In vitro efficacy of anthelmintics on Angiostrongylus cantonensis L3 larvae.

Angiostrongylus cantonensis is the leading cause of eosinophilic meningitis worldwide, with life-threatening complications if not managed correctly. Previous in vitro studies have utilized change in motility patterns of adult female worms to assess the efficacy of anthelmintics qualitatively. However, it is the third stage larvae (L3) that are infectious to humans. With differential staining using propidium iodide penetration as the indicator of death, we can distinguish between dead and live larvae. This assay has enabled us to quantify the in vitro efficacy of nine clinically established anthelmintics on A. cantonensis L3. All drugs were tested at a 1 mm concentration. Piperazine and niclosamide were ineffective in inducing larval death; however, albendazole sulfoxide, pyrantel pamoate, diethylcarbamazine, levamisole and praziquantel were effective as compared to unexposed controls (P < 0.05). Ivermectin and moxidectin did not induce significant levels of mortality, but they considerably reduced larval motility almost immediately. This study indicates the need for further in vivo studies to determine the optimal dose and time frame for post-infection treatment with anthelmintics that demonstrated efficacy.

In vitro comparison of treatments and commercially available solutions on mortality of Angiostrongylus cantonensis third-stage larvae.

On Hawai'i Island, an increase in human neuroangiostrongyliasis cases has been primarily associated with the accidental ingestion of Angiostrongylus cantonensis L3 in snails or slugs, or potentially, from larvae left behind in the slug's slime or feces. We evaluated more than 40 different treatments in vitro for their ability to kill A. cantonensis larvae with the goal of identifying a safe and effective fruit and vegetable wash in order to reduce the risk of exposure. Our evaluation of treatment lethality was carried out in two phases; initially using motility as an indicator of larval survival after treatment, followed by the development and application of a propidium iodide staining assay to document larval mortality. Treatments tested included common household products, consumer vegetable washes and agricultural crop washes. We found minimal larvicidal efficacy among consumer-grade fruit and vegetable washes, nor among botanical extracts such as those from ginger or garlic, nor acid solutions such as vinegar. Alkaline solutions, on the other hand, as well as oxidizers such as bleach and chlorine dioxide, did show larvicidal potential. Surfactants, a frequent ingredient in detergents that lowers surface tension, had variable results, but dodecylbenzene sulfonic acid as a 70% w/w solution in 2-propanol was very effective, both in terms of the speed and the thoroughness with which it killed A. cantonensis L3 nematodes. Thus, our results suggest promising directions for future investigation.

Lidocaine Infusion for Refractory Pain from Rat Lungworm Disease - Honolulu, Hawai'i.

Human infection with Angiostrongyloides cantonensis, or rat lungworm disease, manifests most commonly with neurologic symptoms that often include severe diffuse pain. While pain is reported by the majority of patients with rat lungworm disease, there are presently no published guidelines on the approach to pain management for these patients. Here we report a case of rat lungworm disease where severe refractory pain was the most prominent symptom and an intravenous lidocaine infusion was used as a successful treatment modality. Intravenous lidocaine has been shown to be safe and effective in neuropathic pain, refractory cancer pain, and peri-operative pain management. To our knowledge, this is the first case report on the use of lidocaine infusion for the management of refractory pain from rat lungworm disease, and among the first reports of any approach, to pain management for rat lungworm disease. We suggest that a lidocaine infusion protocol be considered when pain from rat lungworm disease fails to respond to first-line analgesics.

Albendazole-Schisandrin B Co-Therapy on Angiostrongylus cantonensis-Induced Meningoencephalitis in Mice.

Abstract: Currently, Angiostrongylus cantonensis infections are predominantly treated with albendazole. However, the use of albendazole can provoke certain neurological symptoms as a result of the immune response triggered by the dead worms. Therefore, treatment usually involves co-administration of corticosteroids to limit the inflammatory reaction. Corticosteroids play a useful role in suppressing inflammation in the brain; however, long-term usage or high dosage may make it problematic.Schisandrin B, an active ingredient from Schisandra chinensis, has been shown to have anti-inflammatory effects on the brain. This study aimed to investigate the effects and potential of schisandrin B in combination with albendazole to treat Angiostrongylus-induced meningoencephalitis. Here, we show that albendazole-schisandrin B co-treatment suppressed neuroinflammation in Angiostrongylus-infected mice and increased the survival of the mice. Accordingly, albendazole-schisandrin B co-treatment significantly inhibited inflammasome activation, pyroptosis, and apoptosis. The sensorimotor functions of the mice were also repaired after albendazole-schisandrin B treatment. Immune response was shown to shift from Th2 to Th1, which reduces inflammation and enhances immunity against A. cantonensis. Collectively, our study showed that albendazole-schisandrin B co-therapy may be used as an encouraging treatment for Angiostrongylus-induced meningoencephalitis.

Tanshinone IIA attenuates demyelination and promotes remyelination in A. cantonensis-infected BALB/c mice.

BACKGROUND: Angiostrongylus cantonensis infection can cause demyelination in the central nervous system, and there is no effective treatment. METHODS: We used dexamethasone, Tanshinone IIA (TSIIA) and Cryptotanshinone(Two traditional Chinese medicine monomers) in combination with albendazole (AB, a standard anti-helminthic compound) to observe their therapeutic effect on demyelination in A. cantonensis-infected mice. Luxol fast blue staining and electron microscope of myelin sheath, Oligodendrocyte (OL) number and myelin basic protein (MBP) expression in brain was detected in above groups. RESULTS: TSIIA+AB facilitated OL proliferation and significantly increased both myelin sheath thickness and the population of small-diameter axons. In addition, TSIIA treatment inhibited the expression of inflammation-related factors (interleukin [IL]-6, IL-1ß, tumor necrosis factor [TNF]-α, inducible nitric oxide synthase [iNOS]) rather than inhibiting eosinophil infiltration in brain. TSIIA also decreased microglial activation and shifted their phenotype from M1 to M2. CONCLUSIONS: Taken together, these results provide evidence that TSIIA combined with AB may be an effective treatment for demyelination caused by A. cantonensis infection and other demyelinating diseases.

Dexamethasone Downregulates Expressions of 14-3-3ß and γ-Isoforms in Mice with Eosinophilic Meningitis Caused by Angiostrongylus cantonensis Infection.

Steroids are commonly used in patients with eosinophilic meningitis caused by A. cantonensis infections. The mechanism steroids act on eosinophilic meningitis remains unclear. In this mouse experiments, expressions of 14-3-3 isoform ß and γ proteins significantly increased in the CSF 2-3 weeks after the infection, but not increasedin the dexamethasone-treated group. Expression of 14-3-3 ß, γ, ε, and θ isoforms increased in brain meninges over the 3-week period after infection and decreased due to dexamethasone treatment. In conclusion, administration of dexamethasone in mice with eosinophilic meningitis decreased expressions of 14-3-3 isoform proteins in the CSF and in brain meninges.

Severe CNS angiostrongyliasis in a young marine: a case report and literature review.

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis worldwide. Infection typically occurs through ingestion of undercooked molluscs or vegetables contaminated by infective larvae. Endemic regions were previously limited to southeast Asia and the Pacific basin; however, this parasite is seeing an alarming increase in global distribution with reported cases in more than 30 countries, including several states in the USA. Although infection typically results in meningitis, a broad spectrum of CNS involvement and severity is emerging as diagnostic methods (such as real-time PCR) continue to improve diagnosis. In this Grand Round, we report a case of a 20-year-old active duty US marine serving in Okinawa, Japan, afflicted with severe CNS angiostrongyliasis marked by radiculomyelitis with quadriparesis, hyperaesthesia, and urinary retention. We present this case to highlight that no clear guidelines exist for the treatment of severe CNS angiostrongyliasis and provide our consensus recommendation that treatment algorithms include use of dual corticosteroids plus anthelmintics when radicular symptoms are present. In this Grand Round we review the clinical features, epidemiology, advances to diagnostic techniques, and available data on current treatment options for CNS angiostrongyliasis. This diagnosis should be highly considered in the differential diagnosis of a patient presenting with meningeal symptoms, paraesthesia or hyperaesthesia, and CSF eosinophilia so that treatment can be started early, which is particularly important in children, because of their increased risk of severe disease and mortality. We recommend combined therapy with albendazole and prednisolone, with consideration for increased steroid dosing in severe cases.

Neuroangiostrongyliasis: The "Subarachnoid Phase" and Its Implications for Anthelminthic Therapy.

Infection with the Rat Lungworm Angiostrongylus cantonensis is the leading cause of human eosinophilic meningoencephalitis worldwide. From its origins in southeastern Asia, the parasite was spread extensively throughout the twentieth century and is now established in many of the world's warmer regions. Its clinical effects range from mild and transient symptoms, usually headache with peripheral nerve dysfunction, to severe and permanent central nervous system (CNS) damage, occasionally fatal. The severity and prognosis of disease are determined by the larval dose, acquired by ingesting infected intermediate hosts (slugs and snails) or, less often, paratenic hosts, such as crabs, shrimps, frogs, and monitor lizards. Early diagnosis is critical for treatment and depends on clinical suspicion, for laboratory confirmation from blood and cerebrospinal fluid can be delayed and unreliable. Treatment is fraught with difficulty, compounded by conflicting published results. Corticosteroids play a useful role in suppressing early CNS inflammation, but their duration for maintenance becomes problematic in severe infections. Because most of the pathogenesis results from host immuno-inflammatory responses to migrating and dead larvae in the CNS, anthelminthic therapy remains controversial: if effective, it kills viable larvae, arresting them in the CNS and so exacerbating the pathology. In human infections, it is now clear that many larvae do leave the CNS and reach the pulmonary arteries, sometimes with clinical consequences. Pioneering life-cycle studies in rats demonstrated a "subarachnoid phase" in larval development and migration; recent autopsy findings, outlined here, show it also occurs in humans and has some bearing on treatment. One new and four previously reported cases of human infection are analyzed here, with findings indicating that anthelminthic treatment is effective only when given early and should not be commenced beyond 3 weeks after exposure to infection. In endemic areas, treatment should start as soon as this infection is suspected, even without a clear history of exposure, given the unacceptable risks of waiting for diagnostic laboratory confirmation.

Angiostrongylus cantonensis Eosinophilic Meningitis in an Infant, Tennessee, USA.

Angiostrongylus cantonensis, the rat lungworm, is the most common infectious cause of eosinophilic meningoencephalitis worldwide. This parasite is endemic to Southeast Asia and the Pacific Islands, and its global distribution is increasing. We report A. cantonensis meningoencephalitis in a 12-month-old boy in Tennessee, USA, who had not traveled outside of southwestern Tennessee or northwestern Mississippi.

Effects of albendazole combined with TSII-A (a Chinese herb compound) on optic neuritis caused by Angiostrongylus cantonensis in BALB/c mice.

BACKGROUND: Angiostrongylus cantonensis (A. cantonensis) infection can lead to optic neuritis, retinal inflammation, damage to ganglion cells, demyelination of optic nerve and visual impairment. Combined therapy of albendazole and dexamethasone is a common treatment for the disease in the clinic, but it plays no role in vision recovery. Therefore, it has been necessary to explore alternative therapies to treat this disease. Previous studies reported the neuro-productive effects of two constituents of Danshen (a Chinese herb)-tanshinone II-A (TSII-A) and cryptotanshinone (CPT), and this study aims to evaluate the impacts of TSII-A or CPT combined with albendazole on optic neuritis caused by A. cantonensis infection in a murine model. METHODS: To assess the effects of TSII-A or CPT combined with albendazole on optic neuritis due to the infection, mice were divided into six groups, including the normal control group, infection group and four treatment groups (albendazole group, albendazole combined with dexamethasone group, albendazole combined with CPT group and albendazole combined with TSII-A group). The infection group and treatment groups were infected with A. cantonensis and the treatment groups received interventions from 14 dpi (days post infection), respectively. At 21 dpi, the visual acuity of mice in each group was examined by visual evoked potential (VEP). The pathologic alteration of the retina and optic nerve were observed by hematoxylin and eosin (H&E) staining and transmission electronic microscopy (TEM). RESULTS: Infection of A. cantonensis caused prolonged VEP latency, obvious inflammatory cell infiltration in the retina, damaged retinal ganglions and retinal swelling, followed by optic nerve fibre demyelination and a decreasing number of axons at 21 dpi. In treatment groups, albendazole could not alleviate the above symptoms; albendazole combined with dexamethasone lessened the inflammation of the retina, but was futile for the other changes; however, albendazole combined with CPT and albendazole combined with TSII-A showed obvious effects on the recovery of prolonged VEP latency, destruction and reduction of ganglion cells, optic nerve demyelination and axon loss. Compared with albendazole-CPT compound, albendazole combined with TSII-A was more effective. CONCLUSIONS: The current study demonstrates that albendazole combined with TSII-A plays a more effective role in treating optic neuritis caused by A. cantonensis in mice than with dexamethasone, as applied in conventional treatment, indicating that albendazole combined with TSII-A might be an alternate therapy for this parasitic disease in the clinic.

Angiostrongylus cantonensis: tegumental and hypodermic alterations of the fourth-stage larvae following administration of tribendimidine in vivo and in vitro.

Angiostrongylus cantonensis is a parasitic pathogen whose forth-stage larvae (L4) parasitize in the central nervous system (CNS) of the human cause severe eosinophilic encephalitis or meningoencephalitis. Previous study indicated an impressive anthelmintic efficacy of tribendimidine (TBD) against CNS parasitized L4 of A. cantonensis. Tegument of the larvae is the first physical barrier to protect them from attack by the host immune system. In the present study, tegumental and hypodermic alterations were observed by scanning electron microscopy and transmission electron microscopy after administration of TBD. During treatment of TBD in vivo, L4 presented wizened side sensor, disappearance of mastoids and longitudinal grain, prominent surface coat, heterogeneous tegumental layers, incompact hypodermic cell junctions, blurred myotube, and small scale of vacuole in a basal layer. After incubation with TBD in vitro, L4 exhibited a swollen side sensor and mastoids disappearance in head end. Abundant tegumental blebs and obvious deformation of both cross-grain and longitudinal grain were detected on the surface, and shrinkage of all tegumental layers, chaotic cell junction, turbid muscle cell, disappearance of myotubes, and vacuole-like changes were visible under the electron microscope. The results implied the potential mechanism of the anthelmintic effect of tribendimidine against L4 of A. cantonensis by direct damages to tegumental and hypodermic.

Efficacy of tribendimidine against Angiostrongylus cantonensis infection in the mice.

Angiostrongyliasis, also known as eosinophils meningitis, is caused by Angiostrongylus cantonensis parasites in the human central nervous system. Currently, the drug of choice for treatment of angiostrongyliasis is albendazole, but dead worm lysis causes severe inflammatory response, which leads to central nervous system damage. Tribendimidine, a broad-spectrum anti-helmintic drug developed in China, is a derivative of amidantel. This study was designed to test the efficacy of tribendimidine against A. cantonensis in mice. We treated 65 infected female BALB/c mice with tribendimidine or albendazole by oral route. We observed that tribendimidine at doses of 50, 100 and 200 mg/kg/day was effective, and the worm reduction rates were 54.8 %,77.4 %, and 100 % compared with the control group. In addition, the therapeutic effect of early tribendimidine treatment (7 days post-infection [PI]) was better than the late treatment (14 days PI), in comparison with the albendazole group (20 mg/kg/day). The index of therapeutic efficacy included body weight, neurological function, survival time, worm reduction, mRNA levels of proinflammatory cytokines in brain tissue, histopathological examination and electron microscopy scanning. The results showed that tribendimidine could kill the larvae of A. cantonensis in the mice model, and the worm's body wall was observed to be damaged. After treatment with tribendimidine, the survival conditions such as body weight and neurological function were improved, and brain inflammation was reduced in infected mice. This study showed a strong efficacy of tribendimidine against A. cantonensis and provided suitable alternative treatments to further explore its potential use in treatment of human angiostrongyliasis.

The use of albendazole and diammonium glycyrrhizinate in the treatment of eosinophilic meningitis in mice infected with Angiostrongylus cantonensis.

Angiostrongylus cantonensis (A. cantonensis) infection causes eosinophilic meningitis in humans. Eosinophilia and a Th2-type immune response are the crucial immune mechanisms for eosinophilic meningitis. CD4+CD25+ regulatory T cells (Treg) are involved in the pathogenesis of A. cantonensis. Diammonium glycyrrhizinate (DG) is a compound related to glycyrrhizin (GL), a triterpene glycoside extracted from liquorice root. We investigated the curative effects and probable mechanisms of therapy involving a combination of albendazole and DG in BALB/c mice infected with A. cantonensis, and compared these with therapy involving albendazole and dexamethasone. We analysed survival time, body weight, signs, eosinophil numbers, immunoglobulin E (IgE), interleukin-5 (IL-5), and eotaxin concentrations, numbers and Foxp3 expression of CD4+CD25+ Treg, worm recovery and histopathology. The present results demonstrated that the combination of albendazole and DG could increase survival time more efficiently and relieve neurological dysfunction; decrease weight loss, eosinophil numbers, concentrations of IgE, IL-5 and eotaxin, the number and expression of Foxp3 of CD4+CD25+ Treg; and improve worm recovery and histopathology changes in treated animals, compared with the combination of albendazole and dexamethasone. The observations presented here suggest that the albendazole and dexamethasone combination could be replaced by the combination of albendazole and DG.

The mRNA level of the galectin-10 of Angiostrongylus cantonensis induced by reactive oxygen stress.

Galectin plays an important role in host-parasite interactions. In this study, we identified a novel gene encoding galectin-10 (AcGal-10) from the cDNA library of Angiostrongylus cantonensis and characterized its biological role in the parasite. Sequence and phylogeny analysis showed that AcGal-10 is related to other galectin family members with the conserved loci (H(84)-D(86)-R(88)-V(96)-N(98)-W(105)-E(108)-R(110)). The mRNA level of AcGal-10 was expressed in reactive oxygen stress radicals. We have identified two proteins of A. cantonensis galectin-10 gene, one of which was reported (AcGAL10-W) and the others is AcGAL-10-M. In addition, recombinant AcGal-10 (rAcGal-10) was constructed into the pGEX-4T-1 plasmid, purified, and finally confirmed by SDS-PAGE and LC-MS. Hemagglutination assay showed that the minimum concentration of rAcGAL10-W and rAcGAL10-M required for the hemagglutination of BALB/c mice erythrocyte was 25 µg/mL, and the carbohydrate-binding ability showed no difference between rAcGAL10-W and rAcGAL10-M. The mRNA levels of AcGal-10 were indeed expressed higher after stimulation with H(2)O(2) and recombinant A. cantonensis galectin-10. A mutation of AcGal-10 was also found, but there was no significant difference compared with the wild type. Furthermore, we also confirmed that recombinant AcGal-10 plays a role in the activation of the microglia. In conclusion, the report here showed that AcGal-10 may be an important molecule related to infection of A. cantonensis.

Curcumin alleviates eosinophilic meningitis through reduction of eosinophil count following albendazole treatment against Angiostrongylus cantonensis in mice.

Angiostrongylus cantonensis (A. cantonensis) is the most common cause of parasitic eosinophilic meningitis worldwide. By using an animal model of BALB/c mice infected with A. cantonensis, previous studies indicated that the anthelmintic drug, albendazole, could kill A. cantonensis larvae and prevent further infection. However, the dead larvae will induce severe immune responses targeting at brain tissues. To alleviate the detrimental effects caused by the dead larvae, we administered curcumin, a traditional anti-inflammatory agent, as a complementary treatment in addition to albendazole therapy, to determine whether curcumin could be beneficial for treatment. The results showed that although curcumin treatment alone did not reduce worm number, combined treatment by albendazole and curcumin helped to reduce eosinophil count in the cerebrospinal fluid, better than using albendazole alone. This alleviating effect did not affect albendazole treatment alone, since histological analysis showed similar worm eradication with or without addition of curcumin. Nevertheless, curcumin treatment alone and combined albendazole-curcumin treatment did not inhibit MMP-9 expression in the brain tissue. In conclusion, curcumin, when used as a complementary treatment to albendazole, could help to alleviate eosinophilic meningitis through suppression of eosinophil count in the cerebrospinal fluid.

A transcriptomic study on the pepsin-activated infective larvae of Angiostrongylus cantonensis.

To investigate the pepsin-activated infective (third-stage) larvae of Angiostrongylus cantonensis at the transcriptomic level, 1496 ESTs were generated from a cDNA library and clustered into 161 contigs and 757 singletons. Among these unigenes, 54.5% had significant sequence homology with known proteins. The most abundantly expressed transcripts were cathepsin B-like cysteine protease 1 and 2, metalloprotease I, metalloprotease 1 precursor, and extracellular superoxide dismutase. Protein complex was the most common Gene Ontology classification within the 'cellular component' category, embryonic development ending in birth or egg hatching within 'biological process', and protein binding within 'molecular function'. Moreover, 280 clusters were mapped to 158 KEGG pathways and 134 had unique EC numbers. These findings suggest that treatment with pepsin-HCl not only digests the tissues of the snail host but also activates the infective larvae.

The effects of different plant extracts on nematodes.

The anthelminthic efficacy of some differently obtained extracts of several plants was tested in vivo in laboratory animals and in vitro. The extracts were obtained by ethanolic, methanolic, aqueous, or chloroform, respectively, acetonitrile polyethylenglycol (PEG) and/or propylencarbonate (PC) elution at room temperature or at 37°C. The plants used were bulbs of onions, garlic, chives, coconut, birch tree, ananas, cistrose, banana, chicory, date palm fruit, fig, pumpkin, and neem tree seeds. The worm systems tested both in vivo and in vitro were Trichuris muris and Angiostrongylus cantonensis but only in vivo Toxocara cati. The tests clearly showed that the different extraction methods eluted different components and different mass amounts, which had different efficacies against the above-cited worms. In vitro effects against A. cantonensis and T.muris were best with aqueous extracts, followed by chloroform extracts. The other plant extracts showed only low or no effects on A. cantonensis in vitro. In the case of T. muris, best results were obtained in vivo and in vitro with PEG/PC extracts of the onion followed by the aqueous extract of coconut. The complete elimination of worms in the in vivo experiments with T. muris was obtained when infected mice were treated with a 1:1 mixture of extracts of coconut and onion being produced by elutions with a mixture of 1:1 PEG and PC and fed daily for 8 days. T. cati in a naturally infected cat was eliminated by daily oral application of 6 ml coco's fluid for 5 days. This study shows that a broad spectrum of plants has anti-nematodal activities, the intensity of which, however, depends on the mode of extraction. This implicates that, if results should be really comparable, the same extraction methods at the same temperatures have to be used. Furthermore, efficacy in in vitro systems does not guarantee as good--if at all--efficacy in vivo.

Efficacy of combined treatment with albendazole and baicalein against eosinophilic meningitis induced by Angiostrongylus cantonensis in mice.

Angiostrongylus cantonensis infection causes eosinophilic meningitis in humans. Baicalein is a flavonoid originally isolated from the roots of Scutellaria baicalensis Georgi. In this study we evaluated the efficacy of the combination of albendazole and baicalein for treating eosinophilic meningitis in BALB/c mice. Therapeutic efficacy included the survival time, body weight, neurological function, leucocyte and eosinophil counts, eotaxin concentration, matrix metalloproteinase-9 (MMP-9) activity, larval recovery and histopathological examination. The results showed that the combination of albendazole and baicalein was more effective than either drug administered singly. Combination therapy increased the survival time, decreased body weight loss, neurological dysfunction, leucocyte response, eotaxin concentration and MMP-9 activity. Our results suggest that the combination of albendazole and baicalein may exhibit synergistic beneficial effects in the treatment of eosinophilic meningitis induced by A. cantonensis.

Drug target in eosinophilic meningitis caused by Angiostrongylus cantonensis.

Eosinophilic meningitis caused by Angiostrongylus cantonensis is an emerging infectious disease. It is the most common form of human angiostrongyliasis. The diagnosis is made by clinical criteria including the presence of cerebrospinal fluid eosinophils and a history of exposure to A. cantonensis larvae, e.g., from raw freshwater snails or contaminated vegetables. Among various treatment options, corticosteroid is the only effective treatment.

Larvicidal activities of ginger (Zingiber officinale) against Angiostrongylus cantonensis.

In this study, we investigated the anthelmintic activity of [6]-gingerol, [10]-shogaol, [10]-gingerol, [6]-shogaol and hexahydrocurcumin, a constituent isolate from the roots of ginger (Zingiber officinale), for the parasite Angiostrongylus cantonensis. This study found that the above constituents killed A. cantonensis larvae or reduced their spontaneous movements in a time- and dose-dependent manner. The larvicidal effect or ability to halt spontaneous parasite movement of [10]-shogaol, [6]-gingerol, [10]-gingerol, [6]-shogaol and hexahydrocurcumin at various concentrations was reached from 24 to 72 h, respectively. Further investigation to determine minimal effective doses of [10]-gingerol and hexahydrocurcumin revealed [10]-gingerol to have a greater maximum larvicidal effect and loss of spontaneous movements than hexahydrocurcumin, mebendazole and albendazole. These constituents of ginger showed effects against DPPH and peroxyl radical under larvicidal effect. Together, these findings suggest that these constituents of ginger might be used as larvicidal agents against A. cantonensis.