Toxoplasma gondii seroprevalence among pregnant women attending antenatal clinic in Northern Tanzania

Global seroprevalence of Toxoplasma gondii in pregnant women: a systematic review and meta-analysis

BACKGROUND

Toxoplasmosis in pregnancy is associated with serious and irreversible maternal and fetal detrimental consequences. Also, different seroprevalence of Toxoplasma gondii in pregnancy is reported in many countries. The present systematic review and meta-analysis study aimed to determine the global seroprevalence of Toxoplasma gondii in pregnant women.

METHODS

This study was conducted based on the PRISMA 2020 criteria. Initial searching was conducted using MeSH (Medical Subject Headings)-based keywords with no time limitation (by August 1, 2024). Collected papers were transferred to Citation Management Software (EndNote). Duplicate studies were merged and primary and secondary screenings were applied based on the inclusion/exclusion criteria. Validation was considered to find high-quality assessments. Finally, eligible extractable papers were enrolled for data collection. Data was analyzed using Comprehensive Meta-Analysis software (v.2) The random effects model was used in case of I2 index above 50%.In order to investigate the factors affecting the heterogeneity of studies, meta-regression tests were used to examine factors such as sample size and year of study.

RESULTS

One hundred thirty-eight eligible studies with a total sample size of 135,098 pregnant women individuals were selected for data extraction and analysis. The heterogeneity index was found high (I2:98.9) and the random effect model was used for analysis. The egger test revealed the absence of publication bias in collected studies (p:0.088). Thus, the global seroprevalence of Toxoplasma gondii in pregnant women was reported at 36.6% (95%CI:33.7-39.6). the highest prevalence reported based on meta-analysis was reported in South America with 52.8% (95% CI:46.6-59), while only 15 studies were reviewed in this continent, most of which were in Brazil. Therefore, after the continent, the highest prevalence reported was reported in Africa with 46.8% (95% CI:39.5-54.3). Also, the lowest prevalence reported based on meta-analysis was in North America with 19.7% (95% CI:8.4-39.6) and Europe with 24.6% (95% CI:17.8-32.9).

CONCLUSION

This study revealed a high level of seroprevalence of Toxoplasma gondii in pregnant women worldwide. This value mostly depends on the individual's age, lifestyle, and disease awareness regarding toxoplasmosis in pregnant women. Thus, public awareness, along with comprehensive health programs regarding the detrimental effects of toxoplasmosis in pregnant women, seems necessary for prevention or even early diagnosis of toxoplasmosis in pregnant women.

Knowledge Gaps and Educational Opportunities in Congenital Toxoplasmosis: A Narrative Review of Brazilian and Global Perspectives

Congenital toxoplasmosis is a parasitic disease caused by the transmission of the protozoan Toxoplasma gondii during pregnancy that can potentially cause severe consequences for the fetus or neonates. The disease disproportionately impacts the global population and is generally correlated with the Human Development Index. Despite its prevalence, there are knowledge gaps among pregnant women and healthcare providers regarding the prevention, diagnosis, and treatment of this condition. This narrative review aimed to examine the current state of knowledge of toxoplasmosis among both groups, with a focus on exploring the Brazilian and global perspectives and highlighting opportunities for enhancing education and communication. A search was conducted across five databases, and 60 studies were selected (23 in Brazil and 37 worldwide). Quantitative analysis revealed that general knowledge of toxoplasmosis among pregnant women is notably poor, with 66% of Brazilian women and 72% of women worldwide lacking sufficient understanding. Among those with some knowledge, the most recognized association is with cats (46% in Brazil and 38% worldwide), followed by raw or undercooked meat (27% in Brazil and 25% worldwide), and improperly sanitized vegetables or water (15% in Brazil and 21% worldwide). Similarly, gaps in knowledge were found among healthcare providers. Difficulty with IgG avidity test interpretation is higher in Brazil (43%) compared to worldwide (18%). The most recognized association is with cats (66% in Brazil and 74% worldwide), followed by raw or undercooked meat (49% in Brazil and 70% worldwide), and improperly sanitized vegetables or water (31% in Brazil and 32% worldwide). These findings emphasize the need for tailored local and global public health educational initiatives to enhance knowledge of toxoplasmosis among pregnant women and healthcare providers.

Toxoplasma gondii seroprevalence among pregnant women in Africa: A systematic review and meta-analysis

BACKGROUND

Toxoplasmosis is a serious endemic zoonotic disease caused by the protozoan parasite Toxoplasma gondii. Toxoplasma infection during pregnancy can result in congenital transmission and serious fetal and neonatal complications. This systematic review and meta-analysis aimed to assess the pooled seroprevalence of T. gondii infection and its determinants among pregnant women in African countries.

METHODS

All articles reporting the seroprevalence of toxoplasmosis among pregnant women in African countries and published from 2010 to 2023 were searched using various databases. The pooled prevalence of toxoplasmosis was calculated using a random-effect model. The variation between the included studies was assessed using a funnel plot and I2 heterogeneity statistics. To identify the sources of heterogeneity, sub-group analysis was further conducted by country, diagnostic method, and sub-African region. The association of prevalence rates with the socio-economic level and geoclimatic parameters was also explored.

RESULTS

In total, 29,383 pregnant women from 60 articles were included for analysis. The pooled T. gondii seroprevalence was 42.89% with high heterogeneity (I2 = 99.4%, P < 0.001). Sub-group analysis revealed variation by country (ranging from 2.62% in Namibia to 80.28% in Congo), diagnostic method used (from 8.66% in studies using a rapid diagnostic test to 55.69% in those using an agglutination test), and sub-African region (from 4.14% in regions of Southern Africa to 53.96 in Central Africa). Cat ownership (OR = 1.58) and the consumption of raw meat (OR = 1.50) and raw vegetables (OR = 1.48) had a statistically significant combined effect on T. gondii seroprevalence. No association was found between T. gondii prevalence and the level of income of the country or geoclimatic parameters.

CONCLUSION

The prevalence of toxoplasmosis infection among pregnant women in Africa is high, particularly in Central and Eastern Africa. The determinants of prevalence are multifactorial. Therefore, efforts should be made to increase the awareness of women concerning the risk factors for toxoplasmosis.

Seroprevalence and risk factors for Toxoplasma gondii infection among pregnant women at Debre Markos Referral Hospital, northwest Ethiopia

BACKGROUND

To assess the seroprevalence and risk factors of Toxoplasma gondii infection in pregnant women at the Debre Markos Referral Hospital, northwest Ethiopia.

METHODS

A facility-based cross-sectional study was undertaken among pregnant women from March 2020 to May 2021. Sociodemographic and clinical data were collected from randomly selected participants. Five millilitres of blood was collected and an enzyme-linked immunosorbent assay kit was used to test for T. gondii immunoglobulin G (IgG) antibodies. A logistic regression model was computed to identify the risk factors. The adjusted odds ratio (aOR) was estimated along with the 95% confidence interval (CI). A statistically significant association was defined as p<0.05.

RESULTS

T. gondii IgG antibody positivity was found in 38.8% (n=132) of 340 pregnant women. Contact with cats (AOR 2.5 [95% CI 1.5 to 4.2]), eating raw/undercooked meat (AOR 5.7 [95% CI 3.2 to 10.3]), consuming unwashed vegetables (AOR 4.1 [95% CI 2.1 to 8.0]), a history of abortion (AOR 1.9 [95% CI 1.1 to 3.3]) and drinking water sources (AOR 2.5 [95% CI 1.2 to 5.2]) demonstrated a statistically significant association with T. gondii infection.

CONCLUSIONS

Toxoplasmosis was found to be fairly common in pregnant mothers. Proper cat excreta disposal, not eating raw/undercooked meat, maintaining hand cleanliness and following environmental sanitation protocols could be important to decrease T. gondii infection.

The synergetic potential of Lactobacillus delbrueckii and Lactobacillus fermentum probiotics in alleviating the outcome of acute toxoplasmosis in mice

Toxoplasmosis is an immunologically complex disease, particularly in immunocompromised patients. Although there are several therapeutic regimens for such disease, the majority of them have many drawbacks. Therefore, it is of utmost importance to improve the current regimen in an effort to achieve a well-tolerated therapy while also enhancing the host immune response. Famous for their immunomodulatory effect, Lactobacillus delbrueckii and Lactobacillus fermentum probiotics were chosen to be evaluated in this study as an adjuvant therapy against the virulent RH Toxoplasma gondii (T. gondii) strain. Experimental mice were divided into control and treated groups. The control group was further subdivided into two groups: group I: 10 uninfected mice and group II: 20 infected untreated mice. The treated experimental group was subdivided into three groups (20 mice each); group III: sulfamethoxazole-trimethoprim (SMZ-TMP) treated, group IV: probiotics treated, and group V: SMZ-TMP combined with probiotics. The results obtained revealed that combined therapy increased survival rate and time up to 95% and 16 days, respectively, with an 82% reduction of tachyzoites and marked distortion, as detected by the scanning electron microscope (SEM). Additionally, combined therapy alleviated the severity and the extent of the inflammatory cells' infiltration, thereby reducing hepatocyte degeneration. Intriguingly, serum IF-γ level showed a significant increase to 155.92 ± 10.12 ng/L with combined therapy, reflecting the immunological role of the combined therapy. The current results revealed that probiotics have a high adjuvant potential in alleviating the impact of toxoplasmosis. Using probiotics as a synergistic treatment to modulate conventional therapy in systemic toxoplasmosis may gain popularity due to their low cost and current availability.

Seroprevalence of anti-Toxoplasma gondii antibodies and associated risk factors in pregnant women in Somalia

Toxoplasma gondii infection is a worldwide protozoan parasitic disease caused by the parasite Toxoplasma gondii. T. gondii infection in gestation period can lead to fetal or neonatal death, and besides congenital defects. So far, there are no data available regarding T. gondii seropositivity and associated risk factors in pregnant women in Somalia. The investigations of these aspects were done in 403 pregnant women attending the antenatal care (ANC) at Benadir hospital, in Mogadishu city. Blood samples were collected and analyzed for anti-T. gondii antibodies by enzyme-linked immunosorbent assay (ELISA). IgG seropositivity to T. gondii was 45.2% (182/403). None of the women were positive for IgM antibodies. Considering the first, second, and third trimesters of pregnancy, women IgG seropositivity was 44.2%, 26.3%, and 67.7%, respectively (p < 0.05). There was no significant association between seropositivity and age, sociodemographic features, history of abortion, presence of cats in house, contact cats feces, contact with soil, consumption of raw vegetables/meats, blood transfusion, and drinking of unboiled milk (p>0.05). Routine serological screening for T. gondii should be integrated with other ANC services to identify potential infections with the parasite.

Retrospective study of toxoplasmosis prevalence in pregnant women in Benin and its relation with malaria

Background

Globally distributed with variable prevalence depending on geography, toxoplasmosis is a zoonosis caused by an obligate intracellular protozoan parasite, Toxoplasma gondii. This disease is usually benign but poses a risk for immunocompromised people and for newborns of mothers with a primary infection during pregnancy because of the risk of congenital toxoplasmosis (CT). CT can cause severe damage to fetuses-newborns. To our knowledge, no study has been conducted in sub-Saharan Africa on toxoplasmosis seroprevalence, seroconversion and CT in a large longitudinal cohort and furthermore, no observation has been made of potential relationships with malaria.

Methods

We performed a retrospective toxoplasmosis serological study using available samples from a large cohort of 1,037 pregnant women who were enrolled in a malaria follow-up during the 2008–2010 period in a rural area in Benin. We also used some existing data to investigate potential relationships between the maternal toxoplasmosis serological status and recorded malaria infections.

Results

Toxoplasmosis seroprevalence, seroconversion and CT rates were 52.6%, 3.4% and 0.2%, respectively, reflecting the population situation of toxoplasmosis, without targeted medical intervention. The education level influences the toxoplasmosis serological status of women, with women with little or no formal education have greater immunity than others. Surprisingly, toxoplasmosis seropositive pregnant women tended to present lower malaria infection during pregnancy (number) or at delivery (presence) and to have lower IgG levels to Plasmodium falciparum Apical Membrane Antigen 1, compared to toxoplasmosis seronegative women.

Conclusions

The high toxoplasmosis seroprevalence indicates that prevention against this parasite remains important to deploy and must be accessible and understandable to and for all individuals (educated and non-educated). A potential protective role against malaria conferred by a preexisting toxoplasmosis infection needs to be explored more precisely to examine the environmental, parasitic and/or immune aspects.

Toxoplasmosis infection among pregnant women in Africa: A systematic review and meta-analysis

The epidemiology of toxoplasmosis in pregnancy is a major issue in public health. Toxoplasmosis is caused by the protozoan parasite. Toxoplasma parasite is at high risk for life-threatening diseases during pregnancy. Congenital toxoplasmosis results from a maternal infection acquired during gestation. Therefore, this systematic review and meta-analysis was aimed to determine the seropositive prevalence of toxoplasmosis infection among pregnant women who attended antenatal care in a health facility in Africa. A systematic review and meta-analysis of published and unpublished studies were included. Databases such as MEDLINE, PubMed, EMBASE, CINAHL, Web of Science, African Journals Online were used with relevant search terms. The quality of the articles was critically evaluated using the tool of the Joanna Briggs Institute. Data were extracted on Microsoft word 2016. Meta-analysis was conducted using STATA 14 software. The heterogeneity and publication bias were assessed using the I² statistics and Egger’s test, respectively. Forest plots were used to present the pooled prevalence and odds ratio with a 95% confidence interval of meta-analysis using the random effect model. In total, 23 studies comprising 7,579 pregnant women across ten countries in Africa were included in this meta-analysis. The overall prevalence of seropositive toxoplasmosis among pregnant women in Africa was 51.01% (95% CI; 37.66, 64.34). The heterogeneity test showed that heterogeneity was high, I² = 99.6%, P-value < 0.001. The variables responsible for the source of heterogeneity were included from Cameroon, the Democratic Republic of Congo, and Ethiopia. Overall prevalence of toxoplasmosis in Africa showed that more than one-half of pregnant women were infected. The risk of acquiring toxoplasmosis infection during pregnancy is high; hence, preventive measures to avoid exposure of pregnant women to Toxoplasma infection should be strictly applied.

Seroepidemiology of Toxoplasma gondii Among Pregnant Women Attending Antenatal Care in Northwest Ethiopia

Introduction

Toxoplasmosis is a life-threatening disease in pregnant women, having social and economic impacts due to congenital toxoplasmosis. However, in Ethiopia, it is neglected zoonotic disease, which requires screening and identifying risk factors in pregnant women to plan a public health intervention.

Methods

This institutional-based cross-sectional study was employed from March to April 2019 to estimate the seropositivity and assess potential risk factors for T. gondii among pregnant women attending antenatal care in four public hospitals in Northwest Ethiopia. Four hundred and one pregnant women were recruited to collect serum samples. Toxoplasma gondii antibodies were tested using Toxo-Latex slide agglutination test.

Results

Thus, the overall seropositivity for T. gondii was found 70.8% (95% CI: 66.3–75.5). Multivariable logistic regression analysis showed that the average monthly income, occupational status, habits of handwashing practices after handling raw meat, water sources for drinking and agroclimatic situations revealed significant (p < 0.05) effects on seropositivity for T. gondii in pregnant women.

Conclusion

This survey showed high seropositivity for T. gondii among pregnant women in Northwest Ethiopia. Therefore, further studies on bioassay, isolation and genotype of the pathogen are crucial. It also requires action to prevent and control the infection with T. gondii in pregnant women, which poses a potential threat to a foetus.

Toxoplasma gondii seroprevalence among pregnant women in Rabat, Morocco

BACKGROUND

Toxoplasmosis is an infectious disease caused by a protozoan parasite named Toxoplasma gondii (T.gondii). Pregnant women are considered one of the risk groups. The objective of this retrospective study is to provide an updated estimate of the seroprevalence of anti-T. gondii antibodies among a group of Moroccan pregnant women monitored at the Parasitology Laboratory of the National Institute of Hygiene in Rabat in Morocco.

METHODS

Serum samples were tested for the presence of specific anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies using indirect enzyme-linked immunosorbent assay (ELISA). Anti-Toxoplasma IgM- and IgG-positive cases were also evaluated with the anti-Toxoplasma IgG avidity test. All cases were evaluated according to the age, parity, and historical of abortion.

RESULTS

Among 677 pregnant women, 94.1% (637/677) were serologically screened for the first time and therefore had no knowledge of their serological status, and only 5.9% (40/677) were screened for the second or third time. The overall anti-T. gondii IgG and IgM seropositivity among the 637 pregnant women included in the study analysis was 43% (274/637) and 3.9% (25/637), respectively. The use of the IgG avidity test allowed excluding recent infection among 83% of cases with IgG and IgM positive sera. The mean age was 29.4 ± 6.3 years. The result of the bivariate analysis revealed that the age influenced significantly the seroprevalence rate, while the parity and the existence of previous spontaneous abortion did not have any significant statistical correlation with seropositivity to T. gondii.

CONCLUSION

This study shows that 43% of pregnant women were positive and 57% of them had no antibody against the T. gondii infection. However, the pregnancy follow-up and the counseling of pregnant women remain essential for the prevention of congenital toxoplasmosis.

Potential risk factors associated with seropositivity for Toxoplasma gondii among pregnant women and HIV infected individuals in Ethiopia: A systematic review and meta-analysis

BACKGROUND

Toxoplasma gondii is an obligate intracellular and neurotropic apicomplexan protozoan parasite infecting almost all warm-blooded vertebrates including humans. To date in Ethiopia, no systematic study has been investigated on the overall effects of potential risk factors associated with seropositivity for Toxoplasma gondii among pregnant women and HIV infected individuals. We intended to determine the potential risk factors (PRFs) associated with seropositivity for Toxoplasma gondii from published data among pregnant women and HIV infected individuals of Ethiopia.

METHODOLOGY

An systematic review of the previous reports was made. We searched PubMed, Science Direct, African Journals Online, and Google Scholar for studies with no restriction on the year of publication. All references were screened independently in duplicate and were included if they presented data on at least two risk factors. Meta-analysis using the random or fixed-effects model was made to calculate the overall effects for each exposure.

RESULTS

Of the 216 records identified, twenty-four reports met our eligibility criteria, with a total of 6003 individuals (4356 pregnant women and 1647 HIV infected individuals). The pooled prevalences of anti-Toxoplasma gondii antibodies were found at 72.5% (95% CI: 58.7% - 83.1%) in pregnant women and 85.7% (95% CI: 76.3% - 91.8%) in HIV infected individuals. A significant overall effect of anti-Toxoplasma gondii seropositivity among pregnant women (p < 0.05) was witnessed with age, abortion history, contact with cats, cat ownership, having knowledge about toxoplasmosis, being a housewife and having unsafe water source. Age, cat ownership, and raw meat consumption were also shown a significant effect (p < 0.05) to anti-Toxoplasma gondii seropositivity among HIV infected individuals.

CONCLUSIONS

This review showed gaps and drawbacks in the earlier studies that are useful to keep in mind to design accurate investigations in the future. The pooled prevalence of anti-Toxoplasma gondii antibodies was found to be higher among pregnant women and HIV infected individuals. This suggests that thousands of immunocompromised individuals (pregnant women and HIV infected patients) are at risk of toxoplasmosis due to the sociocultural and living standards of the communities of Ethiopia. Appropriate preventive measures are needed to reduce the exposure to Toxoplasma gondii infection. Further studies to investigate important risk factors are recommended to support the development of more cost-effective preventive strategies.

Human toxoplasmosis in Mozambique: gaps in knowledge and research opportunities

Toxoplasmosis is a parasitic zoonotic disease caused by Toxoplasma gondii that afflicts humans worldwide and wild and domestic warm-blooded animals. In immunocompetent individuals, the acute phase of infection presents transient low or mild symptoms that remain unnoticed. In immunocompromised patients, T. gondii is a life-threatening opportunistic infection, which can result from the reactivation of latent infection or primary infection. Moreover, congenital toxoplasmosis, which results from the transplacental passage of tachyzoites into the fetus during a pregnant primary infection, can lead to miscarriage, stillbirth, or ocular and neurologic disease, and neurocognitive deficits in the newborns. Thus, the present review aims to address the current knowledge of T. gondii infection and toxoplasmosis in Africa and especially in Mozambique, stressing the importance of identifying risk factors and promote awareness among the health care providers and population, assessing the gaps in knowledge and define research priorities. In Mozambique, and in general in southern African countries, clinical disease and epidemiological data have not yet been entirely addressed in addition to the implications of T. gondii infection in immunocompetent individuals, in pregnant women, and its relation with neuropsychiatric disorders. The main gaps in knowledge in Mozambique include lack of awareness of the disease, lack of diagnostic methods in health facilities, lack of genetic data, and lack of control strategies.

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.

Detection of human intestinal protozoan parasites in vegetables and fruits: a review

Diarrheal diseases caused by intestinal protozoan parasites are a major food-borne public health problem across the world. Vegetables and fruits provide important nutrients and minerals, but are also common sources of some food-borne human pathogenic microorganisms. The contamination of raw vegetables and fruits with human pathogenic parasites are now a global public health threat, despite the health benefits of these foods in non-pharmacological prophylaxes against diseases. A large number of reports have documented the contamination of vegetables or fruits with human pathogenic microorganisms. In this paper, we reviewed the contamination and detection methods of human pathogenic intestinal protozoans that are frequently recovered from raw vegetables and fruits. The protozoan parasites include Cryptosporidium spp., Giardia duodenalis, Cyclospora cayetanensis, Entamoeba spp., Toxoplasma gondii, Balantioides coli, Blastocystis sp., Cystoisospora belli and Enterocytozoon bieneusi. The risk factors involved in the contamination of vegetables and fruits with parasites are also assessed.

A Review on the Present Advances on Studies of Toxoplasmosis in Eastern Africa

Toxoplasmosis is a zoonotic infection caused by the protozoan parasite, Toxoplasma gondii. It was discovered over 100 years ago and is credited as the most successful parasitic organism worldwide, able to infect and multiply in all warm blooded animals including an estimated 2.3 billion people. Toxoplasmosis is asymptomatic in immunocompetent individuals. Infection in the developing fetus and immunocompromised individuals can cause severe clinical disease. Toxoplasmosis is also a major cause of reproductive failure in livestock. The economic impact of toxoplasmosis is believed to be substantial. Factors associated with toxoplasmosis infection have been defined. Eastern Africa region is a high-risk area mainly due to the close association of humans and livestock as well as sociocultural practices, poor environmental hygiene, and poverty. The present paper provides a narrative review of published data on toxoplasmosis in Eastern Africa.

A Novel wx2 Gene of Toxoplasma gondii Inhibits the Parasitic Invasion and Proliferation in vitro and Attenuates Virulence in vivo via Immune Response Modulation

Toxoplasma gondii (T. gondii) is an obligate intracellular apicomplexan protozoan that can parasitize most warm-blooded animals and cause severe diseases in immunocompromised individuals or fetal abnormalities in pregnant woman. The treatment of toxoplamosis has been limited by effective drugs. Our previous work indicated that the novel gene wx2 of T. gondii may serve as a vaccine antigen candidate. To further investigate the molecular functions of wx2 in highly virulent T. gondii (RH strain), a wx2 gene deletion mutant RH strain (KO-wx2) was established using CRISPR-Cas9. The phynotype of KO-wx2 was analyzed by plaque, invasion, and replication assays in vitro as well as in vivo virulence assays. The results indicated that the targeted deletion of the wx2 gene significantly inhibited in vitro parasite growth and replication in the host cells as well as attenuated parasite virulence in the mouse model. Notably, the percentage of pro-inflammatory factors of interferon gamma (IFN-γ) and interlukin-17A (IL-17A) and anti-inflammatory factor of interlukin-10 (IL-10) in the lymph nodes were upregulated in mice infected with the KO-wx2 strain. Our data suggested that the wx2 gene plays an important role in the process of the parasite’s life cycle and virulence in mice. In addition, it also plays an important role in the host’s immunity reaction, mainly via Th1 and Th17 cellular immunity, not Th2.

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 and molecular screening of umbilical cord blood for Toxoplasma gondii infection

BACKGROUND

Human umbilical cord blood has proven to be a successful alternate source of hematopoietic stem cells for pediatric patients with major hematologic disorders. Toxoplasma gondii is a global opportunistic protozoan which cause fatal complications in immunocompromised individuals.

AIM

Our goal is to study the prevalence of toxoplasmosis in umbilical cord blood (UCB) and to assess the sensitivity of ELISA and PCR for Toxoplasma infection screening.

MATERIAL AND METHODS

One hundred cord blood samples were collected immediately after delivery. Anti-Toxoplasma IgG and IgM antibodies were determined using ELISA method; Toxoplasma DNA was detected using nested PCR technique. Total nucleated cells (TNC) and HB were also determined. Demographic data and risk factors data related to the transmission of toxoplasmosis, were collected from mothers.

RESULTS

Among 100 cord blood samples, 36 (36%) were positive for anti-Toxoplasma IgG antibodies and 6 (6%) were positive for anti-Toxoplasma IgM antibodies. The nested PCR showed 11 (11%) samples containing Toxoplasma DNA from which, 6 (55%) samples were IgM positive. There was no significant association between the risk of Toxoplasma transmission and cord blood positivity for toxoplasmosis.

CONCLUSION

Owing to the prevalence of toxoplasmosis, its rapid progression and its fatal outcome in immunocompromised patients, cord blood screening for toxoplasmosis with nested PCR should be incorporated into cord blood bank screening protocols.