Behavioral health units (BHU) have been implicated in influenza outbreaks due to group activities, low availability of alcohol-based hand gels and unique host factors. We describe the management of an unusual influenza outbreak, which started in the BHU and then spilled over to the acute care hospital (ACH).
University of Maryland Harford Memorial Hospital is a 95-bed ACH with a 14-bed closed-door adult BHU located on the 5th floor. Two cases each of hospital-acquired influenza were identified in our BHU during 2016 and 2017. In January 2018 however, hospital-acquired influenza cases in the BHU spilled over to the adjacent ACH to cause an outbreak. A case was defined as a patient with fever of >100.4⁰ F, presence of influenza-like illness, and a positive influenza test > 72 hours after admission. Outbreak control measures included twice daily fever screening, enhanced droplet precautions, visitor restrictions, discontinuing community activities, enforcing hand hygiene at all hospital entrances, and hospital-wide chemoprophylaxis with oseltamivir.
On January 15th 2018, the index patient developed influenza in the BHU followed by a second case in BHU 4-days later. Over the next 10 days, 5 more patients on the 3rd and 4th floors of ACH tested positive. Attack rate was 3% and average length of stay was 8.9 days. Chemoprophylaxis with oseltamivir 75mg orally once a day was given to 71% of all eligible hospitalized patients for a week (at a cost of $17,000). All 7 patients yielded influenza A, subtype H3N2 and were successfully treated with oseltamivir 75mg orally twice a day for 7 days. The outbreak lasted 11-days. Figure 1 shows the epidemiologic curve.
Special attention should be paid to influenza prevention in the BHUs due to the risk of spill-over effect to sicker patients in the adjacent ACH. A short, 7-day course of hospital-wide oseltamivir chemoprophylaxis, in addition to promptly implementing the infection prevention measures was effective in controlling the outbreak.
C. M. Clay,
F. Younus, None