Respiratory Viruses: A View of Future Pandemics

Abstract & Commentary

By Dean L. Winslow, MD, Chief, Division of AIDS Medicine, Santa Clara Valley Medical Center; Clinical Professor, Stanford University School of Medicine, is Associate Editor for Infectious Disease Alert.

Dr. Winslow serves as a consultant for Siemens Diagnostics, and is on the speaker's bureau for Boehringer-Ingelheim and GSK.

Synopsis: Healthcare workers who had been actively involved in SARS work were more "positive" in responding to an impending avian influenza epidemic.

Sources: Tam DK, et al. Impact of SARS on avian influenza preparedness in healthcare workers. Infection. 2007;35:320-325; Imai T, et al. SARS risk perceptions in healthcare workers, Japan. Emerg Infect Dis. 2005;11:404-410; Koh D, et al. SARS: Health care work can be hazardous to health. Occup Med (Lond). 2003;53:241-243.

The perception of health care risks motivates behaviors in healthcare workers as well as patients.3 Several years after the SARS outbreak in China and Hong Kong, Japanese industrial scientists found that healthcare workers had a high perception of risk for SARS manifest primarily by a desire to avoid patients.2 At the same time these workers had a low acceptance of risk and felt little personal control. These workers' perceptions were not associated with poor knowledge of preventive measures. Indeed, the workers had a high sense of fear because they felt preventive measures were not effective. When job category was considered, nurses ranked the highest for perception of risk. With regard to gender, women had higher indices of fear than men. Older age correlated with less perception of fear.

Now, two years later comes an article from Hong Kong, an area that was an epicenter of the SARS epidemic. The authors did not ask questions about SARS preparedness and the fear therein, but asked questions about a more contemporary perceived threat, avian influenza.1 The questionnaire modified from one used previously for SARS perceptions was administered in Chinese to 2929 healthcare workers; 999 questionnaires were available for analysis, most from nurses (84.3%). About 30% of respondents had experience in SARS outbreaks. What stood out in the results was the association between the experience with SARS and the sense of needing to remain vigilant for avian influenza. Nurses with experience with SARS were more likely to avoid patients suspected of having avian influenza. The same nurses were less likely to want a change in their job. The nurses who had frequent recall of their SARS experience were the ones more likely to be afraid of becoming ill with avian influenza. A SARS recall on the part of the health care worker did not relate to a positive acceptance of acquiring avian influenza as part of the job, whereas, subjects with SARS recall were slightly, but significantly more likely (54.6 vs 46.8%) to believe there would be a avian influenza outbreak in Hong Kong.

Commentary

Most of the data from this survey support the idea that SARS in Hong Kong better prepared the healthcare society to approach a hypothetical influenza pandemic. While there may have been sampling errors, as the authors caution, this setting was a unique attempt to sample the sense of risk when no standardized instrument exists "to measure attitude and risk perception of health care workers towards an impending avian influenza outbreak."

With this study we move into rarefied level of inquiry: how does memory affect our willingness to provide healthcare? It is known that traumatic memories can affect our behavior, but there is little study of such memories on healthcare delivery. Thus, we have a paradox between the Japanese observation of anxiety about SARS among healthcare workers who had no actual exposure to SARS and the greater acceptance of risk with regard to an acute respiratory pathogen by Hong Kong workers who actually had exposure to SARS.

An American explanation to this paradox may be, well, if you escaped once you have a good chance of escaping again. Still the real reasons may have deeper cultural roots. Indeed the cultural differences among the SARS-unaffected Japanese and SARS affected Chinese may be profound, thus the reason that more studies like this one by Tam et al need repeated in various countries, perhaps with contrasting experiences to other pathogens. For example are nurses with experience with HIV patients more likely to have less anxiety caring for patients with hepatitis C? Are physicians who worked in leper colonies more likely to risk their lives in subsequent exposures to potentially fatal infections? Perhaps the experience with Ebola in Uganda would be another area of study.

These current investigations were not easy to perform and recruitment of subjects can be difficult. In Tam's study only about a fourth of questionnaires were ultimately returned, most of these being from nurses. New studies need pursue a higher enrollment of more physicians, pharmacists and allied healthcare workers so that we can understand the psychologic dynamics among those groups and develop strategies based on the group's response to both perceived and real past exposures.

Physicians, infectious diseases specialists and infection control professionals need to understand these evolving dynamics of anxiety in healthcare workers. Understanding their fear can help us better address the basic infection control issues of isolation, handwashing and other protective measures during epidemics and pandemics.