Seroprevalence of Toxoplasmosis at a Tertiary Care Centre in North India from 2004 to 2014

Seroepidemological investigation of Toxoplasma gondii and Trichinella spp. in pigs reared by tribal communities and small-holder livestock farmers in Northeastern India

Toxoplasma gondii and Trichinella spp. are critical tissue-dwelling foodborne zoonotic parasites associated with pork consumption and pig rearing. Despite being a major pig-rearing region in the country, Northeastern India has not undergone any investigation regarding the presence of T. gondii and Trichinella spp. in pigs. Therefore, this study aims to determine the seroprevalence of T. gondii and Trichinella spp. and identify associated risk factors in pigs reared by tribal communities and small-holder livestock farmers in the northeastern region of India. In a cross-sectional serological survey, 400 pigs from 400 households across five northeastern states of India underwent testing for the seroprevalence of porcine toxoplasmosis and trichinellosis. Serum samples (80 from each state) were analyzed using commercially available ELISA assays. Data on backyard farm characteristics and various management aspects were collected, and risk factors linked with prevalence were analyzed through univariate and multivariate logistic regression analysis. The findings revealed that the apparent and true prevalence of anti-T. gondii antibodies were 45% (40.12-49.88, 95% CI) and 45.7% (40.7-50.69, 95% CI), respectively. As for anti- Trichinella antibodies, both the apparent and true prevalence were 0.75% (-0.1-1.6, 95% CI). The univariate and multivariate analyses indicated that age above 24 months (OR 7.20, 95% CI 2.45-23.71), exposure to cats (OR = 5.87, 95% CI 2.55-14.05), and farms operating for breeding purposes (OR = 5.60, 95% CI 3.01-11.04) were significant risk factors associated with the seroprevalence of T. gondii. This study marks the initial documentation of the seroprevalence of T. gondii and Trichinella spp. in pigs reared by tribal communities in Northeastern India. The results emphasize the significance of these parasites as foodborne zoonotic threats in the region, potentially posing substantial public health risks, especially within tribal and rural communities. The insights derived from this research could be valuable in formulating targeted preventive and control strategies against T. gondii and Trichinella spp. in pigs, not only in this region but also in areas with similar rearing practices.

Toxoplasmosis lymphadenopathy-A series of 8 cases diagnosed in a 2-year timeframe: Is it a needle in a haystack?

Toxoplasmosis is a zoonosis caused by Toxoplasma gondii, an obligate intracellular parasite. Clinical presentation of infection depends on the age and immune status of the patient. In immunocompetent patient, it may present as a non-specific lymphadenopathy and self- limiting illness. In contrast, in immunocompromised patients it can be a life-threatening infection. We present a series of 8 cases of toxoplasma lymphadenitis diagnosed in our institute in last two years. Lymphadenopathy raises a suspicion of malignancy; however, diagnosis of reactive lymphadenitis often marks the end of diagnostic evaluation. Careful morphological evaluation, the classic triad, often can direct at a conclusive diagnosis. We are presenting a case series to draw attention to this entity as majority of the published literature is in the form of case report and serological surveys and very occasional study showing both the histopathology and serology in tandem.

Pregnancy, infection, and epigenetic regulation: A complex scenario

A unique immunological condition, pregnancy ensures fetus from maternal rejection, allows adequate fetal development, and protects against microorganisms. Infections during pregnancy may lead to devastating consequences for pregnant women and fetuses, resulting in the mother's death, miscarriage, premature childbirth, or neonate with congenital infection and severe diseases and defects. Epigenetic (heritable changes in gene expression) mechanisms like DNA methylation, chromatin modification, and gene expression modulation during gestation are linked with the number of defects in the fetus and adolescents. The feto-maternal crosstalk for fetal survival during the entire gestational stages are tightly regulated by various cellular pathways, including epigenetic mechanisms that respond to both internal as well outer environmental factors, which can influence the fetal development across the gestational stages. Due to the intense physiological, endocrinological, and immunological changes, pregnant women are more susceptible to bacterial, viral, parasitic, and fungal infections than the general population. Microbial infections with viruses (LCMV, SARS-CoV, MERS-CoV, and SARS-CoV-2) and bacteria (Clostridium perfringens, Coxiella burnetii, Listeria monocytogenes, Salmonella enteritidis) further increase the risk to maternal and fetal life and developmental outcome. If the infections remain untreated, the possibility of maternal and fetal death exists. This article focused on the severity and susceptibility to infections caused by Salmonella, Listeria, LCMV, and SARS-CoV-2 during pregnancy and their impact on maternal health and the fetus. How epigenetic regulation during pregnancy plays a vital role in deciding the fetus's developmental outcome under various conditions, including infection and other stress. A better understanding of the host-pathogen interaction, the characterization of the maternal immune system, and the epigenetic regulations during pregnancy may help protect the mother and fetus from infection-mediated outcomes.

Molecular evidence of toxoplasmosis in people living with HIV in Pakistan

BACKGROUND

Toxoplasma gondii is a zoonotically important parasite infecting almost all vertebrates. The parasite can easily infect humans through the fecal-oral route, particularly immunocompromised individuals, and children. Due to lack of epidemiological data regarding the occurrence of Toxoplasma gondii in people living with HIV in Pakistan, the present study was designed to estimate the prevalence of Toxoplasma gondii in people living with HIV.

METHODS

Briefly, 384 blood samples were randomly collected from people living with HIV registered under Punjab AIDS Control Program. DNA of all samples was extracted and the 18S rRNA gene of T. gondii was amplified through polymerase chain reaction (PCR) by using genus-specific primers. The amplicons were spread on 1.5% agar rose gel and visualized under gel documentation system. Then the amplicons were purified from the gel and subjected to sequence and phylogenetic analysis.

RESULTS

Overall prevalence of T. gondii was observed as 23.96%. The prevalence of T. gondii was significantly (p <0.05) higher in females and in middle age group (26-40 years). Similarly, the prevalence was significantly (p <0.05) higher in people with poor socioeconomic status, symptomatic patients, drugs users and people using unfiltered water for drinking. Furthermore, bodyweight (46-70 kg) and dry seasons also significantly (p <0.05) affected the prevalence of T. gondii.

CONCLUSIONS

Our findings illustrated a high infection rate of toxoplasmosis in people living with HIV which could be a significant cause of mortality. More studies need to be conducted for other opportunistic infections caused by parasites and other pathogens.

Seroprevalence and Determinants of ToRCH Pathogens in Pregnant Women in the Sub-Himalayan Region

Introduction

Toxoplasma gondii (TG), rubella virus (RV), cytomegalovirus (CMV), and herpes simplex virus type 1 and 2 (HSV 1 and 2) cause mild maternal morbidity but have serious fetal consequences. The prevalence of these infections varies widely by country and population subgroup, and the paucity of data from the hilly state of Uttarakhand prompted us to undertake this study on their seroprevalence and association with potential risk factors.

Methods

Serum samples received from pregnant women attending the antenatal clinic of All India Institute of Medical Sciences, Rishikesh, between January 2016 to December 2019 were tested for TG-, RV-, CMV, and HSV-specific IgM and IgG by capture enzyme-linked immunoassay (ELISA). The data were then analyzed to determine the seroprevalence of the major ToRCH infections (toxoplasmosis, other (syphilis, varicella-zoster, parvovirus B19), rubella, cytomegalovirus, and herpes), and Fisher’s exact test was applied to check association with potential risk factors.

Results

Out of 165 pregnant women who were screened for the four major ToRCH pathogens, overall seroprevalence was 41.2% for TG (IgM=13.3%; IgG=38.2%), 80.0% for RV (IgM=3.0%; IgG=80.0%), 61.8% for CMV (IgM=1.8%; IgG=61.8%), and 42.4% for HSV (IgM=4.3%; IgG=40.6). TG was significantly associated with increasing maternal age (p-value=0.007). The seropositivity of RV was maximum in the drier and windy months of January-March (p-value=0.004), while that of TG in the warmer months of April-June (p-value=0.03). HSV prevalence was comparatively more common in Muslim women (p-value=0.05). Women presenting with bad obstetric history (BOH) and multiparous women were at higher risk for TG-RV-HSV and TG-RV-CMV, respectively.

Conclusion

Considering the high prevalence and risk of ToRCH infections in this region, we suggest disease-specific screening based on maternal history. Recognition of the burden of ToRCH infections in pregnant women is vital in clinicians’ decisions and implementing control measures.

A contemporary insight into the sero-epidemiology of Toxoplasma gondii infection in the foot-hills of Himalayas: A cross-sectional study from a tertiary care center in Northern India

Background

Toxoplasma gondii infects 30-50% of the world's population with high diversity in the geo-epidemiology and seroprevalence. The burden of toxoplasmosis and its determinants from remote and vulnerable regions of India is unknown. Therefore, this study aim to evaluate the prevalence of toxoplasma antibodies and factors associated with seropositivity among individuals from Uttarakhand and adjoining areas.

Methods

Serum samples from 442 cases were tested for anti-Toxoplasma IgG and IgM antibodies by Enzyme-linked Immunosorbent Assay. Association of seropositivity of toxoplasmosis with age, gender, place of residence, dietary habits, and comorbidities were analyzed using binary logistic regression analysis.

Results

The overall Toxoplasma seropositivity was found to be 36.88% [95% Confidence Interval (CI)=30.40-39.28]. While anti-T. gondii IgG was present in 34.84% [95% CI=30.40-39.28], anti-IgM was detected in 6.33% [95% CI=4.06-8.61]. The overall and IgG seroprevalence increased with age in both the genders and there was a sharp increase in the seropositivity after the age of 40 years [adjusted Odds Ratio (aOR)=2.98, p-value=0.030]. The seropositivity rate was significantly higher in individuals from Uttarakhand in both the hilly region (aOR=5.61; 95%CI:[2.14-14.68]) and plains (aOR=5.14; 95%CI:[2.2-12.02]). Multivariable logistic regression analysis also showed that being rural residents (aOR=3.23; 95%CI:[1.67-6.23]) and presence of comorbidities (aOR=8.64; 95%CI:[4.62-16.18]) were potential risk factors of Toxoplasmosis. On the other hand, consumption of vegetarian diet was found to have a protective effect (aOR=0.46; 95%CI:[0.28-0.75]).

Conclusion

Seroprevalence of T. gondii antibodies was relatively high in Uttarakhand, particularly in rural and hilly terrain, indicating a necessity for the implementation of integrated public health strategies to prevent and control toxoplasmosis in this region.