Toxoplasma Infection In Pregnant Women Research Articles

Frequency of Toxoplasma gondii, Rubella, and Cytomegalovirus Antibodies in Pregnant Women in Yazd Province, Iran

Background: TRC (Toxoplasma gondii, rubella virus, and cytomegalovirus [CMV]) infections during pregnancy can lead to serious sequelae in the uterine fetus. Prenatal testing, which includes screening and diagnosis of antibodies to TRC infections, is one of the most important aspects of prenatal care recommended during pregnancy. The aim of the present study was to determine the seroprevalence of TRC infections in pregnant women who attended the antenatal clinic in Yazd province in central Iran. Methods: For this purpose, 8355 sera samples were obtained from pregnant women attending the central laboratory of Yazd province in central Iran and subjected to screening for immunoglobulin G (IgG) and IgM antibodies against TRC using the enzyme-linked immunosorbent assay method. Of these, 4,245, 2,190, and 1,920 pregnant women were screened for anti-Toxoplasma, rubella, and CMV, IgG, and IgM antibodies, respectively. Results: The results revealed that 77.4% (1695/2190) and 78.1% (1500/1920) were positive for anti-rubella and anti-CMV IgG antibodies, and n.o seropositive was detected for anti-rubella and -CMV IgM antibodies. For anti-Toxoplasma antibodies, 20.85% (885/4245), 9.54% (405/4245), and 12.01% (510/4245) were positive for IgG, IgM, and both IgG-IgM antibodies, respectively. In addition, our findings showed the high prevalence of chronic TRC infections and a low recently acquired Toxoplasma infection in pregnant women. Conclusion: Our findings confirmed the high prevalence of chronic TRC infections and a low recently acquired Toxoplasma infection in pregnant women. Hence, observing personal behavioral practices (the source of infection and hygienic measures) are recommended to women at reproductive-age in general and seronegative pregnant women in particular.

A loop-mediated isothermal amplification (LAMP) assay for detection of Toxoplasma gondii infection in women with spontaneous abortion.

The present study aimed to use the loop-mediated isothermal amplification (LAMP) technique in comparison with serological tests to determine the rate ofT. gondii infection in women suffering from spontaneous abortion (SA). A total of 140 women suffering from their first SA were included in this study. The collected aborted fetal remains and blood samples from each patient were examined in sterilized conditions using the LAMP technique and ELISA. Of the 140 women, 80 (57.1%) tested seropositive for anti-Toxoplasma antibodies by ELISA, 72 (51.4%) women tested seropositive for the IgG antibody, 8 (5.7%) tested seropositive for the IgM antibody. Among the eight women who'd had their first SA who tested seropositive for IgM antibody by ELISA, only five cases (62.5%) reported positively to the LAMP test. The difference in the frequency distribution of the LAMP results for measuring the Toxoplasma infection in pregnant women under study was statistically significant (P < 0.001) from the results of the serological test (ELISA). Although there was a significant difference between age and positivity in the LAMP test (P = 0.017), no significant difference was observed between positivity in the LAMP test and other variables. The findings of the present investigation suggest that LAMP is a preferred method for determining Toxoplasma infection in pregnant women suffering from SA compared with other routine serological tests. Even in a field with limited facilities and equipment, this technique can be effective and efficient in accurately and specifically diagnosing Toxoplasma infections in women at high risk of SA.

Development of High Resolution Melting Analysis as a Diagnostic Tool for Molecular Detection of Toxoplasma Infection in Pregnant Women and HIV Positive Cases.

Background:Toxoplasma gondii is an obligate intracellular protozoan with worldwide distribution. Diagnosis of toxoplasmosis is a very critical issue, especially in pregnant women and immunocompromised patients. The aim of this study was rapid detection of T. gondii DNA in peripheral blood samples (PBS) employing HRM technique and using RE gene.Methods:Totally, 242 samples from pregnant women and human immunodeficiency virus (HIV) patients were collected from different hospitals and medical centers of Tehran during Oct 2017 to Dec 2018. High resolution melting analysis (HRM) using partial sequences of repetitive element (RE) gene was done and compared with ELISA test.Results:Overall, 51 were positive for acute toxoplasmosis that among them, 12 and 20 reported as positive in pregnant women and HIV+ patients, respectively using HRM technique. Among 70 patients in chronic phase of disease, 10 and 3 samples were reported as positive for pregnant women and HIV+ patients respectively. From 121 negative control, 3 (4.62%) samples associated with HIV+ patients, showed positive real-time PCR and HRM analysis results.Conclusion:For the first time, HRM technique via employing RE gene was used for detection of T. gondii infection in PBS. This method is suitable, helpful and in parallel with serological methods for early diagnosis of acute as well as active form of toxoplasmosis in pregnant women and HIV+ patients. The use of techniques based on melt curve and through employing next-generation dyes for diagnosis of T. gondii would be accessible for patients in developing countries.

Interleukin-8 Level in Pregnant Women with Toxoplasmosis in Kirkuk City

A cross sectional study was carried out in Kirkuk city from 15th of June 2018 to 15th of December 2018. The study included 100 pregnant women and 50 healthy individuals. Their ages ranged between 17-45 years old who were admitted to Kirkuk general hospital.. Molecular tests for real-time PCR and serological testing for detection specific Toxoplasma gondii IgM and IgG and Interleukin-8 level by using ELISA technique was done for patients and control. The study showed that the highest rate of anti T. gondii IgM+ IgG- antibodies (10%) was recorded among pregnant women compared with 8% in the control group, while 22% of pregnant women were IgM+IgG+ compared 6.5% of the healthy control group. The study revealed that 40.91% of pregnant women with positive ELISA was positive by PCR compared with 0% of patients with negative ELISA results. The study showed that the highest rate of T. gondii infection (diagnosed by PCR) were recorded among pregnant women at age group 27-36 year (22.55%) and the lowest rate was within the age group 17-26 year. The highest mean level of IL-8 recorded PCR +ve groups, in pregnant women (79.2 ±53.2 ng/ml) compared with PCR –ve groups. There was a highly significant differences of IL-8 between pregnant women and the control group. The study showed that the highest mean level of IL-8 (77.61±60.4 ng/ml), in pregnant at 2nd trimester of pregnancy, followed by 3rd trimester. This study was concluded that a highly elevation of IL-8 level was correlated Toxoplasma infection in pregnant women and real time PCR is golden method in diagnosis of toxoplasmosis..

Age-related prevalence of toxoplasmosis among pregnant women in Hatay: Estimation depending on model

Toxoplasmosis, caused by the obligate intracellular protozoan Toxoplasma gondii, is a common parasitic infection affecting approximately one-third of the world population. T.gondii infections are usually acquired by ingesting raw or insufficiently cooked meat and from unwashed fruits and vegetables contaminated with soil or water with cat feces. Primary infection acquired during pregnancy can cause severe congenital abnormalities in the fetus such as neurologic and ocular malformations, abortion, or stillbirth according to the degree of infection. The aim of this study was to estimate the prevalence and rate of seroconversion of T.gondii IgG antibodies in a selected population of pregnant women in Hatay by using a mathematical model. T.gondii-specific serological screening test results of 11.564 pregnant women who have attended the Private Antakya Mosaic Obstetrics and Gynecology Hospital between 01.04.2009 and 31.04.2016 were analysed in the study. The prevalence of T.gondii-specific IgG antibodies in the studied population were found as 48.70% (95% CI, 0.48-0.50). The prevalence of T.gondii-specific IgG antibodies were increased linearly with age in our study population. The relationship between age and prevalence was statistically significant (p< 0.001). The age-specific rate of seroconversion was estimated as 0.8% for T.gondii infection in pregnant women. It was observed that the rate of T.gondii-specific IgG antibodies decreased from 55.12% (95% Cl, 0.52-0.57) detected in 2009 to 42.22% (95% Cl, 0.37-0.46) in 2016. The estimated number of cases carrying the risk of primer T.gondii infection was calculated as 69 in the study population. Our results have suggested that the prevalence of T.gondii-specific antibodies is high among pregnant women in Hatay. Early maternal diagnosis and treatment methods may reduce the risk of transplacental transmission during pregnancy. The on time diagnosis can only be achieved with prenatal serological screening. The knowledge of the incidence and prevalence of toxoplasma infection in pregnant women plays a crucial role in estimating the burden of the disease and evaluating the effectiveness of the public health protection policies including screening programmes. Expanding of training activities, drawing attention to hygiene, taking nutritional precautions and increasing awareness of toxoplasmosis in pregnant women are important to prevent congenital toxoplasmosis or minimize the disease.

Comparative study on Toxoplasma infection between Malaysian and Myanmar pregnant women.

BackgroundToxoplasma gondii, an obligate intracellular protozoan parasite, causes a disease called toxoplasmosis which can sometimes be acquired congenitally by a newborn from an infected mother. This study aimed to determine the seroprevalence of Toxoplasma infection and its associated risks among 219 and 215 pregnant women from Malaysia and Myanmar, respectively.MethodsAnti-Toxoplasma IgG and IgM antibodies were screened by using standard commercial ELISA kits. The socio-demographic, obstetrics and risk factors associated with Toxoplasma infection data were compared between the two countries.ResultsThe overall prevalence of Toxoplasma infection in Malaysian pregnant women (42.47%; 95% CI = 36.11-49.09) was significantly higher (p < 0.05) than Myanmar pregnant women (30.70%; 95% CI = 27.92-37.16). By univariate analysis, this study identified that age group, education, parity, awareness on toxoplasmosis and consumption of undercooked meat were significantly associated (p < 0.05) with Toxoplasma seropositive Malaysian pregnant women but none of these factors associated with Toxoplasma seropositive Myanmar pregnant women. In comparison using univariate analysis between the two countries, it was found that Toxoplasma seropositive Malaysian pregnant women was associated with aged 30 years and above, secondary or lower-secondary level of education, the third trimester of pregnancy, having one child or more, lacking awareness of toxoplasmosis, absence of bad obstetrics history, having no history of close contact with cats or soil, living on a farm and also consumption of undercooked meat, unpasterized milk or untreated water. Avidity measurement was used to confirm the stages of Toxoplasma infection in pregnant women who were positive for both IgG and IgM antibodies and found all were infected in the past.ConclusionFrom our study, Toxoplasma screening and its risk measurement in pregnant women is firmly recommended for monitoring purposes and assisting proper management, including diagnosis and treatment during antenatal period. Also, it is necessary to initiate preventive measures for Toxoplasma infection among reproductive-age women in general and seronegative pregnant women in particular. Avidity measurement should be incorporated in Toxoplasma routine screening, especially with the availability of a single serum sample to assist in the diagnosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-014-0564-9) contains supplementary material, which is available to authorized users.

Knowledge and practice on Toxoplasma infection in pregnant women from Malaysia, Philippines, and Thailand.

Toxoplasma gondii, is one of the infectious agents of congenital TORCH infections, causes severe clinical outcomes in fetus and newborns. Nevertheless this life-threatening parasitic disease is preventable by simple preventive measures related to lifestyle during pregnancy. We aim to study on the knowledge about toxoplasmosis and practices that prevents this infection among the pregnant women. Total of 2598 pregnant women from Malaysia, Philippines, and Thailand were randomly surveyed to determine the knowledge and their practices on Toxoplasma infection. The questionnaire covered respondents' general information and knowledge on plausible risks factors, symptoms, timing of infection, prevention knowledge, and preventive behavior regarding Toxoplasma infection. Majority of these pregnant women were in their age group of 20–29 years (50.9%), completed secondary level of education (51.7%), in their second trimester of pregnancies (38.1%), non-parous (36.6%), and had no history of abortion (90.4%). Based on this survey, only 11% of these pregnant women had read, heard, or seen information regarding toxoplasmosis and 3.5% of them were aware of being tested for the infection. A small percentage of these pregnant women knew that T. gondii were shed in the feces of infected cats (19.4%) and sometimes found in the raw or undercooked meat (11.0%). There was 16.1% of responding women knew that toxoplasmosis is caused by an infection. Demographic profiles such as age group, level of education, pregnancy term, and number of children of the pregnant women showed significant association with their responses toward prevention knowledge and preventive behavior related questions (P < 0.05). Thus, it is suggested that health education on toxoplasmosis and primary behavioral practices should be consistently offered to reproductive age women in general and pregnant women in particular. This information could help to reduce vertical transmission of Toxoplasma infection during pregnancy.

Toxoplasma infection in pregnant women: a current status in Songklanagarind hospital, southern Thailand.

BackgroundToxoplasmosis, being one of the TORCH’s infections in pregnant women, is caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. This parasitic infection in pregnancy congenitally causes severe outcomes to their fetus and newborn. This study aimed to determine the seroprevalence and stages of Toxoplasma infection in pregnant women and its associated risks exposures.MethodsThe study was conducted within the pregnant women attending the antenatal clinic (ANC) at Songklanagarind hospital, Hat Yai, Songkhla province, Thailand. The sera of a total of 760 consecutive pregnant women were screened using standard commercial ELISA kits for detection of anti-Toxoplasma IgG and IgM antibodies. IgG avidity in the seropositive for both anti-Toxoplasma IgG and IgM antibodies were also assessed. The pregnant women’s socio-demographic, obstetrics and risk factors associated with Toxoplasma seropositivity data were analyzed using univariate and multivariate analyses.ResultsFrom the total 760 pregnant women, 190 (25%, 95% CI = 22.05-28.20) were positive for anti-Toxoplasma antibodies. Of these, 167 (22.0%, 95% CI = 19.0-25.0) were positive for only anti-Toxoplasma IgG antibody and 23 (3.0%, 95% CI = 2.0-4.0) were positive for both anti-Toxoplasma IgG and IgM antibodies. All these samples were high avidity, indicated the infection occured prior to four to five months. By applying statistical univariate analysis, age group, occupation and sources of drinking water showed a significant association with Toxoplasma seropositivity (p < 0.05). Multivariate logistic regression analysis further indicated that the significant factors associated with Toxoplasma seropositivity are age ≥26 (OR = 1.65, 95% CI = 1.11-2.44), working as laborer (OR = 1.57, 95% CI = 1.13-2.18) and drinking unclean (piped/tap/rain) water (OR = 1.75, 95% CI = 1.08-2.84).ConclusionThe pregnant women in the active age group, working as laborers and exposure to unclean drinking water from various sources were at higher risk of Toxoplasma infection. Therefore, health education and the awareness of risk exposures regarding this parasitic disease are required to minimize the effects of this parasitic infection in pregnant women as well as in the general population.

Comparative study on Toxoplasma infection between Malaysian and Myanmar pregnant women

Toxoplasma gondii, an obligate intracellular protozoan parasite, causes a disease called toxoplasmosis which can sometimes be acquired congenitally by a newborn from an infected mother. This study aimed to determine the seroprevalence of Toxoplasma infection and its associated risks among 219 and 215 pregnant women from Malaysia and Myanmar, respectively. Anti-Toxoplasma IgG and IgM antibodies were screened by using standard commercial ELISA kits. The socio-demographic, obstetrics and risk factors associated with Toxoplasma infection data were compared between the two countries. The overall prevalence of Toxoplasma infection in Malaysian pregnant women (42.47%; 95% CI = 36.11-49.09) was significantly higher (p < 0.05) than Myanmar pregnant women (30.70%; 95% CI = 27.92-37.16). By univariate analysis, this study identified that age group, education, parity, awareness on toxoplasmosis and consumption of undercooked meat were significantly associated (p < 0.05) with Toxoplasma seropositive Malaysian pregnant women but none of these factors associated with Toxoplasma seropositive Myanmar pregnant women. In comparison using univariate analysis between the two countries, it was found that Toxoplasma seropositive Malaysian pregnant women was associated with aged 30 years and above, secondary or lower-secondary level of education, the third trimester of pregnancy, having one child or more, lacking awareness of toxoplasmosis, absence of bad obstetrics history, having no history of close contact with cats or soil, living on a farm and also consumption of undercooked meat, unpasterized milk or untreated water. Avidity measurement was used to confirm the stages of Toxoplasma infection in pregnant women who were positive for both IgG and IgM antibodies and found all were infected in the past. From our study, Toxoplasma screening and its risk measurement in pregnant women is firmly recommended for monitoring purposes and assisting proper management, including diagnosis and treatment during antenatal period. Also, it is necessary to initiate preventive measures for Toxoplasma infection among reproductive-age women in general and seronegative pregnant women in particular. Avidity measurement should be incorporated in Toxoplasma routine screening, especially with the availability of a single serum sample to assist in the diagnosis.

Disposable Amperometric Immunosensor for Detecting Toxoplasma Gondii-Specific IgM Based on Graphene and CeO2-Au

Toxoplasma gondii-specific IgM (Tg-IgM) is a sensitive and reliable marker for early diagnosing toxoplasmosis infection in pregnant women. In this study, a disposable amperometric immunosensor for sensitive detecting Tg-IgM was constructed based on graphene (GP) and CeO2-Au nanoparticle. The GP was treated with chitosan (CS) to obtain a stable graphene-chitosan (GPCS) composite membrane. The CeO2-Au nanoparticle which was used for the preparation of the amperometric immunosensor was synthesized by the hydrothermal method. GPCS composite membrane was first assembled onto the screen-printed carbon electrode (SPCE) for adsorbing the CeO2-Au nanoparticle. The toxoplasma gondii antigen (Tg-Ag) was subsequently adsorbed by CeO2-Au nanoparticle to obtain the proposed immunosensor. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were employed to characterize the construction process of the immunosensor. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) were used to study the electrochemical properties of the immunosensor. The results indicated that, CS employed in this study improved the dispersion and homogeneity of GP, as well as enhance the stability of the proposed immunosensor. The use of GPCS composite membrane and CeO2-Au nanoparticle had good conductivity and prominent biocompatibility, which excellently improved the sensitivity of the immunosensor. In the optimal conditions, the proposed immunosensor can be applied to quantify the concentration of Tg-IgM in a wide linear range from 7.5×10 AU•mL to 24 AU•mL with a correlation coefficient of -0.998 and a low detection limit of 4.4×10 AU•mL (S/N=3). The novel proposed immunosensor for detecting Tg-IgM in human serum specimens with satisfactory results had also been proved. In addition, the Tg-IgM contents determined by the immunosensor agreed well with the ELISA measurement. Furthermore, the proposed amperometric immunosensor exhibited some advantages, such as high selectivity, long-term stability, good repeatability, low sample consumable, and short analysis time, which were suitable for detecting toxoplasma infection in pregnant women.

Antenatal screening forToxoplasma gondiiinfection at a tertiary care hospital in Riyadh, Saudi Arabia

BACKGROUND AND OBJECTIVES:Congenital toxoplasmosis is associated with significant morbidity and mortality. This study investigates the prevalence of toxoplasmosis among pregnant women.DESIGN AND SETTING:A retrospective study at King Khalid University Hospital, Riyadh from September 2009 to August 2010.PATIENTS AND METHODS:Laboratory data of 2176 pregnant women screened for Toxoplasma gondii in the antenatal care unit were assessed during the study period. The mean (SD) age of the women and the duration of pregnancy were 25 (7.3) years and 18 (7.7) weeks, respectively. Data were extracted for the presence or absence of anti-T gondii immunoglobulin G (IgG) and IgM antibodies.RESULTS:Of 2176 sera tested, 1351 (62%) did not show any evidence of exposure to T gondii. The remaining 825 (38%) samples tested positive for anti-T gondii IgG antibodies, and none was found to have anti-T gondii IgM antibodies in the serum. These data reveal that a significantly high number of women in the antenatal care unit at King Khalid University Hospital in Riyadh had been exposed to T gondii.CONCLUSION:A high prevalence of toxoplasmosis among pregnant women warrants multicenter community-based investigations for assessment of T gondii infection and identification of risk factors for transmission of toxoplasmosis in general, and particularly during pregnancy.

Sensorineural hearing loss due to Toxoplasma gondii in children: a case–control study

Sensorineural hearing loss (SNHL) can follow congenital toxoplasmosis. Treatment in the first year of life is associated with diminished occurrence of this sequel. In various parts of Iran, the prevalence of antibodies to Toxoplasma gondii ranges from 24% to 57.7%. We evaluate the possible role of Toxoplasma gondii infection on the occurrence of SNHL in children. This case-control study was performed in a tertiary care center in Tehran between 2002 and 2003. This study was carried out based on diagnostic parameters of the American Academy of Otolaryngology criteria for SNHL and a healthy control group. We compared the specific Toxoplasma gondii antibodies (IgM & IgG) measured by ELISA in 95 blood samples of infants with SNHL and 63 healthy matched infants. Acute (IgM) and previous (IgG) immunity to Toxoplasma gondii was found in 12 and 21.2% of SNHL children, respectively. Most cases with previous infections (IgG positive) were children aged less than 1 year old (i.e. maternal immunity), but acute infection (IgM positive) was higher in 3-5 year old age group. Acute infection (IgM) was significantly more frequent in the SNHL group, and previous immunity was higher in the controls (CI 95%, P-value = 0.01; 0.01). With respect to seropositive children, as we were unable to differentiate congenital from acquired cases, we recommend prevention of congenital toxoplasmosis by treatment of Toxoplasma infection in pregnant women and treatment of acquired Toxoplasma gondii infection after birth to minimise the risk of SNHL in children.

Serodiagnosis of recently acquired Toxoplasma gondii infection in pregnant women using enzyme-linked immunosorbent assays with a recombinant dense granule GRA6 protein

Indirect immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) with a recombinant GRA6 protein of Toxoplasma gondii were developed and evaluated for accurate diagnosis of recently acquired infection in pregnant women. According to the results from Toxoplasma serodiagnostic tests, women were classified into 3 groups representing acute (group I), chronic (group II), or no Toxoplasma infection (group III). To discriminate group I from group II sera, the GRA6–IgG-ELISA reached sensitivity and specificity of 87.5% and 94.1%, respectively. Although 22 (91.7%) of 24 group I sera were positive by the GRA6–IgM-ELISA, only 1 (2.9%) of 34 group II sera scored positive. The GRA6–IgM-ELISA displayed a meaningful correlation with Vidas Toxo IgM and exhibited higher specificity (97.1%) than Euroimmun IgM ELISA (88.2%) (Euroimmun, Lübeck, Germany) for detection of recent infection. These results demonstrate that IgG and IgM ELISA with rGRA6 are useful to identify and discriminate recent from past Toxoplasma infection in pregnant women.

Usefulness of Toxoplasma gondii recombinant antigens (GRA1, GRA7 and SAG1) in an immunoglobulin G avidity test for the serodiagnosis of toxoplasmosis

The precise diagnosis of an acute and recent Toxoplasma infection in pregnant women and the newborn child is important before treatment. This study describes a new Toxoplasma gondii IgG avidity test based on a combination of recombinant GRA1, GRA7 and SAG1 antigens and shows that this test is useful for diagnostic purposes and may replace the lysed, whole-cell antigens. Although more sera need to be tested, the results obtained here suggest that the IgG avidity test performed with rec-antigens correlated more with the stage of a T. gondii infection than the IgG avidity results obtained with the lysed, whole-cell antigen test, the VIDAS Toxo IgG avidity (bioMérieux).

Sources of toxoplasma infection in pregnant women: European multicentre case-control study. European Research Network on Congenital Toxoplasmosis.

Objective: To determine the odds ratio and population attributable fraction associated with food and environmental risk factors for acute toxoplasmosis in pregnancy.Design: Case-control study.Setting: Six large European cities.Participants: Pregnant women...

Congenital toxoplasmosis: Current status of diagnosis, treatment, and prevention

Congenital toxoplasmosis, like congenital syphilis and perinatally acquired human immunodeficiency virus infection, usually is not apparent clinically in the newborn, and, because screening is seldom performed, the condition seldom is entertained as a diagnosis. Early recognition and treatment of Toxoplasma infection in pregnant women may prevent transplacental infection and avoid its clinical expression when the infant reaches young adulthood. New programs for screening and early diagnosis have awakened interest among pediatricians in early treatment of this infection. This article describes the parasite that causes the infection, Toxoplasma gondii; its epidemiology; the clinical manifestations of infection; diagnostic tests; treatment; and prevention. Copyright © 2000 by W.B. Saunders Company

Prevention of Toxoplasma Infection in Pregnant Women and Their Fetuses

Prevention of Toxoplasma Infection in Pregnant Women and Their Fetuses

The evaluation of new services: possibilities for preventing congenital toxoplasmosis.

We examine the resource implications of two potential health services aimed at preventing congenital toxoplasmosis: a screening service involving serological surveillance for toxoplasma infection in pregnant women and its prophylactic treatment; and a health education campaign to help pregnant women avoid acquiring toxoplasma infection, through advice about special precautions regarding hygiene. Measuring the costs and benefits of prevention is complicated by uncertainty of the incidence of congenital toxoplasmosis in the United Kingdom, the extent of its harmful manifestations--mental and visual handicap--and the effectiveness of preventive measures. Hence an important aspect of this study is that it exemplifies the use of 'sensitivity analysis' as an aid to evaluation in the absence of hard data. We find that a screening service would seem unlikely to save resources, but that a health education campaign would seem much more likely to do so and further assessment of its potential effectiveness would be valuable.