The BIG- LoVE study (Utah- Better Identification of Germs-Longitudinal Viral Epidemiology)- kudos for the catchy acronym, rather clever indeed, especially from a state (Utah) with a prior history of polygamy.The article can be accessed here and was published in Clinical Infectious Diseases.
The investigators assessed the viral etiology of respiratory
illness by prospectively collecting weekly symptom diaries and nasal swabs for PCR analysis from
families for 1 year, analyzed data by reported symptoms, virus, age, and
family composition, and evaluated the duration of virus detection.
Twenty-six households (108 individuals) provided concurrent
symptom and nasal swab data for 4166 person-weeks.
Participants reported symptoms in 23% and a virus was
detected in 26% of person-weeks. There were 783 viral detection episodes; 440 (56%) associated
with symptoms. Coronaviruses, human metapneumovirus, and influenza A. Viral detections
were usually symptomatic; bocavirus and rhinovirus detections were often
asymptomatic. The mean duration of PCR detection was ≤2 weeks for all viruses
and detections of ≥3 weeks occurred in 16% of episodes. Younger children had
longer durations of PCR detection.
So viral detection is common and often asymptomatic. Again, we need to resist using anti-infectives when not warranted. If it is not Influenza- no oseltamavir. Also, if the the clinical presentation is of a viral upper respiratory infection, no antibiotics!
Eventually we will need better diagnostics, one that can detect pathogens and the concomitant inflammatory response, to differentiate between infection versus asymptomatic shedding.
