Demographic Characteristics and Low Iron Status Markers Are Associated with Hemoglobin Levels and Anemia among Children Living at High Elevation in Cusco, Peru

Anemia is a complex condition associated with diet, chronic infections, and blood loss. Children living at high altitudes have higher absolute hemoglobin levels due to hypoxemia. However, they are exposed to repeated infections and dietary limitations. We conducted a cross-sectional study to identify factors affecting the hemoglobin concentration in children living in high-altitude rural communities in the Anta province of Peru. All children 3-16 years of age attending public schools were invited to participate. We enrolled children 3-16 years old in schools and visited their homes to collect demographic, socioeconomic, medical history, and anthropometric data. Children provided blood and stool samples for complete blood counts, iron status markers, and helminth infection testing. Among the 2,000 children enrolled, the mean age was 9.9 (±3.4) years, 1,004 (50.2%) were female, and the median residence altitude was 3,398 (interquartile range 3,35-3,497) meters. The mean hemoglobin level was 15 (±1.15) mg/dL; 320 (16%) had anemia as defined by WHO. Children with anemia were more likely to have lower serum iron levels (odds ratio [OR] 2.8 [95% CI 2.2-3.6], P <0.001) and serum transferrin saturation (OR 2.8 [95% CI 2-3.9], P <0.001). Younger age (OR 0.85 [95% CI 0.82-0.89], P <0.001), stunting (OR 0.68 [95% CI 0.59-0.79], P <0.001), education of the mother (OR 0.94 [95% CI 0.91-0.98], P <0.005), and low eosinophils (OR 0.49 [95% CI 0.26-0.9], P = 0.022) were associated with anemia. Helminth infections were not associated with anemia. Anemia among children at high altitude is multifactorial, but iron deficiency is a contributing factor. Further studies are needed to evaluate iron status and anemia in children living at high altitudes.

An Update on the Pathogenesis of Fascioliasis: What Do We Know?

Fasciola hepatica is a trematode parasite distributed worldwide. It is known to cause disease in mammals, producing significant economic loses to livestock industry and burden to human health. After ingestion, the parasites migrate through the liver and mature in the bile ducts. A better understanding of the parasite's immunopathogenesis would help to develop efficacious therapeutics and vaccines. Currently, much of our knowledge comes from in vitro and in vivo studies in animal models. Relatively little is known about the host-parasite interactions in humans. Here, we provide a narrative review of what is currently know about the pathogenesis and host immune responses to F. hepatica summarizing the evidence available from the multiple hosts that this parasite infects.

Causes of death among international travellers in Peru, 2017 to 2021

BACKGROUND

The wellbeing and safety of international tourists is a paramount concern for governments and stakeholders. Mortality among travellers and the causes of death serve as a significant metric of destination safety. We describe the epidemiology and causes of death among international travellers in Peru.

METHODS

Data retrieved from the Peruvian government's deaths certificates registry included all non-residents who died between January 2017 and December 2021. We analysed the national incidence and causes of death among international travellers in Peru. Causes of death were classified into non-communicable diseases (NCD), communicable diseases and injuries. We classified fatalities according to the existence of preventive measures that could be provided during the travel medicine consultation to decrease the risk.

RESULTS

We obtained records from 1514 deaths among international travellers (973 males, 64%). The incidence increased from 0.2 deaths per 10 000 travellers in 2017 to 9.9 in 2021. NCDs were the most common causes of death (n = 560, 37%), followed by communicable diseases (n = 487, 32%), and injuries (n = 321, 21%). Causes of death were unknown in 9.7% of the records. The leading causes of death in these categories were cancer, cardiovascular disease, COVID-19 and trauma. We found similar sex distribution of NCDs in travellers aged >50 years and higher rates of communicable diseases among males across all ages. Injury-associated deaths were significantly higher among males aged 18-29 years (P < 0.001) compared with other sex-age groups. We estimated that for 57.7% of deaths risk could have been decreased through pre-travel advice.

CONCLUSION

Rates of deaths among travellers to Peru increased over time. Most deaths were due to NCDs, followed by communicable diseases and injuries. Pre-travel medical optimization and effective advice focused on age-sex and destination specific risks could reduce risk among travellers. Increased awareness among travel medicine practitioners and improvement of emergency medical response systems in Peru could decrease mortality.

Etiological characterization of acute undifferentiated febrile illness in Apartadó and Villeta municipalities, Colombia, during COVID-19 pandemic

Background

Acute undifferentiated febrile illness (AUFI) is one of the leading causes of illness in tropical regions. Although malaria is the most important cause, other pathogens such as Dengue (DENV), Leptospira and recently, Coronavirus Disease 2019 (COVID-19) have gained importance. In Colombia, few studies aimed to identify the etiology of AUFI. Most of them performed in Apartadó and Villeta municipalities, identifying the active circulation of several pathogens. Thus, we conducted a cross-sectional study in these municipalities to characterize the etiologies of AUFI during COVID-19 pandemic.

Methods

An active surveillance was conducted between September and December 2021 in local hospitals of Apartadó and Villeta municipalities. Febrile patients were enrolled after voluntarily agreeing to participate in the study. Ten different etiologies were evaluated through direct, serological, molecular and rapid diagnostic methods.

Results

In Apartadó a confirmed etiology was found in 60% of subjects, DENV (25%) being the most frequent, followed by leptospirosis (16.7%), malaria (10%), COVID-19 (8.3%), spotted fever group (SFG) rickettsiosis (6.7%) and Chikungunya (1.7%). In Villeta, a specific etiology was confirmed in 55.4% of patients, of which SFG rickettsiosis (39.3%) was the most frequent, followed by leptospirosis (21.4%), DENV (3.6%) and malaria (1.8%). No cases due to Mayaro, Yellow Fever, Oropouche and Venezuelan Equine Encephalitis viruses were detected.

Conclusion

We confirm the relevance of dengue fever, leptospirosis, SFG rickettsiosis, COVID-19 and malaria as causes of AUFI in the municipality of Apartadó, and highlight the great importance of SFG rickettsiosis as the main cause of AUFI in the municipality of Villeta.

Nasopharyngeal Myiasis in Intensive Care Unit (ICU) Patients: Report of Two Cases

Nosocomial myiasis is a rare event that has a higher incidence in the hospitals of poor and developing countries. The presence of nosocomial myiasis reflects the need for improved medical facilities and increased awareness among healthcare personnel. Severely ill patients are more susceptible, such as those with impaired consciousness, paralysis, and underlying diseases. The two cases here in described represent the first report of nosocomial myiasis in the Kurdistan Province, in Western Iran and one of them is the first report of myiasis involving a COVID-19-infected patient. The causal agent was Lucilia sericata. The taxonomical identification of the larvae of the second and third instar was based on the morphology of the cephaloskeleton, anterior spiracles, and peritreme plaques.

Risk factors for acute mountain sickness in travellers to Cusco, Peru: coca leaves, obesity and sex

BACKGROUND

Acute mountain sickness (AMS) may occur after rapid ascents to altitudes >2500 m. Cusco (3350 m) in Peru is a popular destination for altitude inexperienced travellers. This study aimed at evaluating the incidence and risk factors for AMS among a cohort of foreign Spanish language students in Cusco.

METHODS

We performed a cohort study among young healthy foreign Spanish language students arriving to Cusco between 2012 and 2016. Consenting students answered an enrollment questionnaire on demographics, travel history and intended AMS preventive behaviour within 48 h of arrival. At 4-5 days after enrollment participants answered a second questionnaire about actual preventive behaviour before symptoms and the development of symptoms compatible with AMS during their first 48 h in Cusco. We used the 2018 Lake Louise Scoring System for AMS diagnosis. Participants with headache and a score ≥ 3 were considered to have AMS.

RESULTS

We enrolled 142 language students, the median age was 21 years (interquartile range 20-25) and 57% were female. Participants decreased physical activity (38%), increased fluid intake (34%), drank coca leaf tea (34%), took acetazolamide (16%) and acclimatized at a lower altitude (6%) to prevent AMS. Thirty-nine percent had AMS. In the multivariate analysis, obesity [odds ratio (OR) 14.45 (2.33-89.6)] and female sex [OR 4.32 (1.81-10.28)] were associated with increased risk of AMS. Taking acetazolamide [OR 0.13 (0.03-0.56)] was associated with decreased AMS risk. Consumption of coca leaf tea was not associated with decreased risk of AMS.

CONCLUSIONS

In our cohort, AMS affected two out of five travellers. Obesity and female sex were associated with increased risk. Drinking coca leaf tea for prevention did not decrease the risk of AMS. Acetazolamide prophylaxis was associated with decreased risk of AMS.

The Differences in the Susceptibility Patterns to Triclabendazole Sulfoxide in Field Isolates of Fasciola hepatica Are Associated with Geographic, Seasonal, and Morphometric Variations

Triclabendazole (TCBZ) resistance is an emerging problem in fascioliasis that is not well understood. Studies including small numbers of parasites fail to capture the complexity of susceptibility variations between and within Fasciolahepatica populations. As the first step to studying the complex resistant phenotype−genotype associations, we characterized a large sample of adult F. hepatica with diverging TCBZ susceptibility. We collected parasites from naturally infected livestock slaughtered in the Cusco and Cajamarca regions of Peru. These parasites were exposed to TCBZ sulfoxide (TCBZ.SO) in vitro to determine their susceptibility. We used a motility score to determine the parasite’s viability. We titrated drug concentrations and times to detect 20% non-viable (susceptible conditions) or 80% non-viable (resistant conditions) parasites. We exposed 3348 fully motile parasites to susceptible (n = 1565) or resistant (n = 1783) conditions. Three hundred and forty-one (21.8%) were classified as susceptible and 462 (25.9%) were classified as resistant. More resistant parasites were found in Cusco than in Cajamarca (p < 0.001). Resistant parasites varied by slaughterhouse (p < 0.001), month of the year (p = 0.008), fluke length (p = 0.016), and year of collection (p < 0.001). The in vitro susceptibility to TCBZ.SO in wildtype F. hepatica was associated with geography, season, and morphometry.

A Comparison of the Risk for Chronic Fascioliasis between Children 3 to 5 Years and Children 6 to 12 Years of Age in the Cusco Region of Peru

School-age children bear the highest burden of fascioliasis in endemic countries. Few studies have addressed Fasciola in preschool children. We performed a secondary data analysis using two Fasciola databases from Cusco, Peru, comparing preschoolers with elementary school children. We included 2,630 children, 50% were female, the median age was 8.4 years (interquartile range [IQR] 6.1-10.5), and 15% (396/2,630) were < 5 years of age. Children < 5 years were less likely to be infected with Fasciola hepatica (P = 0.008) and Hymenolepis nana (P < 0.001) and more likely to have anemia (P < 0.001) and a lower median height for age Z (HAZ) score (P = 0.002). Fascioliasis was less common in younger children, but this group may be at higher risk for chronic complications caused by fascioliasis.

Triclabendazole Treatment Failure for Fasciola hepatica Infection among Preschool and School-Age Children, Cusco, Peru1

We conducted a retrospective cohort study of children who had chronic fascioliasis in the highlands of Peru to determine triclabendazole treatment efficacy. Children passing Fasciola eggs in stool were offered directly observed triclabendazole treatment (>1 doses of 10 mg/kg). Parasitologic cure was evaluated by using microscopy of stool 1–4 months after each treatment. A total of 146 children who had chronic fascioliasis participated in the study; 53% were female, and the mean ± SD age was 10.4 ± 3.1 years. After the first treatment, 55% of the children achieved parasitologic cure. Cure rates decreased after the second (38%), third (30%), and fourth (23%) treatments; 17 children (11.6%) did not achieve cure after 4 treatments. Higher baseline egg counts and lower socioeconomic status were associated with triclabendazole treatment failure. Decreased triclabendazole efficacy in disease-endemic communities threatens control efforts. Further research on triclabendazole resistance and new drugs to overcome it are urgently needed.

Stunting in pre-school and school-age children in the Peruvian highlands and its association with Fasciola infection and demographic factors

Fascioliasis is a zoonotic trematode infection that is endemic in the highlands of Peru. Chronic fascioliasis can be asymptomatic and remain undiagnosed for years. Chronic malnutrition in children, as manifested by stunting, leads to delayed cognitive development and lost productivity. We hypothesized that fascioliasis is among the factors associated with stunting in children from endemic areas. We conducted a cross-sectional study among children attending pre-school and school in 26 communities in the Anta province in the Cusco region of Peru. We conducted interviews to collect information on demographic, socioeconomic, and medical history. Blood was collected and tested for complete cell count and FAS2 ELISA for Fasciola antibodies. Three stool samples per participant were tested for parasites by Kato-Katz and Lumbreras rapid sedimentation methods. Chronic fascioliasis was determined by the presence of ova in stool. Children's height, weight, and age were recorded and used to calculate height for age Z scores (HAZ). Three thousand children participated in the study. Nine percent (264) of children had at least one positive test for Fasciola infection, 6% (164) had chronic fascioliasis, and 3% (102) had only positive antibody tests. The median HAZ was -1.41 (IQR: -2.03 to -0.81) and was similar in males and females. Twenty six percent (776) of children had stunting with HAZ < -2. Children with chronic fascioliasis had a lower median HAZ than children without Fasciola (-1.54 vs. -1.4, p = 0.014). History of treatment for malnutrition, history of treatment for anemia, having other helminths in stool, lower socioeconomic score, living at a higher elevation, and fewer years of schooling of both parents were associated with a lower HAZ score. In a multiple regression analysis, older age and a lower socioeconomic score were associated with a lower HAZ score. While fascioliasis and other helminths were associated with lower HAZ, they were not independent of the socioeconomic score.

Fasciola hepatica Infection Risk for Adult Household Members with Children with Fascioliasis in Cusco, Peru

Fasciola hepatica is highly prevalent in the highlands of Peru. School-age children have the greatest risk of infection. Mass treatment of at-risk populations has been proposed to control the infection and prevent complications. However, the decreasing effectiveness of triclabendazole raises concerns regarding this strategy. Previous studies reported aggregation of Fasciola infection among family members. This study aimed to determine the risk of fascioliasis among household members living with Fasciola-infected children identified through school-based testing. We conducted a cross-sectional study including adult members of households where children with and without fascioliasis were identified. Demographic, epidemiological, and socioeconomic information was collected. One blood sample was drawn to test for Fasciola antibodies, and three stool samples were collected for microscopy for Fasciola ova. We tested 326 adults from 213 households. Of these adult subjects, chronic fascioliasis (24 of 326, 7.4%) was the most common helminth infection. Thirty-nine subjects (12.7%) tested positive for Fasciola antibodies. Combining microscopy and serum antibody tests, 13.2% (43 of 326) had evidence of Fasciola infection. One third (104 of 326, 31.9%) of the participants lived with at least one child infected with Fasciola hepatica. Adults with fascioliasis were four times more likely to live with an infected child. Poverty and diet were associated with increased risk of Fasciola infection. Adults with fascioliasis were significantly more likely to live with Fasciola-infected children.

Stunting Is Preceded by Intestinal Mucosal Damage and Microbiome Changes and Is Associated with Systemic Inflammation in a Cohort of Peruvian Infants

Stunting, defined as height-for-age Z score equal to or lower than -2, is associated with increased childhood mortality, cognitive impairment, and chronic diseases. The aim of the study was to investigate the relationship between linear growth, intestinal damage, and systemic inflammation in infants at risk of stunting. We followed up 78 infants aged 5-12 months living in rural areas of Peru for 6 months. Blood samples for biomarkers of intestinal damage (intestinal fatty-acid-binding protein [I-FABP] and zonulin) and systemic inflammation (interleukin-1β, interleukin-6, tumor necrosis factor α [TNF-α], soluble CD14, and lipopolysaccharide-binding protein [LBP]) and fecal samples for microbiome analysis were collected at baseline and closure of the study. The children's growth and health status were monitored through biweekly home visits by trained staff. Twenty-one percent of the children became stunted: compared with non-stunted children, they had worse nutritional parameters and higher levels of serum I-FABP at baseline. The likelihood of becoming stunted was strongly associated with an increase in sCD14 over time; LBP and TNF-α showed a trend toward increase in stunted children but not in controls. The fecal microbiota composition of stunted children had an increased beta diversity compared with that of healthy controls throughout the study. The relative abundance of Ruminococcus 1 and 2, Clostridium sensu stricto, and Collinsella increased in children becoming stunted but not in controls, whereas Providencia abundance decreased. In conclusion, stunting in our population was preceded by an increase in markers of enterocyte turnover and differences in the fecal microbiota and was associated with increasing levels of systemic inflammation markers.

Adaptive Radiation of the Flukes of the Family Fasciolidae Inferred from Genome-Wide Comparisons of Key Species

Liver and intestinal flukes of the family Fasciolidae cause zoonotic food-borne infections that impact both agriculture and human health throughout the world. Their evolutionary history and the genetic basis underlying their phenotypic and ecological diversity are not well understood. To close that knowledge gap, we compared the whole genomes of Fasciola hepatica, Fasciola gigantica, and Fasciolopsis buski and determined that the split between Fasciolopsis and Fasciola took place ∼90 Ma in the late Cretaceous period, and that between 65 and 50 Ma an intermediate host switch and a shift from intestinal to hepatic habitats occurred in the Fasciola lineage. The rapid climatic and ecological changes occurring during this period may have contributed to the adaptive radiation of these flukes. Expansion of cathepsins, fatty-acid-binding proteins, protein disulfide-isomerases, and molecular chaperones in the genus Fasciola highlights the significance of excretory-secretory proteins in these liver-dwelling flukes. Fasciola hepatica and Fasciola gigantica diverged ∼5 Ma near the Miocene-Pliocene boundary that coincides with reduced faunal exchange between Africa and Eurasia. Severe decrease in the effective population size ∼10 ka in Fasciola is consistent with a founder effect associated with its recent global spread through ruminant domestication. G-protein-coupled receptors may have key roles in adaptation of physiology and behavior to new ecological niches. This study has provided novel insights about the genome evolution of these important pathogens, has generated genomic resources to enable development of improved interventions and diagnosis, and has laid a solid foundation for genomic epidemiology to trace drug resistance and to aid surveillance.

Socioeconomic Factors Associated with Fasciola hepatica Infection Among Children from 26 Communities of the Cusco Region of Peru

Fasciola hepatica is the most widely distributed trematode-affecting humans. The Andes Mountains are highly endemic for fascioliasis. We report results of a cross-sectional study evaluating the epidemiology of Fasciola among children in 26 agricultural communities in the Cusco region of Peru. Children 3 to 16 years old were enrolled in preschools and schools. Blood from participants was tested for complete blood counts, transaminases, and Fasciola antibodies. Stool samples were tested for Fasciola and other parasites. A total of 2,515 children were included in the analysis and the mean age was 9.6 years (±3.6). Ten percent (253) of the children had at least one positive test for Fasciola, 6% had chronic infection, and 0.4% acute infection. The rest of the subjects had only antibodies against Fasciola. The prevalence of infection varied from 0% to 20% between communities. Children with evidence of Fasciola exposure were older, lived at higher altitudes, and had a lower socioeconomic status than children without infection. The logistic regression analysis showed that children from Ancahuasi district, older children, and children with higher measures of poverty were more likely to have Fasciola exposure. Fascioliasis is common in the Cusco region and associated with poverty. However, the distribution varies markedly between communities.

Intestinal cestodes

PURPOSE OF REVIEW

Cestodes infections in humans are among the most prevalent parasitosis worldwide. Although tapeworm infection is often asymptomatic, they can be associated with a range of symptoms. The landscape of cestode infections is changing with rapid diagnosis techniques and advanced molecular diagnosis aiding in identification of species specific epidemiology.

RECENT FINDINGS

Traditional descriptions of species by location have been challenged with molecular diagnostic techniques, which show variation in distribution of species, thought to be because of globalization and importation of disease.

MAIN THEMES IN LITERATURE

Epidemiology, molecular diagnostic techniques.

SUMMARY

Infection by tapeworms is often asymptomatic or accompanied by mild symptoms though can occasionally cause severe disease and contribute to anemia and malnutrition. Tapeworm infection is most prevalent in resource-poor countries but the distribution is worldwide. Epidemiology of infection is changing because of molecular diagnostics, which allow more accurate tracking of species.

Prevalence and Risk Factors for Human Cystic Echinococcosis in the Cusco Region of the Peruvian Highlands Diagnosed Using Focused Abdominal Ultrasound

AbstractLatin America is among the highly endemic regions for cystic echinococcosis (CE). In Peru, an estimated 1,139 disability-adjusted life years are lost annually from surgical treatment of CE. This is comparable with the combined total for Argentina, Brazil, Uruguay, and Chile. The prevalence of human infection has been investigated in the central Peruvian Andes, but there are no community-based screening data from other regions of Peru. We carried out a population survey in January 2015 using abdominal ultrasound to estimate the prevalence of abdominal CE in the Canas and Canchis provinces, in the Cusco region of Peru. Among 1,351 subjects screened, 41 (3%) had CE. There was significant variation between communities with similar socioeconomic features in a small geographical area. A history of CE was reported by 4.1% of the screened subjects, among whom 30.3% still had CE on ultrasound. Among patients reporting previous CE treatment, 14.9% had CE in active stages. Limited education, community of residence, and knowing people with CE in the community were associated with CE. These results demonstrate a significant burden of CE in the region and suggest the need for further investigations, control activities, and optimization of clinical management for CE in this area.

Case-Case Analysis Using 7 Years of Travelers' Diarrhea Surveillance Data: Preventive and Travel Medicine Applications in Cusco, Peru

AbstractIn Cusco, Peru, and South America in general, there is a dearth of travelers' diarrhea (TD) data concerning the clinical features associated with enteropathogen-specific infections and destination-specific risk behaviors. Understanding these factors would allow travel medicine providers to tailor interventions to patients' risk profiles and travel destination. To characterize TD etiology, evaluate region-specific TD risk factors, and examine relationships between preventive recommendations and risk-taking behaviors among medium- to long-term travelers' from high-income countries, we conducted this case-case analysis using 7 years of prospective surveillance data from adult travelers' presenting with TD to a physician in Cusco. At the time of enrollment, participants provided a stool sample and answered survey questions about demographics, risk behaviors, and the clinical features of illness. Stool samples were tested for norovirus (NV), bacteria, and parasites using conventional methods. Data obtained were then analyzed using case-case methods. NV (14%), enterotoxigenic Escherichia coli (11%), and Campylobacter (9%), notably ciprofloxacin-resistant Campylobacter, were the most frequently identified pathogens among adults with TD. Coinfection with multiple enteropathogens occurred in 5% of cases. NV caused severe disease relative to other TD-associated pathogens identified, confining over 90% of infected individuals to bed. Destination-specific risk factors include consumption of the local beverage "chicha," which was associated with Cryptosporidium infection. Preventive interventions, such as vaccines, directed against these pathogens could significantly reduce the burden of TD.

Recombinase Polymerase Amplification Compared to Real-Time Polymerase Chain Reaction Test for the Detection of Fasciola hepatica in Human Stool

Fasciola hepatica is the most widely distributed trematode infection in the world. Control efforts may be hindered by the lack of diagnostic capacity especially in remote endemic areas. Polymerase chain reaction (PCR)-based methods offer high sensitivity and specificity but require expensive technology. However, the recombinase polymerase amplification (RPA) is an efficient isothermal method that eliminates the need for a thermal cycler and has a high deployment potential to resource-limited settings. We report on the characterization of RPA and PCR tests to detect Fasciola infection in clinical stool samples with low egg burdens. The sensitivity of the RPA and PCR were 87% and 66%, respectively. Both tests were 100% specific showing no cross-reactivity with trematode, cestode, or nematode parasites. In addition, RPA and PCR were able to detect 47% and 26% of infections not detected by microscopy, respectively. The RPA adapted to a lateral flow platform was more sensitive than gel-based detection of the reaction products. In conclusion, the Fasciola RPA is a highly sensitive and specific test to diagnose chronic infection using stool samples. The Fasciola RPA lateral flow has the potential for deployment to endemic areas after further characterization.

Hymenolepis nana Impact Among Children in the Highlands of Cusco, Peru: An Emerging Neglected Parasite Infection

Hymenolepis nana is the most common cestode infection in the world. However, limited information is available regarding its impact on affected populations. We studied the epidemiology and symptoms associated with hymenolepiasis among children 3-16 years old in 16 rural communities of the highlands of the Cusco region in Peru. Information on demographics, socioeconomic status, symptoms as reported by parents, and parasitological testing was obtained from the database of an ongoing Fasciola hepatica epidemiologic study. A total of 1,230 children were included in the study. Forty-five percent were infected with at least one pathogenic intestinal parasite. Giardia spp. (22.9%) was the most common, followed by Hymenolepis (17.4%), Fasciola (14.1%), Ascaris lumbricoides (6.1%), and Strongyloides stercoralis (2%). The prevalence of Hymenolepis infection varied by community, by other parasitic infections, and by socioeconomic status. However, only years of education of the mother, use of well water, and age less than 10 years were associated with Hymenolepis infection in the multivariate analysis. Hymenolepis nana infection was associated with diarrhea, jaundice, headaches, fever, and fatigue. Children with > 500 eggs/g of stool were more likely to have symptoms of weight loss, jaundice, diarrhea, and fever. Hymenolepis nana infection and age were the only factors retained in the multivariate analysis modeling diarrhea. Hymenolepiasis is a common gastrointestinal helminth in the Cusco region and is associated with significant morbidity in children in rural communities. The impact caused by the emergence of Hymenolepis as a prevalent intestinal parasite deserves closer scrutiny.

Fasciola hepatica Infection in an Indigenous Community of the Peruvian Jungle

Fasciola hepatica is a zoonotic infection with a worldwide distribution. Autochthonous cases have not been reported in the Amazon region of Peru. Operculated eggs resembling F. hepatica were identified in the stools of five out of 215 subjects in a remote indigenous community of the Peruvian jungle. Polymerase chain reaction targeting Fasciola hepatica cytochrome oxidase subunit 1 (COI) gene and sequencing of the products confirmed Fasciola infection.

Treatment Failure after Multiple Courses of Triclabendazole among Patients with Fascioliasis in Cusco, Peru: A Case Series

Triclabendazole is reported to be highly effective in treatment of human fascioliasis. We present 7 of 19 selected cases of human fascioliasis referred to our center in the Cusco region of Peru that failed to respond to triclabendazole. These were mostly symptomatic adults of both sexes that continued passing Fasciola eggs in the stool despite multiple treatments with 2 doses of triclabendazole at 10 mg/kg per dose. We documented the presence of eggs by rapid sedimentation and Kato Katz tests after each treatment course. We found that repeated triclabendazole courses were not effective against fascioliasis in this group of people. These findings suggest that resistance to triclabendazole may be an emerging problem in the Andes.

Fascioliasis is a zoonotic food borne trematode infection with a wide distribution. The complex epidemiology of this infection makes control efforts difficult. The paucity of drugs available for treatment may further hinder their success. Triclabendazole, the only first line drug for Fasciola, has been used for many years in the livestock industry. Resistant livestock Fasciola infections have emerged in developing and developed countries. However, most human trials report triclabendazole efficacies close to 100% after a few doses. Only a few cases of triclabendazole treatment failure have been published. We document 7 patients infected with Fasciola hepatica in Cusco–Peru that failed several treatment courses with triclabendazole. This raises concerns regarding preparedness to address resistant parasite infections and calls for more research to find new medications and tools to evaluate resistance.

[Massive hookworm infection as a cause of intestinal bleeding and severe anemia]

Overt gastrointestinal bleeding caused by hookworm infection is rarely reported. We present a 34 year old male with lower gastrointestinal bleeding with evidence of massive hookworm infection on colonoscopy and discuss the need to consider hookworm infection as a possible etiology of gastrointestinal bleed in endemic areas.

Prevalence of intestinal helminths, anemia, and malnutrition in Paucartambo, Peru

OBJECTIVE

To evaluate the prevalence of soil-transmitted helminth infections, anemia, and malnutrition among children in the Paucartambo province of Cusco region, Peru, in light of demographic, socio-economic, and epidemiologic contextual factors.

METHODS

Children from three to twelve years old from six communities in Huancarani district in the highlands of Peru were evaluated for helminth infections, anemia, and nutritional status. Data collected included demographic variables, socioeconomic status, exposures, complete blood counts, and direct and sedimentation stool tests.

RESULTS

Of 240 children analyzed, 113 (47%) were infected with one or more parasites. Giardia (27.5%) and Fasciola (9.6%) were the most commonly identified organisms. Eosinophilia was encountered in 21% of the children. Anemia (48.8%) was associated with age (3-4 vs 5-12 years old; odds ratio (OR): 5.86; 95% confidence interval (CI): 2.81-12.21). Underweight (10%) was associated with male sex (OR: 5.97; CI: 1.12-31.72), higher eosinophil count (OR: 4.67; CI: 1.31-16.68) and education of the mother (OR: 0.6; CI: 0.4-0.9). Stunting (31.3%) was associated with education of the mother (OR: 0.83; CI: 0.72-0.95); wasting (2.7%) was associated with higher eosinophil count (OR: 2.75; CI: 1.04-7.25).

CONCLUSIONS

Anemia and malnutrition remain significant problems in the Peruvian highlands. These findings suggest that demographic factors, socio-economic status, and possibly parasitic infections intertwine to cause these health problems.

[Disseminated cutaneous sporotrichosis with joint involvement in a woman with type 2 diabetes]

Disseminated sporotrichosis is a rare presentation of this mycosis. Although it has been described in immunocompetent individuals, there is often T cell-mediated immune compromise. We report the case of a woman with uncontrolled Type 2 diabetes who developed disseminated cutaneous sporotrichosis. The course of the disease presented several complications including hepatitis secondary to itraconazole and knee arthritis with culture positive for Sporothrix schenckii during treatment with saturated solution of potassium iodide. The case discussion includes aspects of the pathogenesis of disseminated sporotrichosis and management of the infection and its complications.

Advice on malaria and yellow fever prevention provided at travel agencies in Cuzco, Peru

BACKGROUND

Travelers receive medical advice from a variety of sources, including travel agencies. The aim of this study is to describe the quality of pre-travel advice provided by travel agencies in Cuzco to travelers interested in visiting malaria and yellow fever endemic areas.

METHODS

Trained medical students posed as tourists and visited travel agencies in Cuzco requesting travel advice for a trip to the southern Amazon of Peru, recording advice regarding risk and prevention of malaria and yellow fever.

RESULTS

A total of 163 registered travel agencies were included in the study. The mean proposed tour duration was 6.8 days (±1.4 days) with a median time to departure of 3 days and a median tour cost of 805 US dollars (USD) [interquartile range (IQR) 580-1,095]. Overall, 45% employees failed to mention the risk for any illness. Eighteen percent of the employees acknowledged risk of malaria and 53% risk of yellow fever. However, 36% denied malaria risk and 2% denied risk of yellow fever in the region. The price of tours from travel agencies that did not mention any health risk was significantly lower [1,009.6 ± 500.5 vs 783.9 ± 402 USD, t (152) = 3, p < 0.01] compared with the price from agencies that did mention health risks. Almost all who acknowledged malaria (97%) and/or yellow fever (100%) were able to provide at least one recommendation for prevention. However, advice was not always accurate or spontaneously volunteered. Only 7% of the employees provided both correct scheduling and location information for administration of the yellow fever vaccine.

CONCLUSIONS

The majority of registered travel agencies in Cuzco did not provide sufficient and accurate information regarding risk and prevention of malaria and yellow fever to travelers inquiring about trips to the southern Amazon of Peru.

Fascioliasis and eosinophilia in the highlands of Cuzco, Peru and their association with water and socioeconomic factors

There are limited data about the epidemiology of fascioliasis in Cuzco, Peru. We studied children 3-12 years old from six communities in the highlands of Cuzco to evaluate the epidemiology of fascioliasis; 227 children were included, one-half were female, the mean age was 7.5 (±2.6) years, and 46.2±% had one or more parasites, including Fasciola (9.7%), Ascaris (12.8%), Hymenolepis (9.3%), Trichuris (1.3%), hookworm (1.8%), Strongyloides (0.9%), and Giardia (27.8%). Fasciola was associated with the number of siblings in the household, drinking untreated water, and giardiasis. Eosinophilia was encountered in 21% of children and more common in those drinking untreated water at home and those infected with a parasite, but the differences were not significant. Eating water plants was not associated with Fasciola or eosinophilia. Fascioliasis and eosinophilia were common in the highlands of Cuzco. Fascioliasis was associated with socioeconomic factors and drinking water.

Prevalence of soil-transmitted helminths after mass albendazole administration in an indigenous community of the Manu jungle in Peru

Few data are available on the epidemiology of soil-transmitted helminths (STHs) in indigenous populations of the Peruvian Amazon. While albendazole is being increasingly used in deworming campaigns, few data exist on the impact of mass drug administration in isolated populations. We studied the prevalence of STHs, anemia, and malnutrition in a Matsigenka ethnic group from the Peruvian Amazon. Participants had received two doses of albendazole on consecutive days, 3 months before and again 2 weeks before data collection. Overall, 290 subjects were included. Most were female (53.7%) and 63.9% were ≤19 years old. Half of the participants had helminth infections. Trichiuris (30.2%), hookworm (19.1%), Ascaris (17.7%), and Strongyloides (5.6%) were the most common helminths. Other helminth ova included Capillaria hepatica and Fasciola-like eggs. Subjects of 5-19 years (51.8 %) and 20-35 years (68.6 %) old had helminths more often than those under 5 years (38%) and older than 35 years (41.5%) (P  =  0.02). Anemia was detected in 41% of children and this was more common in children under 5 years that in those of 5-19 years [odd ratio (OR) = 5.68; 95% CI: 2.71-11.88]. Overall, 72.1% of children were malnourished. Stunting was common in children (70.7%), but wasting was not (2.9%). Despite repeated albendazole administration, this population continued to have a high prevalence of STHs, anemia, and malnutrition. In addition, we detected unusual organisms and organisms that do not respond to albendazole. Further studies are needed to assess the rationale and efficacy of mass chemotherapy for STHs in the Amazon.

Treatable bacterial infections are underrecognized causes of fever in Ethiopian children

Febrile illnesses remain a major cause of morbidity and mortality in resource-poor countries, but too often, tests are not available to determine the causes, leading to misdiagnosis and inappropriate treatment. To determine the cause of febrile illnesses, we recovered the malaria smears from 102 children presenting with fever to Soddo Christian Hospital in Wolaitta Soddo, Ethiopia. DNA was isolated from the smears and evaluated by real-time polymerase chain reaction. We identified pathogen DNA with probes for Plasmodium spp., Streptococcus pneumoniae, Rickettsia spp., Salmonella spp., and Borrelia spp. Overall, we showed that it is possible to isolate high-quality DNA and identify treatable pathogens from malaria blood smears. Furthermore, our data showed that bacterial pathogens (especially Pneumococcus, Rickettsia spp., and Borrelia spp.) are common and frequently unrecognized but treatable causes of febrile illnesses in Ethiopian children.

Acute mountain sickness impact among travelers to Cusco, Peru

BACKGROUND

Increasing numbers of travelers are visiting high altitude locations in the Andes. The epidemiology of acute mountain sickness (AMS) among tourists to high altitude in South America is not well understood.

METHODS

A cross-sectional study to evaluate the epidemiology, pre-travel preparation, and impact of AMS among travelers to Cusco, Peru (3,400 m) was performed at Cusco's International Airport during June 2010. Foreign travelers, 18 years or older, staying 15 days or less, departing Cusco were invited to participate. Demographic, itinerary, and behavioral data were collected. The Lake Louise Clinical score (LLCS) was used to assess AMS symptoms.

RESULTS

In total, 991 travelers participated, median age 32 years (interquartile range 25-49), 55.5% female, 86.7% tourists, mostly from the United States (48.2%) and England (8.1%). Most (76.7%) flew from sea level to Cusco and 30.5% visited high altitude in the previous 2 months. Only 29.1% received AMS advice from a physician, 19% recalled advice on acetazolamide. Coca leaf products (62.8%) were used more often than acetazolamide (16.6%) for prevention. AMS was reported by 48.5% and 17.1% had severe AMS. One in five travelers with AMS altered their travel plans. Travelers older than 60 years, with recent high altitude exposure, who visited lower cities in their itinerary, or used acetazolamide were less likely to have AMS. Using coca leaf products was associated with increased AMS frequency.

CONCLUSIONS

AMS was common and adversely impacted plans of one in five travelers. Acetazolamide was associated with decreased AMS but was prescribed infrequently. Other preventive measures were not associated with a decrease in AMS in this population. Pre-travel preparation was suboptimal.

Burden of Fasciola hepatica Infection among children from Paucartambo in Cusco, Peru

There is a high prevalence of fascioliasis in the Peruvian highlands, but most cases remain undiagnosed. The burden of disease caused by chronic subclinical infection is largely unknown. We studied school-age children from a district in Paucartambo Province in Cusco, Peru to evaluate the burden of disease caused by subclinical fascioliasis. Parasite eggs and/or larvae were identified in 46.2% of subjects, including Fasciola hepatica in 10.3% of subjects. Fascioliasis was independently associated with anemia (adjusted odds ratio = 3.01 [1.10-8.23]). Subclinical fascioliasis was common among children and strongly associated with anemia. Anemia should be recognized as an important component of the burden of disease from fascioliasis.

Pre-travel preparation for Cusco, Peru: a comparison between European and North American travelers

BACKGROUND

Demographics, preferences on health care, and regional differences in pre-travel advice guidelines may influence the preparation of travelers to developing countries.

METHODS

A secondary data analysis of the database of a travelers' health survey conducted in Cusco in 2002 was performed. Data from those whose place of residence was North America or Western Europe were selected. Illness rates, vaccinations, prophylactic medication use, and general recommendations on disease prevention were compared between the two groups.

RESULTS

Data from 1,612 North Americans (NAM) and 3,590 Western Europeans (EUR) were analyzed. NAM were older, stayed longer in Cusco, and had less experience traveling to developing countries (p < 0.01). They reported being ill more often than EUR (58% vs 42%, p < 0.01). Diarrhea was more frequent among EUR (55.6% vs 46.7%, p < 0.01), and acute mountain sickness (AMS) was more frequent among NAM (52.8% vs 35.2%, p < 0.01). EUR sought advice from health care professionals (67.1% vs 52.0%, p < 0.01) and travel medicine practitioners (45.8% vs 37%, p < 0.01) more often. NAM used prophylactic medications more often (53% vs 48.6%, p = 0.00) and received a lower mean number of vaccines (1.97 ± 1.68 vs 2.63 ± 1.49; t-test 14.02, p < 0.01). Advice on safe sex and alcohol consumption was low in both groups, especially among NAM.

CONCLUSIONS

Pre-travel preparation and travel-related illnesses varied between NAM and EUR. Improving consistency of pre-travel preparation based on the best evidence should become a priority among different national bodies providing travel medicine recommendations.

High prevalence of sexually transmitted infections among young Peruvians who have sexual intercourse with foreign travelers in Cuzco

BACKGROUND

Sexual networking in popular tourist destinations is a problem worldwide. In Peru, locals sexually interacting with travelers bridge high-risk groups, the general population, and travelers.

METHODS

A cross-sectional study was conducted in Cuzco about sexual behavior among young Peruvians who admitted having sex with travelers. A subgroup of the participants had serologic testing for Chlamydia trachomatis, Herpes simplex virus (HSV) type 2, and Treponema pallidum.

RESULTS

Eighty-eight subjects volunteered for blood sampling. Their mean age was 22.9 years (+/-4.1) and 53.4% were male. The majority were single (86.2%), but 12.6% had a stable relationship. The median number of sexual partners in the 3 months prior to the study was 2 [interquartile range (IQR): 1-4]. During that period, 43.1% reported foreign partners, 28.4% reported foreign and Peruvian partners, 17% reported Peruvian partners, and the remaining 11.5% reported combinations of Peruvian, foreign, and sex workers partners. The median number of foreign partners in the 12-month period prior to the study was 4 (IQR: 2-8). Only 25.3% reported consistent condom use. Alcohol (69%) and drugs (36.8%) were commonly used before sexual activity. Seventy-eight percent tested positive for HSV type 2, 25% for C trachomatis, and 1.1% for T pallidum.

CONCLUSIONS

The core group of young Peruvians we report on demonstrated a high-risk sexual behavior and a high prevalence of sexually transmitted infections. Our results underscore the need for education on safer sex practices among this group and among travelers.

Frequent HTLV-1 infection in the offspring of Peruvian women with HTLV-1-associated myelopathy/tropical spastic paraparesis or strongyloidiasis

OBJECTIVES

To describe the frequency of HTLV-1 infection among offspring of mothers who had presented with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), strongyloidiasis, or asymptomatic HTLV-1 infection, and to identify factors associated with HTLV-1 infection.

METHODS

In a descriptive study, records were reviewed of HTLV-1-positive women and their offspring who had been tested for HTLV infection at a public hospital in Lima, Peru, from 1989 to 2003. Sons and daughters of women who had presented with strongyloidiasis, HAM/TSP, or asymptomatic infection were eligible for this study.

RESULTS

Three hundred seventy subjects were included: 279 were the offspring of 104 mothers presenting with HAM/TSP, 58 were the offspring of 22 mothers with strongyloidiasis, and 33 were the offspring of 26 asymptomatic mothers. Mean age of the offspring at the time of testing was 26 years (standard deviation 12). Nineteen percent of the offspring tested positive for HTLV-1: 6% (2/33) of those with asymptomatic mothers, 19% (52/279) among the offspring of mothers with HAM/TSP, and 31% (18/58) among the offspring of mothers presenting with strongyloidiasis On multiple logistic regression analysis, three factors were significantly associated with HTLV-1: (a) duration of breast-feeding (odds ratio [OR] = 15.1; [4.2-54.1] for 12 to 24 months versus less than 6 months breast-feeding); (b) clinical condition of the mother (OR = 8.3 [1.0-65.3] for HAM/TSP and OR = 11.5 [1.4-98.4] for strongyloidiasis in comparison with offspring of asymptomatic mothers); and (c) transfusion history (OR = 5.5 [2.0-15.2]).

CONCLUSIONS

In addition to known risk factors for HTLV-1 transmission (duration of breast-feeding and history of blood transfusion), maternal HAM/TSP and strongyloidiasis were associated with seropositivity among offspring of HTLV-1-infected mothers.

Sexual behavior, knowledge of STI prevention, and prevalence of serum markers for STI among tour guides in Cuzco/Peru

BACKGROUND

Sexual behavior during travel has increasingly become a focus of travel medicine research. The perceived freedom when away from home can lead to increased casual sexual activities, often unprotected. Local sexual partners, particularly those who are in close contact with tourists due to their occupation, need to be considered more in research. The purpose of this study was to explore the sexual behavior, knowledge of STI prevention, and prevalence of serum markers of selected STIs in tour guides in Cuzco/Peru.

METHODS

In this cross-sectional study, 161 tour guides completed a questionnaire consisting of information on demographics, sexual behavior, and knowledge about STI prevention. Blood samples of the participants were tested for antibodies against HSV2, Chlamydia trachomatis, and Treponema pallidum using commercial enzyme-linked immunosorbent assay kits.

RESULTS

The majority of guides (65%) were sexually active during the year prior to the study and 10% had foreign partners. Consistent condom use was reported by 38.1%, but almost 42% did not use condoms. In total, 27.6% reported symptoms compatible with STI. Three quarters of the participants had previously received information on STI prevention, predominantly from health professionals. In total, 22% considered themselves at high risk for STI. Antibodies against C trachomatis were prevalent in 15%, while 88.2% were against HSV2. None had antibodies against T pallidum.

CONCLUSIONS

There is an inconsistency in reported sexual behavior and reported knowledge about STI prevention. Because of the tour guides' bridging position between potential STI carriers in tourists and the local population, the reported nonuse of condoms is of concern. The prevalence of serum markers supports this concern, which is aggravated by the potential of noncurable infections. Current sexual health education strategies seem unsatisfactory, and major modifications are highly recommended.

Risk factors associated with diarrhea among international visitors to Cuzco, Peru

The objective of this study was to determine the risk factors for travelers' diarrhea (TD) reported by visitors to Cuzco, Peru. In this cross-sectional study, self-administered questionnaires looking at perceived occurrence of health problems and pre-travel health advice were obtained from departing travelers at Cuzco's International Airport between August and November 2002. A total of 5,988 travelers participated in the study. The mean age was 35 years, and 51% were women. The prevalence of TD was 24%. Factors associated with TD in the multivariable analysis were use of antibiotic prophylaxis (OR: 3.20), vaccination against cholera (OR: 1.44), history of advice for safe food and water consumption (OR: 1.46), being younger than 35 years of age (OR: 1.37), being a resident of the United States (OR: 1.28), not staying in hotels in Cuzco (OR: 1.13), and number of unsafe food or beverages consumed (OR: 1.04). Remaining in Cuzco < 1 week was a protective factor (OR: 0.58). TD is common among travelers to Cuzco. This study suggests that conventional recommendations are not invariably effective at decreasing TD.

Pretravel health advice among international travelers visiting Cuzco, Peru

BACKGROUND

Cuzco, a Peruvian city of historical interest located 3,326 m above sea level, is a frequent destination for tourists. We conducted a descriptive study to assess the extent and sources of pretravel health advice received by international travelers before their arrival to Cuzco.

METHODS

Data were collected as part of a health survey among travelers. Between August and November 2002, travelers between 15 and 65 years old were invited to fill out a questionnaire in the departing area of Cuzco's international airport.

RESULTS

A total of 5,988 travelers participated. The mean age was 35.4 years (SD 11.4 yr); 50.6% were female and 50.8% were single. Tourism was the reason for traveling in 90.2% of the participants, and 89.3% of them were traveling with companions. Pretravel health information was received by 93.6%. The median number of information sources was two, with books (41.5%), travel medicine clinics (38.8%), the Internet (23.3%), and general practitioners (22.7%) as the main sources. Most frequently received recommendations were about safe food and water consumption (85%), use of insect repellents (66.0%), sunburn protection (64.4%), and condom use (22%). Only 16.5% took medication to prevent altitude sickness, and 14.2% took medication to prevent traveler's diarrhea. Variables independently associated with receiving pretravel health information from a health care professional were female gender, country of residence other than the United States, length of stay in Cuzco > 7 days, length of stay in other Peruvian cities > 7 days, tourism as the main reason for visiting Cuzco, traveling with companions, and consulting of more than one source of information.

CONCLUSIONS

Most travelers arriving to Cuzco had received pretravel health information, and the majority obtained it from more than one source. Recommendations addressed for specific health risks, such as altitude sickness prophylaxis, were received by few travelers.

Sexual behavior in travelers visiting Cuzco

BACKGROUND

In South America, little is known about sexual behavior and risk factors for acquiring sexually transmitted diseases (STDs) among travelers and among local people sexually interacting with travelers. There is evidence that, in Peru, significant sexual interaction between these groups exists.

METHOD

An anonymous written questionnaire was administered to travelers in the airport and bus stations before they left Cuzco.

RESULTS

Of the travelers,5.6% engaged in sexual activity with a new partner during their stay in Cuzco. Sexual intercourse with other travelers was most common (76/140, 54.3%), followed by sex with local partners (57/140, 40.7%), and with commercial sex workers (3/140, 2.15%). Consistent condom use was reported by 97/140 (69.3%). In the multivariate analysis, the following variables were independently associated with casual sex: male gender, single marital status, age between 15 and 35 years, non-United States travelers (NUSTs), traveling alone or with friends, length of stay more than 30 days, homosexual or bisexual orientation, and expectation of having sex before traveling. Homosexual and bisexual travelers had 3 or more new sexual partners more frequently than heterosexual travelers (4/8, 18/129, OR=6.17 (1.16<OR<33.5)). NUSTs received more pretravel advice (698/1587, 210/718, OR=1.86 (1.54<OR<2.24)) and engaged in more sexual activity (100/1,587, 25/722, OR=1.86 (1.20<OR<2.93)) than United States travelers (USTs).

CONCLUSION

Travelers visiting Cuzco engage in sexual activities that put them at risk of acquiring STD and transmitting it, both in their home country and in Peru. We recommend the inclusion of Peru and possibly other Latin American countries in the list of destinations where there is substantial risk of transmission of STD and the provision of pretravel advice regarding this issue to travelers to Peru.

Sexual behavior of international travelers visiting Peru

BACKGROUND

Sexual behavior of travelers to Latin America and the sexual behavior of US travelers in general are poorly characterized.

GOAL

The goal of the study was to evaluate sexual risk factors of travelers to Peru.

STUDY DESIGN

Anonymous written questionnaires were administered to 442/507 (87%) of the individuals approached in the international departures area of the Lima airport.

RESULTS

Of the 442 respondents, 54 (12.2%) had new sex partners during their stay. Sex with a local partner (35/52; 67.3%) was more frequent than sex with other travelers (18/52; 34.6%) or with sex workers (4/52; 7.7%). Risk factors for a new sex partner included male sex (relative risk, 1.94), single marital status (relative risk, 2.59), duration of stay longer than 30 days (relative risk, 5.05), traveling alone or with friends (relative risk, 2.88), and bisexual orientation (relative risk, 4.94). Frequency of sexual activity among US travelers was greater than that among travelers from other countries (15.2% [22/145] versus 10.6% [30/282]; NS). Condoms were consistently used by 12/50 (24%) and sometimes used by 10/50 (20%), including 8/20 United States travelers and 13/29 travelers from other countries.

CONCLUSION

Behaviors and risk factors are similar to those described for travelers to Africa, Asia, and Eastern Europe. Behavior of US travelers did not differ from that of other travelers.