Risk of mother-to-child transmission of Toxoplasma gondii (T. gondii) during pregnancy is much greater in women who are exposed to primary T. gondii infection (toxoplasmosis) after conception compared to those who exposed to the infection before conception. Therefore, laboratory tests that help classify recent primary toxoplasmosis are important tools for the management of pregnant women suspected to T. gondii exposure. Detection of Toxoplasma IgM (Toxo IgM) is a sensitive indicator of primary toxoplasmosis, but the indicator specificity is low because sometimes natural IgM antibodies react with Toxoplasma antigens in absence of the infection. Furthermore, Toxo IgM sometimes persists in blood serum for several months or years following the primary infection. In recent decades, Toxo IgG avidity assay has been used as a standard diagnostic technique for a better estimation of the infection acquisition time and identification of the primary T. gondii infection during pregnancy. Avidity is described as the aggregate strength; by which, a mixture of polyclonal IgG molecules react with multiple epitopes of the proteins. This parameter matures gradually within six months of the primary infection. A high Toxo IgG avidity index allows a recent infection (less than four months) to be excluded, whereas a low Toxo IgG avidity index indicates a probable recent infection with no exclusions of the older infections. The current mini review is based on various aspects of T. gondii IgG avidity testing, including a) description of avidity and basic methods used in primary studies on T. gondii IgG avidity and primary infections; b) importance of IgG avidity test in pregnancy; c) result summary of the major studies on use of T. gondii IgG avidity assay in pregnancy; d) brief explanation of the T. gondii IgG avidity values in newborns; e) result summary of the major studies on T. gondii IgG avidity and polymerase chain reaction (PCR); f) discussion of commercially available T. gondii IgG avidity assays, including newer automated assays; and g) current issues and controversies in diagnosis of primary T. gondii infections in pregnancy.

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Background: Besides the considerable role of blackflies to the transmission of many disease agents, these flies considered as annoying biting pests of wildlife, livestock, poultry, and humans. There are few literature reports of blackfly fever following Simulium spp. This study describes a case of blackfly fever and dermatitis following blackflies numerous bites in Iran. Case presentation: The present report describes a 25-year-old man that was attacked by numerous flies while fishing and camping near Namrood river in Firuzkuh County, Tehran Province, Iran. Pruritic dermatitis with marked edema appeared mainly on the hands and legs and subsequently, the patient's condition worsened with swollen lymph nodes, joints aching, and 40°C fever. The patient's clinical signs and symptoms were alleviated by injection of intramuscular Dexamethasone Phosphate (DEXADIC®) 8 mg/2 ml after 24 h. Conclusions: This study reported a human case with blackfly fever and dermatitis following numerous bites of Simulium kiritshenkoi, for the first time in Iran.

To improve serodiagnostic methods for diagnosis of acute from chronic toxoplasmosis, an economical in-house ELISA for measuring Toxoplasma -specific IgG, IgM and IgG avidity has been developed and assessed based on use of various T. gondii antigens, including SAG1, GRA7 and a combination of SAG1 and GRA7 (SAG1+GRA7) as well as Toxoplasma lysate antigens (TLAs). Performances of in-house IgM, IgG and IgG avidity assays were compared to those of ELISA commercial kits and VIDAS Toxo IgG avidity. A set of 138 sera from patients with acquired T. gondii infection and seronegative people were assessed. Receiver operating characteristic (ROC) analysis revealed an area under curve (AUC) of 0.98, 0.97, 0.99 and 0.99 for IgM-TLAs, IgM-SAG1, IgM-GRA7, and IgM-SAG1+GRA7, respectively. Furthermore, AUC was calculated as 0.99, 0.99, 0.98 and 0.99 for IgG-TLAs, IgG-SAG1, IgG-GRA7 and IgG-SAG1+GRA7, respectively. The current study showed that GRA7 included 100% sensitivity for the detection of Toxo IgM, while SAG1 included 89.7% sensitivity. Furthermore, the highest specificity (97.2%) to detect Toxo IgM was achieved using SAG1+GRA7 antigen. For the detection of Toxo IgG, the highest sensitivity (100%) was recorded for SAG1+GRA7 followed by TLAs (97.9%). The SAG1+GRA7 showed the greatest potential for assessing avidity of IgG antibodies with 97.1% of sensitivity and 96.6% of specificity, compared to VIDAS Toxo IgG avidity. The preliminary results have promised better discriminations between acute and chronic infections using a combination of SAG1 and GRA7 recombinant antigens, compared to TLAs.

Background: Toxocariasis is one of the neglected zoonosis with considerable public health importance around the world. The current study aimed to elucidate the overall prevalence of Toxocara infection in human and definitive hosts and also the contamination of soil and raw vegetables with the ova of these parasites, in Iran, using systematic review and meta-analysis. Methods: Six English and Persian databases were explored from 2000 to 2017 using the terms toxocariasis, Toxocara spp., visceral larva migrans, Iran, epidemiology, and prevalence. This meta-analysis conducted using STATA, and for all statistical tests, a p value less than 0.05 was considered significant. The random-effects model was used to the report of the pooled prevalence with a 95% confidence interval (CI). Results: The pooled prevalence of toxocariasis in human was calculated as 11% (95% CI 8-13%). In terms of definitive hosts, the pooled prevalence of Toxocara infection in dogs and cats were calculated as 17% (95% CI 14-20%) and 37% (95% CI 26-48%), respectively. Also, the pooled prevalence of Toxocara spp. eggs in the soil and raw vegetable samples were calculated as 18% (95% CI 13-23%) and 2% (95% CI 1-3%), respectively. Conclusions: The results of current study demonstrate that toxocariasis should be taken more seriously by health authorities. Implementing an appropriate control program is necessary to reduce the incidence of this disease in Iran.