Toxoplasma Gondii Infection in HIV/AIDS: Prevalence and Risk Factors

BACKGROUND: Toxoplasmosis is an infection caused by the protozoan Toxoplasma gondii. It is common in severely immunecompromisedpersons.OBJECTIVE: To determine the seroprevalence of T. gondii infection and the risk factors associated with the infection and to investigate the association between T. gondii infection and CD4 cell count.METHODS: Sera collected from 242 HIV positive HAART- naive patients were tested for T. gondii specific immunoglobulin G antibodies. Information was obtained using a structured questionnaire. Baseline CD4 cell counts were obtained from patients case files. Data was managed using SPSS version 20 software and Microsoft Excel worksheet.RESULTS: One hundred and sixty eight (69.4%) subjects were females while 74(30.6%) were males. One hundred (41.3%) of study participants were Toxoplasma IgG antibody positive. Thirty two(32) HIV positive pregnant women were among this group studied with 12( 37.5%) being Toxo IgG antibody positive. Toxoplasma seropositivity was higher in females (42.8%) than in males (39.2%), P= 0.60. CD4 cell count level of < 200 was negatively associated with Toxoplasma seropositivity than CD4 count . 200 by logistic regression (OR= 0.6; 95% CI 0.3- 1.0). Living in proximity with cat was positively associated with T. gondii infection (P= 0.01).CONCLUSION: T. gondii infection is common in pregnant women indicating greater probability of congenital transmission of T. gondii. This could form a basis for recommending intensifying health education and prophylactic treatment for all HIV positive pregnant women. Measures should be taken to prevent stray cats from entering homes.Keywords: Toxoplasma gondii , IgG, Seroprevalence, HIV positive, CD4 cells

Evidence of carbamate resistance in urban populations of <it>Anopheles gambiae s.s.</it> mosquitoes resistant to DDT and deltamethrin insecticides in Lagos, South-Western Nigeria

<p>Abstract</p> <p>Background</p> <p>Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of <it>Anopheles gambiae</it> to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin.</p> <p>Methods</p> <p>Two – three day old adult female <it>Anopheles</it> mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the <it>Anopheles gambiae</it> population to bendiocarb insecticide. Members of the <it>A. gambiae complex</it>, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO) synergist assays. The presence of kdr-<it>w/e</it> and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR.</p> <p>Results</p> <p>Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05) but was significantly higher (P < 0.05) in populations exposed to DDT. All mosquitoes tested were identified as <it>A. gambiae s.s</it> (M form). The <it>kdr -w</it> point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. <it>Ace-1R</it> point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted.</p> <p>Conclusion</p> <p>Evidence of carbamate resistance in <it>A. gambiae</it> populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of insecticide resistance management strategies to combat the multiple resistance identified.</p