Schistosomiasis research paper
Schistosomiasis research paper
PSAC tolerate PZQ well with few reports of adverse effects: normally abdominal pain, vomiting, fatigue, and diarrhoea that resolve within 24 hours [ 98 , , ]. The utility of these along with a proper strategy is important. Is praziquantel sufficient or do we need new drugs? Do trace lines mean that individuals have a light infection, a single sex infection or what? Lygature, a Dutch not-for-profit foundation, acts as the independent coordinator of the Consortium, providing governance in terms of progress, finance and collaboration. Nonetheless, there is a paucity of immunology studies in PSAC detailing the dynamics occurring at the transition of infection from acute to chronic. However, the achievements made have to be sustained and the transition from infection control to transmission control requires guidelines how to proceed [ 32 ].
The non-invasive detection of worm antigens in urine, i. The heart of the matter Even if serious pathology due to schistosomiasis has largely been overcome thanks to preventive chemotherapy, sub-Saharan Africa still includes large areas with high-intensity infection dynamics.
Hycanthone was administered as an injection and seemed ideal but as more and more people were treated a lethal side effect emerged with some individuals suffering from liver necriosis and death. However, further investigations with sensitive diagnostics along the lines used in Morocco [ 31 ] would be required to certify this.
Prevalence of schistosomiasis in africa
One factor which made the SCI so cost effective was the entry of Shin Poong into the praziquantel manufacturing market. In this age group, the impact of gut microbiome dysbiosis on nutritional status is of particular importance. Considerable progress is being made in many endemic countries to reduce morbidity and prevalence of both urinary and intestinal schistosomiasis. This project was funded with resources to assist six countries in Africa. The CCA test has been extensively tested in a number of countries and compared with the Kato Katz stool examination method. However reliable these diagnostics turn out to be at the lab bench, their true utility will be tested in the field. At present, schistosomiasis interventions targeting the microbiome remain theoretical, as mechanistic studies to establish and quantify causal relationships are lacking. Nigeria has the greatest number of cases of schistosomiasis worldwide 3 , with about 29 million infected people, among which 16 million are children, and about million people are at risk of schistosomiasis 2 , 6 , 10 ,
Since the s, praziquantel has been the drug of choice and it remains so, with fortunately little evidence of resistance having developed. Acute and chronic stages of schistosome infection In endemic areas, the acute stage of schistosome infection—including the Katayama syndrome—receives very little research or clinical intervention compared to other areas [ 3233 ].
In Merck KGaA entered the donation field by committing million tablets of praziquantel over 10 years for schistosomiasis control and in they increased their commitment to reach million tablets annually by In another instance, in vitro studies have shown that Salmonella can evade optimal antibiotic treatment by binding to schistosomes using fimbral proteins FimH present on its surface [ 65 ], and that effective treatment of schistosomiasis results in the release of Salmonella, causing septicaemia [ 66 ].
However, these efforts were hampered by the lack of baseline data on the distribution of the disease in a broad scale.
Suitable metrics derived from observed prevalence rates and compared with predetermined thresholds provide insights into exposure-related dynamics [ 33 ]. The aim of the alliance is to promote the best use of donated praziquantel to treat those in need but also to advocate for schistosomiasis control and promote operational research. PSAC are capable of mounting an adaptive immune response to schistosome infections, and a single treatment can illicit this response. Hesham M. However, with at least million people requiring preventive treatment in and Praziquantel was a safe and effective drug, which is still the main control tool available today. The challenge with these non-specific markers particularly is to determine how schistosomiasis influences them; this is a difficult task because even determining the fraction attributable to schistosome infection does not indicate causation. In only Egypt in Africa was offering treatment to the infected and at-risk populations. Thus, even with the low parasite burdens in PSAC, the pro-inflammatory response generated can quickly lead to chronic morbidity [ 60 ].
We also thank members of our research group Parasite Immuno-epidemiology Group at the University of Edinburgh for their comments on drafts of the manuscript. Then the question arises does this level of infection need treating, and if untreated will that individual contribute to transmission?
Existing and new morbidity markers, along with improved multiple diagnostic tools, are useful for targeted disease identification and treatment in PSAC. Owing to existing challenges with the current formulation, there is a need for a paediatric formulation, a better dosing system, a better treatment strategy, and innovative ways of accessing PSAC for treatment.
Epidemiology of schistosomiasis
The Japanese control programme is proof that not only elimination, but even eradication in country, can be achieved by long-term, uninterrupted activities. Poor awareness, recognition, and lack of understanding and quantification of schistosome-associated morbidity has previously made schistosome control in PSAC a lower priority than in older children and adults, but concerted efforts are now beginning to correct this. The author therefore questions whether the timescales to reach eliminations are realistic and whether the tools are available to reach those targets. As made clear by Kajihara and Hirayama [ 26 ], once the epidemiology had been determined, elimination was a straightforward affair with the last new human infection reported in [ 27 ]. They sampled faeces from domestic animals in the fields around a number of villages along the Yangtze River and determined the proportions of Schistosoma-infection in these samples to establish a prediction matrix for each village that could be used to sort them into different types of cluster. However, studies are beginning to shed light on schistosome morbidity in this group, e. PZQ is metabolised by the cytochrome P enzymes as shown in experimental studies [ , ]. These aspects together with any mechanistic pathways are yet to be elucidated. PSAC are capable of mounting an adaptive immune response to schistosome infections, and a single treatment can illicit this response. It contributes with extensive experience in helminths biological and pharmacological research; epidemiology; and clinical research in endemic regions. Box 1.
With growing evidence of genetic diversity for cytochrome P variants in schistosome-endemic regions in Africa [ ], there are implications for PZQ metabolism and treatment efficacy which remain to be elucidated in PSAC.
based on 67 review