The use of sulfadoxine and pyrimethamine (SP) for treatment of vivax malaria is uncommon in most malarious areas, but Plasmodium vivax isolates are exposed to SP because of mixed infections with other Plasmodium species. As P. vivax is the most prevalent species of human malaria parasites in Iran, monitoring of resistance of the parasite against the drug is necessary. In the present study, 50 blood samples of symptomatic patients were collected from 4 separated geographical regions of south-east Iran. Point mutations at residues 57, 58, 61, and 117 were detected by the PCR-RFLP method. Polymorphism at positions 58R, 117N, and 117T of P. vivax dihydrofolate reductase (Pvdhfr) gene has been found in 12%, 34%, and 2% of isolates, respectively. Mutation at residues F57 and T61 was not detected. Five distinct haplotypes of the Pvdhfr gene were demonstrated. The 2 most prevalent haplotypes were F57S58T61S117 (62%) and F57S58T61N117 (24%). Haplotypes with 3 and 4 point mutations were not found. The present study suggested that P. vivax in Iran is under the pressure of SP and the sensitivity level of the parasite to SP is diminishing and this fact must be considered in development of malaria control programs.
Amino Acid Substitution/genetics ; Antimalarials/*pharmacology ; Drug Combinations ; *Drug Resistance ; Haplotypes ; Humans ; Iran ; Malaria, Vivax/*parasitology ; *Mutation, Missense ; Plasmodium vivax/*enzymology/genetics/isolation & purification ; Polymorphism, Genetic ; Pyrimethamine/*pharmacology ; Sulfadoxine/*pharmacology ; Tetrahydrofolate Dehydrogenase/*genetics

Objective: To identify serodiagnosis and quantification of Toxoplasma gondii (T. gondii) infection among pregnant women in Salmas, northwest of Iran. Methods: In this cross-sectional study, 276 blood samples were collected from pregnant women referred to the health care centers in Salmas city. The demographic variables were also recorded. Titers of anti-Toxoplasma IgM and IgG antibodies (Ab) were determined using the chemiluminescence immunoassay. Quantitative real-time PCR targeting the T. gondii repeated element gene was also performed on the blood sample. Results: Out of all, 19.92% (55/276) and 2.17% (6/276) patients were seropositive for anti-Toxoplasma IgG and IgM Ab, respectively. Moreover, the presence of T. gondii DNA was observed in 12.31% (34/276) blood samples. A significant relationship was observed between the IgG Ab seropositivity and contact with the cat as a risk factor (P=0.022). Conclusions: The seroprevalence rate of T. gondii infection in pregnant women is relatively low. Consequently, the seronegative pregnant women are at risk, and a considerable rate of positive blood samples for the presence of parasite's DNA should not be ignored. Besides, quantitative real-time PCR could be considered as an accurate method for diagnosis of acute toxoplasmosis especially when the precise results are of the most importance in pregnancy. Limiting contact with cats is also suggested for pregnant women.