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Treatment of Human Mansoni Schistosomiasis: Comparison Between Praziquantel and Oxamniquine in Brazil
Published in Max J. Miller, E. J. Love, Parasitic Diseases: Treatment and Control, 2020
As shown in Table 1, a total of 769 patients were studied. Males represented 65%. The age ranged from 6 to 72 years, with a mean of 21.9; almost one fifth were children below 15 years old. The average body weight was 53.5 kg. Most of the patients (81%) were living away from endemic areas. The great majority (95%) were chronic cases and 74% presented the intestinal form. The mean number of S. mansoni eggs per gram of feces (EPG) was 325 and the limits were 24 and 3492. Approximately half of the cases eliminated from 100 to 500 eggs and only 20% more than 500 eggs; 7.7% had been previously treated with schistosomicidal agents, the majority with oxamniquine.
The Link Between Immune Responses And Behaviour In Sheep
Published in Husband Alan J., Behaviour and Immunity, 2019
G.R. Gates, L.R. Fell, J.J. Lynch, D.B. Adams, J.P. Barnett, G.N. Hinch, R.K. Munro, H.I. Davies
Animals involved in experiments with immune system challenge were required to have an established immunity. This was achieved by giving an oral infection of 10,000 Haemonchus contortus infective larvae four weeks prior to arena testing. Larvae were given with a drenching gun. This treatment ensured that all animals had a similar immune system status; that is, an acquired immunity to this gastric nematode popularly known as Barber’s Pole Worm. Faecal samples were taken from the animals and results of faecal egg counts revealed that the animals had approximately 200 eggs per gram, indicating that a strong acquired immunity was established in all animals. Six and three days prior to arena testing, those animals which were to be included in an immune system challenge group received a further oral dose of 750 larvae in order to "challenge" their immunity. Doses given at these times are known to produce a reliable effect on behaviour (see Adams et al13). Other sheep were given an oral dose of water at the same times as the challenge groups.
Fasciolopsis
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
Silvia Stefania Longoni, M. Fiamma, B. Paglietti, A. Santona, P.A. Ton Nu
The identification of eggs of F. buski is important for epidemiological surveys and for the monitoring of control interventions. It is difficult to differentiate the eggs of F. buski from the eggs of Fasciola hepatica, which possess less noticeable operculum. At the early stage and in new infection, the feces can be negative at parasitic examination. A period of 3–4 months is necessary for complete maturation of fluke and the production of eggs, but it is not easy to make a diagnosis from stool samples. In the early invasive stage of infection, immunological detection of antibodies and antigens is important for diagnosis. For the identification of F. buski, the Kato-Katz technique for qualitative and semiquantitative diagnosis of intestinal helminthes is useful, and the World Health Organization (WHO) recommends this technique in areas with a moderate to high rate of helminth infections. The number of eggs observed is multiplied by 24 hours to obtain the number of eggs per gram of feces.21
A holistic approach is needed to control the perpetual burden of soil-transmitted helminth infections among indigenous schoolchildren in Malaysia
Published in Pathogens and Global Health, 2020
Nabil A. Nasr, Hesham M. Al-Mekhlafi, Yvonne A. L. Lim, Fatin Nur Elyana, Hany Sady, Wahib M. Atroosh, Salwa Dawaki, Ahmed K. Al-Delaimy, Mona A. Al-Areeqi, Abkar A. Wehaish, Tengku Shahrul Anuar, Rohela Mahmud
In order to detect STH eggs and/or larva, the samples were screened by using different parasitological methods. Upon arrival the samples were screened using direct smear (wet mount) to detect parasites, especially motile larvae and/or protozoan trophozoites. Then, the formalin-ether sedimentation technique was used to examine all the samples. [35] In addition, the Kato–Katz thick smear method was used for the detection of STHs and for the estimation of the intensity of the infections. [36] Egg counting was done, and the intensity of infection was recorded as eggs per gram (epg) of stool and classified according to the WHO guidelines. [36] Moreover, the Harada–Mori culture method was used to detect and determine the concentration of hookworm larvae in light infections [37]. In addition, the samples were examined by the Koga agar plate culture (APC) method in order to detect S. stercoralis [38]. Details about the APC method and results of S. stercoralis among these children has been published elsewhere [39].
Triclabendazole for the treatment of human fascioliasis and the threat of treatment failures
Published in Expert Review of Anti-infective Therapy, 2021
Luis Marcos, Vicente Maco, Angelica Terashima
There have been several clinical trials using TCBZ as a treatment for fascioliasis. Most of them report cure rates in the range of 60–90% using 10–20 mg/kg. For instance, Keiser et al. (2011) reported a cure rate of 68.7% (11/16) with single dose of TCBZ and 75% (3/4) with 20 mg/kg of TCBZ in Egypt [43]. Maco et al. in 2015 reported a cure rate of 95% in children (38/40) using 10 mg/kg single dose and 100% cure rate (44/44) using 15 mg/kg divided into 2 doses 12 h apart, the largest clinical trial in this pediatric population [67]. In Vietnam, a randomized open-label trial showed that 88% (44/50) serological-positive acute fascioliasis patients who received 2 doses of TCBZ 10 mg/kg orally, 12 hours apart with food, met primary endpoint at discharge (resolution of abdominal pain) [68]. Among other clinical trials in Cuba, Bolivia, Egypt, Chile, and Iran, the cure rates were dose-dependent, the higher the dose the higher the cure rate. Cure rates were the highest (above 95.5%) for the 20 mg/kg dose, followed by cure rates of 88% in the 10 mg/kg dose and 50% in the 5 mg/kg dose [59]. There have not been clinical trials of TCBZ using more than 20 mg/kg but in clinical practice, 30–60 mg/kg divided into several days and weeks have been well tolerated in chronic fascioliasis cases and they have achieved cure (negative stool examination up to 90 days post-treatment) in two-thirds of the patients who failed standard-of-care regimens without evidence of re-infection (Terashima unpublished data). This preliminary data suggest that the hypothetical ‘resistance’ may overcome by using longer regimens (more than 3 days) of TCBZ at 10 mg/kg daily but the total length of treatment has not been defined yet. In addition, a stool marker that may show a response to the drug is egg reduction rate (ERR) pre- and post-treatment [43], but may not necessarily be a marker for resistance. Interestingly enough, most of the patients in our experience with failure in multiple regimens of TCBZ have had low intensity of infection (eggs per gram of stools) and this low threshold may not be accurate for ERR analysis.
Dynamics of the bacterial gut microbiota during controlled human infection with Necator americanus larvae
Published in Gut Microbes, 2020
Q. R. Ducarmon, M. A. Hoogerwerf, J. J. Janse, A. R. Geelen, J. P. R. Koopman, R. D. Zwittink, J. J. Goeman, E. J. Kuijper, M. Roestenberg
In the current study, we studied the effect of hookworm infection on the gut microbiota using a longitudinal model for human hookworm infection in healthy volunteers (controlled human hookworm infection model, CHHIM). Here, samples can be obtained at baseline, where the gut microbiome is unperturbed, and longitudinally in order to model the ecosystem’s dynamics and perturbation after exposure to N. americanus. This model allows for studying the changes in the bacterial microbiota in the different stages of infection; skin penetration, (pulmonary) migration and gut establishment, a process which takes roughly four weeks.14 In addition, potential confounding factors which could affect the outcome of studies investigating bacterial-helminth interactions are minimized.13 The power of CHHIM to investigate changes in the human microbiota has been demonstrated in a small study where patients with celiac disease were experimentally infected.15–17 Although a very small study (n = 8), a minor increase in richness was seen after infection, while no changes in community, diversity or abundance of individual taxa occurred.15 This study was however limited by the use of a low infectious inoculum of twenty larvae which resulted in egg output much lower than commonly found in endemic areas and by only including patients with celiac disease.18 In this study we infected individuals with 50–150 L3 larvae, after which we found mean egg counts of around 1500 eggs per gram feces at plateau level, which is more in line with the endemic situation where mild infection is defined by WHO as <2000 eggs per gram feces.18,19 Still, infection levels in CHHIMs are not fully comparable to areas with a high infectious burden, defined as >4000 eggs per gram by WHO. The current study had two main aims. First, to investigate temporal changes in the gut microbiota in response to different dosages (ranging from 50 to 150L3) N. americanus larvae in healthy young volunteers. Second, to investigate temporal differences in the gut microbiota between healthy volunteers experiencing different amounts of clinical symptoms.