Among the viruses that can cause congenital deformities in fetuses, rubella virus is the most common and has the highest teratogenicity rate. When pregnant women are infected with the rubella virus, the virus can infect the fetus through the placenta. During the formation of the fetus’s organs, the rubella virus can lead to various types of congenital birth defects, and even result in miscarriage or stillbirth. Commonly affected areas include the eyes, ears, cardiovascular system, and nervous system. If the fetus survives, the newborn may experience growth retardation, with lower birth weight, height, head circumference, and chest circumference compared to normal newborns. This condition often persists at the age of 1, accompanied by feeding difficulties, weakness, and irregular breathing. Symptoms such as purpura, anemia, osteitis, hepatitis, pancreatitis, pneumonia, encephalitis, and heart failure can occur within the first 6 months after birth. The anterior fontanelle is usually full, and muscle tone is reduced. Reports suggest that rubella virus infection accounts for approximately 5% of birth defects in newborns(sources from therapeutique-dermatologique.org).
Testing of the throat, blood, urine, cerebrospinal fluid, and other bodily fluids of infants with congenital rubella can isolate the virus, with the highest positivity rate within the first year. There have even been reports of rubella virus persisting in affected individuals beyond the age of 12, causing rubella encephalitis. While most affected children exhibit clinical symptoms at birth, some may not develop symptoms or new deformities until several months or even years after birth. Symptoms appearing after the age of 1 may include deafness, developmental delays, speech disorders, and skeletal abnormalities.
Rubella virus infection can lead to a wide range of fetal deformities, including ocular conditions like cataracts, glaucoma, iridocyclitis, and microphthalmia; ear conditions such as sensorineural deafness, vestibular impairment, otitis media, and mutism; cardiovascular conditions like patent ductus arteriosus, pulmonary artery stenosis, myocardial necrosis, and hypertension; neurological conditions like encephalitis, meningitis, microcephaly, and intellectual disability; and hematological conditions like thrombocytopenic purpura, erythroblastopenia, and hemolytic anemia, among others. These various deformities are collectively referred to as Congenital Rubella Syndrome.
Currently, there is no specific treatment for rubella in clinical practice. Prevention is the preferred approach, with rubella vaccination being highly recommended. The use of attenuated live vaccines for immunization can yield a seroconversion rate of over 95%, and the antibodies produced can provide lifelong protection. After vaccination, some individuals may experience short-term reactions such as fever, rash, lymphadenopathy, and joint pain(quotes from therapeutique-dermatologique.org).
Because the attenuated live vaccine can infect the fetus through the placenta and cause fetal deformities, it is not advisable to be vaccinated during the preconception period or pregnancy. If the rubella vaccine has been administered, it is recommended to avoid pregnancy within three months after vaccination and use contraception during this time. If a woman is already pregnant, vaccination with this vaccine is also not advisable. Currently, rubella vaccination is commonly administered as part of routine immunization, often combined with measles and mumps vaccines(sources from therapeutique-dermatologique.org).
In cases where recent exposure to the rubella virus is confirmed, immunoglobulin injections were previously recommended for prevention. However, the effectiveness of this method in preventing rubella remains uncertain, and its use is not currently recommended. The impact of rubella attenuated live vaccine on the human body, particularly on fetuses, is not fully understood, but theoretically, it can have adverse effects.