Summary: Neuro‐immune interactions, particularly those driven by neuropeptides, are increasingly implicated in immune responses. For instance, triggering calcium‐channel transient receptor potential vanilloid 1 (TRPV1) on sensory nerves induces the release of calcitonin‐gene‐related peptide (CGRP), a neuropeptide known to moderate dendritic cell activation and T helper cell type 1 polarization. Despite observations that CGRP is not confined to the nervous system, few studies have addressed the possibility that immune cells can respond to well‐documented ‘neural’ ligands independently of peripheral nerves. Here we have identified functionally relevant TRPV1 on primary antigen‐presenting cells of the spleen and have demonstrated both calcium influx and CGRP release in three separate strains of mice using natural agonists. Furthermore, we have shown down‐regulation of activation markers CD80/86 on dendritic cells, and up‐regulation of interleukin‐6 and interleukin‐10 in response to CGRP treatment. We suggest that dendritic cell responses to neural ligands can amplify neuropeptide release, but more importantly that variability in CGRP release across individuals may have important implications for immune cell homeostasis.

Megaselia scalaris (Diptera: Phoridae) is one of the medically important insects. Maggots from a urine sample of a 5-year-old Saudi girl were examined microscopically for identification. These maggots were cultured to become adult flies. Larvae and adults were identified using standard keys. Protozoan flagellates were obtained from the gut of the larvae. This is the first report of M. scalaris as a causative agent of urinary human myiasis in Saudi Arabia.

(1) Background: Toxoplasma gondii (T. gondii) is one of the most prevalent parasites to affect humans and animals; (2) Methods: From January to December 2020, using a commercial enzyme-linked immunosorbent assay (ELISA) kit, a cross-sectional study was conducted to establish the seroprevalence of T. gondii in 390 dromedary camels raised in three governorates in Egypt and to identify the potential risk factors associated with infection; (3) Results: Overall, T. gondii seroprevalence in camels was 46.9%. Moreover, locality, sex, age, contact with small ruminants, history of abortion, and number of parities were found as risk factors for T. gondii infection in univariable analysis. The seropositivity to T. gondii increased significantly in camels living in Marsa Matrouh (OR = 2.02), among camels of more than 8 years old (OR = 5.28). Additionally, the likelihood of acquiring T. gondii infection was increased in camels that had contact with small ruminants (OR = 3.85) and a history of abortion (OR = 3.84) with these having parity more than four times (OR = 17.72); (4) Conclusions: The evaluation of seroprevalence and related risk factors for T. gondii infection is crucial for implementing an effective control programme to minimise and control T. gondii infection in camels and, as a result, transmission to humans.

Background: Although, approximately 30% of the world’s population is estimated to be infected with Toxoplasma gondii (T. gondii) with serious manifestations in immunocompromised patients and pregnant females, the available treatment options for toxoplasmosis are limited with serious side effects. Therefore, it is of great importance to identify novel potent, well tolerated candidates for treatment of toxoplasmosis. The present study aimed to evaluate the effect of Zinc oxide nanoparticles (ZnO NPs) synthesized using Zingiber officinale against acute toxoplasmosis in experimentally infected mice. Methods: The ethanolic extract of ginger was used to prepare ZnO NPs. The produced ZnO NPs were characterized in terms of structure and morphology using Fourier Transformed Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), UV- spectroscopy and scanning electron microscopy (SEM). The prepared formula was used in treatment of T. gondii RH virulent strain. Forty animals were divided into four groups, with ten mice per group. The first group was the uninfected, control group. The second group was infected but untreated. The third and the fourth groups received ZnO NPs and Spiramycin orally in a dose of 10 mg/kg and 200 mg/kg/day respectively. The effect of the used formulas on the animals survival rate, parasite burden, liver enzymes -including Alanine transaminase (ALT) and aspartate transaminase (AST)-, nitric oxide (NO) and Catalase antioxidant enzyme (CAT) activity was measured. Moreover, the effect of treatment on histopathological alterations associated with toxoplasmosis was examined. Results: Mice treated with ZnO NPs showed the longest survival time with significant reduction in the parasite load in the livers and peritoneal fluids of the same group. Moreover, ZnO NPs treatment was associated with a significant reduction in the level of liver enzymes (ALT, AST) and NO and a significant increase in the antioxidant activity of CAT enzyme. SEM examination of tachyzoites from the peritoneal fluid showed marked distortion of T. gondii tachyzoites isolated from mice treated with ZnO NPs in comparison to untreated group. T. gondii induced histopathological alterations in the liver and brain were reversed by ZnO NPs treatment with restoration of normal tissue morphology. Conclusion: The produced formula showed a good therapeutic potential in treatment of murine toxoplasmosis as demonstrated by prolonged survival rate, reduced parasite burden, improved T. gondii associated liver injury and histopathological alterations. Thus, we assume that the protective effect observed in the current research is attributed to the antioxidant capability of NPs. Based on the results obtained from the current work, we suggest greenly produced ZnO NPs as a chemotherapeutic agent with good therapeutic potential and high levels of safety in the treatment of toxoplasmosis.

Background: Livelihood activities and human movements participate in the epidemiology of vector-borne diseases and influence malaria risk in elimination settings. In Saudi Arabia, where malaria transmission intensity varies geographically, it is vital to understand the components driving transmission within specific areas. In addition, shared social, behavioural, and occupational characteristics within communities may provoke the risk of malaria infection. This study aims to understand the relationship between human mobility, livelihood activities, and the risk of malaria infection in the border region of Jazan to facilitate further strategic malaria interventions. In addition, the study will complement and reinforce the existing efforts to eliminate malaria on the Saudi and Yemen border by providing a deeper understanding of human movement and livelihood activities. Methods: An unmatched case–control study was conducted. A total of 261 participants were recruited for the study, including 81 cases of confirmed malaria through rapid diagnostic tests (RDTs) and microscopy and 180 controls in the Baish Governorate in Jazan Provinces, Saudi Arabia. Individuals who received malaria tests were interviewed regarding their livelihood activities and recent movement (travel history). A questionnaire was administered, and the data was captured electronically. STATA software version 16 was used to analyse the data. Bivariate and multivariate analyses were conducted to determine if engaging in agricultural activities such as farming and animal husbandry, recent travel history outside of the home village within the last 30 days and participating in spiritual gatherings were related to malaria infection status. Results: A logistical regression model was used to investigate components associated with malaria infection. After adjusting several confounding factors, individuals who reported travelling away from their home village in the last 30 days OR 11.5 (95% CI 4.43–29.9), and those who attended a seasonal night spiritual gathering OR 3.04 (95% CI 1.10–8.42), involved in animal husbandry OR 2.52 (95% CI 1.10–5.82), and identified as male OR 4.57 (95% CI 1.43–14.7), were more likely to test positive for malaria infection. Conclusion: Human movement and livelihood activities, especially at nighttime, should be considered malaria risk factors in malaria elimination settings, mainly when the targeted area is limited to a confined borderland area.