Rubella infections

As part of the FMFi- Look for life education outreach, we are starting a monthly newsletter covering subjects which will help towards addressing the problems of perinatal mortality and still birth. The first of these is fetal infections of which the most preventable cause of severe neonatal morbidity is congental rubella infections.

Universal rubella immunization is part of the Govt of India’s childred immunisation programme but nevertheless any woman who is planning pregnancy or is seen at any time during pregnancy has to have her IGG Rubella status checked. ( please note that it is important to not just do an IGM whenever infection screening is done and both IGG and IGM values need to be checked so that correct advice can be given.

Rubella, also called German measles, is a disease of childhood . In the absence of pregnancy, it is usually clinically manifested as a mild self-limited infection.During pregnancy, however, the virus can have potentially devastating effects on the developing fetus. It has been directly responsible for inestimable wastage and for severe congenital malformations.

Recommendations

  • The risk of congenital defects has been reported to be 90% when maternal infection occurs before 11 weeks of gestation, 33% at 11–12weeks, 11% at 13–14 weeks, 24% at 15–16 weeks, and 0% after 16 weeks.7.Since the effects of congenital rubella syndrome vary with the gestational age at the time of infection, accurate gestational dating should be established, as it is critical to counselling. (II-3A)
  • The diagnosis of primary maternal infection should be made by serological testing. (II-2A) The presence of a rubella
    • A fourfold rise in rubella IgG antibody titre between acute and convalescent serum specimens
    • A positive serologic test for rubella-specific IgM
    • A positive rubella culture (isolation of rubella virus in aclinical specimen from the patient)
  • Serologic studies are best performed within 7 to 10 days after the onset of the rash and should be repeated two to three weeks later.
  • Screening to determine the antibody status of all pregnant women to determine susceptibility. Providing programs to ensure postpartum immunization of non-immune women before they are discharged from the hospital.
  • Women who have been inadvertently vaccinated in early pregnancy or who become pregnant immediately following vaccination can be reassured that there have been no cases of congenital rubella syndrome documented in these situations. (III-B)
  • Women wishing to conceive should be counselled and encouraged to have their antibody status determined and undergo rubella vaccination if needed. (I-A)
  • Congenital defects and late manifestations of rubella infection:
    Present at birth Late manifestations : Audiologic anomalies (60–75%) ,Sensorineural deafnessCardiac defects (10–20%) – Pulmonary stenosis , Patent ductus arteriosus, Ventricular septal defectOphthalmic defects (10–25%) –Retinopathy , Cataracts , Microphthalmia , Pigmentary and congenital glaucoma

    Central nervous system (10–25%) – Mental retardation , Microcephaly ,Meningoencephalitis

    Others – Thrombocytopenia , Hepatosplenomegaly ,Radiolucent bone disease ,Characteristic purpura (Blueberry muffin appearance) , Diabetes mellitus , Thyroiditis ,Growth hormone deficit , Behavioural disorder

    (SOGC Guidelines 2008)