Seroprevalence and sources of Toxoplasma infection among indigenous and immigrant pregnant women in Taiwan

Toxoplasma gondii exposure in Brazilian indigenous populations, their dogs, environment, and healthcare professionals

Although Toxoplasma gondii exposure has been reported in indigenous populations worldwide, a One Health approach has not been applied to date. This study concurrently assessed T. gondii exposure in indigenous populations, and their dogs, environment, and indigenous or non-indigenous healthcare professionals (HPs). Human and dog serum samples from 9 indigenous communities in Brazil were assessed by indirect immunofluorescence antibody test for anti-T. gondii antibodies. Soil samples (30 per community) were processed with PCR to amplify T. gondii DNA. Associated risk factors and seroprevalence were analyzed using logistic regression models. Human seropositivity and type of water source were assessed by generalized linear mixed model (GLMM) with binomial error distribution, and game meat consumption with chi-squared test. Overall, 225/463 (49%) indigenous persons were seropositive for anti-T. gondii antibodies. Of all the HPs, 67/168 (40%) were positive, and included 54/147 (37%) positive non-indigenous HPs. Indigenous persons more likely to be seropositive compared with non-indigenous HPs (OR: 1.63; 95% CI: 1.11-2.39). A total of 97/253 (38%) dogs were seropositive and highly associated with seropositive owners (p < 0.001). Based on univariate analysis for indigenous individuals, state location of community (p < 0.001), ethnicity (p < 0.001), consumption of game meat (p < 0.001), type of water source (p < 0.001), and educational level (p = 0.026) were associated with seropositivity. Logistic regression showed that indigenous seropositivity was associated with eating game meat (p = 0.002), drinking water from rivers (p < 0.001), and inversely proportional to the educational level. According to univariate analysis for non-indigenous HP, age (p = 0.005), frequency of visits to the indigenous populations (p < 0.001), consumption of water at the indigenous communities (p < 0.001), and ingestion of raw meat (p = 0.023) were associated with T. gondii seropositivity. Logistic regression revealed living outdoors (p = 0.042), habit of hunting (p = 0.008), and drinking river water (p = 0.007) as risk factors associated to seropositivity in dogs. In addition, indigenous communities lacking water treatment had higher seroprevalence for all groups including indigenous persons (GLMM; z = -7.153; p < 0.001), their dogs (GLMM; z = -2.405; p = 0.0162), and all HPs (GLMM; z = -2.420; p = 0.0155). Human seropositivity was associated with that of their dogs (p < 0.001). A single soil sample, out of 270 (0.37%), was positive for T. gondii by PCR. Our results indicate water source is a risk for human and dog toxoplasmosis in indigenous communities; both share similar exposure. Moreover, quality water access was shown to be crucial to prevent toxoplasmosis in both total and non-indigenous HPs who work in these indigenous communities.

Investigation of Toxoplasma infection in zoo animals using multispecies ELISA and GRA7 nested PCR

Background

Toxoplasma is an obligate intracellular protozoan that causes an important zoonotic disease with a worldwide distribution. Felids are the definitive hosts of this parasite, while virtually all warm-blooded animals, including birds, serve as intermediate hosts. Four ring-tailed lemurs (Lemur catta) in the Taipei Zoo died of acute Toxoplasma infection in June 2019. Since then, Toxoplasma has occasionally been identified in this Zoo during necropsy of dead animals and PCR of animal blood samples. Therefore, a general survey of Toxoplasma infection in animals in the Zoo seems to be needed.

Methods and results

An indirect multispecies ELISA was used for the first time to screen for Toxoplasma infection in 326 serum samples collected from 75 species of animals. The infection rate of Toxoplasma was 27% (88/326). A commercial latex agglutination (LAT) assay was used to re-examine the samples with doubtful and uncertain ELISA results (151 samples from 42 species). The infection rate increased to 36.2% (118/326), and the indirect multispecies ELISA appeared to be applicable to 31 of 75 species animals included in this study. Nested PCR assays targeting the dense granule protein 7 (GRA7) gene and B1 gene were also used to detect Toxoplasma in DNA samples extracted from 10 liver or blood specimens from 8 animals. GRA7 gene fragments were amplified from 8 samples from 7 animals, while B1 gene fragments were amplified from only 4 samples from 4 animals. From the B1 nested PCR and the sequence data of GRA7 fragments amplified from infectious specimens, the animals in the Zoo were speculated to have been infected by at least three different Toxoplasma variants.

Conclusions

According to the serological investigation, we speculated that over one-third (36.2%) of animals in Taipei Zoo presented the infection of Toxoplasma, and the indirect multispecies ELISA we used can be applied to detect Toxoplasma infection in 31 animal species included in this study. Sequence analysis revealed that at least three Toxoplasma variants were infecting the animals of Taipei Zoo.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03425-y.

Assessment of the clinical benefits of prenatal screening for toxoplasmosis in southern Taiwan

OBJECTIVE

The present study aimed to investigate the seroprevalence and risk factors for toxoplasmosis among pregnant women in southern Taiwan and to determine the clinical benefits of screening for the same.

MATERIALS AND METHODS

The current study included 458 pregnant women who received prenatal care from the first trimester at the Kaohsiung and Chiayi Chang Gung Memorial Hospitals during the time period from 2014 to 2015. Serological tests performed to detect the presence of Toxoplasma IgG and IgM antibodies. Amniocentesis was scheduled and real-time polymerase chain reaction (PCR) was employed to detect Toxoplasma DNA. Moreover, the maternal characteristics and risk factors, perinatal outcomes related to the seropositivity for Toxoplasma infection were analyzed.

RESULTS

Among the pregnant patients included in the current study, 39/458 (8.5%) were IgG+ and 2/458 (0.6%) were IgM+. The present study analyzed the maternal characteristics and risk factors, perinatal outcome pertaining to the IgG seropositive group by means of the multiple logistic regression analysis revealed a female predominance (10.8%), compared to the males (6.4%), (adjusted OR = 0.48 (95%, 0.24-0.98), P = 0.043∗). The number cases with gestational age above 37 weeks at the time of delivery was significantly lower, compared to the cases below 37 weeks (adjusted OR = 0.32 (0.12-0.94), P = 0.038∗). Among one case with low avidity cannot exclude recent infection, the amniocentesis did not show any evidence of vertical transmission.

CONCLUSION

The scenario may not warrant general screening and the results will not influence the clinical decisions. Although the present study failed to identify the maternal risk factors related to Toxoplasma infection, the results imply that health education is essential, owing to the slightly higher rate of preterm delivery in the IgG seropositive group.

Serological prevalence of toxoplasmosis in pregnant women in Luanda (Angola): Geospatial distribution and its association with socio-demographic and clinical-obstetric determinants

We report a study on toxoplasmosis in pregnant women in Luanda, Angola, determining the seroprevalence, geospatial distribution and its association with socio-economic features, dietary habits and hygiene and health conditions. Anti-Toxoplasma gondii IgG and IgM were quantified in serum samples of women attended at the Lucrecia Paim Maternity Hospital between May 2016 and August 2017. The IgG avidity test and qPCR assay were used for dating the primary infection. Data were collected by questionnaire after written consent, and spatial distribution was assessed through a Kernel Density Function. The potential risk factors associated with Toxoplasma infection were evaluated using bivariate and multivariate binomial logistic regression analysis. Anti-T. gondii antibodies were quantified in 878 pregnant women, and 346 (39.4%) samples were IgG positive, 2 (0.2%) positive for IgM and IgG, and 530 (60.4%) negative for both immunoglobulins. The longitudinal study showed that none of the seronegative women seroconverted during the survey. Regarding other infections, 226 (25.7%) were positive for hepatitis B, while 118 (13.4%) were HIV-positive. The seroprevalence of toxoplasmosis was similar in most municipalities: 43.8% in Cazenga (28 of 64); 42.5% in Viana (88 of 207); 42.3% in Cacuaco (22 of 52); and 41.1% in Luanda ((179 of 435). In contrast, the seroprevalence in municipality of Belas was lower (25.8%; 31 of 120) and bivariate and multivariate analysis has shown a lower risk for toxoplasmosis in this area (OR 0.479, CI: 0.305–0.737; OR 0.471, CI: 0.299–0.728). The multivariate analysis has shown a significant increased risk for toxoplasmosis in women in the last trimester of pregnancy (OR 1.457, CI: 1.011–2.102), suffering spontaneous abortion (OR 1.863, CI: 1.014–3.465) and having pets at home (OR 1.658, CI: 1.212–2.269). Also, women who tested positive for hepatitis B (OR 1.375, CI: 1.008–1.874) and HIV (OR 1.833, CI: 1.233–2.730) had a significant increased risk for T. gondii infection. In conclusion, our study showed that a large number of pregnant women are not immunized for toxoplasmosis and identified the risk factors for this infection in Luanda. It is crucial to establish the diagnosis of primary maternal infection as well as the diagnosis of congenital toxoplasmosis. Our results underlined the need for diagnostic and clinical follow-up of toxoplasmosis, HIV and hepatitis B during pregnancy.

Toxoplasmosis in pregnancy: a neglected bane but a serious threat in Nigeria

Toxoplasmosis is a global health threat in which occurrence in pregnant women poses grave consequences to fetal wellbeing. Studies on prenatal Toxoplasma gondii infection are generally limited in sub-Saharan African countries, including Nigeria. The risk of transmission of toxoplasmosis is very high in Nigeria due to the favourable climatic conditions and prevailing behavioural and socio-economic factors that could aid transmission. Currently, there are no systematic and organized procedures for diagnosis and treatment of maternal toxoplasmosis in Nigeria. These conditions forecast possible unabated transmission in many areas and exponential impact on associated adverse events of the disease during pregnancy. This paper highlights the importance of early diagnosis and treatment during pregnancy which may forestall subsequent development of infection in children delivered by infected mothers. Inclusion of toxoplasmosis control policy in the routine antenatal care of pregnant women is therefore strongly recommended.

Serological study on toxoplasmosis in the Haliti-Paresí community of the Utiariti indigenous territory, Campo Novo do Parecis, Mato Grosso, Brazil

Toxoplasma gondii is the etiological agent of toxoplasmosis, a widespread zoonosis that affects several homeothermic animals, including humans. This disease causes serious health problems, such that 10% of infected individuals develop clinical manifestations. Some studies on indigenous human populations have indicated variations in seroprevalence from 10.6% to 80.4% in such populations in different regions of Brazil and in other countries like Venezuela and Malaysia. To date, there have been no studies regarding the prevalence of anti-T. gondii antibodies in Haliti-Paresí Indians living in Campo Novo do Parecis, Mato Grosso, Brazil. Our objective here was to determine the frequency of occurrence of antibodies against this protozoon in nine Haliti-Paresí villages by correlating seroprevalence with locations and variables. Serodiagnoses were made using the indirect immunofluorescence antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) in the Laboratory for Toxoplasmosis and Other Protozoan Diseases of IOC/Fiocruz. It was considered that samples tested positive for T. gondii infection if IgG/IgM antibodies against this protozoon were detected through serodiagnosis using either IFAT or ELISA. Among the 293 samples analyzed, 66.9% presented anti-T. gondii IgG and 3.4% presented anti-T. gondii IgM. It was observed that there were no statistically significant differences in frequency of antibody occurrence among infected individuals, based on sex, schooling or occupation/activities. However, there were statistical differences based on age and villages. The prevalence observed in this study is in agreement with values found in other studies on indigenous populations in Latin America. Like among other such populations, the Haliti-Paresí villages are located close to forests and the individuals have domestic cats as pets, are involved in hunting and farming and consume water directly from water accumulation sources. These factors might cause exposure to T. gondii tissue cysts and oocysts.

Associated Antenatal Health Risk Factors with Incidence of Toxoplasmosis in Egyptian Pregnant Women

BACKGROUND AND OBJECTIVE

The major maternal toxoplasmosis infection during pregnancy is regularly related to trans-placental transmission to the embryo and newly-borne child. This cross-section study was performed to investigate the prevalence of toxoplasmosis among pregnant women attending antennal health centers.

MATERIALS AND METHODS

The IgM antibodies against Toxoplasma were quantitatively determined by commercially available kits, while IgG antibodies and avidity (AV) of Toxoplasma gondii-specific IgG antibodies were quantitatively determined by using of conventional ELISA.

RESULTS

The overall seroprevalence of T. gondii IgM among the investigated pregnant women was much higher than toxoplasma IgG with low IgG avidity representing acute infection with possibility of risk to the mother, embryo and newly-borne child. Results also showed that highest Toxoplasma prevalence was among pregnant women with history of intake of immunosuppressive drugs and abortion, having cats and animals in their households and in the 1st and 2nd trimesters.

CONCLUSION

The high infection prevalence of T. gondii among the Egyptian pregnant women in Giza governorate revealed the risk of premature termination of pregnancy due to exposure of T. gondii infection.

A community-based survey of Toxoplasma gondii infection among pregnant women in rural areas of Taiz governorate, Yemen: the risk of waterborne transmission

Background

Toxoplasma gondii is a zoonotic coccidian parasite causing morbidity and mortality. In Yemen, T. gondii infection has been reported among pregnant women seeking healthcare in the main cities. However, no data are available on the prevalence of T. gondii infection and its associated risk factors among pregnant women in the rural communities of the country. Thus, the present study aimed to determine the seroprevalence of T. gondii and identify its risk factors among pregnant women in the rural communities of Taiz governorate, Yemen.

Methods

A total of 359 pregnant women living in the rural communities of Taiz governorate were enrolled in this study by house-to-house visits. Data were collected using a pre-designed questionnaire, and blood samples were collected and tested for the detection of anti- T. gondii IgM and IgG antibodies by enzyme-linked immunosorbent assay.

Results

The prevalence of T. gondii infection among pregnant women in this study was 46.2% (166/359). Bivariate analysis identified the age of  ≥ 30 years (odds ratio [OR] = 1.7; 95% confidence interval [CI] = 1.09–2.65, P = 0.019) and unimproved water sources (OR = 2.2; 95% CI = 1.10–4.55, P = 0.023) as factors associated with T. gondii infection among pregnant women. The multivariable analysis, however, identified unimproved water sources as an independent risk factor (adjusted OR = 2.4; 95% CI = 1.16–5.0, P = 0.018) associated with T. gondii infection among pregnant women.

Conclusions

Pregnant women in the rural communities of Taiz, Yemen are at high risk of contracting T. gondii infection. Unimproved water sources (wells, water streams and water tanks) are significantly associated with T. gondii infection and should be considered in prevention and control strategies, especially among pregnant women.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0243-0) contains supplementary material, which is available to authorized users.

Seroprevalence and risk factors of Toxoplasma gondii infection in pregnant women following antenatal care at Mizan Aman General Hospital, Bench Maji Zone (BMZ), Ethiopia

BACKGROUND

The intracellular parasite, Toxoplasma gondii (T.gondii) is found worldwide. Infection with T. gondii during pregnancy can result in fetal and neonatal death or various congenital defects. A serological survey during pregnancy represents a valuable tool for the effective diagnosis and treatment of infected neonates. The aim of this study was to assess the sero-prevalence and risk factors of T.gondii in pregnant women following ante natal care (ANC) services at Mizan Aman General Hospital, Bench Maji zone (BMZ), Ethiopia.

METHODS

An institution based cross-sectional study was conducted enrolling a sample of 232 pregnant women attending antenatal care at Mizan Aman General Hospital during 01 December, 2014 to 18 February, 2015. Systematic random sampling technique was used to obtain the required sample. About 5 ml of blood sample was collected aseptically by using properly labeled plain tube with the necessary information. The blood samples centrifuged at 3000 rpm for 10 min to separate serum. The serum was stored at a temperature of 20 °C below zero until the serological analysis was done for the presence of anti T.gondii antibodies (i.e. Immune globulin 'M' (IgM) and Immune globulin 'G' (IgG)) using enzyme linked immunosorbent assay (ELISA). Exit interview was conducted with eligible mothers to obtain socio-demographic and behavioral data using structured questionnaires. Multivariate logistic regression modeling was employed to identify the potential predictor variables for T.gondii infection. P-value less than 5 % was considered to declare a sound significant association.

RESULTS

The response rate of the study was 100 %. The overall sero-prevalence for T.gondii infection was 85.3 % (198/232). About 191 (82.3 %) of the pregnant women were reactive only for IgG anti-bodies. While about 7 (3.0 %) of them were seropositive for both IgG and IgM anti-bodies. None of the mothers were positive for IgM anti-bodies exclusively. On multivariate logistic regression analysis, contact with cat and gardening soil were significantly associated with T.gondii infection (AOR =2.37, 95 % CI = [1.16, 3.57] and AOR = 2.49, 95 % CI = [1.53, 3.86] respectively.

CONCLUSIONS

Sero-prevalence of T. gondii antibodies for IgM was relatively high among pregnant women. Contact with cat and soil were risk factors for T.gondii case. Creating awareness on the source of infection, modes of transmission and prevention of T. gondii should be given for pregnant women. Routine screening services for T. gondii infection should be integrated with other ANC services to identify potential infections of the parasite.

Toxoplasma gondii Infection in Pregnant Women: A Seroprevalence and Case-Control Study in Eastern China

Very limited information is available concerning the epidemiology of T. gondii infection in pregnant women in eastern China. Therefore, a case-control study was conducted to estimate the seroprevalence of toxoplasmosis in this population group and to identify risk factors and possible routes of contamination. Serum samples were collected from 965 pregnant women and 965 age-matched nonpregnant control subjects in Qingdao and Weihai between October 2011 and July 2013. These were screened with enzyme linked immunoassays for the presence of anti-Toxoplasma IgG and anti-Toxoplasma IgM antibodies. 147 (15.2%) pregnant women and 167 (17.3%) control subjects were positive for anti-T. gondii IgG antibodies, while 28 (2.9%) pregnant women and 37 (3.8%) controls were positive for anti-T. gondii IgM antibodies (P = 0.256). There was no significant difference between pregnant women and nonpregnant controls with regard to the seroprevalence of either anti-T. gondii IgG or IgM antibodies. Multivariate analysis showed that T. gondii infection was associated with location, cats in home, contact with cats and dogs, and exposure to soil. The results indicated that the seroprevalence of T. gondii infection in pregnant women is high compared to most other regions of China and other East Asian countries with similar climatic conditions.

Sero-prevalence and associated risk factors of Toxoplasma gondii infection among pregnant women attending antenatal care at Felege Hiwot Referral Hospital, northwest Ethiopia

OBJECTIVE

To determine the prevalence of toxoplasmosis and to assess the possible risk factors associated with the infection among pregnant women attending antenatal care center at Felege Hiwot Referral Hospital, Bahir Dar town, northwest Ethiopia.

METHODS

A hospital based cross-sectional study was designed to determine the prevalence of toxoplasmosis among pregnant women. Three hundred eighty four serum samples were collected from November 2013 to January 2014. Data on socio-demographic and predisposing factors were collected from each study participant with simple random sampling technique. The serum samples were examined for anti-Toxoplasma gondii (T. gondii) antibodies using latex agglutination test.

RESULTS

The overall seroprevalence of T. gondii among the pregnant women was 18.5%. All of T. gondii positive cases found to be positive only for IgG antibody. Significant association was observed between seroprevalence and presence of domestic cats [AOR = 2.85, 95% CI: 1.66-4.90, P = 0.000], consumption of raw or undercooked meat [AOR = 1.98, 95% CI: 1.15-2.43, P = 0.014] and history of abortion [AOR = 2.47, 95% CI: 1.40-4.34, P = 0.002]. No significant association was observed between seroprevalence and socio-demographic characters, gestational age, gravidity, consumption of raw vegetable, and blood transfusion.

CONCLUSIONS

The seroprevalence of toxoplasmosis among pregnant women in Bahir Dar town was relatively high. Presence of domestic cats at home and consumption of raw or undercooked meat were identified as main risk factors for T. gondii infection. Therefore, health education towards avoiding eating raw or undercooked meat and avoiding contact with cats are recommended for prevention of miscarriage or defects during pregnancy.

Seroprevalence of anti-Toxoplasma IgG and IgM among individuals who were referred to medical laboratories in Mazandaran province, northern Iran

Toxoplasma gondii (T. gondii) is a protozoan parasite that can cause toxoplasmosis in humans. However, there is no current data regarding Toxoplasma infection among individuals who were referred to medical laboratories in Mazandaran province (northern Iran). Therefore, we performed a population-based study of Toxoplasma seroprevalence in this region. A total of 1832 sera samples (from 654 men and 1178 women) were collected from people who were referred to medical laboratories in different cities throughout Mazandaran province between March and July 2012. The serum titers of anti-T. gondii IgG and IgM were measured using enzyme-linked immunosorbent assays. The seroprevalence of anti-Toxoplasma IgG was 55.5%; and 14.4% of the positive samples were seropositive for anti-Toxoplasma IgM. The highest seroprevalence was observed among people who were >50 years old (90.6%), and the lowest seroprevalence was observed among children who were 0-9 years old (9.4%; P<0.001). There was no significant difference in the seroprevalences for each sex in the study population. However, a regional sex-specific difference in seroprevalence was observed between men (54.1%) and women (70.6%; P=0.003) in the western cities of Mazandaran. As the seroprevalence of T. gondii in western and eastern Mazandaran was higher than that in the central cities, there is a need to evaluate the nature of the infection chain in these areas.

Seroprevalence of Toxoplasma gondii in women who have aborted in comparison with the women with normal delivery in Ahvaz, southwest of Iran

Toxoplasma gondii is an obligate intracellular protozoan parasite causing toxoplasmosis in animals and humans. Primary maternal infection with toxoplasmosis during pregnancy is frequently associated with transplacental transmission to the fetus. However it is not certain whether Toxoplasma infection can cause recurrent abortion. The aim of this study was to determine the relationship between Toxoplasma infection and abortion via detection of anti-Toxoplasma gondii antibodies in sera of women with obstetrical problems and compare the results with control group consisting of women with history of normal delivery. Sera from 130 women with abortion and sera of 130 women with normal delivery were tested for IgG and IgM anti-Toxoplasma gondii antibodies by ELISA method. The present study revealed 24.6% of the samples with abortion and 21.5% of the samples with normal delivery were positive for IgG antibodies. However, statistical analysis indicated no significant differences (P > 0.05). In addition, IgM antibody was detected in one woman who had aborted but not in women with normal childbirth. This study showed no significant difference between the case and control groups in IgG anti-Toxoplasma antibody but detected one sample with IgM antibodies in woman with abortion during the first trimester of pregnancy. In order to determine the relationship between Toxoplasma infection and abortion, anti-Toxoplasma IgG avidity and PCR to discriminate between recent and prior infections are recommended.

Seroepidemiology of Toxoplasma gondii amongst Pregnant Women in Jazan Province, Saudi Arabia

Background. Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite of worldwide distribution. There is limited information about the seroprevalence of toxoplasmosis in the southern area of Saudi Arabia. The current study was carried out to determine the prevalence of T. gondii in pregnant women in Jazan province. Materials and Methods. The study was conducted between January and June 2013 and included 195 pregnant women, data on sociodemographic and predisposing factors were collected from each participant. Venous blood samples were collected following standard operating procedures. Serological analysis for latent toxoplasmosis (levels of IgG) and active toxoplasmosis (IgM) was done using Enzyme Linked Immunosorbent Assay (ELISA). Results. The overall seroprevalence of T. gondii in the study area was 24.1%. The seroprevalence of anti-Toxoplasma IgG was 20% (39 out of 195), whereas IgM seropositivity was 6.2% (12 out of 195). Only 4 pregnant women tested positive for both IgG and IgM. The highest IgG and IgM seroprevalence was among the study participants aged 35 to 39 years (13.5% and 35.1%, resp.). The seropositivity rate of T. gondii-specific antibodies was higher among pregnant women from the urban areas than those from rural communities (7.4% versus 0% and 21% versus 15.4% for IgM and IgG, resp.). Conclusions. The seroprevalence of T. gondii was high in pregnant woman in Jazan. The prevalence of toxoplasmosis increases with increase of age. Awareness health education program in Jazan needs to be maintained and developed to targeted pregnant women.

Autophagy activated by Toxoplasma gondii infection in turn facilitates Toxoplasma gondii proliferation

Autophagy was found to play an antimicrobial or antiparasitic role in the activation of host cells to defend against intracellular pathogens, at the same time, pathogens could compete with host cell and take advantage of autophagy to provide access for its proliferation, but there are few articles for studying the outcome of this competition between host cell and pathogens. Therefore, the aim of our study was to investigate the relationship between autophagy activated by Toxoplasma gondii (T. gondii) and proliferation of T. gondii affected by autophagy in vitro. Firstly, human embryonic fibroblasts (HEF) cells were infected with T. gondii for different times. The monodansylcadaverine (MDC) staining, acridine orange (AO) staining, punctuate GFP-LC3 distribution, and transmission electron microscopy (TEM) assays were conducted, and the results were consistent in showing that gondii infection could induce autophagy. Secondly, HEF cells were infected with T. gondii and treated with autophagy inhibitor bafilomycin A1 or inducer lithium chloride for different times. Giemsa staining was conducted, and the results exhibited that T. gondii infection-induced autophagy could in turn promote T. gondii proliferation. Simultaneously, the results of Giemsa staining also revealed that autophagy inhibitor could reduce the number of each cell infected with T. gondii and inhibit T. gondii proliferation. In contrast, autophagy inducer could increase the number of each cell infected with T. gondii and encourage T. gondii proliferation. Therefore, our study suggests that T. gondii infection could activate autophagy, and this autophagy could in turn facilitate T. gondii proliferation in HEF cells for limiting nutrients.

Risk factors for acute Toxoplasma gondii diseases in Taiwan: a population-based case-control study

Although human toxoplasmosis is a notifiable disease in Taiwan since 2007, little is known about its risk factors. This study aimed to investigate the risk factors for acute Toxoplasma gondii diseases in Taiwan. We conducted a nationwide population-based case-control study. Cases of acute human toxoplasmosis notified to the Taiwan Centers for Diseases Control (Taipei, Taiwan) during 2008–2013 were compared with controls that were randomly selected from healthy T. gondii-seronegative blood donors who participated in a nationwide T. gondii seroepidemiologic study during 2009–2010. Cases and controls were matched according to age, gender and residency at an 1∶8 ratio. Structured questionnaires were used to gather information regarding risk factors. A total of 30 laboratory-confirmed acute T. gondii disease cases and 224 controls were enrolled. The most common clinical manifestation of the cases was flu-like symptoms (n = 20), followed by central nervous system disease (n = 4), ocular diseases (n = 3), abortion (n = 2), and congenital infection (n = 1). Multivariate conditional logistic regression showed that raw clam consumption (adjusted odds ratio [OR] = 3.7; 95% confidence interval [CI] = 1.4–9.9) and having a cat in the household (adjusted OR = 2.9; 95% CI = 1.1–7.9) were two independent risk factors for acute T. gondii disease. We conclude that raw shellfish consumption and domestic cat exposure were risk factors for acquiring acute T. gondii diseases in Taiwan. This finding may guide future research and control policies.

Sero-prevalence and factors associated with Toxoplasma gondii infection among pregnant women attending antenatal care in Mwanza, Tanzania

BACKGROUND

Serological screening of pregnant women for Toxoplasma gondii-specific antibodies is not practiced as an antenatal care in Tanzania; and there is a limited data about sero-prevalence of T. gondii infection in developing countries. We therefore conducted this study to determine the sero-prevalence and factors associated with T. gondii infection among pregnant women attending antenatal care clinics in Mwanza, Tanzania.

METHODS

Between 1st November 2012 and 31st May 2013 a total of 350 pregnant women attending antenatal care clinics in Mwanza were enrolled and screened for IgG and IgM antibodies against T. gondii using the ELISA technique.

RESULTS

Of 350 pregnant women, 108 (30.9%) were sero-positive for T. gondii-specific antibodies. The risk of contracting T. gondii infection increases by 7% with each yearly increase in a woman's age (OR=1.07, 95% CI: 1.02 - 1.11, p=0.002). The sero-positivity rate of T. gondii-specific antibodies was higher among pregnant women from the urban than those from rural communities (41.5% versus 22.0%); [OR=2.2, 95% CI; 1.4 - 3.7, p=0.001]. Likewise employed/business women were more likely to get T. gondii infection than peasants (40.0% versus 25.9%) [OR=1.9, 95% CI: 1.2 - 3.0, p=0.006].

CONCLUSIONS

Sero-prevalence of T. gondii-specific antibodies is high among pregnant women in Mwanza with a significant proportion of women at risk of contracting primary T. gondii infections. Screening of T. gondii infections during antenatal care should be considered in Tanzania as the main strategy to minimize congenital toxoplasmosis.

Seroprevalence and risk factors of toxoplasmosis in cattle from extensive and semi-intensive rearing systems at Zona da Mata, Minas Gerais state, Southern Brazil

BACKGROUND

Concerning the infection of humans by T. gondii, limited efforts have been directed to the elucidation of the role of horizontal transmission between hosts. One of the main routes of transmission from animals to humans occurs through the ingestion of raw or insufficiently cooked meat. However, even though the detection of T. gondii in meat constitutes an important short-term measure, control strategies can only be accomplished by a deeper understanding of the epidemiology of toxoplasmosis. The present study aimed to investigate the seroprevalence of toxoplasmosis in cattle from Zona da Mata, Minas Gerais, Brazil, and to identify associated risk factors, through an epidemiological investigation.

METHODS

The animals studied (Bos indicus, breed Nelore or Gir) were reared in the Zona da Mata micro-region and killed at a commercial slaughterhouse at Juiz de Fora, Minas Gerais state. The animals came from 53 cattle farms with extensive (predominantly pasture feeding management) or semi-intensive (food management based on grazing, salt mineral and feed supplementation) rearing systems. Blood samples were collected from 1200 animals, and assigned to Indirect Fluorescent Antibody Test.

RESULTS

When analyzing IgG anti-T.gondii we found an overall seroprevalence of 2.68%. In Brazil prevalences vary from 1.03% to 60%. Although in the present study, the seroprevalence per animal is considered low compared to those observed in other studies, we found out that of the 53 farms analyzed, 17 (34.69%) had one or more positive cattle. It is a considerable percentage, suggesting that the infection is well distributed through the Zona da Mata region. The results of the epidemiological investigation showed that the main risk factors of Toxoplasma gondii infection are related to animal management and to the definive host. There was a relationship between the number of seropositive cattle and the presence and number of resident cats, presence and number of stray cats, presence of cats walking freely, rat control by using cats and feed storage.

CONCLUSION

These results may contribute to the development of preventive strategies in Brazil and other developing countries were extensive and semi-intensive cattle rearing systems are very widespread and the efforts to control this important zoonotic disease have attained little success.

The impact of the waterborne transmission of Toxoplasma gondii and analysis efforts for water detection: an overview and update

The ubiquitous protozoa Toxoplasma gondii is now the subject of renewed interest, due to the spread of oocysts via water causing waterborne outbreaks of toxoplasmosis in different parts of the world. This overview discusses the different methods for detection of Toxoplasma in drinking and environmental water. It includes a combination of conventional and molecular tools for effective oocyst recovery and detection in water sources as well as factors hindering the detection of this parasite and shedding light on a promising new molecular assay for the diagnosis of Toxoplasma in environmental samples. Hopefully, this attempt will facilitate future approaches for better recovery, concentration, and detection of Toxoplasma oocysts in environmental waters.

Seroprevalence of Toxoplasma gondii and associated risk factors among pregnant women in Jimma town, Southwestern Ethiopia

Background

Toxoplasmosis is a common parasitic infection caused by an obligate intracellular protozoan, Toxoplasma gondii. If primary toxoplasmosis occurs during pregnancy about one third of the cases could lead to congenital toxoplasmosis, with subsequent pathological effects. This study aimed at determining the seroprevalence of T. gondii among pregnant women in Jimma town, Southwest Ethiopia.

Methods

A community based cross-sectional study was conducted to assess the seroprevalence and associated factors in pregnant women from August to September, 2011. A total of 201 study participants were included in this study. Data on socio-demographic and predisposing factors were collected from each study participant. Moreover, venous blood specimens were collected following Standard Operating Procedures. All the collected specimens were tested for IgM and IgG anti-T. gondii antibodies by enzyme-linked immunosorbent assay (ELISA).

Results

The overall seroprevalence of T. gondii in the study area was 83.6%. One hundred and sixty three (81.1%) of the pregnant women were IgG seropositive, five (2.5%) were IgM seropositive. Three of the 5 pregnant women were positive for both IgG and IgM. Presence of domestic cat at home showed significant association with anti-T. gondii seropositivity (OR = 5.82, 95% CI: 1.61- 20.99; p < 0.05).

Conclusion

The seroprevalence of T. gondii antibodies was high among the pregnant women. Pregnant women having domestic cat at their home were at higher risk of T. gondii infection. Hence, health education and awareness on the disease and its transmission to women of reproductive age group in general and pregnant women in particular should be created during antenatal follow up to reduce the risk of T. gondii infection in pregnant women.

Prevalence of Toxoplasma gondii infection in antenatal population in Menoufia governorate, Egypt

Knowledge of the prevalence of Toxoplasma gondii infection in pregnant women would be a valuable approach for planning appropriate preventive strategies. However, no enough data currently exist as to the magnitude of T. gondii infection among pregnant women in Egypt. In view of paucity of reports on this issue, the current cross-sectional study aimed to determine the rate of T. gondii infection and maternal-fetal transmission in antenatal population in Menoufia governorate, Egypt. Out of 323 pregnant women who were screened for Toxoplasma-specific IgG and IgM antibodies with ELFA, 218 samples were IgG seropositive, of which, 9 samples were IgM seropositive. Therefore, seropositivity rates of 67.5% (95% CI: 62.39%, 72.61%), and 2.8% (95% CI: 1%, 4.6%) for IgG and IgM, respectively were found. Analysis of serological patterns revealed that a large proportion of subjects were immune to Toxoplasma infection (IgG+/IgM-), as prevalence of chronic infection was 64.7% (209 cases), and 32.5% of cases were susceptible to primary infection (IgG-/IgM-). Meanwhile, the rate of probable acute Toxoplasma infection (IgG+/IgM+) was 2.8%, with one case (0.3%) confirmed for recent infection, as she had low avidity index with positive amniotic fluid analysis with both PCR and mouse inoculation. Significant relations were seen between Toxoplasma-specific IgG and knowledge about transmission modes, consumption of milk/milk products and unwashed raw vegetable/fruit, hand hygiene, contact with soil and farm animals. In conclusion, we reported high prevalence for T. gondii infection among antenatal population in Menoufia governorate. Thus, the susceptibility for toxoplasmosis is relatively low. Sources of infection revealed herein might represent potential threats for primary infection in seronegative women. Accordingly, there is urgent need for implementation of health education programs as an appropriate approach for prevention.

Epidemiology and aetiology of maternal parasitic infections in low- and middle-income countries

BACKGROUND

There have been very few systematic reviews looking at maternal infections in the developing world, even though cutting maternal mortality by three quarters is United Nation's Millennium Development Goal number five. This systematic review has two aims. The first is to present the prevalence of parasitic infections in the developing world over the last 30 years and the second is to evaluate the quality and distribution of research in this field.

METHODS

A systematic review of Medline, EMBASE and Global Health databases was undertaken using pre-determined search criteria. Three levels of quality criteria for exclusion of inadequate studies identified 115 out of initial 8580 titles. The data were extracted for 5 domains: worldwide pathogen prevalence, year of study, study setting, sample size and diagnostic test for each pathogen.

RESULTS

The initial search retrieved 8580 results. From these titles, 43 studies on malaria, 12 studies on helminths, 49 studies on Toxoplasma gondii, 7 studies on Chagas disease, 5 studies on Trichomonas, 1 leishmaniasis study and 1 study on trichinellosis were extracted for analysis. High prevalence of malaria was found in Gabon (up to 57%) India (55%), Cameroon (50%), Yemen (55%), Nigeria (up to 64%) and Ghana (54%). High prevalence of hookworm infections was found in Nepal at 78.8% and high values of Ascaris lumbricoides were found in Nepal, (56.2%), Kenya (52.3%) and Gabon (45.5%). High levels of Schistosoma mansoni were found in Zimbabwe (50%) and Tanzania (63.5%). The prevalence of active Toxoplasma gondii infection was found to be highest in India (27.7%).

CONCLUSION

This study highlights the large burden of maternal parasitic infections globally. It may serve as a useful starting point for health policy development and research prioritization in this area.

Seroprevalence and sources of toxoplasmosis among Orang Asli (indigenous) communities in Peninsular Malaysia

This study aims to evaluate the current seroprevalence of toxoplasmosis among indigenous communities in Peninsular Malaysia and relate its association with epidemiological data. Overall seroprevalence of Toxoplasma gondii was 37.0% with 31.0% immunoglobulin (Ig) G, 1.8% IgM, and 4.2% seropositivity for both anti-Toxoplasma antibodies. Multivariate analysis showed that age above 12 years (odds ratio [OR] = 2.70, 95% confidence interval [CI] = 1.75-4.04, P < 0.001), using untreated river and mountain water supplies (OR = 1.50, 95% CI = 1.01-2.40, P = 0.050), and close proximity with cats (OR = 1.40, 95% CI = 1.10-1.76, P = 0.010) were factors associated with toxoplasmosis. Given the high seroprevalence of toxoplasmosis among these communities who live in poor socioeconomic conditions, a comprehensive health surveillance program and screening should be initiated among women of childbearing age and pregnant women during the antenatal period for early diagnosis and treatment. The role of domestic cats and environmental contamination with oocyst in soil and water has to be highlighted and addressed in future prevention strategies for these communities.

Toxoplasma gondii infection in pregnant women in China

Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is one of the most common parasitic infections in humans. Primary infection in pregnant women can be transmitted to the fetus leading to miscarriage or congenital toxoplasmosis. Carefully designed nationwide seroprevalence surveys and case-control studies of risk factors conducted primarily in Europe and America, have shaped our view of the global status of maternal and congenital infection, directing approaches to disease prevention. However, despite encompassing 1 in 5 of the world's population, information is limited on the status of toxoplasmosis in China, partly due to the linguistic inaccessibility of the Chinese literature to the global scientific community. By selection and analysis of studies and data, reported within the last 2 decades in China, this review summarizes and renders accessible a large body of Chinese and other literature and aims to estimate the seroprevalence in Chinese pregnant women. It also reviews the prevalence trends, risk factors, and clinical manifestations. The key findings are (1) the majority of studies show that the overall seroprevalence in Chinese pregnant women is less than 10%, considerably lower than a recently published global analysis; and (2) the few available appropriate studies on maternal acute infection suggested an incidence of 0·3% which is broadly comparable to studies from other countries.

Toxoplasmosis-serological evidence and associated risk factors among pregnant women in southern Thailand

Toxoplasma gondii is an important parasite in pregnant women. This case-controlled study assessed the seroprevalence of toxoplasmosis in 640 pregnant women in southern Thailand and identified their associated risk factors. The overall seroprevalence of toxoplasmosis was 181 (28.3%). Of this, 138 (21.6%) were positive for only anti-Toxoplasma immunoglobulin G (IgG) antibody, 43 (6.7%) were positive for both IgG and IgM antibodies, and none were positive for IgM antibody. Multivariate analysis revealed that increasing age (adjusted odds ratio [OR] = 1.64, 95% confidence interval [CI] = 1.01-2.67), living outside Songkhla province (adjusted OR = 1.56, 95% CI = 1.08-2.24), parity (adjusted OR = 1.65, 95% CI = 1.01-2.68), contact with cats (adjusted OR = 1.70, 95% CI = 1.20-2.43), and drinking of unclean water (adjusted OR = 1.70, 95% CI = 1.08-2.68) were factors associated with Toxoplasma seroprevalence. On the basis of the results obtained, a health surveillance program should be initiated as a primary preventive measure for congenital toxoplasmosis and focus on educating women of the child-bearing age group to avoid contact with cats and to strictly practice personal hygiene.

Seroprevalence of Toxoplasma gondii infection among immigrant and native pregnant women in Eastern Spain

In European countries, toxoplasma antenatal screening is recommended to prevent toxoplasmosis. The seroprevalence of these infections in immigrants can be different than in native population. From February 2006 to June 2010, a cross-sectional study was carried out in all pregnant women attended at a reference unit in Elche, Spain. An enzyme immunoassay was used for detection of IgG antibodies against Toxoplasma gondii. For each immigrant woman, one Spanish pregnant woman of the same age cared for in the same day was recruited (Spanish control group). A total of 1,627 migrant pregnant women participated in this study. The adherence to screening among migrants was 91.9% (95% CI, 90.5-93.1%), similar than that found in Spaniards (92.2%; 95% CI, 90.8-93-4%). Among migrant women, 619 were positive for IgG anti-T. gondii antibodies (41.4%; 95% CI, 38.9-43.9%), compared with 12.0% (95% CI, 10.5-13.8%) among Spaniards (odds ratio (OR), 5.2 (95% CI, 4.3-6.3). Seroprevalence in pregnant women from Latin America, northern Africa, Eastern Europe, Africa Sub-Saharan and Western Europe was higher than in the Spanish control group (OR, 5.4, 5.8, 6.5, 5.4, and 2.4, respectively; p < 0.001). No Asian pregnant woman was immune. Seroprevalence increased with increasing age in migrant pregnant women: 15-25 years, 38.2%; 26-35 years, 40.7%; and 36-45 years, 52.8%. The seroprevalence of T. gondii infection in migrant pregnant women living in Spain was higher than in the native population. However, no cases were found in Asian immigrants, highlighting the importance of primary prevention of this infection in pregnant women coming from that geographic region.

Seroprevalence and incidence of Toxoplasma gondii among apparently healthy and visually or hearing disabled children in Taiz City, Yemen

This cross sectional study was conducted in the city of Taiz, Yemen, during the period from August 2006 to August 2007 in order to investigate the seroprevalence and incidence of toxoplasmosis among apparently healthy children (AHC) and visually and/or hearing disabled children (DC). The seroprevalence was 16.0% among AHC compared to 32.5% among DC. The effect of gender was clear as the seroprevalence rate was significantly higher among females (18.3 and 43.8% for AHC and DC, respectively) than males (13.8 and 25% for AHC and DC, respectively). The seroprevalence was proportionally increased with the age, and the highest rates (20.9 and 53.0%) were reported among the oldest age group (> 10-14 years) for AHC and DC groups, respectively. The incidence rate was also higher (4.2%) in DC group compared to AHC group (2.4%) during 1 year period. These data indicate that the seroprevalence and incidence of toxoplasmosis are significantly higher in DC group than those of AHC group. We need to check further relationship between toxoplasmosis and visual and/or hearing disability.

What do we know about risk factors for infection in humans with Toxoplasma gondii and how can we prevent infections?

Fourteen case-control studies evaluating the importance of different risk factors for infection of humans with Toxoplasma gondii were identified. Surprisingly, up to two-thirds of infections could not be explained by risk factors such as consuming raw or undercooked meat or poor kitchen hygiene. Few studies reported population attributable risk, and when reported, it was low. Protocols including questionnaires used for collecting data, age and socio-economic groups studied, and sample sizes varied among studies. There is a need for carefully planned, case-control studies to identify sources of infection with T. gondii in humans. New risk factors, such as the manufacture of organic meat, and possible ways to sterilize meat to inactivate T. gondii tissue cysts are discussed.

Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis

Toxoplasma gondii's importance for humans refers mainly to primary infection during pregnancy, resulting in abortion/stillbirth or congenital toxoplasmosis. The authors sought to evaluate the current global status of T. gondii seroprevalence and its correlations with risk factors, environmental and socioeconomic parameters. Literature published during the last decade on toxoplasmosis seroprevalence, in women who were pregnant or of childbearing age, was retrieved. A total of 99 studies were eligible; a further 36 studies offered seroprevalence data from regions/countries for which no data on pregnancy/childbearing age were available. Foci of high prevalence exist in Latin America, parts of Eastern/Central Europe, the Middle East, parts of south-east Asia and Africa. Regional seroprevalence variations relate to individual subpopulations' religious and socioeconomic practices. A trend towards lower seroprevalence is observed in many European countries and the United States of America (USA). There is no obvious climate-related gradient, excluding North and Latin America. Immigration has affected local prevalence in certain countries. We further sought to recognise specific risk factors related to seropositivity; however, such risk factors are not reported systematically. Population awareness may affect recognition of said risks. Global toxoplasmosis seroprevalence is continuingly evolving, subject to regional socioeconomic parameters and population habits. Awareness of these seroprevalence trends, particularly in the case of women of childbearing age, may allow proper public health policies to be enforced, targeting in particular seronegative women of childbearing age in high seroprevalence areas.

Waterborne toxoplasmosis--recent developments

Humans become infected with Toxoplasma gondii mainly by ingesting uncooked meat containing viable tissue cysts or by ingesting food or water contaminated with oocysts from the feces of infected cats. Circumstantial evidence suggests that oocyst-induced infections in humans are clinically more severe than tissue cyst-acquired infections. Until recently, waterborne transmission of T. gondii was considered uncommon, but a large human outbreak linked to contamination of a municipal water reservoir in Canada by wild felids and the widespread infection of marine mammals in the USA provided reasons to question this view. The present paper examines the possible importance of T. gondii transmission by water.

Management of Toxoplasma gondii infection during pregnancy

Acute infection with Toxoplasma gondii during pregnancy and its potentially tragic outcome for the fetus and newborn continue to occur in the United States, as well as worldwide, despite the fact that it can be prevented. The infection can be acquired through ingestion of infected, undercooked meat or contaminated food or water. Transmission to the fetus occurs almost solely in women who acquire their primary infection during gestation and can result in visual and hearing loss, mental and psychomotor retardation, seizures, hematological abnormalities, hepatosplenomegaly, or death. Systematic education and serological screening of pregnant women are the most reliable and currently available strategies for the prevention, diagnosis, and early treatment of the infection in the offspring; this is largely because toxoplasmosis in pregnant women most often goes unrecognized. Treatment of the infection in the fetus and infant during the first year of life has been demonstrated to significantly improve the clinical outcome.