Development of a novel nasal lavage device to obtain nasopharyngeal mucus samples for viral identificaion in infancy

To develop a patient-acceptable technique for nasal lavage (NL) during infancy to identify viral pathogens producing wheezing illnesses. In prospective epidemiologic evaluations, a major drawback to the standard Dacron tipped swab method used for the procurement of nasal mucus samples for viral culture is the development of patient and parental intolerance for the procedure. Therefore, we developed a novel device for NL by creating a soft tip to insert into the child's nares, a syringe to aggressively wash the membrane with saline (thus dislodging cells), and a means to aspirate and collect the sample. Using this device during infancy, overall positive viral identification by culture and PCR was obtained in 72% (414/578) samples in children with symptom scores of >=5. Of these, viral recovery rates were highest 78% (69/88) of children with significant (score >10) lower respiratory tract illnesses and in children with scores of 5-10, virus was detected in 70% (345/490) of the samples. With minimal illness (score 1-4), virus was detected in 47% (97/215) of the samples and detected 10% (89/893) of the time in infants with no symptoms. Familial acceptance of the procedure was excellent, with many parents requesting to keep the device to use for clearance of upper respiratory tract secretions. In a seven year prospective birth cohort study (COAST) to evaluate genetic and environmental factors underlying asthma inception, the development and use of this nasal lavage device, instead of the nasal swab, has facilitated repetitive specimen collection and viral identification without impairing subject retention.