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China was once a country plagued by parasitic diseases. At the beginning of the founding of the People's Republic of China, nearly 80% of the population suffered from parasitic diseases because of poverty and poor sanitary conditions. After nearly 70 years of development, China has made remarkable achievements in the prevention and control of parasitic diseases, and the prevalence of parasitic diseases has been greatly reduced. In addition to organizational leadership from the government and various preventive measures, drug treatment and drug research & development are important and irreplaceable links in prevention and control work. Since the 1950s, China has begun to introduce, produce and imitate antiparasitic drugs from abroad, such as santonin, benzimidazole, and praziquantel. Chinese scientists have also contributed to the optimization of production techniques, improvements in drug formulation, the application in the clinic and the mechanisms of actions of generic drugs. At the same time, China has independently developed tribendimidine (TrBD, a broad spectrum anthelminthic), and its anthelminthic spectrum has been comprehensively studied. It is active against almost 20 parasites, is especially superior to benzimidazoles against Necator americanus, and surpasses the effectiveness of praziquantel against Clonorchis sinensis. In the treatment of tapeworm disease, the traditional Chinese medicines pumpkin seeds and betel nuts have good curative effects for taeniasis. Chinese scientists have explored the action modes and clinical administration methods of pumpkin seeds and betel nuts, which is still the main clinical regimen for the disease. This paper reviews the history and progress of the study of anthelmintics in intestinal helminth infections since the founding of the People's Republic of China and aiming to support clinicians and drug researchers in China and other countries., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Dipilidium caninum infection is a relatively uncommon parasitic infection in children. We present 10 cases treated in our tertiary care hospital during the last 2 years. This parasitosis has a relatively benign course but should be considered in children with gastrointestinal symptoms and eosinophilia. Treatment can be challenging, especially in infancy. Preventative measures are necessary to avoid the spread of the disease.

The efficacy of a novel topical combination formulation of fipronil, (S)-methoprene, eprinomectin and praziquantel against naturally acquired intestinal nematode and cestode infections in cats was evaluated in seven negative control, blinded studies. Cats were selected based on a pre-treatment faecal examination indicating a patent infection with at least hookworms (two studies), Toxocara ascarids (one study), taeniid cestodes (two studies) or Dipylidium cestodes (two studies). In each study, cats were assigned randomly to blocks of two animals each, based on decreasing pre-treatment body weight and were randomly allocated to one of two groups of six to 12 cats: untreated (control) or treated with topical fipronil (8.3%, w/v), (S)-methoprene (10%, w/v), eprinomectin (0.4%, w/v) and praziquantel (8.3%, w/v) (BROADLINE(®), Merial) at 0.12 mL/kg body weight (providing a minimum of 10mg fipronil+12 mg S-methoprene+0.5mg eprinomectin+10mg praziquantel per kg body weight). The topical treatment was administered directly on the skin in the midline of the neck in a single spot once on Day 0. For parasite recovery and count, cats were euthanized humanely and necropsied seven or ten days after treatment. A single treatment with the novel topical combination product provided 91% efficacy against Ancylostoma braziliense, ≥ 99% efficacy against Ancylostoma tubaeforme, and >97% efficacy against Toxocara cati. Similarly, excellent efficacy was established against Taenia taeniaeformis, Dipylidium caninum and Diplopylidium spp. as demonstrated by >97% and up to 100% reductions of cestode counts in the treated cats when compared to the untreated controls (P<0.01). All cats accepted the treatment well based on health observations post-treatment and daily health observations. No adverse experiences or other health problems were observed throughout the studies. The results of this series of controlled studies demonstrated high efficacy and excellent acceptability of the novel topical combination formulation of fipronil, (S)-methoprene, eprinomectin and praziquantel against a broad range of feline intestinal nematode and cestode infections., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

To establish a reliable diagnostic measure for equine Anoplocephala perfoliata infection, the impact of deworming was examined in 12 Thoroughbreds to which bithionol (5-10 mg/kg body weight) was administered and feces were examined by the modified Wisconsin method using sucrose solution. One day after the administration, cestode eggs were detected in previously fecal egg-negative 3 horses and increased in the other 9 horses. The optimum time for post-deworming egg detection was examined in following horses: 17 mares were administered bithionol and 10 mares were used as controls. The fecal egg count was significantly (P<0.01) higher one day after the administration than that on other pre- and post-administration days, while no significant changes occurred in fecal egg count in the controls, demonstrating that one day after bithionol administration is the optimum time for detecting fecal cestode eggs. The diagnostic deworming involving bithionol and fecal examination on the day following administration provides a reliable diagnosis for equine Anoplocephala perfoliata infection.

Bertiella is a frequent parasite in animals, particularly in nonhuman primates. The infestation occurs in man by accidental ingestion of the intermediate host, an acarus containing the cysticercoid larva of Bertiella studeri or Bertiella mucronata. The diagnosis is based on the morphology of the gravid proglottis and eggs with pyriform embryo which is characteristic of the Anoplocephalinae. Human infection is asymptomatic or can induce minor non specific digestive disturbances and the niclosamide is effective in one single dose. The authors report the first case of human bertiellosis in Algeria in a student originating from Yemen.

Dipylidium caninum, the dog tapeworm, is a common intestinal cestode of domestic dogs and cats, but few cases have been reported of human infection by this parasite in Japan. We repot a case of D. caninum infection in a 17 month-old girl, who sometimes had symptoms of abdominal pain, diarrhea, and dysphoria at night. Her mother noted the appearance of small white worms in her stool, and she was seen by a local pediatrician. Despite antiparasitic therapy wiht pyrantel pamoate, the problem persisted and was eventually referred for further workup to Kurume University Hospital. The diagnosis was made by microscopic examination of the excreted proglottids, which contained characteristic egg capsules. She was successfully treated with a singledose of praziquantel and four adult parasites were recovered. The longest intact worm was 32cm. Her family had household pets (a dog and a cat). The pets were seen by the local veterinary and both were evidenced D. caninum. Humans, primarily children, become infected when they accidentally ingest fleas. Parents usually find proglottids as multiple white objects, often described as cucumber, melon, or pumpkin seeds, in stool, diapers, or on the perineum. Most general practitioners and pediatricians may treat children with enterobiasis (pinworm) infection, and in case the treatment fails, other parasite infection should be considered such as this worm. A history of dog or cat pets, fleas, and flea bites may be important clues to diagnosis. Pets found to be infected should also be treated.

Routine anthelmintic treatments are one of the most important components of an equine wellness program used by horse owners and veterinarians today. Thirteen different compounds are available in the United States in the treatment of gastrointestinal parasites, most of which are available over the counter. As a result, there is a decreased reliance on the veterinarian to perform routine tube dewormings. Therefore, the future of the veterinarian's role in the management of gastrointestinal parasites is likely to be in the consultation and design of parasite control programs. With this in mind, this article covers all of the equine anthelmintics and their clinical applications.

The caecum and the adjacent 30 cm lengths of ileum and large colon of 201 horses from two different regions of Norway (Ostlandet and Trøndelag) were examined for the presence of Anoplocephala perfoliata. In all, 20% of the horses were infested with the cestode (27% in Ostlandet and 7% in Trøndelag). The mean number of worms in infected horses from the two regions was 18 and 6, respectively. Information was obtained on the age, sex, breed, type of pasture and anthelmintic treatment after the grazing season for 183 of the 20 horses. The degree of infestation with A. perfoliata was not influenced by age, breed or sex. The odds ratio (confidence limits) for using permanent pastures that had been grazed by horses for at least the 5 last years in succession was 8.8 (3.2-24.4). There was a significantly higher prevalence of A. perfoliata infestation in Ostlandet (odds ration 3.1 (1.1-9.1). The relatively low prevalence of A. perfoliata infestation in Norwegian horses compared to the reported prevalences in other countries and the differences in the prevalence between Ostlandet and Trøndelag are discussed. Gross pathological examination identified lesions such as mucosal thickening, hyperaemia and/or erosions. These lesions were found in all of the infected horses, compared with only 5% of the non-infected horses. Examination of faecal samples from 26 of the infected horses detected cestode eggs in only three cases. It was concluded that faecal examination is an inadequate method for the diagnosis of A. perfoliata infestation.

Increase in travel and immigration has led to a heightened awareness of parasitic diseases among health professionals. Intestinal helminths are important human parasites. Cestodes or tapeworms comprise an important group of helminths. The diagnosis of tapeworm infections requires a skilled laboratory because serological tests are unavailable. In this first part of our review of intestinal helminths, we describe the salient features of the diagnosis and treatment of several important intestinal cestodes, including Diphyllobothrium latum, Taenia, Hymenolepis, and Dipylidium caninum. Niclosamide and praziquantel are the drugs of choice for tapeworm infections.

The authors did not detect any differences in the efficacies and tolerance of praziquantel analogs manufactured by various firms (azinox, Russia; pikitor, China; cesol, cisticide, biltricide, Bayer, Merk, Germany, India). These drugs were found highly effective in opisthorchiasis (87.8%) and schistosomiasis (91.7%) and ineffective in fascioliasis. The efficacy and tolerance of azinox, a drug manufactured in this country, was similar to those of its foreign analogs.

Albendazole (methyl 5-propylthio-1 H-benzimidazol-2-yl carbamate) was used as an anthelmintic in a 3-yr study involving 578 beef cows and 438 nursing calves. Infection levels for nematodes, coccidia, and tapeworm were relatively low throughout the 3-yr period. Eggs per gram of feces in cows and calves were lower (P less than .01) 2 wk posttreatment but were not different 5 mo later, when calves were weaned. Cow weight gain, rate and time of conception, and adjusted calf weaning weights were not affected significantly by deworming of either cows or calves. Level of nematode infection measured as eggs per gram of feces was higher (P less than .01) in younger cows than in mature cows. Although deworming with Albendazole lowered (P less than .01) nematode infection levels, no responses were observed in cow or calf performance.

Praziquantel (EMBAY 8440, Droncit) is a new type of acylated isoquinoline-pyrazine. A single oral or subcutaneous dose of the compound is reliably effective against juvenile and adult cestodes in mice and rats. For the first time, with praziquantel a compound is available that is also effective on cestodes in the bile-duct. Using Hymenolepis nana in mice we were able to show that age, sex, strain and intensity of infestation of the host have no influence on the efficacy. The onset of the effect of praziquantel in vivo is rapid. Within 10 min the parasites were immobilized and contracted and excreted within a few hours with the faeces.

A paste formulation of 3.4% febantel and 0.34% praziquantel was given in soft food at a rate of 0.29 g/kg of body weight, once daily for 3 days to dogs and cats. Eleven of 12 dogs were naturally infected with Ancylostoma caninum, 10 with Trichuris vulpis, 2 with Toxocara canis, 5 with Taenia sp, and 3 with Dirofilaria immitis. Ten of 11 cats were naturally infected with Toxocara cati, 2 with Ancylostoma tubaeforme, 3 with Taenia sp, 5 with Capillaria aerophila, and 1 with Paragonimus kellicotti. Efficacy was 100% for the removal of A caninum, T canis, and Taenia sp and 99.9% in clearance of T vulpis in dogs, and 100% in removal of A tubaeforme, T cati, and Taenia sp in cats. In dogs, Dirofilaria appeared unaffected, and in cats, there was no apparent effect on Capillaria or on Paragonimus. The paste formulation given in soft food was well tolerated and without observable adverse effects.

Febantel was administered as a 3.4% paste to 45 dogs infected with 1 or more nematode species, which included Ancylostoma caninum and Trichuris vulpis. Dosage levels of 5, 10, or 15 mg/kg of body weight daily for 3 consecutive days for a total of 15, 30, or 45 mg/kg were administered. At 15 mg/kg, all dogs were completely cleared of all nematode and cestode infections, including A caninum, T vulpis, Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, Taenia sp, and Dipylidium caninum, except for 1 Physaloptera sp adult. The 2 other dosage levels produced somewhat lower efficacy, with the 5 mg/kg being the least effective. The paste appeared palatable to the dogs and there were no apparent adverse effects.

The anthelmintic activity of and patient tolerance to albendazole, a broad-spectrum anthelmintic, were studied in a multicenter trial involving 480 patients ranging in age from 2 to 60 years. The patients had single or mixed infections caused by pinworms, roundworms, hookworms, whipworms, threadworms, or tapeworms. The stools were examined by the direct method, and ova were counted by means of the Kato-Katz technique. A Graham-Scotch test was also done in patients infected with Enterobius vermicularis. Most patients received a single 400-mg dose of albendazole; adults were given two tablets, and children were given a 2% suspension. All patients with Hymenolepis nana and about half of those with Taenia infections were treated for three successive days. Patients were carefully evaluated before and after treatment to assess the efficacy and safety of the drug. After a single dose of albendazole, the cure rate was 95.3% in ascariasis, 92.2% in ancylostomiasis, 90.5% in trichuriasis, 64.9% in taeniasis, and 100% in enterobiasis. Among patients receiving 400 mg of albendazole for three days, the cure rate was 63.4% in hymenolepiasis and 86.1% in taeniasis. The drug was well tolerated, and no significant side effects were reported.

Although improved sanitation in the United States has resulted in a general diminution in the prevalence of intestinal parasitic infections, some, such as enterobiasis, are not reduced by improved environmental or water sanitation and others, such as amebiasis and hookworm infection, persist in foci. Other infections, notably giardiasis, have increased due to the travels of American tourists in other countries where environmental sanitation is poor. North American physicians, therefore, may expect at some time to have to treat parasitic infections. Favored chemotherapeutic agents currently are: for amebiasis--metronidazole and diiodohydroxyquin; for giardiasis--metronidazole; for tapeworm infections--niclosamide; for enterobiasis--pyrantel pamoate, piperazine citrate, or pyrvinium pamoate; for ascariasis--piperazine citrate; for stronglyoidiasis--thiabendazole; for trichuriasis--mebendazole; for hookworm infection--pyrantel pamoate; for schistosomiasis japonica--tartar emetic; and for schistosomiasis mansoni--niridazole.

Praziquantel was tested against mature (17-day-old) and immature (7-day-old) Raillietina tetragona in experimentally infected chickens using single oral doses of 10, 7.5, 5, or 2.5 mg/kg body wt. The compound showed potent anticestodal activity, with 100% efficacy at 10, 7.5, and 5 mg/kg against immature worms and an efficacy of 100% 97.1%, and 95% against mature worms when given at 10, 5, and 2.5 mg/kg, respectively. Residual worms surviving drug treatment had less biomass than the controls. Praziquantel appears to be well tolerated by chickens, and treated birds showed no clinical reactions at any of the doses tested.

Methyl 5(6)-4-2-pyridyl piperazino carbamoyl benzimidazole-2-carbamate (CDRI Comp. 81-470) was tested against various nematode and cestode infections in different experimental and domestic animals. The compound showed 100% effectivity against adult of Ancylostoma ceylanicum (hookworm) in hamsters (6.25 mg/kg p.o. X 1), Nippostrongylus brasiliensis (trichostrongylid) in rats (100 mg/kg p.o. X 3), Hymenolepis nana (cestode) in rats (25 mg/kg p.o. X 1) and Syphacia obvelata (oxyurid) in mice (12.5 mg/kg p.o. X 3). It was also found highly effective against artificial and natural helminth parasites of higher animals. The compound removed all, A. caninum and A. ceylanicum (hookworms) and Toxocara sp. (ascarid) from dogs at a dose of 10 mg/kg p.o. X 3; A. tubaeformis (hookworm) and Toxocara sp. at 25 mg/kg p.o. X 3 and 2.5 mg/kg p.o. X 3 respectively from cats and Ascaridia galli (ascarid) at 10 mg/kg p.o. X 3 from fowl. The compound in doses of 1500 mg/kg by oral route and 1000 mg/kg by i.p. route did not cause any mortality or produce adverse effect in mice. The expanded anthelmintic action and large therapeutic index indicate compound's great anthelmintic potentiality.