Comments
INITIAL SYMPTOMS:
Low-grade fever; posterior auricular and posterior cervical adenopathy; and maculopapular rash, clinically indistinguishable from measles, dengue, erythema infectiosum, roseola, scarlet fever and other febrile exanthems; [CCDM]
FINDINGS:
The infection is asymptomatic or without fever in up to 50% of cases. Children usually present with the rash, while adults usually have 1-5 days of mild prodromal symptoms (low-grade fever; malaise, headache, cervical adenopathy; rhinitis, and conjunctivitis) preceding the rash. Arthralgia and arthritis are fairly common complications, particularly among adult females. Thrombocytopenia may occur. Encephalitis and hemorrhagic manifestations are rare. [CCDM, p. 527] Adenopathy in postnatal rubella may last for several weeks and commonly affects the posterior cervical, posterior auricular, and suboccipital nodes. The maculopapular rash is not confluent. Fever, if present, usually resolves by the second day of the rash. [PPID, p. 1876-7]
PREVENTION:
Hospitalized or institutionalized patients should be isolated with care taken not to expose pregnant, non-immune employees. Patients should be excused from school or work for 7 days after onset of the rash. 90% of babies are affected with congenital rubella syndrome (deaf, blind, mentally retarded, etc.) when the mothers are infected in the first 10 weeks of pregnancy. [CCDM, p. 531] "Although birth before 1957 is generally considered acceptable evidence of rubella immunity, a dose of MMR has been recommended for those health care personnel that do not have laboratory evidence of immunity." [Guidelines for Infection Control in Health Care Personnel. CDC. 1998] "Any exposed HCP who do not have adequate presumptive evidence of rubella immunity should be excluded from duty beginning 7 days after exposure to rubella and continuing through either 1) 23 days after the most recent exposure or 2) 7 days after rash appears if the provider develops rubella. Exposed HCP who do not have adequate presumptive evidence of immunity who are vaccinated postexposure should be excluded from duty for 23 days after the most recent exposure to rubella because no evidence exists that postexposure vaccination is effective in preventing rubella infection." [ACIP, 2011]
For updated text and symptoms of infectious diseases, see iddx.com.
Diagnostic
IgM ELISA test; Paired sera; PCR positive before IgM antibodies; Rubella is mild disease and difficult to diagnose clinically. [PPID] "The only reliable evidence of previous rubella infection is the presence of serum rubella IgG antibody." [ACIP, 2011]