The measles virus is an RNA paramyxovirus.9 The primary site of infection is the respiratory epithelium of the nasopharynx. The virus is spread from four days before to four days after a rash appears primarily by airborne droplets and droplet nuclei generated by an infected person during talking, breathing, coughing, and sneezing; by direct contact with nasal or throat secretions from; and less frequently by touching freshly contaminated articles and environmental surfaces.
Signs and symptoms of measles generally begin 7 to 14 after exposure. A typical case is characterized by malaise (feeling run down, achy); fever ≥101.0°F (≥38.3°C); coughing, coryza (runny nose), and conjunctivitis (red, watery eyes); followed by a generalized rash lasting ≥3 day. Bluish-white Koplik spots of the buccal mucosa, which may occur from 1 to 2 days before to 1 to 2 days after the rash are considered pathognomonic for measles.
Measles is a vaccine-preventable disease and measles infection confers life-long immunity. In the absence of acceptable presumptive evidence of immunity, following exposure active immunization is highly recommended. Prevaccination antibody testing of HCP is not necessary. While separate monovalent formulation vaccines for measles, mumps, and rubella are available, the trivalent MMR vaccine is the vaccine of choice for routine adult vaccination.
There is no specific antiviral therapy for measles. Medical care is supportive to help relieve symptoms and to address complications such as bacterial infections. If HCP without evidence of immunity are exposed to measles, MMR vaccine should be given within 72 hours or immunoglobulin within 6 days when available. HCP without evidence of immunity should be excluded from duty from day 5 after first exposure to day 21 after last exposure.