toxoplasmosis is a zoonotic parasitic disease prevalent all over the world and its causal agent is an intracellular protozoon called toxoplasma gondii . the protozoa was first discovered by nicolle and manceaux ( 1908 ) as ctenodactylus gundi and later named as t. gondii ( 1909 ) ( 1 ) . up to one third of the world s population most infections among humans occur by eating undercooked or raw meat containing tissue cysts or by exposure to oocysts through ingestion of contaminated foods and drinks with cat faeces ( 3 ) . it is also transmitted transplacentally ( 4 ) . in the vast majority of immunocompetent human host , t. gondii ensue a latent infection characterized by the persistence of the organism primarily in brain , skeletal muscle , and heart tissues without causing clinical symptoms ( 5 ) . however , in chronically infected individuals with impaired cell - mediated immunity symptomatic disease more likely occurs as a result of reactivation of latent infection ( 6 , 7 ) . in this group of immunodeficient people , toxoplasmosis causes a large range of manifestations such as , fever , lympaphadenitis and fatal encephalitis ( 8) . moreover , toxoplasmosis has a great public health importance in pregnant women as it can lead to transplacental transmission and involvement of the fetus with pathological effects which even results in uterine death ( 9 , 10 ) . when hiv infected pregnant women are exposed to t. gondii its severity will be doubled both in woman and the fetus ( 9 , 10 ) . accordingly screening of pregnant women for t. gondii infection has been practiced in developed nations . however , serological screening of pregnant women for t. gondii antibodies is not part of routine clinical practices in sub saharan countries including ethiopia , in spite of high prevalence of the infection in this country ( 8 , 11 - 16 ) . data on seroprevalence of t. gondii during pregnancy with hiv co - infection is lacking . this study aimed to determine the magnitude of anti- t. gondii antibody reactivity and associated risk factors of toxoplasmosis among hiv positive and hiv negative pregnant women in northwest of ethiopia . this cross sectional study was conducted among consecutive pregnant women attending antenatal clinic ( anc ) from may 2010 to october 2011 at the gondar university teaching hospital , northwest ethiopia . structured , pre - tested questionnaire was used to collect socio - demographic characteristics and risk factors associated with t. gondii infection . five milliliter ( ml ) of blood was collected from each pregnant woman and serum was separated . sera were tested in duplicate for anti - toxoplasma antibody using the rapid latex agglutination test kit ( biochcek , inc , ca , spain ) following manufacturer s instructions . positive and negative control tests were done for each batch of test run to ensure kits are working properly and technical procedures are carried out correctly . the serum was also tested for the presence of hiv-1/2 antibodies using rapid hiv diagnostic kit following manufacturer s instructions . results were interpreted following the current algorithm of ethiopia adopted from who for screening of hiv-1/2 antibodies . briefly , the sera were tested using khb hiv-1/2 ( shangai kehua bio - engineering co - ltd , shangai , china ) , when the sera were non - reactive it was reported as negative . when the serum was reactive , it was tested for the second time using stat pak ( chembio hiv1/2 , medford , new york , usa ) . if the serum was reactive for khb hiv-1/2 it was reported as positive . if not a tiebreaker , uni - gold recombigen hiv ( trinity biotech plc , bray , ireland ) , was used as a third and final test to determine the sero - status of the study participants . association between independent variables and sero - positivity was analyzed by bivariate and multivariate logistic regression . the strength of association was calculated using odds ratio at 95% confidence interval ( ci ) . ethical clearance was obtained from university of gondar research and community service core process office . informed written consent was also obtained from each pregnant woman prior to involvement in the study . this cross sectional study was conducted among consecutive pregnant women attending antenatal clinic ( anc ) from may 2010 to october 2011 at the gondar university teaching hospital , northwest ethiopia . structured , pre - tested questionnaire was used to collect socio - demographic characteristics and risk factors associated with t. gondii infection . five milliliter ( ml ) of blood was collected from each pregnant woman and serum was separated . sera were tested in duplicate for anti - toxoplasma antibody using the rapid latex agglutination test kit ( biochcek , inc , ca , spain ) following manufacturer s instructions . positive and negative control tests were done for each batch of test run to ensure kits are working properly and technical procedures are carried out correctly . the serum was also tested for the presence of hiv-1/2 antibodies using rapid hiv diagnostic kit following manufacturer s instructions . results were interpreted following the current algorithm of ethiopia adopted from who for screening of hiv-1/2 antibodies . briefly , the sera were tested using khb hiv-1/2 ( shangai kehua bio - engineering co - ltd , shangai , china ) , when the sera were non - reactive it was reported as negative . when the serum was reactive , it was tested for the second time using stat pak ( chembio hiv1/2 , medford , new york , usa ) . if the serum was reactive for khb hiv-1/2 it was reported as positive . if not a tiebreaker , uni - gold recombigen hiv ( trinity biotech plc , bray , ireland ) , was used as a third and final test to determine the sero - status of the study participants . association between independent variables and sero - positivity was analyzed by bivariate and multivariate logistic regression . the strength of association was calculated using odds ratio at 95% confidence interval ( ci ) . ethical clearance was obtained from university of gondar research and community service core process office . informed written consent was also obtained from each pregnant woman prior to involvement in the study . three hundred and eighty five pregnant women who were attending anc of the gondar university teaching hospital were participated in the study . the majority of the study participants ( 81.6% ) were aged between 20 - 30 years . almost all , 383 ( 99.4% ) had no any information about the disease toxoplasmosis and its transmission ways . other sociodemographic characteristics of the study participants are presented in table 1 . among the 385 study participants , 43 ( 11.2% ) were hiv positive , of whom 38 ( 88.4% ) were also positive for toxoplasmosis ( table 2 ) . of the 385 pregnant women tested , 341(88.6% ) were positive for anti - antibodies of anti - t . pregnant women who kept cats in house had 5 times more risk of toxoplasmosis than those did not ( p=0.00 ; aor = 5.01 95% ci [ 1.50 - 14.11 ] ( table 2 ) . pregnant women who were in their second or third trimester were almost three times risk of t. gondii infection than those who were on the first trimester ( p<0.05 for all ) ( table 2 ) . however , there was no statistically significant association between seropositivity of t. gondii infection and sero - status of hiv , educational status , age , antiretroviral therapy ( art ) , residence , religion or occupation and others . having an experience of stillbirth also did nt show any statistically significant association with the presence of anti - t . the prevalence of t. gondii infection among pregnant women in this study was high ( 88.6% ) irrespective of hiv infection . the prevalence of t. gondii in this study is inconsistent with previous reports from different countries such as italy ( 23.6% ) ( 17 ) , sweden ( ranged 14% to 25.7% ) ( 18 ) , where sero - prevalence of t. gondii is low . low prevalence of toxoplasma infection during pregnancy was also reported from study conducted in korean and sudanese pregnant women of 0.8% and 34.1% , respectively ( 19 , 20 ) . the 88.6% of sero - positivity of t. gondii among pregnant women were comparable to the previous studies conducted among pregnant women in different parts of ethiopia , nazaret ( 60%)(21 ) , jimma ( 83.6% ) ( 14 ) , debrezeit , and ambo ( 81.4% ) ( 12 ) . these finding shows t. gondii infection is not decreasing among pregnant women , this might be due to less emphasis to this infection and inadequate monitoring and evaluation health system . the low level of awareness about its transmission might also contribute to the high prevalence of t. gondii infection . among the risk factors assessed , keeping cats in house this finding is similar with study conducted in czech republic , where cats in the household to be a significant risk factor ( 21 , 22 ) . this study also revealed that , about 88.6 % of hiv patients were sero - positive for t. gondii infection . however , seroprevalence of toxoplasma ranged 4 - 90% were reported from different studies conducted in europe , latin america and africa ( 23 - 31 ) . in asia , the seroprevalence of toxoplasmosis varies from 10 - 50% ( 29 - 32 ) . the present finding with high prevalence of toxoplasma antibodies suggests the need of measuring anti - t . gondii antibodies as a screening test in all hiv / aids patients to reduce the risk of toxoplasma complications including encephalitis is needed in ethiopia . the demonstration that experience of stillbirth showed no significant association with toxoplasmosis among the pregnant women is in agreement with the report of jamshidi makiani et al . ( 34 ) from iran , and these findings substantiated earlier reports that stillbirth is not common in pregnant women who are with toxoplasmosis ( 33 , 34 ) . furthermore , pregnant women who were in their second/ third trimester had almost three times risk of t. gondii infection than those who were on the first trimester . it seems that the difference comes from the level of prenatal cares between the two countries . we guess that attending of the ethiopian pregnant women to antenatal clinics in the first trimester is less than the second and third trimesters , which could be a cause for low frequency of the subjects in the first trimester in our study . furthermore , it is possible that the women attending to the clinics in the first trimester are in higher socioeconomic situation as compared to those attended in the clinic in the 2 and 3 trimesters , thus they are at lower risk of soil and meat transmitted infections . however , further comparative follow - up study is needed to get strong evidence on this issue . keeping cats was the possible risk factors for toxoplasmosis . almost none of the pregnant women know about the disease toxoplasmosis and its transmission ways . therefore , health education should be given for the pregnant women about toxoplasmosis and further researches are recommended to see its transmission dynamics and effect on newborns .