A single oral treatment with mebendazole for the control of Taenia crassiceps larval infections in rats.

A single oral treatment with mebendazole for the control of Taenia crassiceps larval infections in rats. International Journal for Parasitology9: 73–76. Rats infected with Taenia crassiceps larvae were treated with mebendazole. At a sublethal dose level of 50 mg/kg, a single large oral treatment proved to be markedly more effective in killing cysts than the same amount of drug divided into 10 daily smaller doses. Levamisole promoted a vigorous host cellular response to the intraperitoneal cysts, but when incorporated with mebendazole, it did not enhance the action of the latter drug.     

Efficacy and side effects of albendazole currently in use against Ascaris,Trichuris and hookworm among school children in Wondo Genet,southern Ethiopia

Monitoring the efficacy of anthelminthic drugs is essential. The objective of this study was to assess the efficacy of a single oral dose of 400 mg albendazole (ABZ) against the major soil-transmitted helminth (STH) infection in school children, Wondo Genet, southern Ethiopia. A single fresh stool sample was collected from 298 school children and examined using a duplicate smear of the Kato–Katz method. Children positive for STH infections were treated with single oral dose of 400 mg ABZ and re-examined for intestinal helminth infections 21 days post-treatment. The participants were interviewed for symptoms related with the drug uptake 24 h after ABZ treatment. Children positive for Schistosoma mansoni infections were treated with Praziquantel (40 mg/kg of body weight) after an ABZ treatment follow up survey. 51.3%, 49.7%, 44.6% and 88.3% had hookworm, Ascaris lumbricoides, Trichuris trichiura and any intestinal helminth infection, respectively. Cure rates were 97.4% for hookworm, 96.6% for A. lumbricoides and 30.8% for T. trichiura infections. Egg reduction rates (ERRs) were 99.8% for hookworm, 99.9% for A. lumbricoides and 83.1% for T. trichiura infections. Mild and transient symptoms were observed among the participants which were quite frequent. In conclusion, a 400 mg single oral dose of ABZ was effective against hookworm and A. lumbricoides but less efficacious against T. trichiura infection. The drug resulted in high ERRs for hookworm, A. lumbricoides and T. trichiura. Administration of the drug in repeated doses or in combination with other drugs might be necessary.     

Volunteer and clinical studies with carfecillin: a new orally administered ester of carbenicillin.

Blood and urine levels of carbenicillin were measured in 10 healthy volunteers and four patients with renal failure after single and multiple oral dose of carfecillin. Urinary levels after 1000-mg doses in healthy subjects were considered sufficient for treatment of Pseudomonas aeruginosa urinary infections, but the serum levels were too low for chemotherapy of systemic infections with this organism even in severe renal failure. Urinary infections were treated in 35 inpatients with a seven-day course of carfecillin. The infection was eradicated in 21 cases (60%). In 12 cases the pathogen was Ps. aeruginosa, which was eradicated from eight patients (67%). Many patients had severe urinary tract disease. Side effects were virtually absent.     

Clonorchicidal properties of the synthetic trioxolane OZ78

Because the synthetic trioxolane OZ78 is active against the liver fluke Fasciola hepatica, we were motivated to investigate the in vivo and in vitro activity against another liver fluke, namely Clonorchis sinensis. Rats infected with C. sinensis for 2 and 5 wk were treated orally with single doses of OZ78 (75, 150, or 300 mg/kg). Worm burden reductions were assessed against untreated control rats. Scanning electron microscopy (SEM) was used to observe adult C. sinensis after recovery from rats 1-3 days posttreatment with a single 300 mg/kg oral dose of OZ78 and after in vitro exposure to concentrations of 1, 10, and 100 microg/ml of OZ78. A single 300 mg/kg oral dose of OZ78 resulted in worm burden reductions of 78.5% and 98.5% against juvenile and adult C. sinensis, respectively. SEM observations revealed tegumental surface alterations, including blebbing and sloughing. OZ78 emerges as a new compound with a broad spectrum of activity against major foodborne trematode infections.     

Discovery and biological characterization of capromorelin analogues with extended half-lives

New tert-butyl, picolyl and fluorinated analogues of capromorelin (3), a short-acting growth hormone secretagogue (GHS), were prepared as part of a program to identify long-acting GHSs that increase 24-h plasma IGF-1 levels. Compounds 4c and 4d (ACD LogD values >or=2.9) displayed extended plasma elimination half-lives in dogs, primarily due to high volumes of distribution, but showed weak GH secretagogue activities in rats (ED(50)s>10 mg/kg). A less lipophilic derivative 4 (ACD LogD=1.6) exhibited a shorter canine half-life, but stimulated GH secretion in two animal species. Repeat oral dosing of 4 in dogs for 29 days (6 mg/kg) resulted in a significant down-regulation of the post dose GH response and a 60 and 40% increase in IGF-1 levels relative to pre-dose levels at the 8- and 24-h post dose time points. Compound 4 (CP-464709-18) has been selected as a development candidate for the treatment of frailty.     

Trimethoprim-Sulphamethoxazole: Comparative Study in Urinary Infection in Hospital

Trimethoprim is inhibitory for a wide range of bacteria, and when used in combination with a sulphonamide marked synergy has been reported.In order to test its value in the treatment of urinary infections 154 hospital patients with infections of varying severity and due to a wide range of organisms were treated with combinations of sulphamethoxazole and trimethoprim. Combinations of these substances in two different ratios (2:1 and 10:1) were used in 113 patients, and one week after the end of treatment about three-quarters were cured by both combinations. In a second study 106 patients were treated with a sulphamethoxazole-trimethoprim combination (5:1), ampicillin, or sulphadimidine. The cure rate with the 5:1 combination was higher than that found with ampicillin or sulphadimidine both one week after finishing treatment (sulphamethoxazole-trimethoprim 85%, ampicillin 70%, sulphadimidine 40%) and at the fourth- to fifth-week follow-up (sulphamethoxazole-trimethoprim 67%, ampicillin 52%, sulphadimidine 15%).The results obtained with the various sulphamethoxazole–trimethoprim combinations did not indicate that a particular ratio was superior for treating urinary infections in general or for those caused by any particular species of organism.Laboratory studies showed that many bacteria causing urinary infections in hospital were sensitive to trimethoprim, and the therapeutic results could have been largely predicted from a knowledge of the in-vitro sensitivity tests to trimethoprim alone. For example, sulphamethoxazole–trimethoprim in the treatment of Proteus mirabilis infections was less successful than in those due to Escherichia coli, and this finding was clearly reflected in the higher minimal inhibitory concentrations for trimethoprim of Pr. mirabilis.The sulphamethoxazole–trimethoprim combination was simple to administer, free from side-effects, and gave satisfactory results in the treatment of urinary infections that occurred in hospital patients.     

Long-term low-dose co-trimoxazole in prophylaxis of childhood urinary tract infection: bacteriological aspects.

The bacteriological consequences of giving long-term low-dose co-trimoxazole to children to prevent reinfection of the urinary tract were studied. Only six "break-through" infections occurred during 2637 child-months of prophylaxis. The children complied well with treatment. During prophylaxis the number of rectal coliform bacilli recovered was greatly and rapidly reduced, but at least 70% of the surviving coliform organisms remained sensitive to the two components of co-trimoxazole. Changes in sensitivity pattern were evident within a month of starting treatment and the proportion of rectal organisms resistant to sulphonamide or trimethoprim did not increase with time. After stopping co-trimoxazole prophylaxis the number of rectal organisms recoverable returned rapidly to normal, as did their sensitivities to trimethoprim and sulphonamide. Further episodes of urinary tract infection developing after prophylaxis was stopped were caused by organisms sensitive to a wide range of antimicrobial agents, including trimethoprim.     

Randomised double blind trial of single dose doxycycline for treating cholera in adults.

OBJECTIVE--To compare the efficacy of a single dose of doxycycline (200 or 300 mg) with the standard multiple doses of tetracycline in patients with cholera. DESIGN--Randomised double blind controlled trial. Patients were given a single 200 mg dose of doxycycline, a single 300 mg dose of doxycycline, or multiple doses of tetracycline (500 mg, six hourly intervals). SETTING--Hospital in Bangladesh treating diarrhoea. PATIENTS--261 Patients aged over 15 admitted to the hospital with severe dehydration due to acute watery diarrhoea associated with Vibrio cholerae. All vibrios isolated from the stools and rectal swabs of patients, including those patients with prolonged excretion of vibrios, were sensitive to tetracycline. The stools of all patients at admission were negative for shigella and salmonella. INTERVENTIONS--All patients received rapid intravenous acetate solution for the first four hours after admission to hospital. They were then entered in the study and randomised. Oral rehydration was started immediately after the intravenous treatment. If signs of severe dehydration reappeared during oral treatment patients were given rapid intravenous acetate solution until dehydration was fully corrected. MAIN OUTCOME MEASURES--Stool output in first 24 hours and till diarrhoea stopped, total intake of oral rehydration fluid, duration of diarrhoea, and excretion of vibrio after receiving antibiotic treatment. RESULTS--The median stool outputs during the first 24 hours (275 ml/kg body weight) and till diarrhoea stopped (296 ml/kg body weight) were significantly higher in patients receiving 200 mg doxycycline as a single dose than in patients receiving either standard tetracycline (242 ml/kg body weight and 254 ml/kg body weight) or 300 mg doxycycline (226 ml/kg body weight and 255 ml/kg body weight). Similarly, median consumption of oral rehydration solution (18.45 l) was significantly higher in patients receiving 200 mg doxycycline than in patients receiving either 300 mg doxycycline (16.10 l) or standard tetracycline (14.80 l). Almost equal numbers of patients in each group required unscheduled intravenous acetate solution to correct dehydration during antibiotic treatment. Patients treated with doxycycline (low or high dose), however, had more prolonged excretion of bacteria. CONCLUSIONS--A single 300 mg dose of doxycycline is as effective as the standard multiple dose tetracycline treatment for cholera in terms of stool output, duration of diarrhoea, vomiting, and requirement for oral rehydration solution.     

More effective induction of spawning with long-acting GnRH agonist in the shi drum, Umbrina cirrosa L. (Sciaenidae, Teleostei), a valuable candidate for Mediterranean mariculture

Three experiments of spawning induction in shi drum, Umbrina cirrosa L., were performed in six different commercial Italian hatcheries from May to August (water temperatures: 19–29 °C; salinity: 21–37 p.p.t.). In the first experiment, 119 females (1–4.7 kg), subdivided into 29 lots, were injected with a single dose (2, 5, 8, 10, 15 and 20  μ g kg⁻¹ body weight) of short-acting gonadotropin- releasing hormone agonist (GnRHa-S), des-Gly10,[D-Ala6]-LH-RH ethylamide. In the other two experiments, 85 females (0.7–5.8 kg), subdivided into 22 and four lots, were treated with one (40 or 80  μ g kg⁻¹) or three doses (40  μ g kg⁻¹) of long-acting GnRHa (GnRHa-L), respectively. GnRHa-S stimulated spawning in 69% of the 29 treated lots; the number of eggs laid reached a maximum of 130 000 and a weighted mean of 29 200 total eggs kg⁻¹. GnRHa-L elicited a spawning response in 95% of the 22 one-dose treated lots; the number of laid eggs was higher than with GnRHa-S, reaching a maximum of 213 100 and a weighted mean of 59 400 total eggs kg⁻¹. The yield of developing embryos in 67% of the single GnRHa-L treatments was higher (sometimes up to three times) than with GnRHa-S. Triple treatments of the four lots of females with GnRHa-L always resulted in spawning responses; the best result corresponded to a number of total laid eggs of 358 900 eggs kg⁻¹ with a yield of 177 300 developing embryos.     

Controlled trial of methylprednisolone pulses and low dose oral prednisone for the minimal change nephrotic syndrome.

In a multicentre, randomised, prospective trial 89 patients (67 children and 22 adults) with the minimal change nephrotic syndrome were treated with three intravenous pulses of methylprednisolone followed by low dose oral prednisone for six months (group given methylprednisolone) or with high dose oral prednisone for four weeks followed by low dose oral prednisone for five months (control group). Five patients in the group given methylprednisolone and one in the control group did not respond initially. The time to response was shorter in children treated with methylprednisolone. No significant differences between the two groups were observed in the number of patients who relapsed or number of relapses per patient per year. Patients given methylprednisolone tended to relapse earlier than patients in the control group. Side effects related to treatment were significantly fewer in the group given methylprednisolone than in the control group. These data suggest that a short course of methylprednisolone pulses followed by low dose oral prednisone is only marginally less effective than a regimen of high dose oral steroids but can improve the ratio of risk to benefit associated with treatment of the minimal change nephrotic syndrome.     

Control of lone star ticks (Acari: Ixodidae) on Spanish goats and white-tailed deer with orally administered ivermectin

Ivermectin administered orally to Spanish goats, Capra hircus (L.), or to white-tailed deer, Odocoileus virginianus (Zimmerman), was highly effective against lone star ticks, Amblyomma americanum (L.). For Spanish goats, daily oral doses of 20 micrograms/kg resulted in greater than or equal to 2 ppb ivermectin in the blood. This level was sufficient to cause greater than 95% reduction of estimated larvae from feeding ticks. A bioassay with horn flies, Haematobia irritans (L.), was developed to estimate oral intake of ivermectin. Probit analysis of dose-mortality data indicated that a 50% reduction in adult horn fly emergence can be expected when the manure from goats treated orally with ivermectin at 10, 20, 35, and 50 micrograms/kg/d was mixed with untreated cow manure at a rate of 0.345, 0.110, 0.100, and 0.092%, respectively. In studies with white-tailed deer, daily oral doses of 35 and 50 micrograms/kg/d provided 100% control of adult and about 90% control of nymphs that were placed on treated fawns. A single oral dose of 50 micrograms/kg gave greater than 90% control of adult and nymphal ticks attached to treated fawns at the time of drug administration and 70% control of ticks placed on treated deer three days thereafter. When ticks were placed on fawns treated with a single dose of ivermectin (50 micrograms/kg) the engorgement period was longer, ticks were lighter in weight, and females laid fewer eggs than ticks detaching from control fawns. A single oral dose of ivermectin at 20 micrograms/kg prevented about 60% of the adult and nymphal ticks attached at the time of drug administration from engorging, but did not affect other ticks placed on the animals after treatment.     

The future of new oral antibiotics including the quinolones.

It is estimated that more than 110 million dollars'' worth of oral antibiotics will have been sold in Canada in 1987. In the next few years several new oral antimicrobial agents will reach the market, including beta-lactamase inhibitors, cephalosporins, monobactams, erythromycins and quinolones. Most of these new agents have a broader spectrum of antibacterial activity than the presently available oral antibiotics. A few have a longer half-life and can be administered once a day. The new oral drugs, especially the quinolones and possibly beta-lactams, will now be used to treat infections that in the past could be treated only parenterally. Exacerbations of pulmonary infections due to Pseudomonas aeruginosa in cystic fibrosis can now be successfully treated at home with the new quinolones. Osteomyelitis, arthritis, pneumonia and pyelonephritis will most likely be treated at home in the future. In severe infections patients will be admitted to hospital for short courses of parenteral therapy, followed by oral treatment. If used appropriately the new oral agents may lead to new approaches to the treatment of infectious diseases.     

Metabolism of l-Selenomethionine and Selenite by Probiotic Bacteria: In Vitro and In Vivo Studies

Since selenium supplements have been shown to undergo biotransformation in the gut, probiotic treatment in combination with selenium supplements may change selenium disposition. We investigated the metabolism of L-selenomethionine (SeMet) and selenite by probiotic bacteria in vitro and the disposition of selenium after probiotic treatment followed by oral dosing with SeMet and selenite in rats. When SeMet was incubated anaerobically with individual antibiotic-resistant probiotic strains (Streptococcus salivarius K12, Lactobacillus rhamnosus 67B, Lactobacillus acidophilus L10, and Bifidobacterium lactis LAFTI? B94) at 37°C for 24 h, 11-18% was metabolized with 44-80% of SeMet lost being converted to dimethyldiselenide (DMDSe) and dimethylselenide (DMSe). In similar incubations with selenite, metabolism was more extensive (26-100%) particularly by the lactobacilli with 0-4.8% of selenite lost being converted to DMSe and DMDSe accompanied by the formation of elemental selenium. Four groups of rats (n?=?5/group) received a single oral dose of either SeMet or selenite (2 mg selenium/kg) at the time of the last dose of a probiotic mixture or its vehicle (lyoprotectant mixture used to maintain cell viability) administered every 12 h for 3 days. Another three groups of rats (n?=?3/group) received a single oral dose of saline or SeMet or selenite at the same dose (untreated rats). Serum selenium concentrations over the subsequent 24 h were not significantly different between probiotic and vehicle treated rats but appeared to be more sustained (SeMet) or higher (selenite) than in the corresponding groups of untreated rats. Probiotic treated rats given SeMet also had selenium concentrations at 24 h that were significantly higher in liver and lower in kidney than untreated rats given SeMet. Thus, treatment with probiotics followed by SeMet significantly affects tissue levels of selenium.     

Anaerobic balanoposthitis.

To assess the causative role of non-sporing anaerobes in cass of erosive balanoposthitis, anaerobic culture was performed on purulent discharges from 104 patients with penile ulceration, a foul-smelling discharge, and a mixed and motile bacterial flora. Most of 29 culturally confirmed infections were due to mixed anaerobes and eight to single anaerobes. A rapid response to treatment with metronidazole also confirmed the anaerobic cause of the infection. Thus, acute anaerobic balanoposthitis can be readily diagnosed clinically and is easily treated.     

High prevalence of liver and intestinal fluke infections among residents of Savannakhet Province in Laos

The prevalence of liver and intestinal fluke infections was surveyed on residents of Savannakhet Province, Laos. Fecal specimens were collected from a total of 981 residents in 4 Mekong riverside villages and examined by the Kato-Katz thick smear technique. The results revealed that the overall helminth egg positive rate was 84.2%, and the positive rate for small trematode eggs, including Opisthorchis viverrini, heterophyids, or lecithodendriids, was 67.1%. To obtain adult flukes, 38 small trematode egg positive cases were treated with a 20-30 mg/kg single dose of praziquantel and purged. Diarrheic stools were then collected from 29 people and searched for helminth parasites using stereomicroscopes. Mixed infections with O. viverrini and 6 kinds of intestinal flukes were found, namely, Haplorchis taichui, Haplorchis pumilio, Haplorchis yokogawai, Prosthodendrium molenkampi, Phaneropsolus bonnei, and echinostomes. The total number of flukes collected was 7,693 specimens (av. no. per treated person; 265.3). The most common species was O. viverrini, followed by H. taichui, P. molenkampi, echinostomes, H. pumilio, P. bonnei, and H. yokogawai. The results indicate that foodborne liver and intestinal fluke infections are prevalent among residents of Savannakhet Province, Laos.     

Distribution of Sulphonamides in the Mammary Gland of Cows After Intramammary and Intravenous Application

In experiments on cows it has been shown that addition of the tracer dye, Food Green No. 4, to intramammary preparations containing sulphonamide by inspection of cut surfaces directly demonstrates the galactogenic dispersion. By sulphonamide reaction on the cut surface of the udder and quantitative chemical determinations of both the dye and sulphonamide on pieces of gland tissue an identical distribution of the two components has been found. In normal as well as in glands with chronic indurative mastitis an uneven distribution after intramammary infusion has been found. After simultaneous intramammary application of vehicles for sulphonamide intramammary injections containing Food Green No. 4 and intravenous injection of sulphonamide, an uneven distribution of the intramammary preparation but an uniform distribution of the parenterally injected sulphonamide was demonstrated. The results obtained are discussed in relation to the treatment of mastitis in cows and it is concluded that the blockage of the galactogenic dispersion of intramammary infusions by the pathological changes in acute as well as chronic mastitis, indicate systemic treatment with distribution of the drugs by the vascular route.     

Antiviral Activity of a bis-Benzimidazole Against Experimental Rhinovirus Infections in Chimpanzees

The marked antiviral activity of (S,S-1,2-bis(5-methoxy-2-benzimidazolyl)-1,2-ethanediol (Abbott 36683) against rhinoviruses in tissue culture warranted investigation of its antiviral activity in vivo. Antiviral levels in mouse sera were attained with an oral dose as small as 10 mg/kg and detectable antiviral levels of drug were also found in lung, liver, kidney, intestinal contents, and urine of mice given a single 300 mg/kg oral dose. Antiviral serum levels were also obtained when monkeys were given a single oral dose of Abbott 36683. Six chimpanzees were infected with 100 median tissue culture infective dose units (TCID(50)) of rhinovirus 30. Three of the animals were treated with Abbott 36683, 100 mg/kg daily for 4 consecutive days. Virus shedding occurred in the infected controls but could not be demonstrated in the treated animals from postinfection days 1 to 8. Two of the treated animals did, however, shed virus on day 9. The compound was retested in chimpanzees at dosage levels of 15 and 50 mg/kg daily for 4 days. Each animal was challenged with 100 TCID(50) of rhinovirus 49. Partial protection was obtained. In a third trial, a single 100 mg/kg dose of the compound was administered to chimpanzees infected with rhinovirus 44. Virus was isolated from all throat smears taken from treated animals, indicating that at the lowest drug level no protection occurred.     

Therapeutic effect of cimetidine in patients undergoing haemodialysis.

Blood concentrations of cimetidine were measured and the therapeutic effect of the drug assessed patients undergoing maintenance haemodialysis. Thirteen patients were given a single oral 200-mg dose of cimetidine a mean of 2.7 hours before the start of dialysis. Dialysing for 6--12-6 m2 hours led to a mean fall of 71% in blood cimetidine concentration during haemodialysis. Nine patients with various upper gastrointestinal lesions diagnosed endoscopically were treated for up to six weeks with a reduced cimetidine dose of 200 mg 12-hourly; two patients received two courses of treatment. Repeat endoscopy after treatment disclosed satisfactory healing, and the drug did not accumulate. This lower dose regimen is recommended for patients receiving dialysis who develop upper gastrointestinal lesions for which a histamine H2-receptor antagonist is indicated.     

During one year's neuroleptic treatment in rats striatal dopamine receptor blockade decreases but serum prolactin levels remain elevated

Rats were treated for one year with either trifluoperazine dihydrochloride (2.5–3.5 mg/kg/day) or thioridazine dihydrochloride (30–40 mg/kg/day) when prolactin levels were measured in comparison to animals treated acutely with a single oral bolus of the same drugs in approximately the same dose. Serum prolactin levels at the end of the year of neuroleptic treatment with either drug remained elevated compared to those in control animals, and the elevation was no different from that obtained by administration of an equivalent acute single oral bolus. In contrast, the inhibition of apomorphine-induced stereotypy produced by the acute administration of either drug disappeared during chronic treatment, to be replaced after a year's neuroleptic administration by a supersensitive response. Similarly, the increase in dopamine turnover produced by acute neuroleptic administration, evidenced by raised striatal 3, 4-dihydroxy-phenylacetic acid (DOPAC) levels, also disappeared at the end of a year's treatment, when specific binding of ³H-spiperone to striatal homogenates indicated an increased number of dopamine receptors. The disappearance of evidence of blockade of striatal dopamine receptors, which appeared to become supersensitive during a year's chronic treatment with either trifluoperazine or thioridazine, contrasts with the persistence of the effect of these drugs on serum prolactin levels.     

Single Versus Double Dose Praziquantel Comparison on Efficacy and Schistosoma mansoni Re-Infection in Preschool-Age Children in Uganda: A Randomized Controlled Trial

Background

Schistosoma mansoni infection is proven to be a major health problem of preschool-age children in sub-Saharan Africa, yet this age category is not part of the schistosomiasis control program. The objective of this study was to compare the impact of single and double dose praziquantel (PZQ) treatment on cure rates (CRs), egg reduction rates (ERRs) and re-infection rates 8 months later, in children aged 1-5 years living along Lake Victoria, Uganda.

Methodology/Principal Findings

Infected children (n= 1017) were randomized to receive either a single or double dose of PZQ. Initially all children were treated with a single standard oral dose 40 mg/kg body weight of PZQ. Two weeks later a second dose was administered to children in the double dose treatment arm. Side effects were monitored at 30 minutes to 24 hours after each treatment. Efficacy in terms of CRs and ERRs for the two treatments was assessed and compared 1 month after the second treatment. Re-infection with S. mansoni was assessed in the same children 8 months following the second treatment. CRs were non-significantly higher in children treated with two 40 mg/kg PZQ doses (85.5%; 290/339) compared to a single dose (83.2%; 297/357). ERRs were significantly higher in the double dose with 99.3 (95%CI: 99.2-99.5) compared with 98.9 (95%CI: 98.7-99.1) using a single dose, (P = 0.01). Side effects occurred more frequently during the first round of drug administration and were mild and short-lived; these included vomiting, abdominal pain and bloody diarrhea. Overall re-infection rate 8 months post treatment was 44.5%.

Conclusions

PZQ is efficacious and relatively safe to use in preschool-age children but there is still an unmet need to improve its formulation to suit small children. Two PZQ doses lead to significant reduction in egg excretion compared to a single dose. Re-infection rates with S. mansoni 8 months post treatment is the same among children irrespective of the treatment regimen.