Prophylaxis after Exposure to Coxiella burnetii

Postexposure prophylaxis may avert Q fever illness and death when the probability of exposure is above the population-specific threshold point

Antibody response to a sub-potent influenza vaccine among nursing home residents and results of revaccination, New York, 1996-97

Background: In November 1996,11 lots of 1996-97 trivalent influenza vaccine were recalled because of decreasing potency of the A/Nanchang/933/95 (H3N2) component. Since higher antibody liters afford greater protection against influenza and because elderly persons are at high risk of influenza-related complications, we assessed the antibody titers of nursing home residents who received either recalled vaccine (RV) or non-RV. We then assessed the antibody response to revaccination among a subgroup of residents who had first received RV. Methods: We studied 86 residents from 3 nursing homes who received RV and 86 from 3 other nursing homes who received non-RV. Medical records were reviewed and blood samples were obtained 3 weeks after vaccination. Serum was tested by hemagglutination inhibition (HI) for antibody to all 3 components of the 1996-97 influenza vaccine. Sera collected from 23 residents from one nursing home before and 3 weeks after revaccination with normal potency vaccine were also tested by HI. Results: The geometric mean antibody titer (GMT) (33 vs. 55; p =0.01) and the percentage of residents with an antibody tiler >1:40 (52% vs. 67%; p = 0.04) to the A/Nanchang component were lower among residents who received RV than among residents who received non-RV. In the 23 residents assessed for response to revaccination, GMT to the A/Nanchang component increased from 24 to 39 (p=0.01) after revaccination. Conclusions: Residents who received RV had lower post-vaccination antibody titers to A/Nanchang than did those who received non-RV. Revaccination of residents who first received RV was associated with a rise in titer to the A/Nanchang component.Link_to_subscribed_fulltex

Decreased antibody response among nursing home residents who received recalled influenza vaccine and results of revaccination, 1996-97

In November 1996, 11 lots of one U.S. manufacturer's 1996-97 trivalent influenza vaccine were voluntarily recalled because of decreasing potency of the A/Nanchang/933/95 (H3N2) component. Because the elderly are at high risk of developing influenza-related complications, we assessed the postvaccination antibody titers of nursing home residents who received recalled vaccine and assessed the antibody response to revaccination. Blood samples were collected 3 weeks after vaccination from 86 residents at three nursing homes who received recalled vaccine and 86 residents at three other nursing homes who received a different manufacturer's vaccine. Medical records were reviewed. Residents of one nursing home were later revaccinated. Blood samples were collected on the day of revaccination and again in 3 weeks. Serum was tested by hemagglutination inhibition for antibody to all three components of the 1996-97 influenza vaccine. The geometric mean antibody titer (GMT) (33 vs 55; p = 0.01) and the percentage of residents with an antibody titer ≥1:40 (52 vs 67%; p = 0.04) to the A/Nanchang/933/95 component were lower among residents who received recalled vaccine compared to those who received non-recalled vaccine, but had similar GMTs against the other two vaccine components. After revaccination, the GMT to A/Nanchang/933/95 increased from 24 on the day of revaccination to 39 (p = 0.01) in residents from one nursing home. Therefore, vaccination with the recalled vaccine was associated with lower postvaccination antibody titers to A/Nanchang/933/95, but not against the other two vaccine components. Revaccination was moderately effective in increasing antibody titers. With annual changes in influenza vaccine strains, routine post-release stability testing of influenza vaccine should continue.Link_to_subscribed_fulltex