Measles Outbreak:

Details of situation: Five measles cases, four between the ages of 12 to 21 months, have been reported in three different counties within Southeast Texas.

Vaccination remains the most effective method for preventing measles.

Genotyping has revealed the cases were B3 strain, the most common strain currently circulating in Mexico and the second most common strain seen in Canada and the US. The current vaccine, which contains strain A, is effective against B3 and has demonstrated a high protection rate (95-98% seroconversion with the first dose and 99% with the second dose). One of the cases was an adult linked to one of the infant cases.

Measles is highly contagious and early identification remains a critical public health measure to reduce the spread of the disease.

Clinical information: Measles (rubeola) is a highly contagious febrile rash illness caused by
a paramyxovirus transmitted via the respiratory route. The incubation period averages 10-12 days from exposure to prodrome and 14 days from exposure to rash onset (range 7-18 days). The prodrome generally lasts 2-4 days and is characterized by fever, increasing in stepwise fashion and often peaking at 103°-105°F.

Fever is followed by the onset of cough, coryza, and/or conjunctivitis. Koplik spots, while not always present, and appear as blue/white spots on the bright red background of the buccal mucosa, occurring 1-2 days before rash to 1-2 days afterwards. The measles rash begins at the hairline and gradually proceeds to face and upper neck and from there downward and outward.

Other symptoms of measles include anorexia, diarrhea (especially in infants), Complications can include otitis media, pneumonia, encephalitis, seizures and death. While it is rare that vaccinated individuals develop measles, it can happen. Vaccinated individuals may have an atypical clinical presentation—typically shorter rash duration or atypical rash presentation, and possible lack of fever, cough, coryza or conjunctivitis.

In Texas, suspicion of measles is required to be reported immediately. Do not wait for laboratory confirmation to report measles.

Measles reports should be made to the local health department or 800-705-8868. Infection Control: Patients are contagious from 4 days before onset of rash to 4 days after appearance of rash (day of rash onset is day 0).

If someone has these symptoms, isolate the patient with airborne isolation precautions, if possible and call the MD office before arrival for instructions prior to arrival at office.

People suspected of having measles should be advised to stay home from work, school, daycare, and any public outings (e.g., church, grocery store) until four days after rash onset have passed.