Emergency department visits and infections

We thank Dr. Platts-Mills and Dr. Sloane for their comments1 — and we agree, as stated in the conclusion of our article, that “confirmation of these results with studies of specific types of infection with laboratory testing is required.”2 We included only residents of long-term care facilities who received an emergency department discharge diagnosis other than a respiratory or a gastrointestinal infection. We screened charts of emergency departments and long-term care facilities to exclude patients with symptoms of these illnesses before or during their emergency department visit.

Although many think that residents of long-term care facilities may be more likely to have atypical presentations of infections, Berman and colleagues3 showed that “in most elderly patients who develop infection, there remain clear clinical pointers to the diagnosis. The symptoms may be absent or unreliable but the physical signs remain.” In our study population, the onset of symptoms started on average 4.1 days (median 3.5) after residents returned from the emergency department, which is the typical incubation period for respiratory and gastrointestinal infections following an exposure.4

Moreover, if a resident exposed to the emergency department were incubating a respiratory or gastrointestinal infection at the time of exposure, we would have expected that transmission to also have occurred at the resident’s unit in the long-term care facility. Two randomly chosen residents were matched by the unit or ward in the same long-term care facility and on the index date (return date of one resident from the emergency department). If the returning resident had been exposed in the long-term care facility before presenting to the emergency department, the resident who did not visit the emergency department would have the same chance of exposure, thus decreasing the strength of the association found.

The finding of our study is biologically plausible and is in keeping with the increased risk described by Troko and colleagues.5 They reported that use of a bus or tram within five days of symptom onset was associated with an almost sixfold increased risk of consulting for acute respiratory infections (adjusted odds ratio = 5.94, 95% confidence interval 1.33–26.5).

We agree with Dr. Platts-Mills and Dr. Sloane that emergency departments and hospitals are important sites of care for residents of long-term care facilities. Care in these sites is not necessarily free of adverse events and can be improved. We hope that the results of our study will stimulate other investigators to confirm or refute our findings, and support staff in emergency departments as they work to ensure the safest possible environment for all the patients in their care.