Clinical Features of Pediatric Patients Undergoing Measles Testing During Outbreaks in Orange County, CA – What Should We Be Looking and Testing For?
Measles is a highly contagious airborne transmissible viral infection. Orange County, CA experienced outbreaks in 2014 and 2015. During these outbreaks, 76 pediatric patients were tested for measles by two pediatric emergency departments or local public health.
Demographic, clinical and laboratory data for pediatric patients tested for measles were collected and analyzed. All measles testing (serum IgM, nasopharyngeal or throat and urine polymerase chain reaction (pcr)) was performed by the public health lab. Patient samples that tested negative for measles were later screened for influenza by pcr.
Five patients were excluded from analysis due to recent vaccination (2), lack of symptoms (1), or missing data (2). Measles was confirmed in 17 and ruled out in 54 patients. Mean age of cases was 3 years (range 3 months – 16 years). Eight of 17 (47%) cases were hospitalized for a mean of 2.9 days. Receipt of at least 1 dose of MMR vaccine was associated with negative measles testing (OR 0.05, p<0.001). Only one measles case had received a measles vaccine. The presence of fever beginning at least one day prior to onset of rash, combined with specific features such as respiratory symptoms (cough, congestion, rhinorrhea, or conjunctivitis), and rash starting on the face and descending, progressively distinguished cases from controls (Figure 1 ). Six of 54 (11%) of measles negative samples were found to be positive for influenza; 5 were type A and 1 type B.
During these outbreaks, the presence of preceding fever, rash that started on the face and descended, and respiratory symptoms were associated with confirmed measles in children. Screening unimmunized children for classic measles signs and symptoms, rather than just fever and rash, would quickly identify most cases of measles during outbreaks, allowing for more streamlined testing and prompt implementation of appropriate infection control precautions. Testing for other respiratory pathogens circulating in the community, particularly influenza, may be beneficial given the overlap in symptoms.
M. Cheung, None
D. Nieves, None
N. Ashouri, None
F. C. Adler-Shohet, None
M. Zahn, None