Risk Of Congenital Toxoplasmosis Research Articles

Methods of Laboratory diagnostics of intracellular protozoan parasite Toxoplasma gondii in pets of the Felidae family

The main source of the spread of the invasive origin and the entry of toxoplasma oocysts into the external environment are pets - cats, infection of all types of mammals is possible. Transmission of the pathogen can occur during contact with animals, as well as when using thermally insufficiently processed meat. The main danger of toxoplasmosis is for pregnant cats (primary infection during pregnancy is associated with the risk of congenital toxoplasmosis and fetal development disorders), as well as with a pronounced decrease in immunity. In domestic pets of the feline family, pathogens of toxoplasmosis are at different stages of development, therefore oocysts can be detected by examining freshly excreted feces by the Fulleborn method or by detecting antibodies in the blood by enzyme immunoassay (ELISA) using the Immunorun Antigen Detection Kit canine Heartworm test system, manufactured by Biogal - Galed labs (Israel). The material for this work was the results of laboratory tests of blood and faecal samples from 73 pets (46 females, 27 males) aged 6 months to 10 years and one-time studies by the Fulleborn method of faecal samples from 109 different-aged pets (69 females, 40 males) examined in 2020-21 in the veterinary clinic of the city of Yakutsk due to other diseases and preventive examination.

Association between lymphadenopathy after toxoplasmosis seroconversion in pregnancy and risk of congenital infection.

The aim of the study was to describe the pregnancy outcome of a large cohort of women with toxoplasmosis seroconversion in pregnancy and to investigate the relation between maternal lymphadenopathy and risk of congenital toxoplasmosis (CT). This was a retrospective study involving women with confirmed toxoplasmosis seroconversion in pregnancy between 2001 and 2017. Women were clinically evaluated for lymphadenopathy and classified as follows: lymphadenopathy absent (L-) or lymphadenopathy present (L+). The mothers were treated and followed-up according to local protocol, and neonates were monitored at least for 1year in order to diagnose CT. A total of 218 women (one twin pregnancy) were included in the analysis. Pregnancy outcome was as follows: 149 (68%) of children not infected, 62 (28.3%) infected, 4 (1.8%) first trimester termination of pregnancy, 2 (0.9%) first trimester miscarriages, and 3 (1.4%) stillbirths (of which one already counted in the infected cohort). 13.8% of women were L+ , and they were nearly three times more likely to have a child with CT compared to L- women (aOR, 2.90; 95%CI, 1.28-6.58). Moreover, the result was still statistically significant when the analysis was restricted to 81 children whose mothers were clinically examined and received treatment within 5weeks from estimated time of infection. In conclusion, there is a positive association between L+ status in pregnant women, and risk of CT also confirmed when restricting the analysis to women with early diagnosis of seroconversion and treatment. This data could be very useful in counselling pregnant women with toxoplasmosis seroconversion and lead to direct a more specific therapeutic and diagnostic protocol.

Seroprevalence, risk factors and impact of Toxoplasma gondii infection on haematological parameters in the Ashanti region of Ghana: a cross-sectional study.

Background: Toxoplasma gondii is an obligate, intracellular, apicomplexan parasite that causes toxoplasmosis. Although the global prevalence of toxoplasmosis has been estimated to be approximately 30%, there is limited seroprevalence data in Ghana, with a dearth of information on the impact of T. gondii on haematological parameters in exposed persons. Methods: Questionnaires were administered to 300 consenting individuals to obtain demographic information and assessment of their risk of exposure to T. gondii. Using anti- T. gondii IgG/IgM combo test kits, seropositivity to parasite-specific IgG and/or IgM was determined. A haematological analyser was used to measure haematological parameters. Results: There was an overall seroprevalence of 50.3% (n=151), with 49.7% (n=149) of the study participants seropositive for IgG and 1% (n=3) testing positive for IgM. Furthermore, the observed seroprevalence among pregnant women was 56.4% (n=62). With regard to settlement type, a seroprevalence of 55.6% was observed in the rural community, 50.6% in the peri-urban community and 47.1% in the urban community. The study identified cat ownership, contact with cat litter, contact with raw meat [RR (95% CI: 1.76 (1.23-2.53), 1.66 (1.03-2.67), 1.25(1.00-1.57)] and age (p<0.001) as risk factors for infection. Analyses of haematological data revealed significant reduction in the white blood cell, lymphocytes and mean corpuscular volume levels in seropositive males (p=0.0223, 0.0275, and 0.0271) respectively. Only the mean corpuscular volume of seropositive females reduced significantly as compared to the seronegative counterparts (p=0.0035). Conclusions: About half of the study population, including women of reproductive age carried antibodies against T. gondii, raising concerns about the risk of congenital toxoplasmosis and anaemia. We, therefore, recommend that screening for Toxoplasma gondii be included in the routine screening of pregnant women seeking antenatal care and further investigation should be conducted on the haematological implications of infection in humans.

Seroprevalence, risk factors and impact of Toxoplasma gondii infection on haematological parameters in the Ashanti region of Ghana: a cross-sectional study

Background: Toxoplasma gondii is an obligate, intracellular, apicomplexan parasite that causes toxoplasmosis. Although the global prevalence of toxoplasmosis has been estimated to be approximately 30%, there is limited seroprevalence data in Ghana, with a dearth of information on the impact of T. gondii on haematological parameters in exposed persons. Methods: Questionnaires were administered to 300 consenting individuals to obtain demographic information and assessment of their risk of exposure to T. gondii. Using anti- T. gondii IgG/IgM combo test kits, seropositivity to parasite-specific IgG and/or IgM was determined. A haematological analyser was used to measure haematological parameters. Results: There was an overall seroprevalence of 50.3% (n=151), with 49.7% (n=149) of the study participants seropositive for IgG and 1% (n=3) testing positive for IgM. Furthermore, the observed seroprevalence among pregnant women was 56.4% (n=62). With regard to settlement type, a seroprevalence of 55.6% was observed in the rural community, 50.6% in the peri-urban community and 47.1% in the urban community. The study identified cat ownership, contact with cat litter, contact with raw meat [RR (95% CI: 1.76 (1.23-2.53), 1.66 (1.03-2.67), 1.25(1.00-1.57)] and age (p<0.001) as risk factors for infection. Analyses of haematological data revealed significant reduction in the white blood cell, lymphocytes and mean corpuscular volume levels in seropositive males (p=0.0223, 0.0275, and 0.0271) respectively. Only the mean corpuscular volume of seropositive females reduced significantly as compared to the seronegative counterparts (p=0.0035). Conclusions: About half of the study population, including women of reproductive age carried antibodies against T. gondii, raising concerns about the risk of congenital toxoplasmosis and anaemia. We, therefore, recommend that screening for Toxoplasma gondii be included in the routine screening of pregnant women seeking antenatal care and further investigation should be conducted on the haematological implications of infection in humans.

Seroprevalence, risk factors and impact of Toxoplasma gondii infection on haematological parameters in the Ashanti region of Ghana: a cross-sectional study

Background: Toxoplasma gondii is an obligate, intracellular, apicomplexan parasite that causes toxoplasmosis. Although the global prevalence of toxoplasmosis has been estimated to be approximately 30%, there is limited seroprevalence data in Ghana, with a dearth of information on the impact of T. gondii on haematological parameters in exposed persons. Methods: Questionnaires were administered to 300 consenting individuals to obtain demographic information and assessment of their risk of exposure to T. gondii. Using anti-T. gondii IgG/IgM combo test kits, seropositivity to parasite-specific IgG and/or IgM was determined. A haematological analyser was used to measure haematological parameters. Results: The participants included 58 males and 242 females, and ranged in age from 6 months to 84 years, with a median age of 27 years. There was an overall seroprevalence of 50.3% (n=151), with 49.7% (n=149) of the study participants seropositive for IgG and 1% (n=3) testing positive for IgM. Furthermore, the observed seroprevalence among pregnant women was 56.4% (n=62). With regards to the different communities in which the hospitals were located, a seroprevalence of 55.6% was observed in the rural community, 50.6% in the peri-urban community and 47.1% in the urban community. The study identified cat ownership, contact with cat litter [RR (95% CI: 1.76 (1.23-2.53), 1.66 (1.03-2.67), 1.25(1.00-1.57)] and age (p&lt;0.001) as risk factors for infection. Analyses of haematological data also revealed significant differences between the red blood cell counts (p=0.038) and mean corpuscular volumes (p=0.0007) of seropositive and seronegative study participants. Conclusions: About half of the study population, including a significant number of women of reproductive age carried antibodies against T. gondii, raising questions about the risk of congenital toxoplasmosis, as well as possible links to anaemia. We, therefore, recommend that screening for Toxoplasma gondii be included in the routine screening of pregnant women seeking antenatal care.

Male-to-Female Transmission of Toxoplasmosis Between Sexual Partners

Background: Toxoplasmosis is one of the most widespread human parasitoses in the developed countries. Toxoplasma gondii has been found in the ejaculate of various animals, including human. Sexual transmission of this zoonosis has been confirmed in several animal species but not in human. Nevertheless, a large part of infections in mothers of children with congenital toxoplasmosis cannot be explained by contact with any currently known risk factor, while high prevalence of toxoplasmosis has been observed in the fathers of children with this diagnosis. This indirect evidence supports the hypothesis of sexual transmission of toxoplasmosis in humans. Methods: We compared the prevalence of toxoplasmosis in couples and analysed various risk factors for toxoplasmosis including the infection status of sexual partner. By comparing the risk factors for Toxoplasma infection in men and women, we tested the hypothesis of man-to-woman sexual transmission of toxoplasmosis. Findings The prevalence of toxoplasmosis in women with infected male partners (25·6%; n=156) was higher than the prevalence in women with uninfected male partners (18·2%; n=477; p=0·023). Partner's infection therefore seems to be a risk factor for infection in women (n=593; odd ratio=1·602; p=0·022) but not in men (n=573; odds ratio=1·064; p=0·816). Interpretation: Our results support the hypothesis of sexual transmission of toxoplasmosis from men to women. The risk may seem relatively low, but transmission can occur during unprotected sexual intercourse, which may be the time of conception. Due to the risk of congenital toxoplasmosis, even a lower risk of infection than that observed in our study can represent a serious public health problem. Funding Statement: Charles University Grant Agency (number 104218), Czech Science Foundation Grant (number 18-13692S), Charles University Research Centre program (number 204056) and RVO-VFN64165 from the Ministry of Health of the Czech Republic. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: Informed consent was obtained from all participants. Blood samples for serological testing for toxoplasmosis were taken during a routine examination. This research has been repeatedly approved by Ethics Committee of General University Hospital in Prague (No. 384/16; 92/17) and by Institutional review board of Faculty of Science, Charles University (No. 2015/29).

Recém-nascidos com risco de toxoplasmose congênita, revisão de 16 anos

AIMS: To analyze the data on pregnancies with risk of congenital toxoplasmosis and to investigate the newborns' outcome, in a level II hospital in Portugal.METHODS: A cross-sectional retrospective study included newborns at risk for congenital toxoplasmosis and their mothers, whose delivery occurred between January 2000 and December 2015. The inclusion criteria were mother with seroconversion to toxoplasmosis during pregnancy or first serum sample with positive specific IgM and IgG. The diagnosis of congenital toxoplasmosis was defined by positive specific IgM at birth and/or polymerase chain reaction positive in amniotic fluid and/or persistence of specific IgG up to 12 months of life. Congenital toxoplasmosis was defined as symptomatic when clinical findings were attributed to the disease. Chi-square or Fisher's exact tests were used to test associations between variables, assuming statistical significance when p &lt;0.05.RESULTS: There were 39,585 live births in the study period and 98 cases with risk of congenital toxoplasmosis were identified, of which 89 completed the follow-up. The prevalence of anti-T. gondii IgG in the pregnant women was 26% (95% confidence interval [CI] 24-27%). Twenty-two cases of congenital toxoplasmosis (5.6 per 10,000 live births, 95%CI 3.5-8.5 per 10,000) were confirmed. Of the 22 newborns, 18 (82%, 95%CI 61-93%) were symptomatic. The most frequent clinical findings were intracranial calcification (64%), hepatomegaly and / or elevation of transaminases (32%) and retinochoroiditis (14%). Cerebral lesions were more frequent when maternal infection was documented in the first and second trimester compared to the third trimester (p=0.018). In 31 cases (35%), the pregnant women were treated from the time of diagnosis until delivery with spiramycin, and no differences were found regarding the rate of vertical transmission or the appearance of clinical manifestations among the newborns of treated and non-treated mothers treated.CONCLUSIONS: The prevalence of congenital toxoplasmosis was higher than that reported in other European countries. The prevalence of intracranial calcifications was higher than that described in the literature, whereas retinochoroiditis and strabismus occurrence was lower. Brain lesions in newborns were more frequent in first- and second-trimester infections. There was no difference in the rate of vertical transmission and in the occurrence of clinical manifestations among newborns whose mothers received spiramycin during gestation and those whose mothers did not receive treatment.

Risk of congenital toxoplasmosis in women with low or indeterminate anti-Toxoplasma IgG avidity index in the first trimester of pregnancy: an observational retrospective study

ObjectivesCongenital toxoplasmosis (CT) affects one to ten fetuses per 10 000 live newborns in western countries. Without knowing pre-conception serostatus, it is hard to date the infection when anti-Toxoplasma IgG and IgM antibodies are positive at first screening. Although a high IgG avidity index (AI) in the first trimester excludes CT, the same cannot be said of intermediate and low AI. The aim of this study was to estimate the risk of CT when intermediate or low AI is detected in the first trimester of pregnancy. MethodsOur observational retrospective study enrolled women with positive anti-Toxoplasma IgG and IgM, and low/intermediate AI in the first trimester of gestation seen at two reference centres in northern Italy between 2006 and 2015. All women received spiramycin. When requested by women, a sample of fluid obtained through amniocentesis was tested with a commercial real-time PCR. CT was defined by positive PCR result confirmed on aborted materials or by newborn follow up. ResultsOverall, 778 first-trimester pregnant women were included; AI was low in 532/778 (68%) and intermediate in 246/778 (32%). Amniocenteses were performed in 528/778 (67.9%), with no fetal loss. In all, 19/778 (2.4%) miscarriages and 15/778 (1.9%) pregnancy terminations were recorded; 9/778 (1.6%) were lost to follow up. In two women, PCR on amniotic fluid was positive, but CT was confirmed in only 1/747 cases (0.13%, 95% CI 0.02%–0.75%). ConclusionIn our study, the risk of CT was much lower than anticipated. These data must be considered when counselling these women.

Prevalence of Anti-Toxoplasma gondii Antibodies in Young Iranians: The CASPIAN III Study

Background: Toxoplasmosis is a worldwide neglected tropical and sub-tropical infection caused by Toxoplasma gondii (T. gondii). Most of the previous studies on the seroprevalence of T. gondii in Iran have been done at provincial level and on specific populations, including pregnant females. Socioeconomic parameters are associated with the prevalence of this disease. In this study, the authors evaluated the presence of anti-T. gondii antibodies and the related risk factors in Iranian adolescents. Methods: This was a cross-sectional study on serum samples from the third Iranian national school-based survey (the CASPIAN III study), which included 10- to 18-year-old students. Participants were selected by multistage sampling from 27 Iranian provinces. In this study, serum samples of 882 adolescents from 16 provinces were randomly selected and examined for IgG and IgM antibodies against T. gondiiby theEnzymeLinked Fluorescent Assay (ELFA).Demographicandsocioeconomic factors related to T. gondii infection were gathered using the global school-based health survey (GSHS) questionnaire. Results: The overall T. gondii IgGandIgMseropositivitywas56.3 (95 CI: 53.4 to 59.2)and3.7 (95CI: 2.7 to 4.9), respectively. In multivariate logistic regression model, family size was statistically associated with seroprevalence of anti T. gondii IgG. Living in crowded households (households with more than 4 people vs. households with less than 4 people) increased the risk of seropositivity of T. gondii (OR: 1.40, 95 CI: 1.10 to 1.99). Conclusions: The results of this study indicate that about 40 of Iranian adolescents have not had contact with the T. gondii, thus the risk of congenital toxoplasmosis might be high in young females. Also, household size was the main factor associated with T. gondii infection. Preventive strategies and health education in Iranian adolescents are recommended. © 2017, Pediartric Infections Research Center.

Congenital toxoplasmosis: Clinical features, outcomes, treatment, and prevention.

Toxoplasmosis is caused by a coccidian parasite, Toxoplasma gondii. The parasite is highly prevalent both in humans and in warm-blooded animals. Cat family animals are definitive host, and these animals excrete the infective oocysts in their feces. Humans, though not definitive host, get infection by consuming water or food contaminated with cat feces. Rarely, infection can also take place through transfusing the infected blood, through transplantation of infected organs, or transplacentally from infected mother to fetus. Transplacental infection can cause congenital infection with varied degree of clinical manifestations, which depend on the age of fetus when infection took place. Diagnosis of congenital toxoplasmosis is difficult to establish until it is suspected and laboratory investigations are carried out. In more than 75% of cases, acute infection is missed due to very mild or unnoticeable clinical symptoms and signs. In India, a prevalence rate of 22.4% (8.8-37.3%) has been reported with an overall IgM positivity of 1.43%. It is estimated that approximately between 56,737 and 176,882 children per year are born in India with a possible risk of congenital toxoplasmosis. The diagnosis of congenital toxoplasmosis can be made by serological methods which are most commonly used. The other methods are parasite isolation by culture and molecular methods. Toxoplasmosis is treatable and transplacental transmission can be prevented by spiramycin, which concentrates in the placenta. However, if infection has done any damage to the fetus or the parasite has passed the placenta, spiramycin cannot reverse the damage. Prevention remains the best remedy.

Sonographic Signs of Perinatal Infection

ABSTRACT Evaluation of the patient at risk for fetal infection is challenging. Serologic studies may be inconclusive and often do not provide meaningful information about prognosis. Recent technologic advances have expanded the role of prenatal ultrasound in both anomaly detection and guidance for invasive diagnostic procedures. For the patient with a known or suspected fetal infection, sonographic identification of characteristic abnormalities can provide useful information for counseling and perinatal management. This article reviews the sonographic manifestations of fetal infection and the role of ultrasound in the evaluation of the fetus at risk for congenital toxoplasmosis, rubella, cytomegalovirus (CMV), and the herpes viruses (TORCH infections). How to cite this article Natsis S, Antsaklis P, Grigoriadis T, Antsaklis A. Sonographic Signs of Perinatal Infection. Donald School J Ultrasound Obstet Gynecol 2015;9(3):275-279.

Serologic Prevalence of Toxoplasma gondii in Indian Women of Child Bearing Age and Effects of Social and Environmental Factors

BackgroundSeroprevalence and incidence of toxoplasmosis in women of child bearing age has remained a contentious issue in the Indian subcontinent. Different laboratories have used different patient recruitment criteria, methods and variable results, making these data difficult to compare.AimTo map the point-prevalence and incidence of toxoplasmosis in India.Material and MethodsIn this cross-sectional study, a total of 1464 women of fertile age were recruited from 4 regions using similar recruitment plans. This included women from northern (203), southern (512), eastern (250) and western (501) regions of India. All samples were transported to a central laboratory in Delhi and tested using VIDAS technology. Their age, parity, eating habits and other demographic and clinical details were noted.ResultsMost women were in the 18–25 years age group (48.3%), followed by 26–30 years (28.2%) and 31–35 years (13.66). Few (45) women older than 35 yr. were included. Overall prevalence of anti-Toxoplasma IgG antibodies was seen in 22.40%, with significantly more in married women (25.8%) as compared to single women (4.3%). Prevalence increased steadily with age: 18.1% in the 18–25 yr. age group to 40.5% in women older than 40 yr. The prevalence was high (66%) in those who resided in mud houses. Region-wise, the highest prevalence was observed in South India (37.3%) and the lowest (8.8%) in West Indian women. This difference was highly significant (P<0.001). Prevalence was 21.2% in East India and 19.7% in North India. The IgM positivity rate ranged from 0.4% to 2.9% in four study centers.ConclusionsThis pan-India study shows a prevalence rate of 22.4% with a wide variation in four geographical regions ranging from as low as 8.8% to as high as 37.3%. The overall IgM positivity rate was 1.43%, indicating that an estimated 56,737–176,882 children per year are born in India with a possible risk of congenital toxoplasmosis.

Association between the risk of congenital toxoplasmosis and the classification of toxoplasmosis in pregnant women and prenatal treatment in Brazil, 1994–2009

The objectives of this study were to analyze the association between the classification of toxoplasmosis in the pregnant woman (TP) according to the classification of Lebech et al. and the incidence of congenital toxoplasmosis (CT), also taking into consideration prenatal treatment. A clinical cohort study of 524 children followed-up until 1 year of age was conducted. Adjusted odds ratios (OR) were estimated by logistic regression. Of 519 pregnant women, 61.3% were not classified due to the incompleteness of hospital records. Among the pregnant women classified as confirmed cases of TP (n=19), the CT risk was six times greater than in the probable/possible group. No case of CT was identified in the group of pregnant women classified as unlikely to have TP. The children with no prenatal treatment (46.2% n=242/524) presented a risk almost three times greater of CT than the treated children (OR 2.77, 95% confidence interval (CI) 1.54-4.97; p=0.001). Complete prenatal treatment was identified as a protecting factor for CT (OR 0.35, 95% CI 0.19-0.65; p=0.001). A lack or incomplete prenatal treatment was identified as an important risk factor for CT in this study. The proportions of non-classified mothers and children with no prenatal treatment reflect the need to improve prenatal care in Brazil.

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.

Identification of Potential Serodiagnostic and Subunit Vaccine Antigens by Antibody Profiling of Toxoplasmosis Cases in Turkey

Toxoplasmosis, caused by infection of the protozoan parasite Toxoplasma gondii, is associated with mild disease in healthy individuals, whereas individuals with depressed immunity may develop encephalitis, neurologic disorders, and other organ diseases. Women who develop acute toxoplasmosis during pregnancy are at risk of transmitting the infection to the fetus, which may lead to fetal damage. A diagnosis is usually confirmed by measuring IgG, or IgM where it is important to determine the onset of infection. A negative IgM result essentially excludes acute infection, whereas a positive IgM test is largely uninterpretable because IgM can persist for up to 18 months after infection. To identify antigens for improved diagnosis of acute infection, we probed protein microarrays displaying the polypeptide products of 1357 Toxoplasma exons with well-characterized sera from Turkey. The sera were classified according to conventional assays into (1) seronegative individuals with no history of T. gondii infection; (2) acute infections defined by clinical symptoms, high IgM titers, and low avidity IgG; (3) chronic/convalescent cases with high avidity IgG but persisting IgM; (iv) true chronic infections, defined by high avidity IgG and no IgM. We have identified 38 IgG target antigens and 108 IgM target antigens that can discriminate infected patients from healthy controls, one or more of which could form the basis of a 'tier-1' test to determine current or previous exposure. Of these, three IgG antigens and five IgM antigens have the potential to discriminate chronic/IgM persisting or true chronics from recent acutely infected patients (a 'tier-2' test). Our analysis of the antigens revealed several enriched features relative to the whole proteome, which include transmembrane domains, signal peptides, or predicted localization at the outer membrane. This is the first protein microarray survey of the antibody response to T. gondii, and will help in the development of improved serodiagnostics and vaccines.

Toxoplasmose et grossesse

Toxoplasmosis is the most common etiology of posterior uveitis. Toxoplasma gondii infection during pregnancy means either primary infection and risk of congenital toxoplasmosis or acute retinochoroiditis in a pregnant woman (risk of transmission, severity of injuries, therapeutics). Ingestion or manipulation of raw or undercooked meat is responsible for most contaminations (one- to two-thirds) in pregnant women. Toxoplasmosis seroprevalence is high in Europe, up to 54 % in southern European countries. Primary prevention advice is proposed to immunocompetent pregnant women who are seronegative for toxoplasmosis. The risk of transplacental transmission congenital toxoplasmosis during pregnancy is analyzed. The ocular lesions include retinochoroiditis and a number of other lesions. The departments of ophthalmology and of parasitology of Croix-Rousse University Hospital (Hospices Civils de Lyon) is currently following one of the largest cohorts of children infected with T. gondii (430 children alive in 2005). Our overall transmission rate during primary infection was 30 %. Retinochoroiditis incidence was 24 % in our prospective cohort. During follow-up, recurrences appeared in 29 % of cases. Acute toxoplasmic retinochoroiditis in pregnancy could be a risk of transplacental transmission due to potential parasitemia. Practices in cases of suspected or proved congenital infection are discussed. The antiparasitic drugs authorized during pregnancy are azithromycin and pyrimethamine. Azithromycin can be used alone but an association with pyrimethamine during the second trimester is useful in case of macular threat.

Prevalence of acute toxoplasmosis infection among 41,112 pregnant women and the mother-to-child transmission rate in a public hospital in South Brazil

Untreated acute toxoplasmosis among pregnant women can lead to serious sequelae among newborns, including neurological impairment and blindness. In Brazil, the risk of congenital toxoplasmosis (CTox) has not been fully evaluated. Our aim was to evaluate trends in acute toxoplasmosis prevalence from 1998-2005, the incidence of CTox and the rate of mother-to-child transmission (MTCT). A cross-sectional study was undertaken to dentify patients who fit the criteria for acute toxoplasmosis during pregnancy. Exposed newborns were included in a historical cohort, with a median follow-up time of 11 months, to establish definite diagnosis of CTox. Diagnoses for acute infection in pregnancy and CTox were based on European Research Network on Congenital Toxoplasmosis criteria. In 41,112 pregnant women, the prevalence of acute toxoplasmosis was 4.8/1,000 women. The birth prevalence of CTox was 0.6/1,000 newborns [95% confidence interval (CI): 0.4-0.9]. During the follow-up study, 12 additional cases were detected, increasing the CTox rate to 0.9/1,000 newborns (95% CI: 0.6-1.3). Among the 200 newborns exposed to Toxoplasma gondii,there were 37 babies presenting diagnostic criteria of CTox, leading to an MTCT rate of 18.5% (95% CI: 13.4-24.6%). The additional cases identified during follow-up reinforce the need for serological monitoring during the first year of life, even in the absence of evidence of congenital infection at birth.

Toxoplasma gondii antibody profile in HIV-infected pregnant women and the risk of congenital toxoplasmosis

The purpose of this study was to investigate the antibodies to Toxoplasma gondii in human immunodeficiency virus (HIV)-infected pregnant women and to determine the association between serological profile and the risk of congenital toxoplasmosis. The study, conducted in a public maternity ward from May 2002 to April 2005, included all HIV-infected women who delivered live infants during the 36 months, and, as a control group, all HIV-negative women that delivered live infants in the first 12 months of the study. Antibodies to T. gondii were detected in 1,624 of 2,421 HIV-negative women (67%; 95% confidence interval [CI] 65-69%) and in 121 of 168 HIV-infected patients (72%; 95% CI 65-79%). A total of 547 HIV-negative and 103 HIV-infected patients were tested at delivery and had positive T. gondii-specific IgG. In HIV-negative women, the median of the specific IgG concentration was 79 (interquartile range 38-160), and in HIV-infected patients, it was 283 (interquartile range 94-704) (P < 0.001). In the group of co-infected women, the only infant with congenital toxoplasmosis was born to a mother with acute toxoplasmosis infection acquired during pregnancy who did not have a high specific IgG concentration or a positive result for specific IgM. We concluded that high T. gondii-specific IgG values were much more frequent among HIV-infected pregnant women, but it did not translate into an increased risk of maternal-fetal transmission of toxoplasmosis.

Susceptibility to Vertical Transmission of Toxoplasma gondii is Temporally Dependent on the Preconceptional Infection in Calomys callosus

Toxoplasma gondii is an obligate intracellular parasite that causes a variety of clinical syndromes, but the infection is more severe in immunocompromised individuals and in cases of congenital toxoplasmosis. This study aimed to verify if the susceptibility to vertical transmission of Toxoplasma gondii is temporally dependent on the preconceptional infection in Calomys callosus. Twelve C. callosus females were infected with 20 cysts of T. gondii ME49 strain and divided into three groups of four animals that were mated after approximately 10days (group 1), 30days (group 2), and 50days (group 3) of infection. The animals were sacrificed from the 17th to 20th day of pregnancy, when placentas and embryos were collected for morphological and immunohistochemical studies, mouse bioassay for evaluating seroconversion and PCR for detecting parasite DNA. Serum samples from C. callosus females and mice used in bioassay were analysed for the detection of IgG antibodies to T. gondii by ELISA. Detection of T. gondii was observed by mouse bioassay and PCR in placentas and embryos from C. callosus females infected around 10days pre-conception. However, only placentas, but not embryos, from females infected around 30 and 50days pre-conception showed positivity for parasite DNA and seroconversion by mouse bioassay. In conclusion, this study model shows that vertical transmission of T. gondii may take place when maternal infection occurs within one month before conception, thus demonstrating the time of preconceptional seroconversion that rule out a risk of congenital toxoplasmosis.

Prospective study of pregnants and babies with risk of congenital toxoplasmosis in municipal district of Rio Grande do Sul

This study followed up 2,126 pregnant women cared for at SUS day-care clinics (Public Health Insurance System) of the northwest of the State of Rio Grande do Sul, Brazil. After serological screening we performed a follow up of all pregnant women and their babies. Serologic tests included: IgG, IgM, IgA and IgG avidity levels, mice inoculation and polymerase chain reaction (PCR) also placentas and umbilical materials were tested using immunoperoxidase as well as clinical evaluation. Of all the pregnant women screened, 74.5% were reactive to toxoplasmosis, and 3.6% presented IgM seropositivity. At ophthalmic evaluation ten women had ocular lesions and one infant presented eye lesions and brain calcification. The presence of anti-T.gondii specific IgM throughout the entire pregnancy did not characterize acute phase infection, for this, complementary tests were necessary. The importance is underscored for attendance of the newborn of mothers presenting serology compatible with this infection even in the absence of signs and symptoms of congenital toxoplasmosis.