Molecular typing of Strongyloides stercoralis in Latin America, the clinical connection

SUMMARYStrongyloides stercoralis is rarely recognized as a major public health issue, probably because its burden is largely underestimated. We reviewed the literature (both PubMed and ‘grey’ literature) about the prevalence of strongyloidiasis in Latin America, an area of presumable high endemicity. There were finally 88 papers involved in the analysis, covering the period between 1981 and 2011. Studies were heterogeneous in several aspects, such as the populations screened and the diagnostic methods used. Most of the studies relied on direct coproparasitological examination, which has low sensitivity for the detection of S. stercoralis larvae. The following countries presented areas of high prevalence (>20%): Argentina, Ecuador, Venezuela, Peru and Brazil. Globally, for most of the included countries it was not possible to define reliable data because of paucity and/or inadequacy of studies. S. stercoralis requires specific diagnostic methods for its detection; therefore, surveys should be specifically designed in order to avoid underestimation of the infection.

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Strongyloides spp. infections of veterinary importance

Parasitology ◽

10.1017/s0031182016001116 ◽

2016 ◽

Vol 144 (3) ◽

pp. 274-284 ◽

Cited By ~ 33

Author(s):

STIG M. THAMSBORG ◽

JENNIFER KETZIS ◽

YOICHIRO HORII ◽

JACQUELINE B. MATTHEWS

Keyword(s):

Molecular Typing ◽

Companion Animals ◽

Geographical Location ◽

Stocking Density ◽

Strongyloides Stercoralis ◽

Domestic Animal ◽

Clinical Disease ◽

Future Research ◽

Prevalence Studies ◽

Primary Means

SUMMARYThis paper reviews the occurrence and impact of threadworms, Strongyloides spp., in companion animals and large livestock, the potential zoonotic implications and future research. Strongyloides spp. infect a range of domestic animal species worldwide and clinical disease is most often encountered in young animals. Dogs are infected with Strongyloides stercoralis while cats are infected with different species according to geographical location (Strongyloides felis, Strongyloides tumefaciens, Strongyloides planiceps and perhaps S. stercoralis). In contrast to the other species, lactogenic transmission is not a primary means of infection in dogs, and S. stercoralis is the only species considered zoonotic. Strongyloides papillosus in calves has been linked to heavy fatalities under conditions of high stocking density. Strongyloides westeri and Strongyloides ransomi of horses and pigs, respectively, cause only sporadic clinical disease. In conclusion, these infections are generally of low relative importance in livestock and equines, most likely due to extensive use of macrocyclic lactone anthelmintics and/or improved hygiene. Future prevalence studies need to include molecular typing of Strongyloides species in relation to different hosts. More research is urgently needed on the potential zoonotic capacity of Strongyloides from dogs and cats based on molecular typing, information on risk factors and mapping of transmission routes.

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

10.1101/852558 ◽

2019 ◽

Author(s):

Ana Requena-Méndez ◽

Joaquin Salas-Coronas ◽

Fernando Salvador ◽

Joan Gomez-Junyent ◽

Judith Villar-Garcia ◽

...

Keyword(s):

Latin America ◽

Immune System ◽

Strongyloides Stercoralis ◽

Cross Sectional Study ◽

Serological Tests ◽

Cross Sectional ◽

Systematic Screening ◽

Migrant Populations ◽

Immunosuppressed Patients ◽

Endemic Areas

AbstractStrongyloidiasis is a prevailing helminth infection ubiquitous in tropical and subtropical areas. However, prevalence data are scarce in migrant populations.This study aims at evaluating the prevalence of S. stercoralis at 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 6 Spanish hospitals. A cross-sectional study was conducted and systematic screening for S. stercoralis infection using serological tests was offered to all eligible participants. The overall seroprevalence of S. stercoralis was 9.04% (95% confidence interval [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). There was only one case (1/14 (7.14%) from an individual from East European countries. The seroprevalence in units attending potentially immunosuppressed patients was significantly lower (5.64%) compared with the seroprevalence in other units of the hospital (10.20%) or Tropical diseases units (13.33%) (p<0.001). Conclusions: We report a hospital-based systematic screening of strongyloidiasis with a 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.Author summaryStrongyloidiasis is an infection caused by the helminth Strongyloides stercoralis which is ubiquitous in tropical and subtropical areas. In the rest of the countries, it is also frequent in migrants coming from tropical and subtropical areas. The disease is more severe when an infected subject has an impaired immune system. Within this study we have evaluated the prevalence of this infection in people being attended in six Spanish hospitals. The prevalence was around 9%, being higher in Africa and Latin America compared with other regions. In addition, the prevalence in patients with an impaired immune system (immunosuppression) was lower compared with people non suffering immunosuppression. These results suggest that the prevalence of strongyloidiasis is quite high among migrants living in Spain and that a screening programme should be designed, particularly in immunosuppressed patients that are at more risk of suffering severe complications of the infection.

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The Genesis and Internal Dynamics of El Salvador's People's Revolutionary Army, 1970–1976

Behavioral and Brain Sciences ◽

10.1017/s0140525x13009850 ◽

2014 ◽

Vol 38 (01) ◽

pp. 102-129

Author(s):

ALBERTO MARTÍN ÁLVAREZ ◽

EUDALD CORTINA ORERO

Keyword(s):

Latin America ◽

El Salvador ◽

Early Years ◽

Left Wing ◽

Internal Dynamics ◽

Internal Coherence ◽

The 1960S

AbstractUsing interviews with former militants and previously unpublished documents, this article traces the genesis and internal dynamics of the Ejército Revolucionario del Pueblo (People's Revolutionary Army, ERP) in El Salvador during the early years of its existence (1970–6). This period was marked by the inability of the ERP to maintain internal coherence or any consensus on revolutionary strategy, which led to a series of splits and internal fights over control of the organisation. The evidence marshalled in this case study sheds new light on the origins of the armed Salvadorean Left and thus contributes to a wider understanding of the processes of formation and internal dynamics of armed left-wing groups that emerged from the 1960s onwards in Latin America.

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