Improved methods for malaria diagnosis are urgently needed. Here, we evaluate a novel method named rotating-crystal magneto-optical detection (RMOD) in 956 suspected malaria patients in Papua New Guinea. RMOD tests can be conducted within minutes and at low cost. We systematically evaluate the capability of RMOD to detect infections by directly comparing it with expert light microscopy, rapid diagnostic tests and polymerase chain reaction on capillary blood samples. We show that compared to light microscopy, RMOD exhibits 82% sensitivity and 84% specificity to detect any malaria infection and 87% sensitivity and 88% specificity to detect Plasmodium vivax. This indicates that RMOD could be useful in P. vivax dominated elimination settings. Parasite density correlates well with the quantitative magneto-optical signal. Importantly, residual hemozoin present in malaria-negative patients is also detectable by RMOD, indicating its ability to detect previous infections. This could be exploited to reveal transmission hotspots in low-transmission settings.

Acanthamoeba has a worldwide distribution in the environment and it is capable of causing a painful sight-threatening disease of the cornea designated as Acanthamoeba keratitis (AK). Nowadays, the cases of AK have surged all over the world along with its disease burden due to increasing use of contact lenses used not only for optical correction but also for cosmetic purposes. In our present work, epithelial abrasion of a 27-year-old female soft contact lens wearer with keratitis was examined. Genotype identification was carried out with a real-time fluorescence resonance energy transfer polymerase chain reaction (PCR) assay based on sequence analysis of the 18S rRNA gene. Genotyping allowed the identification of a T8 group isolate. The analysis confirmed the importance of a complete diagnostic protocol, including a PCR assay, for the clinical diagnosis of AK from human samples. Acanthamoeba T8 should be considered as potential causative organism in keratitis in human.

In the genus Giardia (G.) intestinalis is the only species found in humans as well as in other mammals, including domestic and farm animals. Molecular characterisation of strains isolated from different hosts revealed the existence of seven major genotypic assemblages. Assemblage A and B isolates have been recovered from a broad range of hosts, including humans, livestock, cats, dogs, beavers and guinea pigs. Infection and subsequent cyst shedding contaminates the environment for all mammals, including humans. In this preliminary investigation we studied the prevalence of Giardia infection in kennel dogs from Hungary by microscopic examinations and using a G. intestinalis Agspecific coproantigen test. In order to investigate the genotypes of Giardia, a nested PCR specific for Giardia 18S-rDNA was introduced. All sequenced samples displayed the sequences described for Assemblage D and C dog-specific G. intestinalis strains. These results indicate, however, that dog giardiosis is highly prevalent in the studied geographical areas, but it doesn't present severe zoonotic potential. In the course of the study, the higher sensitivity of the coproantigen test compared to microscopy, and the significant decline in the infection rate with the increasing age of the dogs sampled was clearly pointed.

We aimed to compare LDH release assay, trypan blue and fluorescent stainings, and non-nutrient Escherichia coli plate assay in determining treatment efficacy of antiamoebic agents against Acanthamoeba castellanii trophozoites/cysts, in vitro. 1BU trophozoites/cysts were challenged with 0.02% polyhexamethylene biguanid (PHMB), 0.1% propamidine isethionate (PD), and 0.0065% miltefosine (MF). Efficacies of the drugs were determined by LDH release and trypan blue assays, by Hoechst 33343, calcein-AM, and ethidium homodimer-1 fluorescent dyes, and by a non-nutrient agar E. coli plate assay. All three antiamoebic agents induced a significant LDH release from trophozoites, compared to controls (p < 0.0001). Fluorescent-dye staining in untreated 1BU trophozoites/cysts was negligible, but using antiamoebic agents, there was 59.3%-100% trypan blue, 100% Hoechst 33342, 0%-75.3% calcein-AM, and 100% ethidium homodimer-1 positivity. On E. coli plates, in controls and MF-treated 1BU trophozoites/cysts, new trophozoites appeared within 24 h, encystment occurred after 5 weeks. In PHMB-and PD-treated 1BU throphozoites/cysts, irregularly shaped, smaller trophozoites appeared after 72 h, which failed to form new cysts within 5 weeks. None of the enzymatic-and dye-based viability assays tested here generated survival rates for trophozoites/cysts that were comparable with those yielded with the non-nutrient agar E. coli plate assay, suggesting that the culture-based assay is the best method to study the treatment efficacy of drugs against Acanthamoeba.

Genus Acanthamoeba is an opportunistic protozoan that is widely distributed in the environment. Within this genus, numerous species are recognized as human pathogens, potentially causing Acanthamoeba keratitis (AK). AK is a corneal disease, associated predominantly with contact lens (CL) wear; its epidemiology is related to the specific Acanthamoeba genotypes. This study reports seven CL wearer, Acanthamoeba PCR-positive patients with AK, diagnosed between January 2015 and 2018. Patients had the diagnosis of AK 1.36 months after first symptoms. Genotyping allowed the identification of six isolates of the T4 and one of the T8 genotypes. At first presentation, pseudendritiformic epithelopathy/dirty epithelium (four eyes, 57.1%), multifocal stromal infiltrates (five eyes, 71.4%), ring infiltrate (three eyes, 42.8%), and perineuritis (one eye, 14.3%) were observed. AK was healed without later recurrence in two eyes (28.5%) using triple-topical therapy, in three eyes (42.8%) following additional penetrating keratoplasty. In one patient (14.3%), AK recurred following successful application of triple-therapy and was treated successfully with repeated triple-topical therapy and in one patient (14.3%), no follow-up data were available after diagnosis. We could not observe correlation of genotype and clinical course or the necessity of corneal transplantation in our case series.