Serologic Detection of <i>Toxoplasma gondii</i>in Cat Owners Residing at Dhaka Metropolitan Area of Bangladesh

Toxoplasma gondii is a zoonotic protozoan that can infect any warm-blooded mammal. T. gondii infects about one-third of the human population on the planet. Infection with the parasite in human causes toxoplasmosis that may pose a high risk in immunocompromised individuals under certain clinical conditions. Cats are the ultimate hosts of T. gondii where oocysts are formed through mating of male and female gametes. Infected cats can expel T. gondii oocysts in their feces, and thereby capable of pass on a disease to humans and other animals through consumption of foods, vegetables and water that are polluted with cat feces. The study was conducted to detect the presence of anti-T. gondii IgM and IgG antibodies in the blood of individuals with or without cat contact to determine if there is any relationship between cat contacts and T. gondii infection in humans. To address this, we enrolled subjects who contacted with the cat as target group and individuals with no cat contact as control group. Following register of different demographic data (including age, sex, education, foods habit, income status, etc.), whole blood from each enrolled subject of both the target group and control group was collected for serum preparation. T. gondii infected subjects were detected by Toxo Rapid test kit through identifying anti-T. gondii IgM and IgG antibodies in their serum. We found that only three out of twenty subjects who were in contact with cat showed positive IgG response while IgM antibody response was absent for all subjects. When compared with the data from control group, we did not find any significant association (p = 0.33) of cat contact with the transmission of T. gondii into human. However, with this small number of study subjects, we cannot conclusively say that there is no impact of cat contact on the transmission of T. gondii into human. Whether any association exists or not can be ascertained with a large number of subjects from different areas of Bangladesh in a future study in the population.

Microbe—Chloroacetanilide Herbicide Interaction across Soil Type

An investigation was carried out under laboratory conditions to study the persistence of butachlor applied at recommended dose (2 kg ai/ha) along with its impact on microbial activity as well as growth of colonial bacteria and fungi in alluvial (Typic Haplaquent), lateritic (Typic Haplustalf) and coastal (Typic Haplaquept) soils. Butachlor caused a significant increment in microbial activity following an initial diminution in between 10 to 22 days of incubation depending on the type of soil. The herbicide resulted in a significant shrinkage in bacterial community during later stages of incubation in lateritic and coastal soils in spite of a significant swelling on the 15th day in lateritic and alluvial soils. Fungal community significantly expanded at the initial stage in lateritic soil and during later stages in alluvial soil by the application of butachlor but shriveled during later stages in the lateritic soil, intermediate stage in coastal soil and initial stages in alluvial soil. Alluvial soil reared the highest population of colonial bacteria and exhibited highest microbial activity while coastal soil significantly pressed them down to the lowest. However, lateritic soil was the best niche for fungal community. Co-metabolism was the main phenomenon in butachlor metabolism particularly in coastal soil, though zymogenous microbes including bacteria and fungi also participated in both lateritic and alluvial soil at certain stages. The persistence of butachlor was the lowest in alluvial soil followed by lateritic and coastal soil, respectively. Among the soil types application of butachlor is safe in alluvial soil.