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

Serological Screening of TORCH Pathogen Infections in Infertile Women of Childbearing Age in Northwest China

Serological screening for TORCH(Toxoplasma gondii [TOX], Rubella virus [RV], Cytomegalovirus [CMV], and Herpes simplex virus [HSV]) infections is an effective method for preventing congenital infections caused by TORCH pathogens.In this study, we retrospectively analyzed the characteristics of TORCH infections in 17,807 infertile women of childbearing age in northwest China.We conducted serological detection of TORCH-pathogen-specific IgM and IgG antibodies. The seroprevalence of TORCH infections was statistically analyzed by applying χ2 and Fisher exact-probability tests to evaluate the differences among ages and across quarters of the year. The overall IgM/IgG seroprevalences of TOX, RV, CMV, HSV-1, and HSV-2 were 0.46/3.4%, 0.77/84.93%, 0.68/97.54%, 1.2/82.83%, and 0.62/10.04%, respectively. The positive rates for RV-IgM in women ≥ 40 years old were significantly higher than those for women 25-39 (P < 0.05) years of age. The seroprevalence of HSV1-IgM was higher in the third and fourth quarters of the year (seasons) (P < 0.001), and the seroprevalence of CMV-IgG was statistically significant between differences quarters (P = 0.017), and the seroprevalence of CMV-IgG in the first quarter was lower than that in the third and fourth quarters (Bonferroni correction, P = 0.009 > 0.0083), suggesting no statistically significant difference between the latter two groups. This study showed that in northwestern China the risk of acquiring primary infection by a TORCH pathogen among infertile women of childbearing age were still high, especially Toxoplasma gondii and Herpesvirus type 2 infection. Therefore, effective prevention strategies that include serological screening for TORCH should be implemented.

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.