Ivermectin and moxidectin against soil-transmitted helminth infections

Moxidectin versus Ivermectin in the prevention and treatment of acute and chronic experimental trichinellosis

The limited activity of the traditional medications against T. spiralis encysted larvae handicaps complete cure of trichinellosis till now due to decreased permeability and absorption through tissues. MOX is listed worldwide for prevention and treatment of several internal and external nematodes. Consequently, the aim of this work was to investigate the effect of moxidectin versus ivermectin on experimental acute and chronic trichinellosis and to illuminate the potential mechanisms of their effects. 105 Mice were divided into four groups; Group I: Uninfected healthy control; Group II: Infected untreated control; Group III: Infected and treated with IVM and Group IV: Infected and treated with MOX. The groups (II, III and IV) were later subdivided equally into three subgroups (a, b, and c) according to the stage of treatment. Parasitological counting of adults and larvae besides immune-histopathological examination of intestines and muscles were done. Results exhibited that both IVM and MOX succeeded in reducing adults and larvae counts with higher potential of MOX in both intestinal and muscle phase. The preeminence of MOX was indicated by decreased inflammation, a significant reduction in the microvascular density (CD31 immunostaining) as well as a reduction in the percentage of fibroblast activation protein (FAP) immunostaining in muscle tissues. Accordingly, the current work recommends moxidectin as an innovative treatment for trichinellosis.

Strongyloidiasis

Strongyloidiasis is a neglected tropical disease caused primarily by the roundworm Strongyloides stercoralis. Strongyloidiasis is most prevalent in Southeast Asia and the Western Pacific. Although cases have been documented worldwide, global prevalence is largely unknown due to limited surveillance. Infection of the definitive human host occurs via direct skin penetration of the infective filariform larvae. Parasitic females reside in the small intestine and reproduce via parthenogenesis, where eggs hatch inside the host before rhabditiform larvae are excreted in faeces to begin the single generation free-living life cycle. Rhabditiform larvae can also develop directly into infectious filariform larvae in the gut and cause autoinfection. Although many are asymptomatic, infected individuals may report a range of non-specific gastrointestinal, respiratory or skin symptoms. Autoinfection may cause hyperinfection and disseminated strongyloidiasis in immunocompromised individuals, which is often fatal. Diagnosis requires direct examination of larvae in clinical specimens, positive serology or nucleic acid detection. However, there is a lack of standardization of techniques for all diagnostic types. Ivermectin is the treatment of choice. Control and elimination of strongyloidiasis will require a multifaceted, integrated approach, including highly sensitive and standardized diagnostics, active surveillance, health information, education and communication strategies, improved water, sanitation and hygiene, access to efficacious treatment, vaccine development and better integration and acknowledgement in current helminth control programmes.

Strongyloidiasis in humans and dogs in Southern Italy: an observational study

Strongyloidiasis is a clinical issue both in humans and in dogs. Moreover, there are concerns about its zoonotic potential. We aimed to explore Strongyloides stercoralis epidemiology in Southern Italy in humans and dogs sharing the same environment in three different settings: (1) kennels (group K); (2) livestock farms (group L) and (3) agricultural farms (group A). For humans, a commercial ELISA test was used for screening. RT-PCR on faecal samples was done for people testing positive or equivocal at serology. On dog's faecal samples, Baermann test and RT-PCR were performed. A total of 145 dogs and 139 persons were tested. Based on faecal tests in dogs and serology in humans, a S. stercoralis positivity of 4.1% and 6.5% was revealed, respectively. The sites where cases were found were different for animals and humans. In dogs the highest positivity was in group K (6.7% against 2% and 0% in L and A). Differently, in humans the proportion of positive results was similar between the groups (p = 0.883). Fifty percent (3/6) of positive dogs were healthy; the other dogs presented weight loss and/or diarrhoea. ELISA-positive persons (n=9) were all in health, but abdominal pain (37.5%), urticaria (22.2%) and asthma (22.2%) were reported, resolving after treatment with oral ivermectin 200 μg/kg. RT-PCR performed on 13 human faecal samples resulted negative. These findings suggest that strongyloidiasis is present in humans and dogs in Southern Italy, and screening in larger cohorts would be needed for more accurate estimates.