High Prevalence of Strongyloidiasis in Spain: A Hospital-Based Study

Abstract

Introduction: Strongyloidiasis is a prevailing helminth infection ubiquitous in tropical and subtropical areas, however, seroprevalence data are scarce in migrant populations, particularly for those coming for Asia. Methods: This study aims at evaluating the prevalence of S. stercoralis at the hospital level in migrant populations or long term travellers being attended in out-patient and in-patient units as part of a systematic screening implemented in six Spanish hospitals. A cross-sectional study was conducted and systematic screening for S. stercoralis infection using serological tests was offered to all eligible participants. Results: The overall seroprevalence of S. stercoralis was 9.04% (95%CI 7.76-10.31). The seroprevalence of people with a risk of infection acquired in Africa and Latin America was 9.35% (95%CI 7.01-11.69), 9.22% (7.5-10.93), respectively. The number of individuals coming from Asian countries was significantly smaller and the overall prevalence in these countries was 2.9% (95%CI −0.3-6.2). The seroprevalence in units attending Pathogens 2020, 9, 107 2 of 13 potentially immunosuppressed patients was significantly lower (5.64%) compared with other units of the hospital (10.20%) or Tropical diseases units (13.33%) (p < 0.001). Conclusions: We report a hospital-based strongyloidiasis seroprevalence of almost 10% in a mobile population coming from endemic areas suggesting the need of implementing strongyloidiasis screening in hospitalized patients coming from endemic areas, particularly if they are at risk of immunosuppression.

Asymptomatic Strongyloidiasis among Latin American Migrants in Spain: A Community-Based Approach

“…In a recent meta-analysis of the prevalence of strongyloidiasis in migrants from endemic areas who reside in Spain, the authors found an overall prevalence of 14% in Latin Americans [ 30 ]. Our study showed a lower prevalence than that (6% in children and adolescents and 12% in adults; 11% overall), but a similar proportion as another study performed in Spain, where the prevalence was 10.9% in patients from South America [ 3 ].…”

Clinical Features Associated with Strongyloidiasis in Migrants and the Potential Impact of Immunosuppression: A Case Control Study

“…During the study period, 2024 individuals attending six hospitals were screened for strongyloidiasis. Results of the seroprevalence data published elsewhere [ 9 ] showed an overall seroprevalence of S. stercoralis of 9.04% (95%CI 7.76–10.31).…”

“…Individuals at risk of being infected with S. stercoralis were identified (namely those having resided in an endemic country for more than one year, and having attended the hospital for any reason) and a systematic screening for S. stercoralis was offered to patients attending any of the six participating hospitals. This screening was performed in the tropical medicine and international health, transplant, haematology and oncology, pneumology, infectious diseases (including HIV) and systemic diseases departments (including rheumatology and dermatology) of each hospital [ 9 ]. However, it should be added that although not all patients were immunosuppressed, the reasons for hospitalization in those units were always conditions related to such units.…”

“…Therefore, the screening test was offered to those having resided in an endemic country for more than one year and having attended the hospital for any reason. The serological test was a commercial enzyme-linked immunosorbent assay (ELISA), which has been described elsewhere [ 9 ]. A normalized optical density (OD) was used, with an OD/cut-off ratio > 1 being reported as positive.…”

“…The seroprevalence of S. stercoralis can vary substantially depending on the country of origin [ 7 ], with the highest incidence from countries such as Cambodia (36%) or Latin American countries (26%) [ 8 ]. The few studies conducted in migrants coming from endemic areas showed a prevalence above 9% at hospital level [ 9 ], and in studies conducted in non-endemic areas at primary care or community level reported a similar prevalence at around 10% [ 10 , 11 ].…”