United States in data-limited scenarios. We explored the impact of varying input parameters to the Huff model on estimated airport catchment areas: distance decay exponent, distance cut-off, and measures of airport attractiveness. We compared Huff model catchment area patterns for Miami International Airport (MIA) and Harrisburg International Airport (MDT). We specifically compared our model output to observed data sampled for MDT to align model parameters with an established, observed catchment area. Airport catchment areas derived using the Huff model were highly sensitive to changes in model parameters. We observed that a distance decay exponent of 2 and a distance cut-off of 500 km represented the most realistic spatial extent and heterogeneity of the MIA catchment area. When these parameters were applied to MDT, the Huff model produced similar spatial patterns to the observed MDT catchment area. Finally, our evaluation of airport attractiveness showed that travel volume to the specific international destinations of interest for infectious disease importation risks (i.e., Brazil) had little impact on the predicted choice of airport when compared to all international travel. Our work is a proof of concept for use of the Huff model to estimate airport catchment areas as a generalizable decision-support tool in data-limited scenarios. While our work represents an initial examination of the Huff model as a method to approximate airport catchment areas, an essential next step is to conduct a quantitative calibration and validation of the model based on multiple airports, possibly leveraging local human mobility data such as call detail records or online social network data collected from mobile devices. Ultimately, we demonstrate how the Huff model could be potentially helpful to improve the precision of early warning systems that anticipate infectious disease spread, or to incorporate when local public health decision makers need to identify where to mobilize screening infrastructure or containment strategies at a local level.

Yellow fever virus is a mosquito-borne flavivirus that causes yellow fever, an acute infectious disease that occurs in South America and sub-Saharan Africa. Most patients with yellow fever are asymptomatic, but among the 15% who develop severe illness, the case fatality rate is 20%-60%. Effective live-attenuated virus vaccines are available that protect against yellow fever (1). An outbreak of yellow fever began in Brazil in December 2016; since July 2017, cases in both humans and nonhuman primates have been reported from the states of Sao Paulo, Minas Gerais, and Rio de Janeiro, including cases occurring near large urban centers in these states (2). On January 16, 2018, the World Health Organization updated yellow fever vaccination recommendations for Brazil to include all persons traveling to or living in Espirito Santo, Sao Paulo, and Rio de Janeiro states, and certain cities in Bahia state, in addition to areas where vaccination had been recommended before the recent outbreak (3). Since January 2018, 10 travel-related cases of yellow fever, including four deaths, have been reported in international travelers returning from Brazil. None of the 10 travelers had received yellow fever vaccination.

Applying qualitative historical methods, we examined the consideration and implementation of school closures as a nonpharmaceutical intervention (NPI) in thirty US cities during the spring 2009 wave of the pA(H1N1) influenza pandemic. We gathered and performed close textual readings of official federal, state, and municipal government documents; media coverage; and academic publications. Lastly, we conducted oral history interviews with public health and education officials in our selected cities. We found that several local health departments pursued school closure plans independent of CDC guidance, that uncertainty of action and the rapidly evolving understanding of pA(H1N1) contributed to tension and pushback from the public, that the media and public perception played a significant role in the response to school closure decisions, and that there were some notable instances of interdepartmental communication breakdown. We conclude that health departments should continue to develop and fine-tune their action plans while also working to develop better communication methods with the public, and work more closely with education officials to better understand the complexities involved in closing schools. Lastly, state and local governments should work to resolve lingering issues of legal authority for school closures in times of public health crises.

The current global refugee crisis involves 65.3 million persons who have been displaced from their homes or countries of origin. While escaping immediate harm may be their first priority, displaced people go on to face numerous health risks, including trauma and injuries, malnutrition, infectious diseases, exacerbation of existing chronic diseases, and mental health conditions. This crisis highlights the importance of building capacity among health-care providers, scientists, and laboratorians to understand and respond to the health needs of refugees. The November 2016 American Society of Tropical Medicine and Hygiene (ASTMH) conference in Atlanta will feature an interactive exhibit entitled “The Refugee Journey to Wellbeing” and three symposia about refugee health. The symposia will focus on tropical disease challenges in refugee populations, careers in refugee health, and recent experiences of governmental agencies and nongovernmental organizations in responding to the global refugee crisis. We invite ASTMH attendees to attend the exhibit and symposia and consider contributions they could make to improve refugee health through tropical disease research or clinical endeavors.

Our traveler-based estimate was 2.3-fold higher than the number of laboratory-confirmed cases recorded., Using data from travelers to 4 countries in the Middle East, we estimated 3,250 (95% CI 1,300–6,600) severe cases of Middle East respiratory syndrome occurred in this region during September 2012–January 2016. This number is 2.3-fold higher than the number of laboratory-confirmed cases recorded in these countries.

HIGHLIGHT The body of knowledge needed to effectively practice travel medicine has expanded since the 1990s, as migrants begin to comprise an increasing proportion of the world's population. We describe the unique needs of migrants and provide resources available to migration health practitioners. As the number of the world's migrants grows, collaboration across disciplines is key to achieving high-quality migration health practices.

Objective: Despite increasing diversity in the US population, substantial gaps in collecting data on race, ethnicity, primary language, and nativity indicators persist in public health surveillance and monitoring systems. In addition, few systems provide questionnaires in foreign languages for inclusion of non-English speakers. We assessed (1) the extent of data collected on race, ethnicity, primary language, and nativity indicators (ie, place of birth, immigration status, and years in the United States) and (2) the use of data-collection instruments in non-English languages among Centers for Disease Control and Prevention (CDC)–supported public health surveillance and monitoring systems in the United States. Methods: We identified CDC-supported surveillance and health monitoring systems in place from 2010 through 2013 by searching CDC websites and other federal websites. For each system, we assessed its website, documentation, and publications for evidence of the variables of interest and use of data-collection instruments in non-English languages. We requested missing information from CDC program officials, as needed. Results: Of 125 data systems, 100 (80%) collected data on race and ethnicity, 2 more collected data on ethnicity but not race, 26 (21%) collected data on racial/ethnic subcategories, 40 (32%) collected data on place of birth, 21 (17%) collected data on years in the United States, 14 (11%) collected data on immigration status, 13 (10%) collected data on primary language, and 29 (23%) used non-English data-collection instruments. Population-based surveys and disease registries more often collected data on detailed variables than did case-based, administrative, and multiple-source systems. Conclusions: More complete and accurate data on race, ethnicity, primary language, and nativity can improve the quality, representativeness, and usefulness of public health surveillance and monitoring systems to plan and evaluate targeted public health interventions to eliminate health disparities.

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.

This report highlights the first two cases of MERS coronavirus in the United States. Although these patients were not transplant recipients, it is important for transplant professionals to be aware of this infection and to consider it when evaluating patients with respiratory illnesses and travel to the Arabian peninsula.

Summary Background In 2011, the Centers for Disease Control and Prevention modified its 2008 protocol for flight-related tuberculosis contact investigation initiation. The 2011 Modified protocol was implemented and replaced the 2008 CDC protocol based on comparative epidemiologic and economic analyses; this publication reports the economic analysis results. Methods A return on investment model compared relative changes in tuberculosis disease treatment costs resulting from expenditures on tuberculosis contact investigations and latent tuberculosis infection treatment for the 2008 CDC and Modified protocols. Results At moderate/high rates of latent tuberculosis infection and tuberculosis disease, positive returns on investment indicated each $1.00 spent on tuberculosis contact investigations and latent tuberculosis treatment resulted in more than $1.00 of savings from reduced tuberculosis disease treatment costs. Low rates of latent tuberculosis infection and tuberculosis disease resulted in negative returns on investment, indicating economic losses from tuberculosis disease treatment costs. There were smaller economic losses at low latent tuberculosis infection and tuberculosis disease rates with the Modified protocol in comparison to the 2008 CDC protocol, while both identified comparable numbers of persons at risk for tuberculosis. Conclusion The Modified protocol for conducting flight-related tuberculosis contact investigations represents a better use of resources and protects public health.