Date of Award


Document Type


Degree Name

Medical Doctor (MD)

First Advisor

Kirsten Bechtel, MD

Second Advisor

Mark X. Cicero, MD


Fever in infants younger than 2 months of age causes a significant number of emergency department visits and is particularly worrisome because of the potential for serious infection. Management of febrile infants is problematic because clinical observation is not a reliable indicator of serious bacterial illness (SBI), such as bacteremia, meningitis, and urinary tract infection (UTI). Numerous investigators have proposed methods of screening laboratory tests to ascertain the risk of SBI in febrile infants. These screening tests could potentially avoid the invasive and costly sepsis work-up, which usually includes complete blood count (CBC), blood culture, urinalysis, urine culture, and lumbar puncture. We conducted a prospective, cross-sectional study that examined the prevalence of rhinovirus (RV) and coronavirus (CoV), which are two of the most common causes of upper respiratory infections in the first year of life, and human metapneumovirus (hMPV), which is a common cause of bronchiolitis, in infants younger than 2 months of age. This study also examined whether febrile infants with RV were more or less likely to also have a SBI than infants without a viral respiratory infection. Methodology: Fever was defined as rectal temperatures greater than 37.9C or a historical fever greater than 100.3F. Nasal swabs were tested with reverse transcriptase polymerase chain reaction (rt-PCR) techniques for rhinoviruses (RV), human metapneumovirus (hMPV) and coronaviruses (CoV). Nasal samples were also tested for RSV, influenza A and B, parainfluenza types 1, 2 and 3, and adenovirus via direct fluorescent antibody (DFA). Conclusion: Rhinovirus (RV) was the most commonly detected respiratory viral pathogen in our cohort (14% out of 98 total enrolled patients). Coronovirus (CoV) and human metapneumovirus (hMPV) were both detected but in only one patient (1%) each. RV occurred predominantly in the summer (79%). This cohort of patients showed no difference between the incidence of serious bacterial illness (SBI) with and without RV infection (p=0.84).


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