Background/objective Given the economic importance of camels and the threats posed by zoonotic diseases, this study aimed to investigate the seroprevalence of Toxoplasma gondii (T. gondii) infection in camel herds in Sistan and Baluchestan Province, Iran. Methods Using enzyme-linked immunosorbent assay (ELISA), this cross-sectional study collected serum samples from 184 camels and tested them for anti-Toxoplasma IgG antibodies between January 2021 and September 2022 from camel herds in Sistan-va-Baluchestan province. Moreover, risk factors associated with infection, including age, sex, geographic location, season, and environmental factors, were evaluated. Additionally, databases such as Google Scholar, PubMed, Scopus, and Embase were examined without considering the year. Search keywords included camel, Camelus dromedarius, Toxoplasma, Toxoplasma infection, toxoplasmosis, prevalence, country names, and diagnosis, which were searched in combination. Results The results showed an overall seroprevalence of T. gondii infection of 11.95% (22/184) among the camels in the study area. Although a higher prevalence was observed in males (13%) compared to females (10.7%), this difference was not statistically significant (p = 0.634). Furthermore, no significant association was found between T. gondii infection and a history of abortion, the presence of domestic cats, or rodents (p > 0.05). A worldwide review has found that various diagnostic methods have been employed in these studies to diagnose Toxoplasma infection. It has been found that molecular methods, such as PCR, have been able to identify more cases in recent years due to their high level of accuracy. Conclusion Based on the results, T. gondii infection is present in camels worldwide, and preventive measures and public health warnings should be implemented.
Fish-borne zoonotic trematodes remain important food-borne parasitic infections in East and Southeast Asia, where transmission depends on snail intermediate hosts in freshwater ecosystems. Surveillance of cercarial infections in freshwater snails is therefore essential for understanding local transmission dynamics and epidemiological risk. This study investigated cercarial infections in thiarid snails from southern Thailand, with emphasis on zoonotic heterophyids and transmission ecology. A total of 566 thiarid snails were examined, of which Melanoides tuberculata was the dominant species ( n = 476). Cercarial infections were detected exclusively in M. tuberculata (10/476; 2.1%). Three trematode species were identified: parapleurolophocercous cercariae of Heterophyes heterophyes and Haplorchis pumilio, and virgulate xiphidiocercariae of Loxogenes liberum. Species identification was achieved through integrated morphological examination and Internal transcript spacer 2 (ITS2) sequence analysis, which confirmed all three taxa. H. heterophyes and H. pumilio each infected a different individual snail (0.2%), with no co-infections observed, whereas L. liberum was detected in eight snails (1.7%). This study represents the first molecularly confirmed record of H. heterophyes from the freshwater thiarid snail M. tuberculata in Thailand. The findings expand the known ecological host range of this medically important heterophyid beyond its traditionally recognized brackish-water transmission system and suggest that freshwater transmission pathways may occur under suitable environmental conditions. The study further demonstrates the value of combining morphology with molecular tools for accurate identification of cercariae and highlights the importance of continued surveillance of snail-borne trematodes in endemic freshwater ecosystems.
Cockroaches are known vectors of various pathogens due to their unsanitary feeding habits and close association with human habitats. The COVID-19 pandemic has raised concerns about potential non-human transmission routes, including mechanical transmission by insects. This study investigates whether cockroaches can carry SARS-CoV-2 RNA and their potential role in mechanical transmission in Shiraz, Iran. Using real-time RT-PCR (positivity threshold: Ct < 38.0 for both RdRp and N genes), we molecularly examined 200 cockroaches (100 Blattella germanica and 100 Periplaneta americana) randomly selected from a total of 400 collected specimens. An additional 200 specimens were allocated to insectarium-based vertical transmission experiments. SARS-CoV-2 RNA was detected on external surfaces of 59/200 specimens (29.5%; 95% CI: 23.4–36.3%), with significantly higher detection in P. americana from hospital sewage (35/50, 70%; 95% CI: 55.9–81.2%) than B. germanica from dormitory kitchens (24/50, 48%; 95% CI: 34.2–62.2%; χ2 = 5.01, p = 0.025). Internal viral RNA was detected in only 11/200 specimens (5.5%; 95% CI: 3.1–9.6%), with significantly lower loads than surface samples (mean surface-to-internal ratio: 15.2:1; p < 0.001). No viral RNA was detected in 200 nymphs or 50 egg capsules from insectarium-reared populations, indicating no evidence of transovarial transmission under experimental conditions. These findings demonstrate that cockroaches can carry SARS-CoV-2 RNA on their external surfaces, suggesting potential for mechanical carriage rather than biological transmission. However, as RT-PCR detects nucleic acids rather than infectious virus, our results do not establish mechanical transmission. Further research incorporating viral viability assays is needed to determine whether cockroaches can transmit infectious SARS-CoV-2 and contribute to COVID-19 epidemiology.
Strongyloidiasis remains endemic in parts of Japan, particularly Okinawa Prefecture, and can progress to disseminated disease with high mortality; however, nationwide data on hospitalized patients, including regional differences and the impact of disseminated disease, are limited. We conducted a retrospective nationwide study using the Diagnosis Procedure Combination database to identify hospitalized patients with strongyloidiasis in Japan between fiscal years 2014 and 2020, using ICD-10 code B78, with disseminated cases defined as B78.7. Demographic characteristics, geographic distribution, and outcomes were analyzed, with a focus on disseminated disease and regional differences between Okinawa and other areas. After excluding duplicate cases, 252 hospitalized patients were included (mean age, 77.6 years; male-to-female ratio, 1.47). Most patients were from the Kyushu and Okinawa regions, with Okinawa accounting for 82.1% of cases. Disseminated strongyloidiasis was identified in 44 patients (17.5%) and was associated with poorer neurological status at admission and higher in-hospital mortality; 11 patients with disseminated disease died during hospitalization (25.0%). Severe complications, including sepsis (54.5%) and meningitis (25.0%), were frequently observed in disseminated cases. Patients hospitalized outside Okinawa were younger than those hospitalized in Okinawa, whereas the proportions of disseminated disease and in-hospital mortality did not differ significantly between regions. In Japan, hospitalized patients diagnosed with strongyloidiasis were predominantly concentrated in Okinawa; however, severe cases also occurred in other regions. These findings highlight the importance of considering strongyloidiasis in patients with relevant epidemiological backgrounds, particularly in the setting of immunosuppression, regardless of their current geographic location.
