Infections with long latency in international refugees, immigrants, and migrants seen at GeoSentinel sites, 2016-2018.

BACKGROUND: The continued increase in global migration compels clinicians to be aware of specific health problems faced by refugees, immigrants, and migrants (RIM). This analysis aimed to characterize RIM evaluated at GeoSentinel sites, their migration history, and infectious diseases detected through screening and diagnostic workups. METHODS: A case report form was used to collect data on demographics, migration route, infectious diseases screened, test results, and primary infectious disease diagnosis for RIM patients seen at GeoSentinel sites. Descriptive statistics were performed. RESULTS: Between October 2016 and November 2018, 5,319 RIM patients were evaluated at GeoSentinel sites in 19 countries. Africa was the region of birth for 2,436 patients (46 %), followed by the Americas (1,644, 31 %), and Asia (1,098, 21 %). Tuberculosis (TB) was the most common infection screened and reported as positive (853/2,273, 38 % positive by any method). TB, strongyloidiasis, and hepatitis B surface antigen positivity were observed across all migration administrative categories and regions of birth. Chagas disease was reported only among RIM patients from the Americas (393/394, 100 %) and schistosomiasis predominantly in those from Africa (480/510, 94 %). TB infection (694/5,319, 13 %) and Chagas disease (524/5,319, 10 %) were the leading primary infectious disease diagnoses. CONCLUSIONS: Several infections of long latency (e.g. TB, hepatitis B, and strongyloidiasis) with potential for long-term sequelae were seen among RIM patients across all migration administrative categories and regions of origin. Obtaining detailed epidemiologic information from RIM patients is critical to optimize detection of diseases of individual and public health importance, particularly those with long latency periods.

Comparing the Use of a Mobile App and a Web-Based Notification Platform for Surveillance of Adverse Events Following Influenza Immunization: Randomized Controlled Trial.

BACKGROUND: Vaccine safety surveillance is a core component of vaccine pharmacovigilance. In Canada, active, participant-centered vaccine surveillance is available for influenza vaccines and has been used for COVID-19 vaccines. OBJECTIVE: The objective of this study is to evaluate the effectiveness and feasibility of using a mobile app for reporting participant-centered seasonal influenza adverse events following immunization (AEFIs) compared to a web-based notification system. METHODS: Participants were randomized to influenza vaccine safety reporting via a mobile app or a web-based notification platform. All participants were invited to complete a user experience survey. RESULTS: Among the 2408 randomized participants, 1319 (54%) completed their safety survey 1 week after vaccination, with a higher completion rate among the web-based notification platform users (767/1196, 64%) than among mobile app users (552/1212, 45%; P<.001). Ease-of-use ratings were high for the web-based notification platform users (99% strongly agree or agree) and 88.8% of them strongly agreed or agreed that the system made reporting AEFIs easier. Web-based notification platform users supported the statement that a web-based notification-only approach would make it easier for public health professionals to detect vaccine safety signals (91.4%, agreed or strongly agreed). CONCLUSIONS: Participants in this study were significantly more likely to respond to a web-based safety survey rather than within a mobile app. These results suggest that mobile apps present an additional barrier for use compared to the web-based notification-only approach. TRIAL REGISTRATION: ClinicalTrials.gov NCT05794113; https://clinicaltrials.gov/show/NCT05794113.

Post-Artesunate Delayed Hemolysis: A Review of Current Evidence.

Artesunate is the drug of choice for treating patients with severe malaria. Post-artesunate delayed hemolysis (PADH) is an uncommon adverse event from malaria treatment. Most patients with PADH are non-immune travelers. The pathophysiology of PADH is not fully understood, but the most likely mechanism is "pitting", in which red blood cells carrying dead parasites killed by artesunate's action are directed to the spleen for clearing the dead parasites. After the cleansing process, these red blood cells re-enter the circulation but with a smaller size and impaired integrity, resulting in a shortened lifespan of 7-21 days. Therefore, most patients with PADH usually present with clinical features of hemolytic anemia 7 days or later after the initiation of artesunate. To date, the benefits of artesunate treatment outweigh its adverse events, and no fatal cases have resulted from PADH. However, the hematological follow-up of patients with malaria treated with artesunate is recommended for clinicians to detect any delayed hemolytic event early and prevent potentially serious consequences.

Recalibrated estimates of non-bacteremic and bacteremic pneumococcal community acquired pneumonia in hospitalized Canadian adults from 2010 to 2017 with addition of an extended spectrum serotype-specific urine antigen detection assay.

OBJECTIVE(S): In the context of age- and risk-based pneumococcal vaccine recommendations in Canada, this study presents updated data from active surveillance of pneumococcal community acquired pneumonia (pCAP) and invasive pneumococcal disease (IPD) in hospitalized adults from 2010 to 2017. METHODS: S. pneumoniae was detected using culture (blood and sputum), and urine antigen detection (UAD). Serotyping was performed with Quellung, PCR, or using the PCV13- and PPV23 (non-PCV13)-specific UADs. Laboratory results, demographic, and outcome data were categorized by age (16-49, 50-64, and 65 + ) and by disease [non-bacteremic pCAP, bacteremic pCAP, and IPD(non-CAP)]. RESULTS: 11,129 CAP cases and 216 cases of IPD (non-CAP) were identified. Laboratory testing for S. pneumoniae was performed in 8912 CAP cases, identifying 1264 (14.2%) as pCAP. Of pCAP cases, 811 (64.1%) were non-bacteremic and 455 (35.9%) were bacteremic. Adults 65 + years represented 54.5% of non-bacteremic pCAP, 41.4% of bacteremic pCAP, and 48.6% of IPD cases. Adults 50-64 years contributed 30.3%, 33.1%, and 29.9%, respectively. In pCAP, PCV13 serotypes declined between 2010 and 2014 due to declines in serotypes 7F and 19A, then plateaued from 2015 to 2017 with persistence of serotype 3. In later study years, non-bacteremic pCAP was predominant, and PPV23 (non-PCV13) serotypes increased from 2015 to 2017, with serotypes 22F, 11A, and 9 N being most frequently identified. Compared to non-pCAP, pCAP cases were more likely to be admitted to intensive care units and require mechanical ventilation. These outcomes and mortality were more common in bacteremic pCAP and IPD, versus non-bacteremic pCAP. CONCLUSION(S): Along with IPD, pCAP surveillance (bacteremic and non-bacteremic) is important as their trends may differ over time. With insufficient herd protection from PCV13 childhood immunization, or use of PPV23 in adults, this study supports direct adult immunization with PCV13 or higher valency conjugate vaccines to reduce the residual burden of pCAP and IPD.

2017/18 and 2018/19 seasonal influenza vaccine safety surveillance, Canadian National Vaccine Safety (CANVAS) Network.

BackgroundThe Canadian National Vaccine Safety (CANVAS) network monitors the safety of seasonal influenza vaccines in Canada.AimTo provide enhanced surveillance for seasonal influenza and pandemic influenza vaccines.MethodsIn 2017/18 and 2018/19 influenza seasons, adults (≥ 15 years of age) and parents of children vaccinated with the seasonal influenza vaccine participated in an observational study using web-based active surveillance. Participants completed an online survey for health events occurring in the first 7 days after vaccination. Participants who received the influenza vaccine in the previous season, but had not yet been vaccinated for the current season, were unvaccinated controls.ResultsIn 2017/18, 43,751 participants and in 2018/19, 47,798 completed the online safety survey. In total, 957 of 30,173 participants vaccinated in 2017/18 (3.2%; 95% confidence interval (CI): 3.0-3.4) and 857 of 25,799 participants vaccinated in 2018/19 (3.3%; 95% CI: 3.1-3.5) reported a health problem of sufficient intensity to prevent their normal daily activities and/or cause them to seek medical care (including hospitalisation). This compared to 323 of 13,578 (2.4%; 95% CI: 2.1-2.6) and 544 of 21,999 (2.5%; 95% CI: 2.3-2.7) controls in each respective season. The event rate in vaccinated adults and children was higher than the background rate and was associated with specific influenza vaccines. The higher rate of events was associated with systemic symptoms and migraines/headaches.ConclusionIn 2017/18 and 2018/19, higher rates of events were reported following seasonal influenza vaccination than in the pre-vaccination period. This signal was associated with several seasonal influenza vaccine products.

Zika among international travellers presenting to GeoSentinel sites, 2012-2019: implications for clinical practice.

INTRODUCTION: International travellers contribute to the rapid spread of Zika virus (ZIKV) and its sentinel identification globally. We describe ZIKV infections among international travellers seen at GeoSentinel sites with a focus on ZIKV acquired in the Americas and the Caribbean, describe countries of exposure and traveller characteristics, and assess ZIKV diagnostic testing by site. METHODS: Records with an international travel-related diagnosis of confirmed or probable ZIKV from January 2012 through December 2019 reported to GeoSentinel with a recorded illness onset date were included to show reported cases over time. Records from March 2016 through December 2019 with an exposure region of the Americas or the Caribbean were included in the descriptive analysis. A survey was conducted to assess the availability, accessibility and utilization of ZIKV diagnostic tests at GeoSentinel sites. RESULTS: GeoSentinel sites reported 525 ZIKV cases from 2012 through 2019. Between 2012 and 2014, eight cases were reported, and all were acquired in Asia or Oceania. After 2014, most cases were acquired in the Americas or the Caribbean, a large decline in ZIKV cases occurred in 2018-19.Between March 2016 and December 2019, 423 patients acquired ZIKV in the Americas or the Caribbean, peak reporting to these regions occurred in 2016 [330 cases (78%)]. The median age was 36 years (range: 3-92); 63% were female. The most frequent region of exposure was the Caribbean (60%). Thirteen travellers were pregnant during or after travel; one had a sexually acquired ZIKV infection. There was one case of fetal anomaly and two travellers with Guillain-Barré syndrome. GeoSentinel sites reported various challenges to diagnose ZIKV effectively. CONCLUSION: ZIKV should remain a consideration for travellers returning from areas with risk of ZIKV transmission. Travellers should discuss their travel plans with their healthcare providers to ensure ZIKV prevention measures are taken.

Investigating the association of receipt of seasonal influenza vaccine with occurrence of anesthesia/paresthesia and severe headaches, Canada 2012/13-2016/17, the Canadian Vaccine Safety Network.

BACKGROUND: Concern about adverse events following immunization is frequently cited by both those who receive or decline vaccines. Neurological adverse events are especially concerning. OBJECTIVES: Our aim was to detect associations between seasonal influenza vaccination and the occurrence of severe anesthesia/paresthesia or severe headaches. METHODS: Data were analyzed from the Canadian National Vaccine Safety network. Events occuring on days 0-7 were self-reported and prevented daily activity, led to school or work absenteeism, or required medical attention. Controls were the previous year's vaccinees; events in controls were collected prior to the start of the influenza vaccination program of each year (2012/13 through 2016/17). Multivariable logistic regression was used to determine the association between seasonal influenza vaccination and the occurrence of anesthesia/paresthesia or severe headaches. RESULTS: The total sample was 107,565 for investigating anesthesia/paresthesia and 97,420 for investigating severe headaches. Anesthesia/paresthesia was reported by 104/107,565 (0.10%) participants; 63/69,129 (0.09%) vaccinees and 41/38,436 (0.11%) controls (adjusted odds ratio (aOR) = 0.89; 95% CI = 0.60, 1.32). Severe headaches were reported by 1361/97,420 (1.40%) participants; 907/61,463 (1.48%) vaccinees and 454/35,957 (1.26%) controls (aOR = 1.21; 95% CI = 1.08, 1.36). No specific vaccine product was associated with severe headaches. CONCLUSIONS: Our study found no association between severe anesthesia/paresthesia and seasonal influenza vaccination. While there was an association with severe headaches as an adverse event following influenza vaccination, the rates of these events are similar to rates reported from clinical trials and are not a cause for additional concern.

Physical therapy interventions for cervicogenic dizziness in a military-aged population: protocol for a systematic review.

BACKGROUND: Traumatic cervicogenic dizziness is dizziness that is temporally associated with neck pain and injury after other causes of dizziness have been excluded. It can lead to activity limitations and participation restrictions that may include lost duty or work days. The objective of this systematic review is to determine which interventions are most effective in decreasing dizziness or vertigo and neck pain in military-aged adults with traumatic cervicogenic dizziness. METHODS: The literature will be systematically searched using the following online databases: MEDLINE, EMBASE, The Cochrane Library (Cochrane Database of Systematic Reviews, CENTRAL, Cochrane Methodology Register), CINAHL, SCOPUS, Web of Science, and J-STAGE. The review will include randomized controlled trials (RCTs), including cluster RCTs and controlled (non-randomized) clinical trials or cluster trials, and observational studies (including prospective and retrospective comparative cohort and case-control or nested case-control studies) and determine the effectiveness of physical therapy interventions for the treatment of traumatic cervicogenic dizziness in military-aged adults. Assessment of methodological quality will be performed by two independent, blinded reviewers using the PEDro scale. The level of evidence will be determined using the GRADE scale. The primary outcome measures will be change in dizziness and neck pain and disability from baseline to the last available follow-up, measured using the Dizziness Handicap Inventory and Neck Disability Index. Other relevant outcome measures will include self-reported change in symptoms, time to return to duty or work, and quality of life. DISCUSSION: This systematic review will identify, evaluate, and integrate the evidence on the effectiveness of physical therapy interventions for cervicogenic dizziness in a military-aged population. We anticipate our findings may inform individual treatment and future research. Clinical recommendations generated from this systematic review may inform military physical therapy treatment of individuals with cervicogenic dizziness. SYSTEMATIC REVIEW REGISTRATION: In accordance with the guidelines, our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 21 January 2020 (registration number CRD42020150853). In the event of protocol amendments, the date of each amendment will be accompanied by a description of the change and the rationale.

A Qualitative Study of Preparation for Lumbar Spinal Stenosis Surgery: Perceptions of Patients and Physical Therapists.

OBJECTIVES: To gain the perspectives of patients who underwent lumbar spinal stenosis (LSS) surgery and physical therapists who treat spine-related disorders regarding rehabilitation and other care prior to LSS surgery. DESIGN: Qualitative focus group study. METHODS: Sixteen patients (4 female; average ± SD age, 64.3 ± 8.8 years; time since surgery, 9.9 ± 4.4 months) and 10 physical therapists (2 female; average ± SD age, 40.9 ± 6.6 years; time in practice, 17.2 ± 7.7 years) participated. Four groups were conducted: 2 with patients post LSS surgery and 2 with physical therapists who treat spine-related disorders. Participants were asked open-ended questions by a trained facilitator regarding their perceptions of preoperative LSS education and rehabilitation. Transcripts were coded and themes were identified. RESULTS: Analyses revealed 4 themes within the discussions: (1) desire for helpful information, (2) benefits of preoperative rehabilitation, (3) downfalls of preoperative rehabilitation, and (4) desire for coordinated care. Varying opinions on preoperative physical therapy between patients and physical therapists were discussed, revealing that similar numbers of participants held positive and negative perceptions of preoperative physical therapy. A desire for more thorough preoperative education and care was expressed by both groups. CONCLUSION: There is a clear need for standardized preoperative LSS care and education. This may decrease misunderstandings about LSS surgery and its treatments in the future as well as improve coordinated care between surgeons and physical therapists. J Orthop Sports Phys Ther 2020;50(4):198-205. Epub 30 Oct 2019. doi:10.2519/jospt.2020.8887.

Streptococcus pneumoniae serotype 3 is masking PCV13-mediated herd immunity in Canadian adults hospitalized with community acquired pneumonia: A study from the Serious Outcomes Surveillance (SOS) Network of the Canadian immunization research Network (CIRN).

BACKGROUND: The 13-valent pneumococcal conjugate vaccine (PCV13) was recently shown to be effective against PCV13-type invasive pneumococcal disease (IPD) and pneumococcal community acquired pneumonia (CAPSpn) in healthy adults aged ≥65 years, prompting many countries to re-assess adult immunization. In Canada, the potential benefits of adult PCV13 immunization were unclear given anticipated herd immunity from PCV13 childhood immunization introduced since 2010. This study describes the serotype distribution and clinical outcomes of Canadian adults aged ≥16 years, who were hospitalized with CAPSpn and IPD from 2010 to 2015. METHODS: Active surveillance for CAP and IPD was performed in adult hospitals across five Canadian provinces. IPD was identified when Streptococcus pneumoniae was isolated from sterile sites. Bacteremic and non-bacteremic CAPSpn were identified using blood culture, and sputum culture or PCV13-specific urine antigen detection (UADPCV13), respectively. Serotype was assigned using Quellung reaction, PCR, or UADPCV13. RESULTS: Of 6687 CAP cases where a test was performed, S. pneumoniae positivity decreased from 15.9% in 2011 to 8.8% in 2014, but increased to 12.9% in 2015. CAPSpn attributed to PCV13 serotypes followed a similar trend, dropping from 8.3% in 2010 to 4.6% in 2014, but increasing to 6.3% in 2015. The decline was primarily attributed to serotypes 7F and 19A, and the proportional increase to serotype 3. Similar trends were noted for bacteremic and non-bacteremic CAPSpn. Serious outcomes such as 30-day mortality, intensive care unit admission, and requirement for mechanical ventilation were prominent in CAPSpn and IPD cases, but remained unchanged over the study years. CONCLUSION: Herd immunity afforded primarily by serotypes 7F and 19A appears to be partly masked by a concomitant proportional increase of serotype 3. Despite evidence of herd immunity, these PCV13 serotypes remain persistent in Canadian adults hospitalized with CAPSpn, and represent between 5 and 10% of all CAP in this patient population.

Spectrum of illness in migrants to Canada: sentinel surveillance through CanTravNet.

BACKGROUND: Due to ongoing political instability and conflict in many parts of the world, migrants are increasingly seeking asylum and refuge in Canada. METHODS: We examined demographic and travel correlates of illnesses among migrants to Canada to establish a detailed epidemiologic framework of this population for Canadian practitioners. Data on ill-returned Canadian travellers presenting to a CanTravNet site between 1 January 2015 and 31 December 2015 were analyzed. RESULTS: During the study period, 2415 ill travellers and migrants presented to a CanTravNet site, and of those, 519 (21.5%) travelled for the purpose of migration. Sub-Saharan Africa (n = 160, 30.8%), southeast Asia (n = 84, 16.2%) and south central Asia (n = 75, 14.5%) were the most common source regions for migrants, while the top specific source countries, of 98 represented, were the Philippines (n = 45, 8.7%), China (n = 36, 6.9%) and Vietnam (n = 31, 6.0%). Compared with non-migrant travellers, migrants were more likely to have a pre-existing immunocompromising medical condition, such as HIV or diabetes mellitus (P < 0.0001), and to require inpatient management of their illness (P < 0.0001). Diagnoses such as tuberculosis (n = 263, 50.7%), hepatitis B and C (n = 78, 15%) and HIV (n = 11, 2.1%) were over-represented in the migrant population compared with non-migrant travellers (P < 0.0001). Most cases of tuberculosis in the migrant population (n = 263) were latent (82% [n = 216]); only 18% (n = 47) were active. CONCLUSIONS: Compared with non-migrant travellers, migrants were more likely to present with a communicable infectious disease, such as tuberculosis, potentially complicated by an underlying immunosuppressing condition such as HIV. These differences highlight the divergent healthcare needs in the migrant population, and underscore the importance of surveillance programmes to understand their burden of illness. Intake programming should be adequately resourced to accommodate the medical needs of this vulnerable population of new Canadians.

The changing landscape of travel health services in Canada.

Canadians are increasingly travelling to areas that would necessitate a pre-travel consultation. Changes in professional regulations in Canada allow greater autonomy of nurses and pharmacists, resulting in shifts in provision of travel health services. We surveyed 824 Canadian travel clinics, 270 (33%) of whom responded. Private clinics were most common, and more likely to offer extended hours and drop-in appointments. In one province, pharmacies dominated. Half the services were relatively new and a similar proportion saw fewer than 10 patients weekly; 1/3 had a single provider. The increased spectrum of services may increase convenience for travellers but the large proportion seeing low numbers of clients will challenge providers to maintain competence.

Zika beyond the Americas: Travelers as sentinels of Zika virus transmission. A GeoSentinel analysis, 2012 to 2016.

BACKGROUND: Zika virus (ZIKV) was first isolated in Africa; decades later, caused large outbreaks in the Pacific, and is considered endemic in Asia. We aim to describe ZIKV disease epidemiology outside the Americas, the importance of travelers as sentinels of disease transmission, and discrepancies in travel advisories from major international health organizations. METHODS AND FINDINGS: This descriptive analysis using GeoSentinel Surveillance Network records involves sixty-four travel and tropical medicine clinics in 29 countries. Ill returned travelers with a confirmed or probable diagnosis of ZIKV disease acquired in Africa, Asia and the Pacific seen between 1 January 2012 and 31 December 2016 are included, and the frequencies of demographic, trip, and diagnostic characteristics described. ZIKV was acquired in Asia (18), the Pacific (10) and Africa (1). For five countries (Indonesia, Philippines, Thailand, Vietnam, Cameroon), GeoSentinel patients were sentinel markers of recent Zika activity. Additionally, the first confirmed ZIKV infection acquired in Kiribati was reported to GeoSentinel (2015), and a probable case was reported from Timor Leste (April 2016), representing the only case known to date. Review of Zika situation updates from major international health authorities for country risk classifications shows heterogeneity in ZIKV country travel advisories. CONCLUSIONS: Travelers are integral to the global spread of ZIKV, serving as sentinel markers of disease activity. Although GeoSentinel data are collected by specialized clinics and do not capture all imported cases, we show that surveillance of imported infections by returned travelers augments local surveillance system data regarding ZIKV epidemiology and can assist with risk categorization by international authorities. However, travel advisories are variable due to risk uncertainties.

Epidemiology of musculoskeletal injuries sustained by Naval Special Forces Operators and students.

OBJECTIVES: The aim of this analysis was to describe the incidence and common types of medical chart-reviewed musculoskeletal injuries, among four distinct groups of Naval Special Warfare (NSW) personnel: Sea, Air, and Land (SEAL) Operators, SEAL Qualification Training (SQT) students, Special Warfare Combatant-craft Crewman (SWCC) Operators, and Crewman Qualification Training (CQT) students. DESIGN: Descriptive cross-sectional study. METHODS: Medical records were reviewed for 920 NSW personnel. MSI were described and classified by frequency and incidence; anatomic location; injury type and cause; activity during injury; and potential for prevention. RESULTS: The frequency of MSI was 23.1, 46.5, 31.6, and 17.0 per 100 participants per year among SEAL, SQT, SWCC, and CQT, respectively. Upper extremity MSI were the most common in SEAL, lower extremity MSI were common in the other groups. The most frequent MSI anatomic sub-locations varied across groups (SEAL: shoulder, 21.6% of MSI; SQT: foot and toes, 17.0%; SWCC: lumbopelvic spine, 21.7%; and CQT: knee, 30.3%). Pain/spasm/ache were the most common MSI type in SEAL (29.7%) and SWCC (21.7%), tendonitis/tenosynovitis/tendinopathy was the most common MSI type in SQT (21.0%), and tendonitis/tenosynovitis/tendinopathy and fracture were the most common in CQT (15.2% each). A considerable proportion of MSI were classified as potentially preventable-SEAL: 35.1%, SQT: 53.0%, SWCC: 36.7%, and CQT: 21.2%. CONCLUSIONS: MSI cause considerable morbidity among NSW Operators and students, with distinct patterns of distribution by anatomic location and injury type. Since many injuries may be preventable, targeted interventions may be able to mitigate MSI risk.

Clostridium difficile infection in returning travellers.

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

Surveillance report of Zika virus among Canadian travellers returning from the Americas.

BACKGROUND: Widespread transmission of Zika virus in the Americas has occurred since late 2015. We examined demographic and travel-related characteristics of returned Canadian travellers with Zika infection acquired in the Americas to illuminate risk factors for acquisition and the clinical spectrum. METHODS: We analyzed demographic and travel-related data for returned Canadian travellers who presented to a CanTravNet site between October 2015 and September 2016 for care of Zika virus acquired in the Americas. Data were collected with use of the GeoSentinel Surveillance Network data platform. RESULTS: During the study period, 1118 travellers presented to a CanTravNet site after returning from the Americas, 41 (3.7%) of whom had Zika infection. Zika infection from the Americas was diagnosed at CanTravNet sites as often as dengue (n = 41) over the study period. In the first half of the study period, Zika virus burden was borne by people visiting friends and relatives in South America. In the latter half, coincident with the increased spread of Zika throughout the Caribbean and Central America, Zika virus occurred more often in tourists in the Caribbean. Forty (98%) of the travellers with Zika infection acquired it through probable mosquito exposure, and 1 had confirmed sexual acquisition. Congenital transmission occurred in 2 of 3 pregnancies. Two (5%) of those with Zika had symptoms resembling those of Guillain-Barré syndrome, 1 of whom also had Zika viral meningitis. INTERPRETATION: Even in this small cohort, we observed the full clinical spectrum of acute Zika virus, including adverse fetal and neurologic outcomes. Our observations suggest that complications from Zika infection are underestimated by data arising exclusively from populations where Zika is endemic. Travellers should adhere to mosquito-avoidance measures and barrier protection during sexual activity.

Malaria in travellers returning or migrating to Canada: surveillance report from CanTravNet surveillance data, 2004-2014.

BACKGROUND: Malaria remains the most common specific cause of fever in returned travellers and can be life-threatening. We examined demographic and travel correlates of malaria among Canadian travellers and immigrants to identify groups for targeted pretravel intervention. METHODS: Descriptive data on ill returned Canadian travellers and immigrants presenting to a CanTravNet site between 2004 and 2014 with a diagnosis of malaria were analyzed. Data were collected using the GeoSentinel data platform. This network comprises 63 specialized travel and tropical medicine clinics, including 7 Canadian sites (Vancouver, Calgary, Toronto, Ottawa, Winnipeg and Montréal), that contribute anonymous, delinked, clinician- and questionnaire-based travel surveillance data on all ill travellers examined to a centralized Structure Query Language database. RESULTS: During the study period, 20 345 travellers and immigrants were evaluated, and 93% had a travel-related diagnosis. Of these, 437 (2.1%) patients received 456 malaria diagnoses, the most common species being Plasmodium falciparum (n = 282, 61.8%). People travelling to visit friends and relatives were most well-represented (n = 169, 38.7%), followed by business travellers (n = 71, 16.2%). Sub-Saharan Africa was the most common source region, accounting for 341 (74.8%) malaria diagnoses, followed by South Central Asia (n = 55, 12%). Nigeria was the most well-represented source country, accounting for 41 cases (9.0%). India, a high-volume destination for Canadians, accounted for 40 cases (8.8%), 36 of which were caused by Plasmodium vivax. Of 456 malaria diagnoses, 26 (5.7%) were severe. Of 377 nonimmigrant travellers with malaria, 19.9% (n = 75) travelled for less than 2 weeks, and 7.2% (n = 27) travelled for less than 1 week. INTERPRETATION: This analysis provides an epidemiologic framework for Canadian practitioners encountering prospective and returned travellers. It confirms the importance of preventive measures and surveillance associated with travel to sub-Saharan Africa and India, particularly by travellers visiting friends or relatives. Short-duration travel confers important malaria risk.