Factors Affecting Primaquine Combination Treatment in Malaria Patients in Selangor, Malaysia.

INTRODUCTION: Primaquine is vital for the management of liver-stage Plasmodium vivax and Plasmodium ovale malaria. However, primaquine effectiveness is dependent on various factors and differs between populations. Therefore, this study was conducted to identify factors that affect the length of stay and relapse during primaquine combination treatment in malaria-infected patients in the local setting. MATERIALS AND METHODS: A retrospective study on the use of primaquine combination among P. vivax and P. ovale infected patients in Selangor, Malaysia within a 5-year period from 2011 to 2015 was obtained from the National Malaria Case Registry, Malaysia. Data collected were patient characteristics (age, gender, nationality, glucose-6-phosphate dehydrogenase, pregnancy); disease characteristics (survival, past malaria infection, parasite type, presence of gametocyte, parasite count, week onset, severity, transmission type); and treatment characteristics (type of antimalarial, treatment completion). Outcome measures were length of stay and relapse during a 1-year follow-up. RESULTS: A total of 635 patients were included in the study. Based on a multivariate logistic regression analysis, the significant predictors for length of stay were gender (P = 0.009) and indigenous transmission (P < 0.001). Male patients had a shorter length of stay than females by 0.868 days (P = 0.009), and indigenous transmission took 1.82 days more compared to nonindigenous transmission (P < 0.001). Predictors for relapse were indigenous transmission of malaria (P = 0.019), which was 15.83 times more likely to relapse than nonindigenous transmission (P < 0.01). CONCLUSIONS: This study reveals that the effectiveness of primaquine was clinically associated with gender and indigenous transmission. To that end, vigilant monitoring of primaquine use is required to reduce relapse and future transmission.

An endemic focus of visceral leishmaniasis in Meshkin-Shahr, east Azerbaijan province, north-west part of Iran and IFA serological survey of the disease in this area.

The incidence of visceral leishmaniasis has being increased in Iran during the recent decade. Since 1980, more than 200 cases have been diagnosed from East Azerbaijan province, mostly, from Meshkin-Shahr area. It seems, that kala-azar has being endemic in this area for a long time. The majority (86%) of kala-azar cases were found among children up to 4 years. The sex incidence ratio of males/females was 1.27/1. In IFA serological survey, sero-positive rate in females was higher than males. However, geometric mean of leishmanial antibody titers in males was, slightly, more than females. These serological findings indicate that females are exposed to the infection at least as much as males. The cross-sectional IFA serological survey, relatively reflected the kala-azar status among different studied groups with various incidences of the disease in Meshkin-Shahr area. IFAT showed also a good efficiency in the assessment of the treatment in the treated kala-azar patients.

Application of an enzyme-linked immunosorbent assay (ELISA) for determination of the human blood index in anopheline mosquitoes collected in Iran.

The microplate method of an ELISA was modified for identification of human blood meals from 5,325 engorged mosquitoes belonging to 12 species of Anopheles captured in 19 provinces of Iran. Four hundred and four (7.5%) specimens reacted with the ELISA anti-human alkaline phosphatase conjugate. The human blood index in nine species of Anopheles varied from 3.6 to 23.7%. The results of this field application of the ELISA indicated that the technique is practical, reproducible and generally a suitable serological test for determination of human blood index of the anopheline mosquitoes.

Animal toxoplasmosis in Iran.

A latex agglutination slide test for Toxoplasma antibodies was used on serum samples collected from various animals (111 cats, 113 dogs, three jackals, 393 sheep, 272 goats, 69 cows) in different parts of Iran. The sero-positive rate in titres 1:2-1:256 in different animals ranged from 12.6 to 56.0%; the highest (56.0%) was found in the stray dogs. Suspensions of the brains of 120 sero-positive animals (17 cats, 14 dogs, one jackal, 66 sheep, 22 goats) as well as 13 sero-negative animals (11 dogs, two jackals) and four black kites (Milvus migrans) not serologically tested were inoculated intraperitoneally into mice for isolation of Toxoplasma gondii. Altogether 16 strains of T. gondii were isolated from cats (47.0%) dogs (14.2%), sheep (7.5%) and a bird (black kite).

Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG seems to be dependent upon T-cells in Toxoplasma-infected mice.

Effect of cyclophosphamide on Toxoplasma gondii infection: reversal of the effect by passive immunization.

Treatment of mice with cyclophosphamide (CY) at a dose of 250 mg/kg body weight 24 hr prior to infection with an avirulent strain of Toxoplasma gondii delays the appearance of antibody by about one week and results in 70% mortality. To discount other effects of CY besides inhibition of antibody synthesis, CY-treated infected mice were passively immunized with a pooled specific serum collected from chronically infected syngeneic animals. Passive immunization reversed the effect of CY treatment if the titre of antibody in recipients reached 1 : 512 or more, as measured by the indirect immunofluorescence technique (IFT). It is therefore suggested that antibody plays an important role in establishing an infection-immunity (premunition) in this system.