Disease Description (Causes and Symptoms)
- Cause: It is transmitted through respiratory droplets of the rubella virus (Rubella virus, family Togaviridae). The incubation period is usually 14–21 days.
- Pathophysiology: After multiplying in the upper respiratory tract mucosa, the virus spreads through the bloodstream and may invade the skin, lymph nodes, placenta, and other tissues throughout the body. If the fetus becomes infected through the placenta early in pregnancy, congenital anomalies (congenital rubella syndrome, CRS) may occur.
- Main symptoms: Mild prodromal symptoms such as fever and malaise; a pink rash that begins on the face and spreads to the trunk and limbs within several hours to 1–2 days (usually disappearing within 3 days); enlargement of the posterior and postauricular (posterior cervical and subauricular) lymph nodes (characteristic); mild cough, pharyngeal erythema, and conjunctival injection. Adults may experience arthralgia, myalgia, or more severe systemic symptoms.
- Contagious period: Infectivity generally begins 7 days before rash onset and continues until approximately 7 days after rash onset, so clinically, caution is needed during the period before and after the rash appears.
- Immunity: Natural infection usually results in lifelong immunity.
Treatment
- General principles: Supportive treatment (rest, hydration, antipyretics and analgesics, etc.). There is no specific antiviral medication for rubella.
- Medications: Antipyretics (such as acetaminophen) and, if necessary, analgesics. Aspirin should be used with caution in children and adolescents when prescribed (risk of Reye syndrome).
- Hospitalization/specialist treatment: Hospitalization and symptom-specific specialist treatment are required in cases of severe complications (e.g., encephalitis or severe thrombocytopenia). In congenital infection (newborns), surgical and rehabilitative treatment based on individual anomalies (cardiac anomalies, cataracts, hearing loss, etc.) and multidisciplinary care are necessary.
- Pregnancy-related measures: If a pregnant woman has been exposed or is suspected of having symptoms, she should immediately visit a medical institution and undergo serologic testing (IgM, IgG) and viral testing (PCR). Immunoglobulin (IVIG) after exposure does not reliably prevent fetal infection, so its use should be decided after consultation. If rubella is confirmed during pregnancy, consult specialists (infectious disease medicine, obstetrics and gynecology, genetic counseling, etc.) regarding the prognosis for the mother and fetus. Because rubella during pregnancy carries a high risk of fetal anomalies, detailed examinations such as prenatal ultrasonography and fetal echocardiography, along with counseling, are necessary; depending on the circumstances, counseling about whether to continue the pregnancy may be provided.
- Prevention (including therapeutic significance): The key to prevention is vaccination with the live MMR (measles, mumps, and rubella) vaccine. Live vaccines are contraindicated during pregnancy, and pregnancy should be avoided for at least 4 weeks after vaccination. Women of childbearing age who lack immunity are recommended to receive the vaccine before pregnancy.
Checklist Before an Outpatient Visit (Including Preparation Items and Example Questions)
- Items to prepare (recommended to bring)
- The exact date when symptoms recently began (including the date the rash started) and a record of symptom changes
- Contact history (whether you recently had contact with a person with rubella, and any history of overseas travel)
- Pregnancy status (including plans or possibility of pregnancy) and gestational age (if applicable)
- Past vaccination records (especially whether and when MMR vaccination was received) or a history of previous rubella infection
- A list of medications currently being taken and underlying conditions (including immunocompromised status)
- Recent test results (if available)
- Examples of basic items to ask the patient about during an outpatient visit
- When did the rash start? Did it start on your face at first?
- Is there anyone around you with the same symptoms (rash or fever)?
- Have you recently become pregnant, or is pregnancy possible?
- Have you ever received the MMR vaccine? (When, and how many doses?)
- Do you have any other symptoms, such as fever, joint pain, hearing loss, or vision problems?
Examples of General Questions to Ask the Doctor
- What are the side effects of this medication (antipyretic/analgesic)? Is it safe to take, especially during pregnancy?
- How likely are my symptoms (or my family member’s symptoms) to transmit the infection to other people, especially pregnant women? How long should isolation last?
- What tests are needed to determine my immune status (serum IgM/IgG, PCR, etc.)? When should the tests be performed, and how are the results interpreted?
- If vaccination is needed, when and under what circumstances should I receive it? When can I become pregnant after vaccination?
Examples of Disease-Specific Questions
- Pregnancy-related (if applicable): "I was exposed when I was ___ weeks pregnant. Could you explain the risk of fetal infection and any additional tests that can be used (ultrasound, fetal blood testing, etc.)?"
- Prevention and vaccination: "I have not received the MMR vaccine. Given my current age and health status, please tell me whether vaccination is recommended and about pregnancy planning after vaccination (when it will be safe to become pregnant)."
(Reference) The risk of congenital rubella syndrome is highest in early pregnancy (especially the first trimester). In the event of suspected infection or exposure, immediately visit a medical institution and report to and consult with public health authorities.