scholarly journals Urogenital Schistosomiasis—History, Pathogenesis, and Bladder Cancer

2021 ◽  
Vol 10 (2) ◽  
pp. 205
Author(s):  
Lúcio Lara Santos ◽  
Júlio Santos ◽  
Maria João Gouveia ◽  
Carina Bernardo ◽  
Carlos Lopes ◽  
...  

Schistosomiasis is the most important helminthiasis worldwide in terms of morbidity and mortality. Most of the infections occurs in Africa, which about two thirds are caused by Schistosoma haematobium. The infection with S. haematobium is considered carcinogenic leading to squamous cell carcinoma (SCC) and urothelial carcinoma of the urinary bladder. Additionally, it is responsible for female genital schistosomiasis leading to infertility and higher risk of human immunodeficiency virus (HIV) transmission. Remarkably, a recent outbreak in Corsica (France) drew attention to its potential re-mergence in Southern Europe. Thus far, little is known related to host-parasite interactions that trigger carcinogenesis. However, recent studies have opened new avenues to understand mechanisms on how the parasite infection can lead cancer and other associated pathologies. Here, we present a historical perspective of schistosomiasis, and review the infection-associated pathologies and studies on host–parasite interactions that unveil tentative mechanisms underlying schistosomiasis-associated carcinogenesis.

2021 ◽  
Vol 15 (9) ◽  
pp. e0009789
Author(s):  
Humphrey D. Mazigo ◽  
Anna Samson ◽  
Valencia J. Lambert ◽  
Agnes L. Kosia ◽  
Deogratias D. Ngoma ◽  
...  

Background Schistosoma haematobium causes urogenital schistosomiasis and is widely distributed in Tanzania. In girls and women, the parasite can cause Female Genital Schistosomiasis (FGS), a gynecological manifestation of schistosomiasis that is highly neglected and overlooked by public health professionals and policy makers. This study explored community members’ knowledge, attitudes and perceptions (KAP) on and health seeking behavior for FGS. Methods/Principal findings Using qualitative research methods—including 40 Focus Group Discussions (FGDs) and 37 Key Informant Interviews (KIIs)—we collected data from 414 participants (Males n = 204 [49.3%] and Females n = 210 [50.7%]). The study engaged 153 participants from Zanzibar and 261 participants from Northwestern Tanzania and was conducted in twelve (12) purposively selected districts (7 districts in Zanzibar and 5 districts in northwestern Tanzania). Most participants were aware of urogenital schistosomiasis. Children were reported as the most affected group and blood in urine was noted as a common symptom especially in boys. Adults were also noted as a risk group due to their involvement in activities like paddy farming that expose them to infection. Most participants lacked knowledge of FGS and acknowledged having no knowledge that urogenital schistosomiasis can affect the female reproductive system. A number of misconceptions on the symptoms of FGS and how it is transmitted were noted. Adolescent girls and women presenting with FGS related symptoms were reported to be stigmatized, perceived as having a sexually transmitted infection (STI), and sometimes labeled as “prostitutes”. Health seeking behavior for FGS included a combination of traditional medicine, self-treatment and modern medicine. Conclusion/Significance Community members living in two very different areas of Tanzania exhibited major, similar gaps in knowledge about FGS. Our data illustrate a critical need for the national control program to integrate public health education about FGS during the implementation of school- and community-based mass drug administration (MDA) and with improvement of water, sanitation and hygiene (WASH) facilities.


Parasitology ◽  
2013 ◽  
Vol 140 (4) ◽  
pp. 521-529 ◽  
Author(s):  
E. HELLARD ◽  
D. FOUCHET ◽  
B. REY ◽  
A. MOUCHET ◽  
H. POULET ◽  
...  

SUMMARYTestosterone is involved in the development and expression of physiological, morphological and behavioural traits. High levels are often associated with high infection risk and/or intensity, suggesting a trade-off between sexual traits and immunity. Classically invoked mechanisms are immunological or behavioural, i.e., testosterone increases susceptibility or resistance to parasites via an impact on immunity or modulates behaviours involved in parasite transmission. However, studies report contrasted patterns. Given its modes of action and the diversity of host-parasite interactions, testosterone should not act similarly on all interactions. To reduce host and context diversity, we studied 3 viruses in the same cat population: the aggressively transmitted Feline Immunodeficiency virus (FIV), and the Feline Calicivirus (FCV) and Herpesvirus (FHV) both transmitted during friendly contacts. Testosterone had a strong effect on the probability of being positive to FIV whereas its effect was significantly weaker on FCV and FHV. These findings demonstrate that testosterone can be differentially associated with parasites of the same type (viruses). The difference we observed was consistent with a behavioural-mediated effect (increased aggressiveness), supporting the idea that the testosterone effect on infection risk is at least partially driven by behavioural mechanisms in our system. Further investigations (e.g., individual immunity measures) are required to confirm this hypothesis.


Viruses ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 482 ◽  
Author(s):  
Francesca Di Giallonardo ◽  
Angie N. Pinto ◽  
Phillip Keen ◽  
Ansari Shaik ◽  
Alex Carrera ◽  
...  

Australia’s response to the human immunodeficiency virus type 1 (HIV-1) pandemic led to effective control of HIV transmission and one of the world’s lowest HIV incidence rates—0.14%. Although there has been a recent decline in new HIV diagnoses in New South Wales (NSW), the most populous state in Australia, there has been a concomitant increase with non-B subtype infections, particularly for the HIV-1 circulating recombinant form CRF01_AE. This aforementioned CRF01_AE sampled in NSW, were combined with those sampled globally to identify NSW-specific viral clades. The population growth of these clades was assessed in two-year period intervals from 2009 to 2017. Overall, 109 NSW-specific clades were identified, most comprising pairs of sequences; however, five large clades comprising ≥10 sequences were also found. Forty-four clades grew over time with one or two sequences added to each in different two-year periods. Importantly, while 10 of these clades have seemingly discontinued, the remaining 34 were still active in 2016/2017. Seven such clades each comprised ≥10 sequences, and are representative of individual sub-epidemics in NSW. Thus, although the majority of new CRF01_AE infections were associated with small clades that rarely establish ongoing chains of local transmission, individual sub-epidemics are present and should be closely monitored.


2011 ◽  
Vol 41 (9) ◽  
pp. 925-933 ◽  
Author(s):  
James A. Cotton ◽  
Jennifer K. Beatty ◽  
Andre G. Buret

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Lenka Ulrychová ◽  
Pavel Ostašov ◽  
Marta Chanová ◽  
Michael Mareš ◽  
Martin Horn ◽  
...  

Abstract Background The blood flukes of genus Schistosoma are the causative agent of schistosomiasis, a parasitic disease that infects more than 200 million people worldwide. Proteases of schistosomes are involved in critical steps of host–parasite interactions and are promising therapeutic targets. We recently identified and characterized a group of S1 family Schistosoma mansoni serine proteases, including SmSP1 to SmSP5. Expression levels of some SmSPs in S. mansoni are low, and by standard genome sequencing technologies they are marginally detectable at the method threshold levels. Here, we report their spatial gene expression patterns in adult S. mansoni by the high-sensitivity localization assay. Methodology Highly sensitive fluorescence in situ RNA hybridization (FISH) was modified and used for the localization of mRNAs encoding individual SmSP proteases (including low-expressed SmSPs) in tissues of adult worms. High sensitivity was obtained due to specifically prepared tissue and probes in combination with the employment of a signal amplification approach. The assay method was validated by detecting the expression patterns of a set of relevant reference genes including SmCB1, SmPOP, SmTSP-2, and Sm29 with localization formerly determined by other techniques. Results FISH analysis revealed interesting expression patterns of SmSPs distributed in multiple tissues of S. mansoni adults. The expression patterns of individual SmSPs were distinct but in part overlapping and were consistent with existing transcriptome sequencing data. The exception were genes with significantly low expression, which were also localized in tissues where they had not previously been detected by RNA sequencing methods. In general, SmSPs were found in various tissues including reproductive organs, parenchymal cells, esophagus, and the tegumental surface. Conclusions The FISH-based assay provided spatial information about the expression of five SmSPs in adult S. mansoni females and males. This highly sensitive method allowed visualization of low-abundantly expressed genes that are below the detection limits of standard in situ hybridization or by RNA sequencing. Thus, this technical approach turned out to be suitable for sensitive localization studies and may also be applicable for other trematodes. The results suggest that SmSPs may play roles in diverse processes of the parasite. Certain SmSPs expressed at the surface may be involved in host–parasite interactions. Graphic abstract


2021 ◽  
Vol 37 (5) ◽  
pp. 445-455
Author(s):  
Rogini Runghen ◽  
Robert Poulin ◽  
Clara Monlleó-Borrull ◽  
Cristina Llopis-Belenguer

1988 ◽  
Vol 62 (2) ◽  
pp. 133-140 ◽  
Author(s):  
S. E. Fryer ◽  
A. J. Probert

ABSTRACTThe daily cercarial output of two Nigerian strains of Schistosoma haematobium in sympatric Bulinus truncatus, B. globosus and B. senegalensis was measured at weekly intervals from the start of emission to the snails' death. In all cases cercariae were released throughout the life of the host, with no cases of “self cure”. Patterns of output through the course of infections in B. truncatus and B. senegalensis were similar to those reported for S. haematobium by other workers, with daily production of cercariae rising to a peak within a few weeks of the onset of shedding, then declining until the host's death. In the longer lived B. globosus production was significantly higher, but declined to very low levels after the initial peak; in some individuals cercarial output remained very low, while others showed a second period of high cercarial emission. The relative compatibility of each host-parasite combination is discussed.


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