Prevalence of Trypanosoma cruzi's Discrete Typing Units in a cohort of Latin American migrants in Spain.

Chagas disease is caused by the protozoan Trypanosoma cruzi. This is an endemic disease in the Americas, but increased migration to Europe has made it emerge in countries where it was previously unknown, being Spain the second non endemic country in number of patients. T. cruzi is a parasite with a wide genetic diversity, which has been grouped by consensus into 6 Discrete Typing Units (DTUs) affecting humans. Some authors have linked these DTUs either to a specific epidemiological context or to the different clinical presentations. Our main objective was to describe the T. cruzi DTUs identified from a population of chronically infected Latin American migrants attending a reference clinic in Madrid. 149 patients meeting this condition were selected for the study. Molecular characterization was performed by an algorithm that combines PCR of the intergenic region of the mini exon-gene, the 24Sα and 18S regions of rDNA and the variable region of the satellite DNA. A descriptive analysis was performed and associations between geographical/clinical data and the different DTUs were tested. DTUs could be determined in 105 out of 149 patients, 93.3% were from Bolivia, 67.7% were women and median age was 35 years (IQR 29-44). The most common DTU found was TcV (58; 55.2%), followed by TcIV (17; 16.2%), TcII (10; 9.5%) and TcI (4; 3.8%). TcIII and TcVI were not identified from any patient, and 15.2% patients presented mixed infections. In addition, we determined DTUs after treatment in a subset of patients. In 57% patients had different DTUs before and after treatment. DTUs distribution from this study indicates active transmission of T. cruzi is occurring in Bolivia, in both domestic and sylvatic cycles. TcIV was confirmed as a cause of chronic human disease. The current results indicate no correlation between DTU and any specific clinical presentation associated with Chagas disease, nor with geographical origin. Treatment with benznidazole does not always clear T. cruzi's genetic material from blood, and DTUs detected in the same patient may vary over time indicating that polyparasitism is frequent.

Screening of imported infectious diseases among asymptomatic sub-Saharan African and Latin American immigrants: a public health challenge.

Migrants from developing countries are usually young and healthy but several studies report they may harbor asymptomatic infections for prolonged periods. Prevalence of infections were determined for asymptomatic immigrants from Latin America and sub-Saharan Africa who ettended to a European Tropical Medicine Referral Center from 2000 to 2009. A systematic screening protocol for selected infections was used. Data from 317 sub-Saharan Africans and 383 Latin Americans were analyzed. Patients were mostly young (mean age 29 years); there were significantly more males among sub-Saharan Africans (83% versus 31.6%) and pre-consultation period was longer for Latin Americans (5 versus 42 months). Diagnoses of human immunodeficiency virus (HIV), chronic hepatitis B and C virus infection, and latent tuberculosis were significantly more frequent in sub-Saharan Africans (2.3% versus 0.3%; 14% versus 1.6%; 1.3 versus 0%; 71% versus 32.1%). There were no significant differences in prevalence for syphilis and intestinal parasites. Malaria and schistosomiasis prevalence in sub-Saharan Africans was 4.6% and 5.9%, respectively, and prevalence of Chagas disease in Latin Americans was 48.5%. Identifying and treating asymptomatic imported infectious diseases may have an impact both for the individual concerned and for public health. Based on these results, a systematic screening protocol for asymptomatic immigrants is proposed.

An approach to the management of Trypanosoma cruzi infection (Chagas' disease) in immunocompromised patients.

The epidemiology of Chagas disease has changed in the last decades due to migration movements, population ageing and the emergence of new transmission routes. In endemic countries, health facilities and access to healthcare are improving and T. cruzi infected patients are also benefiting from medical advances. The HIV epidemic has spread to both endemic and non-endemic areas for T. cruzi, organ transplant rates have increased recently, especially in Latin America, and other medical conditions affecting the immune system are increasing their global burden. The natural course of Chagas disease is mainly determined by the host's cellular immune response. These conditions may therefore overlap with T. cruzi infection and alter the disease's natural history which may present with atypical clinical forms and a higher associated morbidity and mortality in immunocompromised patients. The present review aims to contribute to the management of immunosuppressed patients with T. cruzi infection.