A Machine Learning Model for Evaluating Imported Disease Screening Strategies in Immigrant Populations.

Given the high prevalence of imported diseases in immigrant populations, it has postulated the need to establish screening programs that allow their early diagnosis and treatment. We present a mathematical model based on machine learning methodologies to contribute to the design of screening programs in this population. We conducted a retrospective cross-sectional screening program of imported diseases in all immigrant patients who attended the Tropical Medicine Unit between January 2009 and December 2016. We designed a mathematical model based on machine learning methodologies to establish the set of most discriminatory prognostic variables to predict the onset of the: HIV infection, malaria, chronic hepatitis B and C, schistosomiasis, and Chagas in immigrant population. We analyzed 759 patients. HIV was predicted with an accuracy of 84.9% and the number of screenings to detect the first HIV-infected person was 26, as in the case of Chagas disease (with a predictive accuracy of 92.9%). For the other diseases the averages were 12 screenings to detect the first case of chronic hepatitis B (85.4%), or schistosomiasis (86.9%), 23 for hepatitis C (85.6%) or malaria (93.3%), and eight for syphilis (79.4%) and strongyloidiasis (88.4%). The use of machine learning methodologies allowed the prediction of the expected disease burden and made it possible to pinpoint with greater precision those immigrants who are likely to benefit from screening programs, thus contributing effectively to their development and design.

Screening Program for Imported Diseases in Immigrant Women: Analysis and Implications from a Gender-Oriented Perspective.

The female immigrant population is especially vulnerable to imported diseases. We describe the results of a prospective screening program for imported diseases performed in immigrant female patients. The protocol included tests for HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), Treponema pallidum, Trypanosoma cruzi, Strongyloides stercoralis and Schistosoma spp., intestinal parasites, malaria, and the detection of microfilaremia, according to the patient's origin. Six hundred eleven patients were studied. The most frequent imported diseases were intestinal parasitosis (39.4%), followed by syphilis (14.6%), HIV infection (9%), chronic HCV (5%), and HBV (3.3%). Most of the cases of HIV (78%) and HBV (85%) were diagnosed in patients aged between 16 and 45 years. Hepatitis C virus appeared mostly in patients in the 46- to 65-year range (P = 0.001; odds ratio [OD]: 3.667 [1.741-7.724]) or older than 65 years (P = 0.0001; OR: 26.350 [7.509-92.463]). Syphilis was diagnosed more frequently in patients older than 46 years (P = 0.0001; OR: 4.273 [2.649-6.893]). Multivariate analysis confirmed a greater presence of HCV infection (P = 0.049) and syphilis (P = 0.0001) in patients aged between 46 and 65 years. In 15.4% of patients, screening did not find any pathology. These data show a high prevalence of imported diseases in the female immigrant population, which may have serious consequences in terms of morbimortality and vertical transmission. Our results encourage the establishment of policies of active screening both in women of childbearing age and within the specific pregnancy screening programs.

Imported strongyloidiasis: Data from 1245 cases registered in the +REDIVI Spanish Collaborative Network (2009-2017).

BACKGROUND: Imported strongyloidiasis is increasingly being diagnosed in non-endemic areas. The aim of this study was to describe the epidemiological, clinical and microbiological characteristics of patients with imported strongyloidiasis in Spain. METHODOLOGY: This is an observational retrospective study that included all patients diagnosed of strongyloidiasis registered in the +REDIVI Collaborative Network from 2009 to 2017. Demographic, epidemiological and clinical information was collected from the +REDIVI database, and extra information regarding microbiological techniques, treatment and follow-up was requested to participant centers. FINDINGS: Overall, 1245 cases were included. Most of them were immigrants (66.9%), and South America was the most frequent area of origin. Detection of larvae in stool samples was observed in 21.9% of the patients, and serological tests allowed making the diagnosis in the rest of the cases. Eosinophilia was present in 82.2% of cases. Treatment with ivermectin (compared with albendazole) was the most strongly associated factor to achieve the cure (OR 2.34). CONCLUSIONS: Given the long latency of the infection and the risk of developing a severe presentation, screening of S. stercoralis infection should be mandatory in patients coming from or had traveling to endemic areas, especially in those with immunosuppressant conditions.

Serological screening of Chagas disease in an immigrant population in Asturias, Spain proceeding from Chagas-endemic areas.

Population movements from Chagas disease-endemic areas to non-endemic countries due to immigration make the occurrence of this disease in these latter areas possible. We describe the results of a screening programme conducted in an immigrant population from endemic areas, attending the Tropical Medicine Unit of the Hospital Central de Asturias between June 2006 and June 2008. The ID-Chagas antibody test (particle gel immunoassay (PaGIA); DiaMed-ID) was used as a screening assay. We analysed 64 patients, 9 of whom (14%) tested positive for Chagas disease antibodies, a diagnosis that was confirmed in all cases. Six patients came from Bolivia, 2 from Paraguay and 1 from Brazil. Chagas disease is of increasing importance, even in areas with low migratory flows; hence screening programmes for this population group are especially important.