[Epidemiological and clinical characteristics of human ocular helaziasis in China from 2011 to 2022 based on bibliometrics].

OBJECTIVE: To understand the clinical and epidemiological characteristics of human ocular thelaziasis patients in China. METHODS: Case reports regarding human ocular thelaziasis cases in China were retrieved in international and national electronic databases, including CNKI, VIP, CBM, Traditional Chinese Medical Literature Analysis and Retrieval System, Wanfang Database, PubMed and Web of Science from 2011 to 2022. Patients' gender, age, clinical symptoms, treatment, recurrence, site of infections, time of onset, affected eye, affected sites, number of infected Thelazia callipaeda, sex of T. callipaeda and source of infections were extracted for descriptive analyses. RESULTS: A total of 85 eligible publications were included, covering 101 cases of human ocular thelaziasis, including 57 males (56.44%) and 44 females (43.56%) and aged from 3 months to 85 years. The main clinical manifestations included foreign body sensation (56 case-times, 22.49%), eye itching (38 case-times, 15.26%), abnormal or increased secretions (36 case-times, 14.46%), tears (28 case-times, 11.24%) and eye redness (28 case-times, 11.24%), and conjunctival congestion (50 case-times, 41.67%) was the most common clinical sign. The most common main treatment (99/101, 98.02%) was removal of parasites from eyes using ophthalmic forceps, followed by administration with ofloxacin and pranoprofen. In publications presenting thelaziasis recurrence, there were 90 cases without recurrence (97.83%) and 2 cases with recurrence (2.17%). Of all cases, 51.96% were reported in four provinces of Hubei, Shandong, Sichuan, Hebei and Henan, and ocular thelaziasis predominantly occurred in summer (42.19%) and autumn (42.19%). In addition, 56.45% (35/62) had a contact with dogs. CONCLUSIONS: The human thelaziasis cases mainly occur in the continental monsoon and subtropical monsoon climate areas such as the Yellow River and the Yangtze River basin, and people of all ages and genders have the disease, with complex clinical symptoms and signs. Personal hygiene is required during the contact with dogs, cats and other animals, and individual protection is required during outdoor activities to prevent thelaziasis.

Live Larva in Ocular Toxocariasis.

This case report describes a finding of a live larva in a patient with a previous diagnosis of ocular toxocariasis.

First report of human Thelazia callipaeda infection in Portugal.

The zoonotic parasitic nematode Thelazia callipaeda, also known as the oriental eye worm, is endemic in several European countries, including Portugal. Infections may result in ocular disease in domestic and wild animals as well as humans, with more or less severe manifestations. We report the first human case of ocular thelaziosis by T. callipaeda in Portugal, a country where the parasite had already been found to infect dogs, cats, red foxes, wild rabbits and a beech marten. An 80-year-old patient from east-central Portugal, who had been suffering from tearing for a few years, had whitish filiform fragments removed from the left eye. Polymerase chain reaction of partial cytochrome c oxidase subunit 1 and 18S small subunit rRNA genes followed by bidirectional sequencing and BLAST analysis confirmed T. callipaeda haplotype 1, the only haplotype previously reported in Europe. The endemicity of T. callipaeda in domestic and wild animals in east-central Portugal makes it very likely that infection of the human patient had occurred locally. In east-central and other geographical areas of Portugal, veterinarians and physicians, especially ophthalmologists, should regard T. callipaeda as a cause of ocular pathology in animals and humans.

Differential Antimicrobial Efficacy of Preservative-Free Contact Lens Disinfection Systems against Common Ocular Pathogens.

Microbial keratitis is a devastating disease that can cause eye damage and blindness and can be the result of infections by several common ocular pathogens. Importantly, some of these pathogens, such as Acanthamoeba, are particularly unsusceptible to biocides in common contact lens care solutions. Therefore, the disinfection efficacy of preservative-free (PF) disinfection systems against bacteria, fungi, and Acanthamoeba trophozoites and cysts should be assessed as products with the most potential to be efficacious against resistant organisms. PF disinfection systems were analyzed for antimicrobial efficacy. These were the one-step (hydrogen peroxide-based) Clear Care and Clear Care Plus systems and the two-step (povidone-iodine-based) Cleadew system. Stand-alone challenges using bacteria, fungi, and Acanthamoeba were prepared according to the International Standards Organization method 14729. These same challenges were also conducted in the presence of the following contact lenses: Boston RGP, Acuvue Oasys, Biofinity, Ultra, and 2-week PremiO. All challenges were performed at the manufacturer's recommended disinfection time. All preservative-free disinfection systems demonstrated similarly high rates of antimicrobial efficacy when challenged with bacteria or fungi, with or without lenses. However, both Clear Care and Clear Care Plus demonstrated significantly greater disinfection efficacy against Acanthamoeba trophozoites and cysts, with and without lenses (P < 0.05). Cleadew efficacy was impacted by the addition of contact lenses, whereas Clear Care/Clear Care Plus maintained similar efficacies in the absence or presence of lenses. While both hydrogen peroxide and povidone-iodine are highly effective against bacteria and fungi, hydrogen peroxide maintains significantly greater disinfection capabilities than povidone-iodine against all forms of Acanthamoeba. IMPORTANCE Understanding the most efficacious products will allow clinicians to best communicate to patients and consumers the safest products on the market to reduce adverse events, including microbial keratitis, during contact lens use.

Concurrent subcutaneous and ocular infections with Dirofilaria repens in a Polish patient: a case report in the light of epidemiological data.

Dirofilariasis is an emerging zoonosis caused by nematodes of the genus Dirofilaria, most often D. repens and D. immitis. The main final hosts and reservoirs of pathogens are dogs. The intermediate hosts and vectors of infection are female mosquitoes (Culicidae). Human is an accidental host in which the parasite does not usually mature. Over the past 20 years, the range of Dirofilaria spp. in Europe has expanded. We present an unusual case of multifocal dirofilariasis of mixed subcutaneous-ocular course caused by D. repens in a 52-year-old Polish patient who was probably infected in Spain or Croatia, where she stayed one year before the onset of symptoms. Surgical removal of the nematodes followed by treatment with Ivermectin in a single dose of 1200 µg and Doxycycline 200 mg daily for 7 days resulted in complete recovery. We believe that all cases of human dirofilariasis, especially in countries where the disease is not frequent at present, should be registered for epidemiological purposes. Moreover, due to the widening of the range of D. repens and D. immitis occurrence and the possibility of atypical courses of infection with both nematodes, diagnostics should include the species identification of the parasite.

Eye fluke effects on Danish freshwater fish: Field and experimental investigations.

Eye flukes in fish are common in freshwater lakes. Fish become infected by the penetration of cercariae released from freshwater snails, and high infection pressures may be associated with mortalities in a Danish lake. Examination of two other freshwater lakes, combined with laboratory study, supported the notion. We investigated 77 freshwater fish from two lakes and the infection level suggested the occurrence of a high cercarial infection pressure in the Danish lakes. Dominant genera were Tylodelphys and Diplostomum covering a range of species identified by PCR and sequencing of the 18S (partial)-ITS1-5.8S-ITS2-28S (partial) of the rDNA. Cercariae of the prevalent species Diplostomum pseudospathaceum were used to infect zebrafish Danio rerio for the elucidation of short-term effects on the fish host. Zebrafish did not display abnormal behaviour when exposed to 200-400 cercariae, but a dosage of 600 and 1,000 cercariae/fish proved lethal. When fish were exposed to sublethal dosages, 19 out of 27 immune genes were significantly regulated and three genes encoding cytokine (IL 4/13B, IL-6 and IL-8) were upregulated at 3 hr post-infection (hpi), whereas others were downregulated especially at a later time point. We suggest that direct massive cercarial penetration of fish surfaces may be detrimental and may represent a threat to fish populations.

How does onchocerciasis-related skin and eye disease in Africa depend on cumulative exposure to infection and mass treatment?

BACKGROUND: Onchocerciasis (river-blindness) in Africa is targeted for elimination through mass drug administration (MDA) with ivermectin. Onchocerciasis may cause various types of skin and eye disease. Predicting the impact of MDA on onchocercal morbidity is useful for future policy development. Here, we introduce a new disease module within the established ONCHOSIM model to predict trends over time in prevalence of onchocercal morbidity. METHODS: We developed novel generic model concepts for development of symptoms due to cumulative exposure to dead microfilariae, accommodating both reversible (acute) and irreversible (chronic) symptoms. The model was calibrated to reproduce pre-control age patterns and associations between prevalences of infection, eye disease, and various types of skin disease as observed in a large set of population-based studies. We then used the new disease module to predict the impact of MDA on morbidity prevalence over a 30-year time frame for various scenarios. RESULTS: ONCHOSIM reproduced observed age-patterns in disease and community-level associations between infection and disease reasonably well. For highly endemic settings with 30 years of annual MDA at 60% coverage, the model predicted a 70% to 89% reduction in prevalence of chronic morbidity. This relative decline was similar with higher MDA coverage and only somewhat higher for settings with lower pre-control endemicity. The decline in prevalence was lowest for mild depigmentation and visual impairment. The prevalence of acute clinical manifestations (severe itch, reactive skin disease) declined by 95% to 100% after 30 years of annual MDA, regardless of pre-control endemicity. CONCLUSION: We present generic model concepts for predicting trends in acute and chronic symptoms due to history of exposure to parasitic worm infections, and apply this to onchocerciasis. Our predictions suggest that onchocercal morbidity, in particular chronic manifestations, will remain a public health concern in many epidemiological settings in Africa, even after 30 years of MDA.

Feline ocular toxoplasmosis: seroprevalence, diagnosis and treatment outcome of 60 clinical cases.

Toxoplasmosis is one of the most important protozoa zoonotic diseases worldwide. The present study describes the clinical, seroprevalence findings with ocular toxoplasmosis and the outcome of medicinal treatment of these cats. This study was carried out on 105 cats with various ocular signs, no historical evidence of ocular trauma or drug/vaccine exposure for at least 3 months prior to admission, and without clinical or laboratory evidence of other systemic diseases. Complete case history, physical and ophthalmic examinations were carried out. The seroprevalence of Toxoplasma gondii antibodies was determined using the Toxoplasma Ab Rapid Test and Enzyme Linked Immunosorbent Assay. Out of 105 examined cats with ocular lesions, 60 cats representing 57.14% were seropositive to T. gondii. Out of these 60 cats, 15 cats (25%) had bilateral ocular abnormalities, 25 cats (41.67%) had right-sided ocular disease, and 20 cats (33.33%) had left-sided ocular disease. There were 38 cats (63.33%) with anterior uveitis, 12 cats (20%) with posterior segment involvement, 5 cats (8.33%) with anterior uveitis and anterior chamber abnormalities, 3 cats (5%) with corneal abnormalities and 2 cats (3.34%) with anterior uveitis with concurrent corneal involvement. There was a significant difference in the index values of IgM and IgG between seropositive and seronegative cats with T. gondii antibodies (p⟨0.05). There was no significant difference between the different ages, genders and breeds of cats with seroprevalence of T. gondii antibodies as well as between the age and total number of cats with seropositive and seronegative T. gondii. Out of 60 treated cats, 28 cats (46.7%), 25 cats (41.7%) and 7 cats (11.6%) showed complete, partial and poor response to treatment, respectively. In conclusion, cats showing ocular signs without obvious etiology should be examined serologically for toxoplasmosis and the seropositive cats should be treated with both specific topical and systemic treatments.

Frequency and visual outcomes of ocular toxoplasmosis in an adult Brazilian population.

Although ocular toxoplasmosis is a leading cause of posterior uveitis worldwide, there is scarce information about the real-life frequency of ocular lesions, visual outcomes, and risk factors for poor prognosis. We conducted a community-based cross-sectional study with 721 adults living in Cássia dos Coqueiros, Southeast Brazil, consisted of visual acuity measurement, dilated ocular examination, a risk-factor questionnaire, and peripheral blood collection for anti-T. gondii serology. Presumed toxoplasmic lesions were recorded on video and analyzed by experienced and masked ophthalmologists. Ocular toxoplasmosis was determined if at least one suspected lesion was appointed by two graders in the presence of positive anti-T. gondii serology. Forty-eight eyes (n = 42 participants; 6.7% among those with positive anti-T. gondii serology) with ocular toxoplasmosis were found. Most lesions were single (n = 28; 58.3%), peripheral (n = 34; 77.1%) and unilateral (85.7% of participants); no active lesions were found. Older age was associated with lesions larger than one-disc diameter (p = 0.047), and lower social stratum (OR: 2.89; CI 1.2-6.97; p = 0.018) was associated with the presence of toxoplasmic lesions. Although there were no differences in visual acuity between participants and eyes with or without ocular lesions (p > 0.05), unilateral blindness associated with ocular toxoplasmosis was identified in a reduced number of individuals.

Molecular characterization of Oxyspirura mansoni and Philophthalmus gralli collected from the eyes of domestic chickens in Bangladesh.

A variety of helminths have been found in domestic chickens in Bangladesh, but little is known about their gene sequences. Here, parasitic nematodes and trematodes were collected from the eyes of domestic chickens and analyzed for their morphological and morphometric characteristics, and characterized molecularly. The helminths were identified as Oxyspirura mansoni and Philophthalmus gralli. The ITS1 and ITS2 sequences of O. mansoni were 532 bp and 306 bp in length, respectively, and showed low identity (50.7-62.7%) with those of O. petrowi and O. conjunctivalis. Furthermore, the O. mansoni CO1 sequences (393 bp) showed five haplotypes (97.5-99.5% similarity) that formed a monophyletic clade. With respect to P. gralli, the ITS1 (452 bp) and ITS2 (736 bp) sequences showed 100% similarity with the reference sequences in GenBank. Both the ND1 and CO1 phylograms showed that P. gralli from Bangladesh, Costa Rica and Peru form a monophyletic clade, distinct from the clades of P. lucipetus and P. lacrymosus. Our data show that, Philophthalmus gralli isolates from Bangladesh, Costa Rica and Peru are genetically close to each other.

Pathophysiology of ocular toxoplasmosis: Facts and open questions.

Infections with the protozoan parasite Toxoplasma gondii are frequent, but one of its main consequences, ocular toxoplasmosis (OT), remains poorly understood. While its clinical description has recently attracted more attention and publications, the underlying pathophysiological mechanisms are only sparsely elucidated, which is partly due to the inherent difficulties to establish relevant animal models. Furthermore, the particularities of the ocular environment explain why the abundant knowledge on systemic toxoplasmosis cannot be just transferred to the ocular situation. However, studies undertaken in mouse models have revealed a central role of interferon gamma (IFNγ) and, more surprisingly, interleukin 17 (IL17), in ocular pathology and parasite control. These studies also show the importance of the genetic background of the infective Toxoplasma strain. Indeed, infections due to exotic strains show a completely different pathophysiology, which translates in a different clinical outcome. These elements should lead to more individualized therapy. Furthermore, the recent advance in understanding the immune response during OT paved the way to new research leads, involving immune pathways poorly studied in this particular setting, such as type I and type III interferons. In any case, deeper knowledge of the mechanisms of this pathology is needed to establish new, more targeted treatment schemes.

Ocular Sparganosis: The First Report of Spirometra ranarum in Thailand.

A 22-year-old Thai man from the Northeast region presented with acute eye swelling, itching, and discharge on his left eye. He was suspected of having gnathostomiasis and treated with albendazole and prednisolone for 3 weeks. Nine months later, he was treated with high-dose oral prednisolone for the preliminary and differential diagnoses with thyroid-associated orbitopathy and lymphoma. He had been administered prednisolone intermittently over a few years. Then he developed a painless movable mass at the left upper eyelid and recurrent pseudotumor oculi was suspected. The surgical removal of the mass was performed. A white pseudosegmented worm revealed a definite diagnosis of ocular sparganosis by a plerocercoid larva. Molecular diagnosis of the causative species was made based on the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Proper technique of extraction and amplification of short fragments DNA from formalin-fixed paraffin-embedded tissue successfully identified parasite species. The result from the sequencing of the PCR-amplified cox1 fragments in this study showed 99.0% sequence homology to Spirometra ranarum. This is the first report of S. ranarum in Thailand.

Several Cases of Ocular Dirofilariasis in Bulgaria.

OBJECTIVES: In this study, we describe ocular dirofilariasis in Bulgaria. MATERIALS AND METHODS: We studied 7 patients with a subconjunctival or periorbital form of Dirofilaria repens infection during 2010-2019. Morphological, serological, and paraclinical diagnostic methods were used. RESULTS: The patients (6 females, 1 male) were aged between 23 and 72 years. In 3 patients, subcutaneous nodules were detected in the area of the upper eyelid, in 1 patient the location was suborbital. In 3 other patients, a subconjunctival location was found. All patients were cured definitively by removal of the larva, without etiologic treatment. CONCLUSION: The most reliable and easily accessible diagnostic method is morphological analysis by microscopy of histological preparations of the parasite. In dirofilariasis, ocular location is the most common in humans, and it deserves special attention of clinicians.

Two Ocular Angiostrongyliasis Cases in Thailand with Molecular Identification of Causative Parasite Species.

Human angiostrongyliasis is an important foodborne helminthic zoonosis caused by the nematodes of the genus Angiostrongylus. We describe two parasitologically confirmed cases of ocular angiostrongyliasis, presenting at a tertiary care hospital in Thailand between 2012 and 2018. Parasites were surgically recovered from patients' eyes and morphologically identified as Angiostrongylus species. DNA analysis allowed identification of Angiostrongylus cantonensis. Polymerase chain reaction was used to amplify all or part of the small nuclear ribosomal subunit, the second internal transcribed spacer region, and cytochrome c oxidase subunit 1. The sequences subsequently obtained were highly similar to those of A. cantonensis (97-100%). This is the first molecular confirmation that A. cantonensis is a causative agent of human angiostrongyliasis in Thailand.

First report of the isolation and phylogenetic characterization of equine Setaria digitata from India based on mitochondrial COI, 12S rDNA, and nuclear ITS2 sequence data.

Equine ocular setariasis arising mainly from ectopic infestation of Setaria digitata is a common vision impairing ophthalmic disease in India, and the identification of this filarial nematode is based solely on morphology. However, morphological characters alone are inadequate to detect and differentiate S. digitata from its congeners. The present communication reports the first phylogenetic characterization of equine S. digitata from India based on sequences derived from the mitochondrial cytochrome c oxidase subunit 1 (COI), the mitochondrial small subunit ribosomal DNA (12S rDNA), and the nuclear internal transcribed spacer 2 (ITS2). Three isolates were characterized for each gene, and respective sequences were submitted to NCBI database (MN078131, MN078132, and MN095798). The sequences were also compared with the other related sequences available from PubMed around the globe, and phylogenetic analysis was carried out in conjunction with nucleotide homologies. There was no intraspecific variation among the Indian isolates. The phylogenetic analysis of S. digitata, inferred from these genes, showed that the isolate sequences obtained from different host species created a separate monophyletic clade within the genus Setaria with minor sequence variations revealing similar molecular characteristics of S. digitata isolates throughout the globe. In addition, the studied Indian isolates were found closer to Sri Lankan isolates. The S. digitata and S. labiatopapillosa appeared as sister species.

Risky business: influence of eye flukes on use of risky microhabitats and conspicuousness of a fish host.

A prerequisite for a parasitic manipulation to be considered adaptive is that it confers a fitness benefit to the parasite, such as increased transmission to another host. These manipulations can involve alterations to a wide range of host phenotypic traits, including microhabitat choice. Eye flukes of the trematode family Diplostomidae use fish as intermediate hosts and must be transmitted by predation to a piscivorous bird. In New Zealand, the diplostomid Tylodelphys darbyi infects the eyes of a widespread endemic freshwater fish, the common bully Gobiomorphus cotidianus. Within the eye, T. darbyi metacercariae achieve large sizes and move freely about the aqueous and vitreous humors of the eye. We hypothesized that higher intensities of T. darbyi would (i) cause bullies to show increased activity and spend more time moving about in open space (i.e., more conspicuous, risky microhabitat) and (ii) reduce their ability to compete for shelter with fish harboring lower infection levels. Our experiments showed that heavily infected fish were more active and spent more time in the open, although the effect was age-dependent, with immature fish displaying decreases in activity and time spent in the open with increasing intensities of infection. We also demonstrated that heavily infected female bullies have a lower probability of using shelter, but males show the opposite pattern. It is possible that using more risky microhabitats increases the likelihood of the fish being eaten by the parasite's predatory avian definitive hosts. However, our findings indicate that age- and sex-dependent effects call for a more nuanced interpretation.

First report of eyeworm infection by Thelazia callipaeda in gray wolf (Canis lupus) from Serbia.

Thelazia callipaeda, originally known as an "Oriental eyeworm," is a small nematode parasitizing the conjunctival sacs of domestic and wild animals and humans. Previous studies conducted in Serbia have reported the eyeworm infections in dogs, cats, and foxes, as well as in a human patient. As the data regarding thelaziosis from wildlife is still scarce, the aim of this study was to investigate the presence of T. callipaeda in gray wolf (Canis lupus) from Serbia. All collected nematodes were morphologically identified as T. callipaeda males (n = 64) or females (n = 225). Molecular characterization, conducted by PCR amplification followed by sequence analysis of partial cytochrome c oxidase subunit 1 gene (cox1), revealed only haplotype 1 of T. callipaeda. The overall prevalence of thelaziosis was 38.1% (8/21). In all positive animals, both eyes were affected, with a total parasitic load ranging from four to 132 worms per animal. Our results indicate the important epidemiological role of wolves as wildlife reservoirs of T. callipaeda, expanding geographic range of infection, as well as intra- and interspecies contact rates, although the role of other wild carnivore species (i.e., foxes and jackals) should be investigated in future studies.