Alveolar Echinococcus in a 70-year-old man in Ontario.

Background: Alveolar echinococcus, caused by the tapeworm Echinococcus multilocularis, mimics hepatic malignancy, and carries a mortality rate exceeding 90% in untreated patients. Methods: Diagnosis of E. multilocularis infection is established through clinical, radiographic, and microbiological assessments. Currently available laboratory diagnostics in Ontario are fresh tissue microscopy and histopathology. However, genus-specific Echinococcus enzyme-linked immunosorbent assay (ELISA) serology as well as confirmatory testing with species-specific serology and E. multilocularis polymerase chain reaction (PCR) can be obtained from external reference laboratories. Results: The article presents the first case report of human alveolar echinococcus in Ontario. We outline the multidisciplinary approach of diagnosis as well as surgical and medical management of E. multilocularis infection in a 70-year-old man in Ontario. We describe prior literature of alveolar echinococcus in Canadian settings and highlight its emerging nature with recent human case clusters in the Prairies and reports of E. multilocularis in recent veterinary literature in Ontario. Conclusion: E. multilocularis is an emerging parasitic infection in Canadian settings including Ontario. Clinicians should be aware of the emergence of this invasive infection, especially in those with close contact to canids.

Historique: Causée par le ténia Echinococcus multilocularis, l'échinococcose alvéolaire, qui imite le cancer du foie, est associée à un taux de décès de plus de 90 % chez les patients non traités. Méthodologie: Le diagnostic d'infection par l'E multilocularis est posé par une évaluation clinique, radiographique et microbiologique. La microscopie sur tissus frais et l'histopathologie sont les diagnostics microbiologiques actuellement offerts en Ontario. Cependant, il est possible d'obtenir une analyse sérologique par la méthode d'immunoabsorption enzymatique (ELISA) spécifique du genre Echinococcus ainsi que des tests de confirmation par analyse sérologique spécifique à l'espèce et par amplification en chaîne par polymérase (PCR) de l'E multilocularis auprès de laboratoires de référence externes. Résultats: L'article présente le premier rapport de cas d'échinococcose alvéolaire humaine en Ontario. Les chercheurs soulignent l'approche multidisciplinaire du diagnostic, de même que la prise en charge chirurgicale et médicale de l'infection à E multilocularis chez un homme de 70 ans de l'Ontario. Ils décrivent les publications scientifiques antérieures sur l'échinococcose alvéolaire au Canada et soulignent l'émergence de cette maladie parasitaire dans une récente grappe de cas humains des Prairies, de même que les comptes rendus de cas d'E multilocularis dans les récentes publications vétérinaires de l'Ontario. Conclusion: L'E multilocularis est une infection parasitaire en émergence au Canada, y compris en Ontario. Les cliniciens devraient être informés de l'émergence de cette infection invasive, notamment chez les personnes en contact étroit avec des canidés.

Incidence of Hepatitis C Virus Infections Among Users of Human Immunodeficiency Virus Pre-exposure Prophylaxis.

BACKGROUND & AIMS: Sexual transmission of hepatitis C virus (HCV) is well documented among human immunodeficiency virus (HIV)-uninfected individuals. The use of HIV pre-exposure prophylaxis (PrEP) may be associated with engagement in activities that facilitate the transmission of sexually transmitted infections (STIs) and possibly HCV among PrEP users. METHODS: Between 2012 and 2019, the incidence of HCV and bacterial STIs were calculated among HIV-negative indviduals receiving PrEP at the University Health Network HIV Prevention Clinic. Mucosal, anal, and blood samples were taken to test for HIV, syphilis, and anti-HCV antibodies. RESULTS: Among 344 HIV-uninfected patients receiving PrEP, 86% were men having sex with men (MSM). Five individuals were HCV-antibody positive at the time of PrEP initiation. Serologic and virologic follow-up data were available for 109 HCV-negative individuals over 282 patient-years (PY). Two new infections were recorded, yielding an incidence of primary HCV infection of 0.7 per 100 PY. In contrast with HCV, the incidence rates of chlamydia, gonorrhea, and syphilis were 49.2 per 100 PY, 36.3 per 100 PY, and 5.2 per 100 PY, respectively. Both individuals with new HCV diagnoses reported being MSM with a history of unprotected intercourse and 1 individual also reported recreational drug use. Both individuals were asymptomatic at the time of diagnosis and the infections were detected by routine laboratory monitoring. CONCLUSIONS: The low incidence of HCV infections despite significantly higher rates of other STIs suggests that sexual transmission of HCV is uncommon in HIV-negative MSM PrEP users in this community. Performing routine risk-based HCV surveillance among PrEP users should be evaluated. The high incidence of STIs in this population indicates a vital role for periodic STI monitoring in those receiving PrEP.

Prevalence of Inflammatory Heart Disease Among Professional Athletes With Prior COVID-19 Infection Who Received Systematic Return-to-Play Cardiac Screening.

Importance: The major North American professional sports leagues were among the first to return to full-scale sport activity during the coronavirus disease 2019 (COVID-19) pandemic. Given the unknown incidence of adverse cardiac sequelae after COVID-19 infection in athletes, these leagues implemented a conservative return-to-play (RTP) cardiac testing program aligned with American College of Cardiology recommendations for all athletes testing positive for COVID-19. Objective: To assess the prevalence of detectable inflammatory heart disease in professional athletes with prior COVID-19 infection, using current RTP screening recommendations. Design, Setting, and Participants: This cross-sectional study reviewed RTP cardiac testing performed between May and October 2020 on professional athletes who had tested positive for COVID-19. The professional sports leagues (Major League Soccer, Major League Baseball, National Hockey League, National Football League, and the men's and women's National Basketball Association) implemented mandatory cardiac screening requirements for all players who had tested positive for COVID-19 prior to resumption of team-organized sports activities. Exposures: Troponin testing, electrocardiography (ECG), and resting echocardiography were performed after a positive COVID-19 test result. Interleague, deidentified cardiac data were pooled for collective analysis. Those with abnormal screening test results were referred for additional testing, including cardiac magnetic resonance imaging and/or stress echocardiography. Main Outcomes and Measures: The prevalence of abnormal RTP test results potentially representing COVID-19-associated cardiac injury, and results and outcomes of additional testing generated by the initial screening process. Results: The study included 789 professional athletes (mean [SD] age, 25 [3] years; 777 men [98.5%]). A total of 460 athletes (58.3%) had prior symptomatic COVID-19 illness, and 329 (41.7%) were asymptomatic or paucisymptomatic (minimally symptomatic). Testing was performed a mean (SD) of 19 (17) days (range, 3-156 days) after a positive test result. Abnormal screening results were identified in 30 athletes (3.8%; troponin, 6 athletes [0.8%]; ECG, 10 athletes [1.3%]; echocardiography, 20 athletes [2.5%]), necessitating additional testing; 5 athletes (0.6%) ultimately had cardiac magnetic resonance imaging findings suggesting inflammatory heart disease (myocarditis, 3; pericarditis, 2) that resulted in restriction from play. No adverse cardiac events occurred in athletes who underwent cardiac screening and resumed professional sport participation. Conclusions and Relevance: This study provides large-scale data assessing the prevalence of relevant COVID-19-associated cardiac pathology with implementation of current RTP screening recommendations. While long-term follow-up is ongoing, few cases of inflammatory heart disease have been detected, and a safe return to professional sports activity has thus far been achieved.

Antiretroviral Medications for the Prevention of HIV Infection: A Clinical Approach to Preexposure Prophylaxis, Postexposure Prophylaxis, and Treatment as Prevention.

Preventing new human immunodeficiency virus (HIV) infections is essential to halting the global pandemic. HIV prevention strategies include integrating both nonpharmacologic (eg, safe sexual counseling, circumcision) and pharmacologic approaches. Several pharmacologic HIV prevention strategies are increasingly used globally and include postexposure prophylaxis, preexposure prophylaxis, and treatment as prevention. These prevention modalities have enormous clinical and public health appeal, as they effectively reduce HIV acquisition in individuals and also may lower HIV incidence in communities when integrated and implemented broadly. Efforts are now underway to scale HIV prevention programs using these techniques in both high- and low-resource settings.

Infectious disease implications of large-scale migration of Venezuelan nationals.

Background: The ongoing economic and political crisis in Venezuela has resulted in a collapse of the healthcare system and the re-emergence of previously controlled or eliminated infectious diseases. There has also been an exodus of Venezuelan international migrants in response to the crisis. We sought to describe the infectious disease risks faced by Venezuelan nationals and assess the international mobility patterns of the migrant population. Methods: We synthesized data on recent infectious disease events in Venezuela and among international migrants from Venezuela, as well as on current country of residence among the migrant population. We used passenger-level itinerary data from the International Air Transport Association to evaluate trends in outbound air travel from Venezuela over time. We used two parameter-free mobility models, the radiation and impedance models, to estimate the expected population flows from Venezuelan cities to other major Latin American and Caribbean cities. Results: Outbreaks of measles, diphtheria and malaria have been reported across Venezuela and other diseases, such as HIV and tuberculosis, are resurgent. Changes in migration in response to the crisis are apparent, with an increase in Venezuelan nationals living abroad, despite an overall decline in the number of outbound air passengers. The two models predicted different mobility patterns, but both highlighted the importance of Colombian cities as destinations for migrants and also showed that some migrants are expected to travel large distances. Despite the large distances that migrants may travel internationally, outbreaks associated with Venezuelan migrants have occurred primarily in countries proximate to Venezuela. Conclusions: Understanding where international migrants are relocating is critical, given the association between human mobility and the spread of infectious diseases. In data-limited situations, simple models can be useful for providing insights into population mobility and may help identify areas likely to receive a large number of migrants.

Brief Report: HIV Postexposure Prophylaxis-in-Pocket ("PIP") for Individuals With Low-Frequency, High-Risk HIV Exposures.

BACKGROUND: On-demand preexposure prophylaxis may reduce one's risk of HIV acquisition; however, it is unclear if individuals with a very low frequency of HIV exposures are conferred adequate protection. We evaluated a novel approach dubbed HIV postexposure prophylaxis-in-pocket ("PIP"), for individuals with a low frequency of high-risk HIV exposures. SETTING: Two HIV clinics in Toronto, Canada, managing HIV prevention cases. METHODS: A retrospective evaluation of patients referred to HIV clinics for preexposure prophylaxis between January 1, 2013, and September 30, 2017, inclusive. After counseling and education, selected patients were initiated on PIP if they were having very infrequent HIV exposures. RESULTS: Thirty patients were prescribed PIP. Four patients (13.3%) used PIP during this study. There were no HIV seroconversions in 21.8 cumulative patient-years of PIP. CONCLUSIONS: PIP may be a useful HIV prevention modality for individuals with a very low frequency of HIV exposures.

Sinister seafood: bacteraemia secondary to non-O1/O139 Vibrio cholerae infection.

Introduction.Vibrio species are curved, motile Gram-negative bacilli found in estuarine and marine environments, and are known to cause to gastroenteritis, skin and soft tissue infections, and septicaemia. While not responsible for cholera epidemics, non-O1/O139 Vibrio cholerae (NOVC) is increasingly reported as a cause of gastroenteritis. Case presentation. A 66-year-old man presented to an emergency department with a 1 week history of epigastric pain, emesis and fever. Blood cultures drawn on admission initially demonstrated Gram-negative bacilli, and ultimately grew NOVC, which was later confirmed by matrix-assisted laser desorption ionization-time of flight MS. Subsequent history revealed that the patient had eaten fish and seafood prior to falling ill. He was treated with intravenous ceftriaxone and oral doxycycline while admitted, and oral ciprofloxacin and doxycycline upon discharge. His bacteraemia was believed to be secondary to altered gut anatomy from prior surgery and proton-pump inhibitor use. Conclusion. Risk factors for NOVC bacteraemia include cirrhosis, immunosuppression and other forms of liver disease. Cases are often linked to a history of seafood ingestion when water temperatures rise, enabling Vibrio species to proliferate. While the optimal management of NOVC bacteraemia is unclear, a combination of a third-generation cephalosporin with a tetracycline has been suggested. Physicians should maintain a high index of suspicion for this pathogen when evaluating ill patients with a history of liver disease and seafood ingestion.

Efficacy and Safety of Praziquantel Against Light Infections of Opisthorchis viverrini: A Randomized Parallel Single-Blind Dose-Ranging Trial.

Background: The liver fluke Opisthorchis viverrini, highly prevalent in Southeast Asia, is an important public health burden, including a risk factor for developing an aggressive bile duct cancer, cholangiocarcinoma, in chronically infected patients. Praziquantel, administered at a single 40 mg/kg dose in preventive chemotherapy programs and 3 × 25 mg/kg for individual treatment, is the drug of choice, yet information on the nature of the dose-response relationship is lacking. Methods: We performed a randomized, parallel, single-blind dose-ranging phase 2 trial in the Lao People's Democratic Republic in O. viverrini­infected adults. Patients were randomly assigned to 30 mg/kg, 40 mg/kg, 50 mg/kg, or 3 × 25 mg/kg praziquantel or placebo. Adverse events were recorded at baseline, 3 hours, and 24 hours posttreatment. Cure rates (CRs) and egg reduction rates (ERRs) were estimated 3 weeks after drug administration using available case analysis. Dose-response curves were predicted using Emax models. Results: Two-hundred seventeen O. viverrini­infected patients were assigned to the 5 treatment arms. The majority (94.3%) of patients harbored light infections. The Emax model predicted a high efficacy among the observed dose range. We observed CRs ranging from 92.7% to 95.5% and ERRs >99.5% for all praziquantel treatment groups. Adverse events were mild but higher in the standard treatment group (3 × 25 mg/kg) than in the single-dose treatment arms. Conclusions: Single-dose praziquantel appears to be as efficacious as the standard 3 × 25 mg/kg regimen for the treatment of O. viverrini infections, while presenting fewer adverse events. Further studies are necessary in moderate and heavy O. viverrini infections. Clinical Trials Registration: Randomized Controlled Trials (ISRCTN77186750).

Evaluation of a Urine Pooling Strategy for the Rapid and Cost-Efficient Prevalence Classification of Schistosomiasis.

BACKGROUND: A key epidemiologic feature of schistosomiasis is its focal distribution, which has important implications for the spatial targeting of preventive chemotherapy programs. We evaluated the diagnostic accuracy of a urine pooling strategy using a point-of-care circulating cathodic antigen (POC-CCA) cassette test for detection of Schistosoma mansoni, and employed simulation modeling to test the classification accuracy and efficiency of this strategy in determining where preventive chemotherapy is needed in low-endemicity settings. METHODOLOGY: We performed a cross-sectional study involving 114 children aged 6-15 years in six neighborhoods in Azaguié Ahoua, south Côte d'Ivoire to characterize the sensitivity and specificity of the POC-CCA cassette test with urine samples that were tested individually and in pools of 4, 8, and 12. We used a Bayesian latent class model to estimate test characteristics for individual POC-CCA and quadruplicate Kato-Katz thick smears on stool samples. We then developed a microsimulation model and used lot quality assurance sampling to test the performance, number of tests, and total cost per school for each pooled testing strategy to predict the binary need for school-based preventive chemotherapy using a 10% prevalence threshold for treatment. PRINCIPAL FINDINGS: The sensitivity of the urine pooling strategy for S. mansoni diagnosis using pool sizes of 4, 8, and 12 was 85.9%, 79.5%, and 65.4%, respectively, when POC-CCA trace results were considered positive, and 61.5%, 47.4%, and 30.8% when POC-CCA trace results were considered negative. The modeled specificity ranged from 94.0-97.7% for the urine pooling strategies (when POC-CCA trace results were considered negative). The urine pooling strategy, regardless of the pool size, gave comparable and often superior classification performance to stool microscopy for the same number of tests. The urine pooling strategy with a pool size of 4 reduced the number of tests and total cost compared to classical stool microscopy. CONCLUSIONS/SIGNIFICANCE: This study introduces a method for rapid and efficient S. mansoni prevalence estimation through examining pooled urine samples with POC-CCA as an alternative to widely used stool microscopy.

Assessment of global guidelines for preventive chemotherapy against schistosomiasis and soil-transmitted helminthiasis: a cost-effectiveness modelling study.

BACKGROUND: WHO guidelines recommend annual treatment for schistosomiasis or soil-transmitted helminthiasis when prevalence in school-aged children is at or above a threshold of 50% and 20%, respectively. Separate treatment guidelines are used for these two helminthiases, and integrated community-wide treatment is not recommended. We assessed the cost-effectiveness of changing prevalence thresholds and treatment guidelines under an integrated delivery framework. METHODS: We developed a dynamic, age-structured transmission and cost-effectiveness model that simulates integrated preventive chemotherapy programmes against schistosomiasis and soil-transmitted helminthiasis. We assessed a 5-year treatment programme with praziquantel (40 mg/kg per treatment) against schistosomiasis and albendazole (400 mg per treatment) against soil-transmitted helminthiasis at 75% coverage. We defined strategies as highly cost-effective if the incremental cost-effectiveness ratio was less than the World Bank classification for a low-income country (gross domestic product of US$1045 per capita). We calculated the prevalence thresholds for cost-effective preventive chemotherapy of various strategies, and estimated treatment needs for sub-Saharan Africa. FINDINGS: Annual preventive chemotherapy against schistosomiasis was highly cost-effective in treatment of school-aged children at a prevalence threshold of 5% (95% uncertainty interval [UI] 1·7-5·2; current guidelines recommend treatment at 50% prevalence) and for community-wide treatment at a prevalence of 15% (7·3-18·5; current recommendation is unclear, some community treatment recommended at 50% prevalence). Annual preventive chemotherapy against soil-transmitted helminthiasis was highly cost-effective in treatment of school-aged children at a prevalence of 20% (95% UI 5·4-30·5; current guidelines recommend treatment at 20% prevalence) and the entire community at 60% (35·3-85·1; no guidelines available). When both helminthiases were co-endemic, prevalence thresholds using integrated delivery were lower. Using this revised treatment framework, we estimated that treatment needs would be six times higher than WHO guidelines for praziquantel and two times higher for albendazole. An additional 21·3% (95% Bayesian credible interval 20·4-22·2) of the population changed from receiving non-integrated treatment under WHO guidelines to integrated treatment (both praziquantel and albendazole). Country-specific economic differences resulted in heterogeneity around these prevalence thresholds. INTERPRETATION: Annual preventive chemotherapy programmes against schistosomiasis and soil-transmitted helminthiasis are likely to be highly cost-effective at prevalences lower than WHO recommendations. These findings support substantial treatment scale-up, community-wide coverage, integrated treatment in co-endemic settings that yield substantial cost synergies, and country-specific treatment guidelines. FUNDING: Doris Duke Charitable Foundation, Mount Sinai Hospital-University Health Network AMO Innovation Fund, and Stanford University Medical Scholars Programme.

Diagnosis of Opisthorchis viverrini Infection with Handheld Microscopy in Lao People's Democratic Republic.

Opisthorchiasis is a neglected tropical disease, yet it is of considerable public health importance in Southeast Asia given the predilection for chronically infected persons to develop cholangiocarcinoma. We evaluated a handheld microscope for the diagnosis of Opisthorchis viverrini in a community-based setting in Lao People's Democratic Republic in comparison with conventional light microscopy. In stool samples collected from 104 individuals, handheld microscopy revealed a sensitivity of 70.6% and a specificity of 89.5% for O. viverrini infection. Pearson's correlation for quantitative fecal egg counts between the two devices was 0.98 (95% confidence interval: 0.98-0.99). With small adjustments to further increase diagnostic sensitivity, a handheld microscope may become a helpful tool to screen for O. viverrini and other helminth infections in public health settings.

Sexually transmitted infections and viral hepatitides in patients presenting for non-occupational HIV post-exposure prophylaxis: results of a prospective cohort study.

Data evaluating the screening practices for viral hepatitides and sexually transmitted infections (STIs) in patients presenting for non-occupational HIV post-exposure prophylaxis (nPEP) care are limited. Screening practices and prevalences of viral hepatitides and STIs were evaluated in 126 patients presenting to a dedicated HIV prevention clinic for HIV nPEP. Three patients (2.4%) were diagnosed with chronic hepatitis C infection, 28 (22.2%) did not have surface antibodies in sufficient quantity to confer immunity to hepatitis B, and six (4.8%) were diagnosed with an STI. A multivariate regression model did not predict any demographic or clinical features predictive of HBV non-immunity. Beyond screening for HIV infection, evaluation for viral hepatitides and STIs is an important feature in the care of patients presenting for HIV nPEP.