Impact of influenza vaccination on seasonal mortality in the US elderly population

BACKGROUND: Observational studies report that influenza vaccination reduces winter mortality risk from any cause by 50% among the elderly. Influenza vaccination coverage among elderly persons (> or =65 years) in the United States increased from between 15% and 20% before 1980 to 65% in 2001. Unexpectedly, estimates of influenza-related mortality in this age group also increased during this period. We tried to reconcile these conflicting findings by adjusting excess mortality estimates for aging and increased circulation of influenza A(H3N2) viruses. METHODS: We used a cyclical regression model to generate seasonal estimates of national influenza-related mortality (excess mortality) among the elderly in both pneumonia and influenza and all-cause deaths for the 33 seasons from 1968 to 2001. We stratified the data by 5-year age group and separated seasons dominated by A(H3N2) viruses from other seasons. RESULTS: For people aged 65 to 74 years, excess mortality rates in A(H3N2)-dominated seasons fell between 1968 and the early 1980s but remained approximately constant thereafter. For persons 85 years or older, the mortality rate remained flat throughout. Excess mortality in A(H1N1) and B seasons did not change. All-cause excess mortality for persons 65 years or older never exceeded 10% of all winter deaths. CONCLUSIONS: We attribute the decline in influenza-related mortality among people aged 65 to 74 years in the decade after the 1968 pandemic to the acquisition of immunity to the emerging A(H3N2) virus. We could not correlate increasing vaccination coverage after 1980 with declining mortality rates in any age group. Because fewer than 10% of all winter deaths were attributable to influenza in any season, we conclude that observational studies substantially overestimate vaccination benefit.     

Clinical and diagnostic comparison of neonatal alloimmune thrombocytopenia to non-immune cases of thrombocytopenia

BACKGROUND: Affected patients with neonatal alloimmune thrombocytopenia (AIT) are often severely thrombocytopenic and, if so, may suffer an intracranial hemorrhage (ICH). This study was undertaken to compare the outcome of cases of AIT to cases of neonatal thrombocytopenia shown not to be AIT and to identify clinical features that would facilitate the diagnosis. PROCEDURE: Two hundred twenty two cases of neonatal thrombocytopenia for which serologic testing was obtained by the referring physician were accrued for this study from 11 testing laboratories. The relevant clinical information was pursued. RESULTS: The mean birth platelet count in 110 neonates with AIT was 26,000/mm(3) x 10(9)/L and the rate of ICH was 11% (not all neonates had head sonos). Three criteria distinguished cases of AIT from other causes of neonatal thrombocytopenia (n = 56): (1) severe thrombocytopenia <50,000/mm(3) x 10(9)/L; (2) ICH associated with 1 or more of: a 1-min Apgar score >5, birthweight >2,200 g, grade >1, antenatal occurrence, or signs of bleeding, that is, petechiae, ecchymoses; and (3) no additional, non-hemorrhagic neonatal medical problems. CONCLUSIONS: AIT is a unique type of neonatal thrombocytopenia with significant hemorrhagic consequences. Identification of AIT at the bedside should guide institution of appropriate treatment and lead to serologic testing for confirmation.     

Impact of insertions in the HIV-1 p6 PTAPP region on the virological response to amprenavir

We evaluated the impact of genetic changes within p6Gag gene on the virological response (VR, mean decrease in plasma viral load at week 12) to unboosted amprenavir (APV). Gag-protease fragments, including gag p2, p7, p1, p6 regions and whole protease (PR) were sequenced from baseline plasma specimens of 84 highly pre-treated but APV-naive patients included in the NARVAL (ANRS 088) trial. The correlation between baseline p6Gag polymorphism, PR mutations, baseline characteristics and VR to APV was analysed in univariate analysis. Insertions (P459Ins) within p6 protein, leading to partial or complete duplication of the PTAPP motif, were significantly associated with a decreased VR (P459Ins versus wild-type; -0.3 +/- 0.8 vs -1.1 +/- 1.2 log copies/ml, P=0.007) and were more frequent when the V82A/F/T/S PR mutation was present (P=0.020). In multivariate analysis, after adjustment on the predictive factors of the VR in the NARVAL trial and on the PR mutations linked with response, there was a strong trend to an association (P=0.058) between the presence of P459Ins and an altered VR. In conclusion, these results suggest that insertions in the p6 region of HIV-1 gag gene may affect the VR, in highly pre-treated patients receiving an unboosted APV-containing regimen.     

Physiologic-insensitive left ventricular assist predisposes right-sided circulatory failure: a pilot simulation and validation study

Right-sided circulatory failure (RSCF) is a serious complication in 15-30% of patients receiving a left ventricular assist device (LVAD). It is hypothesized that left ventricular support which lacks physiologic properties predisposes to RSCF. An integral computer simulation and experimental validation protocol was performed. The results suggest that with conventional insensitive left ventricular support right-sided circulatory function is compromised, which may form a substrate for the onset or progress of RSCF. Feedback control of the LVAD could provide a means to counter this problem. A control concept for the LVAD which aims to preserve right-sided circulatory function, while supporting peripheral perfusion, is proposed     

A review of preschool vision screening for strabismus and amblyopia in France: 23 years experience in the Alsace region

The authors report their experience in preschool vision screening in the east of France, involving the Mother and Child Welfare Service and the School Health Service, under the administration of the National Ministry of Education. The review underlines the importance of early diagnosis of visual disorders in children before they reach three years of age. They recommend screening of every child at least once before the age of four years.