Positive predictive value of seroconversion or positive rubella IgM in diagnosis of maternal rubella infection

Seroepidemiology study of rubella virus antibodies among neonates and pregnant women at hospitals in Henan province, China

“…30 Childbearing-age women are routinely screened for rubella antibodies to identify and vaccinate susceptible women. 25 Our findings showed that 79.3% of the pregnant women were seropositive for rubella IgG, similar to those reported in other Chinese cities (81.97%), such as Shenyang, Kunming, Chengdu, and Yantai. 31 Since none of the pregnant women had been vaccinated against the rubella vaccine, the high IgG antibody seropositivity indicated the continued transmission of rubella in the Henan province of China.…”

“…Infection with the rubella virus in early pregnancy can lead to miscarriages, fetal death, or the birth of neonates with CRS 30 . Childbearing‐age women are routinely screened for rubella antibodies to identify and vaccinate susceptible women 25 . Our findings showed that 79.3% of the pregnant women were seropositive for rubella IgG, similar to those reported in other Chinese cities (81.97%), such as Shenyang, Kunming, Chengdu, and Yantai 31 .…”

“…In this study, The seroprevalence of anti‐rubella IgG antibodies was 68.7% in neonates and 79.3% in pregnant women. Since none of the neonates and pregnant women in this study had been vaccinated against any rubella‐containing vaccine, the neonates probably obtained the IgG antibodies from their mothers during pregnancy, and the pregnant women presumably acquired the IgG antibodies by wild‐type rubella virus infection 25,26 . We also found that 28 participants were seropositive for anti‐rubella IgM antibodies, indicating that rubella virus infection was ongoing in this region.…”

Evaluation of Diagnostic Accuracy of Eight Commercial Assays for the Detection of Rubella Virus-Specific IgM Antibodies

“…Furthermore, in the event of rubella IgM testing when not clinically indicated, such as in screening of pregnant women, the test results arguably provide more harm than good. One recent study from the national reference laboratory in France, estimated the positive predictive value of rubella IgM serology used to assess maternal primary rubella infection at only 1.4% (23). In these settings, alternative laboratory diagnostic methods with higher specificity and sensitivity, such as viral detection by RT-PCR, which has the added benefit of facilitating viral genotypic surveillance, are preferable for case confirmation.…”

“…In summary, none of the methods for detecting anti-rubella IgM antibody evaluated in this study had the combination of high sensitivity and high specificity that is needed to support monitoring of elimination goals, although this could be somewhat compensated for by taking a presumptively positive approach to specimens with equivocal results (particularly Microimmune and Euroimmun glycoprotein methods). These underperforming methods, when combined with low rubella prevalence in elimination settings, lead to poor predictive ability and are therefore of limited value ( 5 , 6 , 21 – 23 ). A study conducted in the province of Ontario, Canada, a setting without endemic circulation of rubella, reported that the positive predictive value of a positive rubella IgM test for case confirmation was 3.6% ( 22 ).…”