by Michael Smith
Healthcare workers in a New York City emergency department had the highest rate of infection among employees of an urban hospital system during the first wave of the H1N1 pandemic flu, researchers said.
In a single-institution study using medical and administrative records, the adult emergency department had an H1N1 infection rate of 28.8% during April, May, and June of 2009, according to Robert Bristow, MD, and colleagues at New York-Presbyterian Hospital.
The pediatric emergency department was close, with an infection rate of 25%, Bristow and colleagues reported in the March issue of Disaster Medicine and Public Health Preparedness.
Nearly half of the reported cases of H1N1 in healthcare workers — 49% — occurred in emergency medicine, pediatrics, ambulatory care, intensive care units, and anesthesiology, the researchers found.
Those departments accounted for only 19.1% of the healthcare workers analyzed in the study, which included 6,093 New York-Presbyterian Hospital employees from two university medical centers, a freestanding pediatric hospital, a community hospital, and a behavioral health facility.
Bristow and colleagues are studying the impact of the pandemic flu on healthcare workers before and after the availability of the H1N1 vaccine. The current analysis is the first phase of the study.
The researchers compared 2009 absenteeism records with those from 2007 and 2008 to gauge the impact of the flu on the hospital as a whole.
Workers were categorized into six general groups — 506 physicians and medical personnel, 1,634 nurses and clinical technicians, 294 social workers and counselors, 295 housekeeping and food service employees, 77 security and patient transportation personnel, and 3,287 administrative and technical support services staffers.
They also focused on the 1,190 workers in seven departments thought to be at greatest risk: 52 in the adult emergency department, 20 in the pediatric emergency department, 353 in general pediatrics, 21 in workforce health and safety, 504 in ambulatory care, 195 in intensive care units, and 45 in anesthesiology.
They found:
* On average, sick hours for all workers in April through June increased by 10.5% over the same period in 2008 and by 9.7% over 2007. Both differences were significant at P<0.001.
* There was little increase in April, compared with previous years, but significant increases (all at P<0.001) both in May and June. The greatest increases came in June — 23.7% compared with 2008 and 21.2% compared with 2007.
* Altogether, 123 laboratory-confirmed cases were observed.
* Physicians and medical personnel were hardest-hit, with 34 cases, or 6.7% of the total in the category. Nurses and clinical technicians saw 36 cases, or 2.2% of the people in that group.
Interestingly, there is some evidence that some personnel may have worked through their illnesses, the researchers said.
For example, physicians and medical personnel experienced a 13.3% increase in sick hours during June and had the highest infection rate of laboratory-confirmed H1N1. But in May, they recorded a 21.8% decrease in mean sick hours.
Largely because of variation in sick hours within the category, Bristow and colleagues said, the differences from the two previous years were not significant.
The implication, they said, is that “although there were many cases of infection within the physicians and medical personnel category, a sufficient proportion of the employees still reported to duty and may have worked despite illness during this period.”
The researchers cautioned that the observed differences in absenteeism could have been caused by factors other than H1N1 infection. Other factors — such as leave policies, individual incomes, and flexibility in scheduling hours — may also have affected the ability of an employee to stay home when sick.
Differences in the likelihood of being tested for H1N1, they said, also could have influenced the results.
Michael Smith is a MedPage Today North American Correspondent.
Originally published in MedPage Today. Visit MedPageToday.com for more hospital news.
