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To describe patient characteristics and disease spectrum among foreign visitors to Haiti before and after the 2010 earthquake, we used GeoSentinel Global Surveillance Network data and compared 1 year post-earthquake versus 3 years pre-earthquake. Post-earthquake travelers were younger, predominantly from the United States, more frequently international assistance workers, and more often medically counseled before their trip than pre-earthquake travelers. Work-related stress and upper respiratory tract infections were more frequent post-earthquake; acute diarrhea, dengue, and Plasmodium falciparum malaria were important contributors of morbidity both pre- and post-earthquake. These data highlight the importance of providing destination- and disaster-specific pre-travel counseling and post-travel evaluation and medical management to persons traveling to or returning from a disaster location, and evaluations should include attention to the psychological wellbeing of these travelers. For travel to Haiti, focus should be on mosquito-borne illnesses (dengue and P. falciparum malaria) and travelers' diarrhea.

The objective was to assess the effect on birthweight of antenatal mebendazole plus iron vs. placebo plus iron in a highly hookworm-endemic area. Double-blind randomized controlled trial set in rural and peri-urban communities in the Peruvian Amazon region. A total of 1042 second trimester pregnant women between the ages of 18 and 44 years were recruited from April to November 2003 and followed to July 2004. Women were randomly assigned to receive either mebendazole (500 mg single dose) plus iron supplements (60 mg elemental iron daily) or placebo plus iron supplements. The primary outcome was mean infant birthweight and secondary measures included proportion of low birthweight babies and maternal anaemia. The prevalence of hookworm infection was 47.5%. There were no differences between intervention groups in mean birthweight (3104 g vs. 3090 g P = 0.629) proportion of low birthweight (< 2500 g; 8.1% vs. 8.7% P = 0.755) or maternal anaemia in the third trimester [33.0% (158/479) vs. 32.3% (152/471) P = 0.815]. However the proportion of very low birthweight (< 1500 g) was significantly lower in the mebendazole group [0% (0/479) vs. 1.5% (7/471) P = 0.007]. This trial provides additional evidence for the use of anthelmintics over and above iron supplementation within antenatal care programmes in hookworm-endemic areas. Benefits of de-worming may be higher in countries not having an antenatal iron supplementation programme or where intensity of hookworm infections is higher. (authors)

Albendazole is a benzimidazole with wide spectrum coverage as an antiparasitic drug. Reported side effects have been minimal. We report the case of a patient who died with severe prolonged pancytopenia beginning during the third week of therapy for a pulmonary echinococcal cyst. This case was a 68-year-old man who presented with a large cystic lung mass. His medical history was significant for Child-Pugh class B cirrhosis. A prolonged course of albendazole was initiated. Two weeks later, the patient presented in septic shock with severe pancytopenia. The patient was initially resuscitated, but died after 10 days with no marrow recovery. Autopsy was consistent with albendazole-induced pancytopenia. This is the third human case of pancytopenia and the first death reported in relation to albendazole-induced pancytopenia. Neutropenia seems to be related more to higher dosage and longer duration of use. Albendazole sulfoxide peak dose and half life are significantly prolonged by liver disease and concomitant administration of certain drugs. The severity and duration of albendazole-induced pancytopenia in this case was likely related to the underlying liver disease. Frequent serial monitoring of blood counts and cessation of medication with any evidence of marrow toxicity in such patients is warranted.

Background: Imported malaria is an increasing problem. The arrival of 224 African refugees presented the opportunity to investigate the diagnosis and management of imported malaria within the Quebec health care system. Methods: The refugees were visited at home 3–4 months after arrival in Quebec. For 221, a questionnaire was completed and permission obtained for access to health records; a blood sample for malaria testing was obtained from 210. Results: Most of the 221 refugees (161 [73%]) had had at least 1 episode of malaria while in the refugee camps. Since arrival in Canada, 87 (39%) had had symptoms compatible with malaria for which medical care was sought. Complete or partial records were obtained for 66 of these refugees and for 2 asymptomatic adults whose children were found to have malaria: malaria had been appropriately investigated in 55 (81%); no malaria smear was requested for the other 13. Smears were reported as positive for 20 but confirmed for only 15 of the 55; appropriate therapy was verified for 10 of the 15. Of the 5 patients with a false-positive diagnosis of malaria, at least 3 received unnecessary therapy. Polymerase chain reaction testing of the blood sample obtained at the home visit revealed malaria parasites in 48 of the 210 refugees (23%; 95% confidence interval [CI] 17%– 29%). The rate of parasite detection was more than twice as high among the 19 refugees whose smears were reported as negative but not sent for confirmation (47%; 95% CI 25%– 71%). Interpretation: This study has demonstrated errors of both omission and commission in the response to refugees presenting with possible malaria. Smears were not consistently requested for patients whose presenting complaints were not “typical” of malaria, and a large proportion of smears read locally as “negative” were not sent for confirmation. Further effort is required to ensure optimal malaria diagnosis and care in such high-risk populations.

The importation of malaria into a region where it is not endemic raises many concerns, including the timely delivery of appropriate care, safety of the blood supply, and the risk of autochthonous transmission. There is presently no consensus on the best way to screen mobile populations for malaria. Between August 2000 and March 2001, 535 refugees arrived in Quebec, Canada, from Tanzanian camps. Within 4 weeks of resettlement of the first group of 224, the McGill University Centre for Tropical Diseases noted an outbreak of malaria across the province (15 cases over a 3-week period). This group (group 1) was traced and screened for malaria between 3 and 4 months after arrival in Canada. Subsequent groups of 106 and 205 refugees were screened immediately upon arrival in Canada (group 2) and immediately prior to their departure from refugee camps (group 3), respectively. A single EDTA-blood sample was obtained from 521 refugees for testing by thick and thin blood smears (groups 1 and 2), antigen detection (ICT Malaria Pf and OptiMAL; group 1 only), and nested PCR (all groups). Overall, 98 of 521 refugees were found to be infected (18.8%). The vast majority of infections (81 of 98) were caused by Plasmodium falciparum alone. Using PCR as the “gold standard,” both microscopy (sensitivity, 50%; specificity, 100%) and antigen detection (ICT sensitivity, 37.5%; ICT specificity, 100%; OptiMAL sensitivity, 29.1%; OptiMAL specificity, 95.6%) performed poorly. None of the PCR-positive subjects were symptomatic at the time of testing, and only two had recently had symptoms compatible with malaria (with or without diagnosis and treatment). Active surveillance of migrants from regions of intense malaria transmission can reduce the risk of morbidity in the migrant population and mitigate against transmission to the host population. Our data demonstrate that PCR is, by far, the most powerful tool for such surveillance.

Repeated outbreaks of trichinellosis caused by the consumption of Trichinella-infected walrus (Odobenus rosmarus) meat, which have sometimes led to serious morbidity, have stimulated Inuit communities in Nunavik (northern Quebec), Canada, to develop an innovative trichinellosis prevention program. The program involves preconsumption testing of meat samples from harvested walrus at a regional laboratory and the rapid dissemination of the results of such testing to communities. Local health authorities in Inukjuak conducted an epidemiological investigation after testing identified Trichinella-positive walrus meat in September 1997. This report describes the events that occurred before, during, and after the trichinellosis outbreak and also documents how the prevention program contributed to successful resolution of the outbreak.

Presentation of Case A 50-year-old man was admitted to the Tropical and Geographic Medicine Center of this hospital because of eosinophilia and fluctuating hepatic lesions. The patient had been well until 10 months earlier, when he was splashed in the face while brushing his dog's teeth. He subsequently noted a sore on the left side of his nose, which progressed to a frank abscess. The abscess resolved with the administration of cephalexin, but diffuse myalgias, sweats, and headache soon developed, accompanied by fever (temperature, up to 40°C) and a rash on the legs that progressed to the trunk. The rash . . .

This chapter provides a descripition of an outbreak of a new clinical disease, acute metorchiasis. Metorchis conjunctus is a fluke belonging to the family Opisthorchidae, in which human infections with the closely related O. viverrini, O. felineus and Clonorchis sinensis have been extensively investigated. Like other flukes in this family, it lives within the biliary tree of the definitive host. The first intermediate host of M. conjunctus is the aquatic snail Amnicola limosa limosa. The second intermediate hosts include several freshwater fish species; the most important is the white sucker. Asymptomatic human infection with M. conjunctus has been seen occasionally during stool parasite surveys in aboriginal populations in Canada. The morbidity associated with fish parasites varies from asymptomatic to serious and is based on the parasite itself, the parasite load, and host response. The fish tapeworms Diphyllobothrium spp. (of which there are three and possibly more species described in North America) are the most frequently described human helminths of fish origin on the continent. The present outbreak and the prevalence of the fluke M. conjunctus place this parasite among the more common fish-borne helminths that infect humans in North America.

Human gnathostomiasis is a nonpatent zoonotic infection caused by tissue migration of Gnatho­ stoma splmgerum larvae. Most human infections reported in the literature are caused by this species; several other Gnathostoma species infect animals. G. spinigerum is an intestinal nematode of carnivores. Humans contract the infection by eating raw or under­ cooked dishes prepared from infected second interme­ diate hosts (e.g., fish, chicken, pig, frog or snake meat).! These hosts acquire the infection by ingesting freshwater cyclops containing the infective-stage lar­ vae. 2 Cats and dogs in Thailand are considered to be important reservoirs for spreading gnathostomiasis to humans.2 Cutaneous gnathostomiasis, the clinical form most commonly reported in humans, is characterized by migratory swelling resembling subcutaneous larva migrans or cellulitis. Occasionally, deeper tissues, such as the eyes, lungs, abdomen or brain, may be involved by the migrating larvae) We report a case of intraocular gnathostomiasis in a female immigrant from Bangladesh. To our knowl­ edge, this is the first case of intraocular gnathostomia­ sis reported in Canada. CASE REPORT

We report 2 clinically characteristic and serologically positive cases of Ross River virus infection in Canadian tourists who visited Fiji in late 2003 and early 2004. This report suggests that Ross River virus is once again circulating in Fiji, where it apparently disappeared after causing an epidemic in 1979 to 1980.

A follow-up prevalence study was done in 1989 of the same Kampuchean refugee population (247 subjects) that had been screened and treated for intestinal parasite infection 6 years earlier. A control group (102 subjects) included Kampuchean refugees who had arrived in Montreal at about the same time. These groups did not differ in age, sex, family size, or number of months spent in refugee camps. Statistically significant prevalence differences were observed in the rescreened group between 1982-1983 (63.7%) and 1989 (21.9%) and between the rescreened group and the control group (39.2%). These differences are largely attributable to the elimination of Ascaris infection and decreases in Giardia and hookworm infections. However, Strongyloides infection decreased only slightly (from 15% to 11%) in the rescreened group, while 12% of the control group was infected. Despite an early screening and treatment program, there remain important health risks in this immigrant population due to long-lived potentially pathogenic parasites.

As part of a screening and treatment program for intestinal parasite infections offered to newly arrived Southeast Asian refugees in Canada between July 1982 and February 1983, a total of 232 sera were tested for Strongyloides infection using an enzyme-linked immunosorbent assay (immunoglobulin G). These results were compared with coprologic results and eosinophil counts. The seroprevalence was 76.6% (131 of 171) among Kampucheans, 55.6% (15 of 27) among Laotians, and 11.8% (4 of 34) among Vietnamese. A statistically significant relation (p less than 0.001) was found between Strongyloides serology and Strongyloides infection on stool examination (prevalence, 24.7%) among Kampucheans. Eosinophilia (greater than or equal to 10%) was found to be significantly associated with both infection measures. Using coprologic results as the "gold standard," the properties of the serologic test were estimated to be: sensitivity (95%), specificity (29%), positive predictive value (30%), and negative predictive value (95%). These estimates should be regarded as minimal values, as stool examination for Strongyloides infection can be an unreliable diagnostic reference. Further evaluation of the discrepancies observed between coprologic and serologic testing is required to determine the usefulness of these tests in epidemiologic studies.

We report the case of a 23-year-old Caribbean man with disseminated strongyloidiasis (co-infected with human T cell lymphotropic virus I/II)), severe hypoalbuminemia, and a paralytic ileus. Subcutaneous ivermectin (200 microg/kg) was administered daily for 14 days because of the inability to effectively administer oral albendazole and oral ivermectin. Three hours after the third daily dose of oral ivermectin, the serum ivermectin concentration was only 0.8 ng/mL, but it increased several fold to 5.8 ng/mL 16 hours after the first dose of subcutaneous ivermectin. During the course of subcutaneous treatment, ivermectin clearance was higher than expected (46.0 L/hour, normal = 31.8 L/hour). This is likely the result of severe hypoalbuminemia since ivermectin is highly protein bound. The ability to achieve adequate levels of ivermectin after oral administration in patients with disseminated strongyloidiasis may be impaired, highlighting the need for alternative routes of administration of ivermectin in these patients.

Albendazole is a benzimidazole with wide spectrum coverage as an antiparasitic drug. Reported side effects have been minimal. We report the case of a patient who died with severe prolonged pancytopenia beginning during the third week of therapy for a pulmonary echinococcal cyst. This case was a 68-year-old man who presented with a large cystic lung mass. His medical history was significant for Child-Pugh class B cirrhosis. A prolonged course of albendazole was initiated. Two weeks later, the patient presented in septic shock with severe pancytopenia. The patient was initially resuscitated, but died after 10 days with no marrow recovery. Autopsy was consistent with albendazole-induced pancytopenia. This is the third human case of pancytopenia and the first death reported in relation to albendazole-induced pancytopenia. Neutropenia seems to be related more to higher dosage and longer duration of use. Albendazole sulfoxide peak dose and half life are significantly prolonged by liver disease and concomitant administration of certain drugs. The severity and duration of albendazole-induced pancytopenia in this case was likely related to the underlying liver disease. Frequent serial monitoring of blood counts and cessation of medication with any evidence of marrow toxicity in such patients is warranted.

Malaria surveillance data are evaluated for causes of epidemics in Canada., In the past decade, fluctuations in numbers of imported malaria cases have been seen in Canada. In 1997 to 1998, malaria case numbers more than doubled before returning to normal. This increase was not seen in any other industrialized country. The Canadian federal malaria surveillance system collects insufficient data to interpret these fluctuations. Using local (sentinel), provincial, federal, and international malaria surveillance data, we evaluate and interpret these fluctuations. Several epidemics are described. With an ever-increasing immigrant and refugee population of tropical origin, improved surveillance will be necessary to guide public health prevention policy and practice. The Canadian experience is likely to be generalizable to other industrialized countries where malaria is a reportable disease within a passive surveillance system.

Background Increases in travel‐related illness require new partnerships to ensure travelers are prepared for health risks abroad. The travel agent is one such partner and efforts to encourage travel agents to refer at‐risk travelers to travel health clinics may help in reducing travel‐attributable morbidity. Methods A health promotion intervention encouraging travel agents to refer at‐risk travelers to travel health clinics was evaluated. Information on the knowledge, attitudes, and behaviors of travel agents before and after the intervention was compared using two self‐administered questionnaires. The Wilcoxon signed rank test was used to compare the mean difference in overall scores to evaluate the overall impact of the intervention and also subscores for each of the behavioral construct groupings (attitudes, barriers, intent, and subjective norms). Multiple regression techniques were used to evaluate which travel agent characteristics were independently associated with a stronger effect of the intervention. Results A small improvement in travel agents’ overall attitudes and beliefs (p = .03) was found, in particular their intention to refer (p = .01). Sixty‐five percent of travel agents self‐reported an increase in referral behavior; owners or managers of the agency were significantly more likely to do so than other travel agents (OR = 7.25; 95% CI: 1.64–32.06). Older travel agents, those that worked longer hours and those with some past referral experience, had significantly higher post‐intervention scores. Conclusion Travel agents can be willing partners in referral, and agencies should be encouraged to develop specific referral policies. Future research may be directed toward investigating the role of health education in certification curricula, the effectiveness of different types of health promotion interventions, including Internet‐facilitated interventions, and the direct impact that such interventions would have on travelers attending travel health clinics.

Posttravel screening is the clinical and laboratory assessment of an individual aimed at uncovering occult infections, pathology, or health risks, the treatment of which will yield a significant health benefit to the individual. Screening must be tailored to the different risk patterns associated with different travel categories (e.g., missionary, tourist). Screening, predominantly a secondary prevention strategy, is most cost-effective when integrated with primary prevention strategies aimed at preventing future travel related illness (Table 6). The screening process begins with a medical history that allows a definition of risks and a tailored approach to laboratory tests. The screening tests currently available for STDs, tuberculosis, and parasitic infections have been reviewed, and although cost-effectiveness data are not available for most post-travel screening tests, recommended approaches are proposed. Traditionally, screening has been directed at uncovering occult infectious disease (STDs, tuberculosis, and parasitic infections). Important benefits can be gained, however, by including screening questions and tests for those diseases that are the major causes of mortality, both in nontraveling and in traveling North Americans, that is, the atherosclerotic and neoplastic diseases and trauma, especially vehicular.

These results document the presence of potentially pathogenic zoonotic helminth parasites in the day-care environment. Evidence from the literature regarding the health risk to children is insufficient and highlights the need for further research assessing the risk of human infection and subsequent morbidity, the viability of these parasites under different environmental conditions, and practical issues related to the management of sand and soil.

A randomized, controlled trial was undertaken to evaluate the effects of a screening program for intestinal parasite infection in newly arrived Southeast Asian refugees to Montréal, Québec, Canada, during 1982-1983. Families assigned to the screened groups were examined, infected persons were treated and followed until they were infection-free, and all screened families were reexamined at six months. Families assigned to the control groups were examined at six months only. Statistically significant prevalence differences in unadjusted and adjusted estimates over the six-month study period were found between screened persons and controls for each of three groups of refugees from Kampuchea, Laos, and Vietnam, respectively. In general, the greatest prevalence differences ascribed to the screening program were observed in hookworm and Ascaris lumbricoides infections. Continued high levels of Giardia lamblia and Strongyloides stercoralis infection were observed at six months; this raises concerns over the effective therapeutic management of infected persons, the risk of local transmission, and the relevance of screening for intestinal parasites in new arrivals from endemic areas.

We describe an outbreak of trichinosis after the consumption of raw walrus meat in 10 Inuit inhabitants of a northern community. During the presentation of the illness, diarrhea was found in all subjects and was the dominant symptom in 8 of the 10 cases. Myalgia (60%) and muscle weakness (50%) were much less prominent complaints. The diarrhea was characteristically prolonged, lasting up to 14 wk (average 5.8 wk), as opposed to comparatively short episodes of myalgia (average 5.4 days) and muscle weakness (average 4.5 days). Prolonged diarrhea with little or no muscle symptomatology in an epidemic form represents a previously unrecognized clinical presentation of trichinosis. It remains to be determined whether this new clinical presentation is related to variant biological behavior of arctic Trichinella, to previous exposure to the parasite, or to other factors.