Summary
Introduction: Rubella infection in pregnancy may cause severe complications, including still birth, miscarriage, preterm labor, growth deficiency, congenital malformation, blindness, cardiac defects, central nervous system abnormalities, and congenital cataract and hearing loss. The purpose of this study was to investigate the seroprevalence of rubella in pregnant women presenting to our hospital for routine antenatal examination, to compare our results with those from other countries, and to contribute to the literature by discussing opinions concerning rubella screening in pregnancy with data from 27.465 patients.
Material and Methods: This retrospective study involved anti-rubella IgM and IgG screening results of pregnants in the first trimester, aged 17-45 and presented to our hospital for antenatal examination between 2013 and 2016. Data were collected from the hospital"s electronic records system and patient files. Rubella antibody levels were determined using commercially available ELISA kits (ALISEI SEAC, Italy) in the medical microbiology laboratory. Anti-rubella IgM-positive cases were also evaluated using the avidity test. The results were analyzed using the SPSS v.15.0 (SPSS Inc., Chicago, Illinois, USA) data analysis system.
Results: Rubella IgM antibody positivity was determined in 205 (0.8%) of 27.465 pregnants whose anti-rubella IgM status was investigated, and positive values were observed in 16.526 (9.2%) of 17.186 cases subjected to anti-rubella IgG antibody analysis. Anti-rubella avidity tests revealed high avidity in 92.7% of patients, low avidity in 3.4%, and intermediate avidity in 3.9%.
Conclusion: We think that rubella screening during pregnancy is essential, and that the best means of reducing the adverse effects of rubella virus would be to provide full immunization before pregnancy for females of child-bearing age.
Introduction
Rubella infection during pregnancy may cause teratogenicity and represents a major community health problem. In early pregnancy, and especially in the first trimester, almost the entire fetus becomes infected as a result of maternal infection eight weeks after menstruation. Congenital malformation develops in most of the infected fetuses. There is a 90% risk of congenital malformation as a result of primary rubella infection in the first trimester. The disease, known as congenital rubella syndrome, may also cause congenital cataract, deafness, mental retardation, and cardiac defects[2].
Rubella seropositivity rates in different countries range between 54.1% and 95.2%[3].
Rubella-IgG seropositivity indicates past infection or immunization. However, rubella-IgM seropositivity is usually a sign of active infection or recent vaccination. Negative results indicate that no antibody is detected. Acute infection and nonspecific bonding reaction may give rise to uncertain results. As a result of studies on the subject of (Toxoplasmosis, Rubella, Cytomegalovirus, Herpes simplex virus) TORCH, pregnant women with a poor obstetric history are now advised to receive routine TORCH check-ups, meaning that complications can be managed easily[4].
The American College of Obstetricians and Gynecologists recommends routine screening in early pregnancy for detecting rubella infections. Check-ups will make it possible to identify a history of rubella infection or immunization. Rubella is a systemic disease, and vaccination can provide protection against it. Vaccination is recommended for women of childbearing age. The purpose of this descriptive study was to determine the rubella seroprevalence in our secondary-care hospital in Turkey and to compare our findings with other national data.
Methods
Blood samples were collected from the 1st trimester pregnants presenting to the Erzurum Nene Hatun Maternity Hospital for antenatal check-ups between January, 2013 and January 2017. The samples were analyzed in the microbiology laboratory using the Micro-ELISA method (ALISEI SEAC, Italy). Anti-rubella IgM and anti-rubella IgG values were obtained retrospectively from the hospital electronic records system and patient files. Avidity of anti-rubella IgG in anti-rubella IgM-positive cases were also evaluated. Patients with multiple serology results were excluded from the study. The results were analyzed using SPSS v.15.0 (SPSS Inc., Chicago, Illinois, USA).
Discussion
The rubella prevalence varies among different countries: 53% in Nigeria[6], 76% in Sri Lanka[7], 77.5% in Russia[8], 94.1% in Spain[9], 93.4% in Haiti[10], 93% in Australia[11], 89.1% in Taiwan[12], 87% in Germany[13], 72% in Sudan[14], and 96% in Iran[15]. Studies investigating the prevalence of rubella in Turkey are listed in Table 4.
Rubella vaccine is an attenuated vaccine used as a trivalent vaccination against measles, mumps and rubella (MMR) or as a monovalent vaccine for rubella alone. It is not recommended during pregnancy. Rubella vaccination has been included in the national immunization program in Turkey since 2006. MMR vaccine is administered to children in two doses; the first dose is for children in their 12th month, while the second is for children aged seven. The rubella IgG level in this study was 99.4%, indicating probably the success of this vaccination program.
Screening pregnant women for rubella is a controversial subject. In the United States of America (USA), rubella serology screening is recommended at the first prenatal visit, while in the United Kingdom, routine monitoring for rubella is not recommended. The USA introduced and has achieved the goal of eliminating endemic rubella transmission and congenital rubella syndrome. Elimination of endemic rubella was documented and verified in the USA in 2004. However, there is still a strong likelihood of imported cases of rubella because of international travel and countries lacking routine rubella vaccination. In order to maintain elimination, the USA should continue to achieve high vaccination rates among children, to ensure that women of childbearing age, particularly women born outside the country, are vaccinated, and to maintain sensitive surveillance in order to detect both rubella and congenital rubella syndrome. Particular care should be taken when rubella IgM is detected in a pregnant woman with no history of illness or contact with a rubella-like illness. Although this is not recommended, many pregnant women with no known exposure to rubella are nevertheless tested for rubella IgM as part of their prenatal care regimen. Additional laboratory evaluation should be performed if rubella test results are IgM-positive for individuals with no or low risk of exposure to rubella[23, 25].
A recent short report from the United Kingdom discussed a failure to protect women against rubella infection by the MMR vaccination program. The number of pregnant women susceptible to rubella in the West Midlands in England rose from 1.4% to 6.9 in 2011. The investigators concluded that screening for rubella in pregnancy offers no advantages in terms of the current pregnancy and that it may be time to review the universal MMR vaccination program, which would in turn would eliminate the need for maintaining this practice[26].
The aim of screening is to prevent rubella virus infecting others by identifying rubella unimmunized individuals and to prevent congenital rubella syndrome, with the help of postnatal vaccination. A further aim is to detect active infection with the help of check-ups and to provide necessary management of rubella infection.
The presented study has several limitations. First, only the results of patients in the hospital electronic records system were analyzed. Second, clinical conditions, such as vaccine history and rash, in IgM seropositive patients could not be evaluated. In addition, information concerning curettage, amniotic biopsy or malformation in patients with IgM seropositivity and moderate and low avidity was not available.
Conclusion
Although we believe that investigation of rubella during pregnancy is essential, the best approach in terms of reducing the adverse effects of rubella virus would be to provide full immunization before pregnancy for young women of child-bearing age.
Ethics
Ethics Committee Approval: Since this was a retrospective study, there was no need for ethical committee approval.
Informed Consent: Since this was a retrospective chart review study, there was no informed consent.
Peer-review: Externally and internally peer-reviewed. Authorship Contributions
Surgical and Medical Practices: E.Ç.T., L.D., Concept: E.Ç.T., Z.Ö., Design: B.G.K., H.A., Data Collection or Processing: E.Ç.T., B.G.K., H.A., Analysis or Interpretation: E.Ç.T., Z.Ö., Literature Search: E.Ç.T., L.D., Writing: E.Ç.T., L.D., H.A.
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: The authors declared that this study received no financial support.
