An outbreak of influenza A occurs in the community, and a case has just been confirmed at a nursing home. Three additional residents with a flulike illness are identified in the same facility. The nursing home plans to institute measures to prevent further spread of the infection.
Which of the following measures is most likely to have the highest impact in reducing the number of new influenza cases at the facility during this outbreak?

Question

An outbreak of influenza A occurs in the community, and a case has just been confirmed at a nursing home.  Three additional residents with a flulike illness are identified in the same facility.  The nursing home plans to institute measures to prevent further spread of the infection.
Which of the following measures is most likely to have the highest impact in reducing the number of new influenza cases at the facility during this outbreak?

Quizplus · Accepted Answer

11ec193a_9848_fb9a_853d_93456c585ece_MD0002_00 During influenza season, when >2 residents of a health care facility develop a flulike illness within 72 hours of each other, influenza testing should take place. If the diagnosis of influenza is confirmed, initiation of prompt prophylactic antiviral therapy for all residents (whether vaccinated or not and regardless of ward/floor) provides the best chance of reducing additional influenza cases within the facility. This approach is recommended by the United States Advisory Committee on Immunization Practices and the Infectious Diseases Society of America. Unvaccinated employees should also receive chemoprophylaxis. The type of chemoprophylaxis will depend on the characteristics of the virus, but the usual recommended agent is oseltamivir or zanamivir. Prophylaxis should be continued for 14 days or for 10 days after the onset of illness in the last person infected, whichever is longer. Health care workers who are ill or suspected to have contracted influenza should not report to work until 24 hours after symptom resolution. (Choice A) Contact isolation alone is not sufficient in cases of influenza; droplet isolation is also required. In addition, although instituting droplet and contact precautions will help reduce the spread of influenza, it is not as effective as chemoprophylaxis of all residents. (Choices B and C) Nearly 60% of long-term care employees currently receive annual influenza vaccination, and mandatory vaccination programs can increase this rate further. However, it could take up to 15 days after vaccination for a significant vaccine response. Furthermore, influenza vaccine efficacy is suboptimal in the elderly, and outbreaks have occurred even in facilities where 98% of residents were vaccinated. Prophylactic chemotherapy will have a higher impact in controlling the current outbreak. (Choice D) Compared to chemoprophylaxis, limiting access of symptomatically ill staff or visitors is likely less effective in reducing the number of new influenza cases, especially given that viral shedding and transmission can occur prior to symptom onset. Educational objective: Identification of cases of influenza within a long-term care facility should prompt early institution of prophylactic antiviral therapy to all residents (even those previously vaccinated) during the outbreak. __________ References: Antiviral agents for the treatment and chemoprophylaxis of influenza --- recommendations of the Advisory Committee on Immunization Practices (ACIP). (http://www.ncbi.nlm.nih.gov/pubmed/21248682) Importance of employee vaccination against influenza in preventing cases in long-term care facilities. (http://www.ncbi.nlm.nih.gov/pubmed/21931249)

An Outbreak of Influenza a Occurs in the Community, and a Case