Four Cryptosporidium spp. and 6 C. hominis subtypes were isolated from 102 of 6,284 patients in 3 pediatric hospitals in People’s Republic of China. A cryptosporidiosis outbreak was identified retrospectively. The outbreak lasted >1 year and affected 51.4% of patients in 1 hospital ward, where 2 C. hominis subtypes with different virulence were found.

Malaria vaccine design and prioritization has been hindered by the lack of a mechanistic correlate of protection. We previously demonstrated a strong association between protection and merozoite-neutralizing antibody responses following vaccination of non-human primates against Plasmodium falciparum reticulocyte binding protein homolog 5 (PfRH5). Here, we test the mechanism of protection. Using mutant human IgG1 Fc regions engineered not to engage complement or FcR-dependent effector mechanisms, we produce merozoite-neutralizing and non-neutralizing anti-PfRH5 chimeric monoclonal antibodies (mAbs) and perform a passive transfer- P. falciparum challenge study in Aotus nancymaae monkeys. At the highest dose tested, 6/6 animals given the neutralizing PfRH5-binding mAb c2AC7 survive the challenge without treatment, compared to 0/6 animals given non-neutralizing PfRH5-binding mAb c4BA7 and 0/6 animals given an isotype control mAb. Our results address the controversy regarding whether merozoite-neutralizing antibody can cause protection against P. falciparum blood-stage infections, and highlight the quantitative challenge of achieving such protection.

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The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle’s digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas.

Neurocysticercosis (NCC), the infection of the human central nervous system (CNS) with larval cysts of causes widespread neurological morbidity. Animal models are crucial for studying the pathophysiology and treatment of NCC. Some drawbacks of current NCC models include differences in the pathogenesis of the model and wild-type parasite, low rates of infection efficiency and lack of reproducibility. We describe a novel porcine model that recreates infection in the CNS with high efficiency. Activated oncospheres, either in a high (45,000-50,000) or low (10,000) dose were inoculated in the common carotid artery of 12 pigs by ultrasound-guided catheterization. Following oncosphere injection, either a high (30 mL) or low (1-3 mL) volume of saline flush was also administered. Cyst burden in the CNS was evaluated independently according to oncosphere dose and flush volume. Neurocysticercosis was achieved in 8/12 (66.7%) pigs. Cyst burden in the CNS of pigs was higher in the high versus the low oncosphere dose category (median: 4.5; interquartile ranges [IQR]: 1-8 and median: 1; IQR: 0-4, respectively) and in the high versus the low flush volume category (median 5.5; IQR: 1-8 and median: 1; IQR: 0-2, respectively), although not statistically different. All cysts in the CNS were viable, whereas both viable and degenerated cysts were found in the musculature. Carotid injection of activated oncospheres in pigs is effective in reproducing NCC. Oncosphere entry into the CNS by way of vasculature mimics wild-type infection, and provides a useful alternative for future investigations on the pathogenesis and antiparasitic treatment of NCC.