PspA is a cell surface protein of Streptococcus pneumoniae that is present on a number of clinical isolates as well as the nonencapsulated laboratory strain Rx1. In a previous report we have shown that mAbs directed against PspA can protect mice from at least some of the pneumococcal strains bearing this protein. In our present report we have produced insertional inactivation mutants that lack PspA and have used these mutants to demonstrate that PspA can play a role in pneumococcal virulence and that anti-PspA immunity can lead to protection against pneumococcal infection. PspA- mutants were obtained using derivatives of plasmid pVA891 carrying chromosomal fragments from Rx1. From one of the mutants, we cloned a 550 bp fragment of the pneumococcal gene into pVA891 and transferred this chimeric plasmid, designated pKSD300, into Escherichia coli. After transformation of pKSD300 into Rx1, PspA production is not detected. In colony hybridization experiments, the 550 bp fragment hybridizes specifically to pneumococcal isolates in a pattern consistent with the hypothesis that the fragment is a portion of the pspA structural gene that is different from the portions coding for the antigenic determinants detected by mAbs Xi64 or Xi126. When X-linked immunodeficient (xid) CBA/N mice were immunized with wild-type Rx1, they were resistant to challenge with type 3 strain WU2. However, when these mice were immunized with a PspA- mutant of Rx1, they failed to survive the subsequent challenge, indicating that immunity to PspA can contribute to the resistance to pneumococcal infection. Using pKSD300 we insertionally inactivated pspA in D39, a virulent strain of S. pneumoniae. When injected intravenously there was a 10-fold greater reduction of the mutant pneumococci in the blood, as compared to the wild-type D39.

• Annual total direct and indirect costs related to infections with the hepatitis C virus (HCV) in the United States were estimated at $5.46 billion in 1997. Davis et al. (2011) estimated that all-cause health care costs for managed care organization (MCO) enrollees with HCV were $20,961 per patient per year (PPPY), of which $6,864 PPPY was HCV-related, from 2002 through 2006.• The burden of illness for HCV is predicted to grow over the next 2 decades, partly due to increased prevalence of advanced liver disease (AdvLD) in the current HCV population. What is already known about this subjectAll-Cause and METHODS: This retrospective, matched cohort study included patients aged at least 18 years and with at least 6 months of continuous enrollment in a large managed care organization (MCO) claims database from July 1, 2001, through March 31, 2010. Patients with a diagnosis of HCV (ICD-9-CM codes 070.54, 070.70) were identified and stratified into those with and without AdvLD, defined as decompensated cirrhosis (ICD-9-CM codes 070. 44, 070.71, 348.3x, 456.0, 456.1, 456.2x, 572.2, 572.3, 572.4, 782.4, 789.59); hepatocellular carcinoma (HCC, ICD-9-CM code 155); or liver transplant (ICD-9-CM codes V42.7, 50.5 or CPT codes 47135, 47136). For patients without AdvLD, the index date was the first HCV diagnosis date observed at least 6 months after the first enrollment date, and at least 6 months of continuous enrollment after the index date were required. HCV patients without AdvLD were stratified into those with and without compensated cirrhosis (ICD-9-CM codes 571.2, 571.5, 571.6). For patients with AdvLD, the index date was the date of the first AdvLD diagnosis observed at least 6 months after the first enrollment date, and at least 1 day of enrollment after the index date was required. Cases were matched in an approximate 1:10 ratio to comparison patients without an HCV diagnosis or AdvLD diagnosis who met all other inclusion criteria based on gender, age, hospital referral region state, pre-index health care costs, alcoholism, human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), and a modified Charlson Comorbidity Index. For the HCV and comparison patient cohorts, PPPY all-cause costs to the payer were calculated as total allowed charges summed across all patients divided by total patient-days of follow-up for the cohort, multiplied by 365, inflation-normalized to 2009 dollars. Because the calculation of PPPY cost generated a single value for each cohort, bootstrapping was used to generate descriptive statistics. Incremental PPPY costs for HCV patients relative to non-HCV patients were calculated as between-group differences in PPPY costs. T-tests for independent samples were used to compare costs between case and comparison cohorts.RESULTS: A total of 34,597 patients diagnosed with HCV, 78.0% with HCV without AdvLD, 4.4% with compensated cirrhosis, 12.3% with decompensated cirrhosis, 2.8% with HCC, and 2.6% with liver transplant, were matched to 330,435 comparison patients. Mean (SD) age of al...

Recent research has identified high hepatitis C virus (HCV) prevalence among older U.S. residents who contracted HCV decades ago and may no longer be recognized as high risk.We assessed the cost-effectiveness of screening 100% of U.S. residents born 1946-1970 over 5 years (birth-cohort screening), compared with current risk-based screening, by projecting costs and outcomes of screening over the remaining lifetime of this birth cohort. A Markov model of the natural history of HCV was developed using data synthesized from surveillance data, published literature, expert opinion, and other secondary sources. We assumed eligible patients were treated with pegylated interferon plus ribavirin, with genotype 1 patients receiving a direct-acting antiviral in combination. The target population is U.S. residents born 1946-1970 with no previous HCV diagnosis. Among the estimated 102 million (1.6 million chronically HCV infected) eligible for screening, birth-cohort screening leads to 84,000 fewer cases of decompensated cirrhosis, 46,000 fewer cases of hepatocellular carcinoma, 10,000 fewer liver transplants, and 78,000 fewer HCV-related deaths. Birth-cohort screening leads to higher overall costs than risk-based screening ($80.4 billion versus $53.7 billion), but yields lower costs related to advanced liver disease ($31.2 billion versus $39.8 billion); birth-cohort screening produces an incremental costeffectiveness ratio (ICER) of $37,700 per quality-adjusted life year gained versus riskbased screening. Sensitivity analyses showed that reducing the time horizon during which health and economic consequences are evaluated increases the ICER; similarly, decreasing the treatment rates and efficacy increases the ICER. Model results were relatively insensitive to other inputs. Conclusion: Birth-cohort screening for HCV is likely to provide important health benefits by reducing lifetime cases of advanced liver disease and HCV-related deaths and is cost-effective at conventional willingness-topay thresholds. (HEPATOLOGY 2012;55:1344-1355 H epatitis C virus (HCV) is the most common blood-borne viral infection in the United States, 1 affecting an estimated 3.6 million U.S. residents.2 The majority of infected individuals develop chronic hepatitis; persistent liver injury leads to cirrhosis in 5%-30% of cases 3 and may progress to advanced liver disease (AdvLD), which includes decompensated cirrhosis or hepatocellular carcinoma (HCC), leading to liver transplant and premature death. Costs of HCV in the United States are estimated to exceed $5 billion per year, 4 with projected HCV-related societal costs for the years 2010-2019 estimated to total $54.2 billion. 5For the last decade, the standard of care for treating HCV has been the combination of pegylated interferon (Peg-IFN) and ribavirin (RBV), 6 which successfully eradicates virus (sustained virologic response; SVR) in 40%-80% of treated patients. 7 This response is 40%-50% in patients with HCV genotype 1 and 80% for patients infected with HCV genotypes 2 and 3. However, the rece...

The economic burden of TBI in the acute-care setting is substantial; treatment outcomes and costs vary considerably by TBI severity and mechanism of injury.