Bacterial contamination of saline nasal spray/drop solution in patients with respiratory tract infection

This study evaluated the potential for bacterial contamination of saline nasal spray/drop solution after 3 days of clinical use in patients. Twenty patients with upper respiratory infection used the saline as a spray, and 20 patients used the solution as drops. Bacterial growth was present in 18 (907%) solution containers of the spray group and in 3 (157%) solution containers of the drops group (P <.005). Twenty isolates were recovered from the spray group and 3 from the drops group. The predominate isolates included Staphylococcus aureus, Staphylococcus epidermidis, alpha Streptococcus species, Pseudomonas aeruginosa, Escherichia coli, and Proteus spp. This study demonstrates the contamination of nasal saline-dispensing solution used as a spray with micro-organisms that are part of the normal skin and nasal flora and gram-negative organisms of potential enteric origin. These data support the use of nasal saline-dispensing solution as drops, rather than as spray. They also illustrate the risk for crossinfection if a nasal solution is used by more than 1 patient.