Sero-prevalence of rubella among pregnant women in India, 2017.

BACKGROUND: We conducted a sero-survey among pregnant women attending antenatal clinics of six hospitals which also function as sentinel sites for CRS surveillance, to estimate the prevalence of IgG antibodies against rubella. METHODS: We systematically sampled 1800 pregnant women attending antenatal clinics and tested their sera for IgG antibodies against rubella. We classified sera as seropositive (titre ≥10 IU/ml), sero-negative (titre <8 IU/ml) or indeterminate (titre 8-9.9 IU/ml) per manufacturer's instructions. In a sub-sample, we estimated the titers of IgG antibodies against rubella. IgG titer of ≥10 IU/mL was considered protective. RESULTS: Of 1800 sera tested, 1502 (83.4%) were seropositive and 24 (1.3%) were indeterminate and 274 (15.2%) were sero-negative. Rubella sero-positivity did not differ by age group, educational status or place of residence. Three hundred and eighty three (87.8%) of the 436 sera had IgG concentrations ≥10 IU/mL. CONCLUSION: The results of the serosurvey indicate high levels of rubella sero-positivity in pregnant women. High sero-prevalence in the absence of routine childhood immunization indicates continued transmission of rubella virus in cities where sentinel sites are located.

Sentinel Surveillance for Congenital Rubella Syndrome - India, 2016-2017.

Rubella infection during pregnancy can result in miscarriage, fetal death, stillbirth, or a constellation of congenital malformations known as congenital rubella syndrome (CRS). The 11 countries in the World Health Organization (WHO) South-East Asia Region are committed to the elimination of measles and control of rubella and CRS by 2020. Until 2016, when the Government of India's Ministry of Health and Family Welfare and the Indian Council of Medical Research initiated surveillance for CRS in five sentinel sites, India did not conduct systematic surveillance for CRS. During the first 8 months of surveillance, 207 patients with suspected CRS were identified. Based on clinical details and serologic investigations, 72 (34.8%) cases were classified as laboratory-confirmed CRS, four (1.9%) as congenital rubella infection, 11 (5.3%) as clinically compatible cases, and 120 (58.0%) were excluded as noncases. The experience gained during the first phase of surveillance will be useful in expanding the surveillance network, and data from the surveillance network will be used to help monitor progress toward control of rubella and CRS in India.