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Contains fulltext : 225281.pdf (Publisher’s version ) (Closed access) Contains fulltext : 225281pos.pdf (Author’s version postprint ) (Open Access) BACKGROUND & AIMS: Polycystic liver diseases (PLDs) are genetic disorders characterized by progressive development of multiple biliary cysts. Recently, novel PLD-causative genes, encoding for endoplasmic reticulum (ER)-resident proteins involved in protein biogenesis and transport, were identified. We hypothesized that aberrant proteostasis contributes to PLD pathogenesis, representing a potential therapeutic target. METHODS: ER stress was analysed at transcriptional (qPCR), proteomic (mass spectrometry), morphological (transmission electron microscopy, TEM) and functional (proteasome activity) levels in different PLD models. The effect of ER stress inhibitors [4-phenylbutyric acid (4-PBA)] and/or activators [tunicamycin (TM)] was tested in polycystic (PCK) rats and cystic cholangiocytes in vitro. RESULTS: The expression levels of unfolded protein response (UPR) components were upregulated in liver tissue from PLD patients and PCK rats, as well as in primary cultures of human and rat cystic cholangiocytes, compared to normal controls. Cystic cholangiocytes showed altered proteomic profiles, mainly related to proteostasis (ie synthesis, folding, trafficking and degradation of proteins), marked enlargement of the ER lumen (by TEM) and hyperactivation of the proteasome. Notably, chronic treatment of PCK rats with 4-PBA decreased liver weight, as well as both liver and cystic volumes, of animals under baseline conditions or after TM administration compared to controls. In vitro, 4-PBA downregulated the expression (mRNA) of UPR effectors, normalized proteomic profiles related to protein synthesis, folding, trafficking and degradation and reduced the proteasome hyperactivity in cystic cholangiocytes, reducing their hyperproliferation and apoptosis. CONCLUSIONS: Restoration of proteostasis in cystic cholangiocytes with 4-PBA halts hepatic cystogenesis, emerging as a novel therapeutic strategy.

Loss of protein folding homeostasis features many of the most prevalent neurodegenerative disorders. As coping mechanism to folding stress within the endoplasmic reticulum (ER), the unfolded protein response (UPR) comprises a set of signaling mechanisms that initiate a gene expression program to restore proteostasis, or when stress is chronic or overwhelming promote neuronal death. This fate-defining capacity of the UPR has been proposed to play a key role in amyotrophic lateral sclerosis (ALS). However, the several genetic or pharmacological attempts to explore the therapeutic potential of UPR modulation have produced conflicting observations. In order to establish the precise relationship between UPR signaling and neuronal death in ALS, we have developed a neuronal model where the toxicity of a familial ALS-causing allele (mutant G93A SOD1) and UPR activation can be longitudinally monitored in single neurons over the process of neurodegeneration by automated microscopy. Using fluorescent UPR reporters we established the temporal and causal relationship between UPR and neuronal death by Cox regression models. Pharmacological inhibition of discrete UPR processes allowed us to establish the contribution of PERK (PKR-like ER kinase) and IRE1 (inositol-requiring enzyme-1) mechanisms to neuronal fate. Importantly, inhibition of PERK signaling with its downstream inhibitor ISRIB, but not with the direct PERK kinase inhibitor GSK2606414, significantly enhanced the survival of G93A SOD1-expressing neurons. Characterization of the inhibitory properties of both drugs under ER stress revealed that in neurons (but not in glial cells) ISRIB overruled only part of the translational program imposed by PERK, relieving the general inhibition of translation, but maintaining the privileged translation of ATF4 (activating transcription factor 4) messenger RNA. Surprisingly, the fine-tuning of the PERK output in G93A SOD1-expressing neurons led to a reduction of IRE1-dependent signaling. Together, our findings identify ISRIB-mediated translational reprogramming as a new potential ALS therapy.

Alpha-synuclein (aSyn) protein levels are sufficient to drive Parkinson's disease (PD) and other synucleinopathies. Despite the biomedical/therapeutic potential of aSyn protein regulation, little is known about mechanisms that limit/control aSyn levels. Here, we investigate the role of a post-translational modification, N-terminal acetylation, in aSyn neurotoxicity. N-terminal acetylation occurs in all aSyn molecules and has been proposed to determine its lipid binding and aggregation capacities; however, its effect in aSyn stability/neurotoxicity has not been evaluated. We generated N-terminal mutants that alter or block physiological aSyn N-terminal acetylation in wild-type or pathological mutant E46K aSyn versions and confirmed N-terminal acetylation status by mass spectrometry. By optical pulse-labeling in living primary neurons we documented a reduced half-life and accumulation of aSyn N-terminal mutants. To analyze the effect of N-terminal acetylation mutants in neuronal toxicity we took advantage of a neuronal model where aSyn toxicity was scored by longitudinal survival analysis. Salient features of aSyn neurotoxicity were previously investigated with this approach. aSyn-dependent neuronal death was recapitulated either by higher aSyn protein levels in the case of WT aSyn, or by the combined effect of protein levels and enhanced neurotoxicity conveyed by the E46K mutation. aSyn N-terminal mutations decreased E46K aSyn-dependent neuronal death both by reducing protein levels and, importantly, by reducing the intrinsic E46K aSyn toxicity, being the D2P mutant the least toxic. Together, our results illustrate that the N-terminus determines, most likely through its acetylation, aSyn protein levels and toxicity, identifying this modification as a potential therapeutic target.

Background & Aims HDV infection induces the most severe form of human viral hepatitis. However, the specific reasons for the severity of the disease remain unknown. Recently, we developed an HDV replication mouse model in which, for the first time, liver damage was detected. Methods HDV and HBV replication-competent genomes and HDV antigens were delivered to mouse hepatocytes using adeno-associated vectors (AAVs). Aminotransferase elevation, liver histopathology, and hepatocyte death were evaluated and the immune infiltrate was characterized. Liver transcriptomic analysis was performed. Mice deficient for different cellular and molecular components of the immune system, as well as depletion and inhibition studies, were employed to elucidate the causes of HDV-mediated liver damage. Results AAV-mediated HBV/HDV coinfection caused hepatocyte necrosis and apoptosis. Activated T lymphocytes, natural killer cells, and proinflammatory macrophages accounted for the majority of the inflammatory infiltrate. However, depletion studies and the use of different knockout mice indicated that neither T cells, natural killer cells nor macrophages were necessary for HDV-induced liver damage. Transcriptomic analysis revealed a strong activation of type I and II interferon (IFN) and tumor necrosis factor (TNF)-α pathways in HBV/HDV-coinfected mice. While the absence of IFN signaling had no effect, the use of a TNF-α antagonist resulted in a significant reduction of HDV-associated liver injury. Furthermore, hepatic expression of HDAg resulted in the induction of severe liver damage, which was T cell- and TNF-α-independent. Conclusions Both host (TNF-α) and viral (HDV antigens) factors play a relevant role in HDV-induced liver damage. Importantly, pharmacological inhibition of TNF-α may offer an attractive strategy to aid control of HDV-induced acute liver damage. Lay summary Chronic hepatitis delta constitutes the most severe form of viral hepatitis. There is limited data on the mechanism involved in hepatitis delta virus (HDV)-induced liver pathology. Our data indicate that a cytokine (TNF-α) and HDV antigens play a relevant role in HDV-induced liver damage., Graphical abstract, Highlights • There is limited data on the mechanisms involved in HDV-induced liver pathology. • Our data indicate that both TNF-α and HDV antigens play a relevant role in HDV-induced liver damage. • Pharmacological inhibition of TNF-α may offer an attractive strategy to aid control of HDV-induced acute liver damage.

Background Endoplasmic reticulum (ER) stress results from protein misfolding imbalance and has been postulated as a therapeutic strategy. ER stress activates the unfolded protein response which leads to a complex cellular response, including the upregulation of aberrant protein degradation in the ER, with the goal of resolving that stress. O(6)-methylguanine DNA methyltransferase (MGMT), N-methylpurine DNA glycosylase (MPG), and Rad51 are DNA damage repair proteins that mediate resistance to temozolomide in glioblastoma. In this work we sought to evaluate whether ER stress-inducing drugs were able to downmodulate DNA damage repair proteins and become candidates to combine with temozolomide. Methods MTT assays were performed to evaluate the cytotoxicity of the treatments. The expression of proteins was evaluated using western blot and immunofluorescence. In vivo studies were performed using 2 orthotopic glioblastoma models in nude mice to evaluate the efficacy of the treatments. All statistical tests were 2-sided. Results Treatment of glioblastoma cells with ER stress-inducing drugs leads to downregulation of MGMT, MPG, and Rad51. Inhibition of ER stress through pharmacological treatment resulted in rescue of MGMT, MPG, and Rad51 protein levels. Moreover, treatment of glioblastoma cells with salinomycin, an ER stress-inducing drug, and temozolomide resulted in enhanced DNA damage and a synergistic antitumor effect in vitro. Of importance, treatment with salinomycin/temozolomide resulted in a significant antiglioma effect in 2 aggressive orthotopic intracranial brain tumor models. Conclusions These findings provide a strong rationale for combining temozolomide with ER stress-inducing drugs as an alternative therapeutic strategy for glioblastoma.

Early life events are associated with the susceptibility to chronic diseases in adult life. Perturbations of endoplasmic reticulum (ER) homeostasis activate the unfolded protein response (UPR), which contributes to the development of metabolic alterations. Our aim was to evaluate liver UPR in an animal model of intrauterine growth restriction (IUGR). A significantly increased expression of X-box binding protein-1 spliced (XBP1s) mRNA (p

Acute intermittent porphyria (AIP) is a hepatic metabolic disease that results from haplo-insufficient activity of porphobilinogen deaminase (PBGD). The dominant clinical feature is acute intermittent attacks when hepatic heme synthesis is activated by endocrine or exogenous factors. Gene therapy vectors over-expressing PBGD protein in the liver offers potential as a cure for AIP. Here, we developed a helper-dependent adenovirus (HDA) encoding human PBGD (hPBGD) and assessed its therapeutic efficacy in a murine model of AIP. Intravenous or intrahepatic administration of HDA-hPBGD to AIP mice resulted in a sustained hepatic hPBGD expression in a dose-dependent manner. Intrahepatic administration conveyed full protection against induced porphyria attacks at a significantly lower viral dose than intravenous injection. Transgenic hPBGD accumulated only in the cytosol of hepatocytes as the endogenous protein. Characterization of PBGD-deficient mouse strains revealed that a strong PBGD deficiency causes the chronic disturbance of cytosolic and endoplasmic reticulum folding machineries. This disturbance was completely restored over time by the over-expression of hPBGD. HDA-hPBGD is a promising vector that protects against porphyria attacks and resolves the chronic folding stress associated with low levels of PBGD activity.

MAJOR ARTICLE Case-Control Study of Shigellosis in San Francisco: The Role of Sexual Transmission and HIV Infection Toma´s J. Arago´n, 1,2 Duc J. Vugia, 3,4 Sue Shallow, 4 Michael C. Samuel, 4 Arthur Reingold, 2,4 Frederick J. Angulo, 5 and Williamson Z. Bradford 4 San Francisco Department of Public Health, City and County of San Francisco, San Francisco, 2 School of Public Health, University of California at Berkeley, Berkeley, 3 California Department of Health Services, Richmond, and 4 California Emerging Infections Program, Oakland, California; and 5 Centers for Disease Control and Prevention, Atlanta, Georgia (See the editorial commentary by Daskalakis and Blaser on pages 335–7) Background. Shigella species infect ∼450,000 persons annually in the United States. Person-to-person trans- mission of Shigella species, which have a low infectious dose, occurs frequently, particularly in areas with poor sanitation and hygiene. Sexual transmission of Shigella species among men who have sex with men (MSM) has been inferred from outbreaks of shigellosis among that population, and limited studies have suggested the im- portance of human immunodeficiency virus (HIV) infection as a risk factor for shigellosis. No population-based study of sporadic shigellosis has evaluated the role of sexual practices (especially among MSM) and HIV infection along with other established risk factors for shigellosis. Methods. We conducted a population-based case-control study of shigellosis in adults in San Francisco, Cal- ifornia, during the period 1998–1999. Cases of Shigella infection were identified through laboratory-based active surveillance conducted by the California Emerging Infections Program. Seventy-six case patients were matched by sex with 146 control subjects. Exposure data were collected on established risk factors, sexual practices, and HIV infection status. Bivariable and multivariable analyses were conducted. Population-attributable fractions were calculated. Results. From the multivariable analysis, for men, shigellosis was associated with MSM (odds ratio [OR], 8.24; 95% confidence interval [CI], 2.70–25.2), HIV infection (OR, 8.17; 95% CI, 2.71–24.6), direct oral-anal contact (OR, 7.50; 95% CI, 1.74–32.3), and foreign travel (OR, 20.0; 95% CI, 5.26–76.3), with population-attributable fractions of 0.72, 0.42, 0.31, and 0.18, respectively. For women, shigellosis was associated only with foreign travel (OR, 21.0; 95% CI, 2.52–899), with a population-attributable fraction of 0.37. Conclusions. Among MSM, shigellosis is predominantly a sexually transmitted disease, with direct oral-anal contact conferring the highest risk and HIV infection likely contributing to increased host susceptibility. Each year, an estimated 450,000 persons in the United States are infected with Shigella species, resulting in 6200 hospitalizations and 70 deaths [1]. Humans and other primates are the only natural reservoirs for Shi- gella species [2]. Shigella species are transmitted by the fecal-oral route, and most infections are transmitted from person to person, reflecting the low infectious dose [3]; as few as 10 viable organisms can result in clinical infection [4]. In areas in which infection is prev- Received 6 September 2006; accepted 27 September 2006; electronically published 29 December 2006. Reprints or correspondence: Dr. Toma´s J. Arago´n, School of Public Health, Div. of Epidemiology, University of California at Berkeley, 140 Warren Hall, MC-7360, Berkeley, CA 94720-7360 (aragon@berkeley.edu). Clinical Infectious Diseases 2007; 44:327–34 2006 by the Infectious Diseases Society of America. All rights reserved. alent, risk for Shigella infection increases with poor hand hygiene, ingestion of contaminated food or water, inadequate sanitation and toileting, overcrowding, and sexual contact [5–13]. Among reported culture-confirmed infections in the United States during the period 1989–2002, 72% were due to Shigella sonnei, 18% were due to Shigella flexneri, 1.6% were due to Shigella boydii, and 0.7% were due to Shigella dysenteriae [3]. Most reported cases occurred in children ! 10 years of age, followed by women 20– 39 years of age; the high rate of infection in the latter group was presumably related to caring for infected children. In the mid-1970s, shigellosis was recognized as a potentially sexually transmitted disease among men who have sex with men (MSM) [7, 14, 15]. In the late 1970s and early 1980s, the increased incidence of S. flexneri infection in men was attributed to the sexual Sexual Transmission of Shigellosis • CID 2007:44 (1 February) • 327

INFECTIOUS DISEASE/EDITORIAL Tomas J. Aragon, MD, DrPH Susan E. Fernyak, MD, MPH From the Center for Infectious Disease Preparedness, University of California–Berkeley (Aragon), Berkeley, CA; the Department of Medicine, University of California–San Francisco (Aragon, Fernyak), San Francisco, CA; and the San Francisco Department of Public Health (Aragon, Fernyak), City and County of San Francisco, CA. Editor’s note: This article was first published on Annals’ Web site (www.mosby.com/AnnEmergMed) on September 16, 2003. Articles of particular interest are published on the Web site in advance of their appearance in the print journal. In the future, an increasing percentage of our content will be published first on the Web, predat- ing the print publication as a service to our readers. Copyright © 2003 by the American College of Emergency Physicians. doi:10.1067/mem.2003.418 NOVEMBER 2003 ANNALS OF EMERGENCY MEDICINE The Risks and Benefits of Pre-event Smallpox Vaccination: Where You Stand Depends on Where You Sit See related article, p. 665, and editorial, p. 685. [Ann Emerg Med. 2003;42:681-684.] In this issue of Annals, Thorne et al 1 present a compre- hensive review of smallpox vaccination complications, as well as special issues related to smallpox vaccine programs and transmission of vaccinia. This topic is of importance to emergency physicians, who have a spe- cial role in the medical and public health response to microbial threats such as smallpox. In an outbreak, persons with smallpox are likely to seek care at emer- gency care settings even before an outbreak or release has been recognized. Like severe acute respiratory syn- drome, 2 health care workers may be infected with smallpox at higher rates unless they recognize this con- tagious threat and practice good infection control or are immune through prior successful smallpox vacci- nation. To prepare for such a scenario, the federal gov- ernment initiated the Smallpox Vaccination Program and recommended pre-event smallpox vaccination of up to 440,000 civilian public health and hospital-based personnel during the winter and spring of 2003 (Phase 1). 3 This was to be followed by Phase 2, where an addi- tional 10 million public safety and health care workers would be offered vaccine. 3 Despite federal support of this program, 37,802 civilians had been vaccinated as of June 20, 2003, 4 less than 10% of the anticipated number. Clearly, health care workers have voted with their arms on this initia

Dispatches HIV Infection as a Risk Factor for Shigellosis 1 Jefferson T. Baer,* Duc J. Vugia,*†‡ Arthur L. Reingold ,*§ Tomas Aragon,¶ Frederick J. Angulo,# and Williamson Z. Bradford*§** *California Emerging Infections Program, San Francisco, California, USA; †California Department of Health Services, Berkeley, California, USA; ‡University of California, San Francisco, California, USA; §School of Public Health, University of California, Berkeley, California, USA; ¶San Francisco Department of Public Health, San Francisco, California, USA; #Centers for Disease Control and Prevention, Atlanta, Georgia, USA; and **IntraBiotics Pharmaceuticals, Mountain View, California, USA We investigated cases of shigellosis in San Francisco and Alameda Counties identified during 1996 by active laboratory surveillance to assess the role of HIV infection as a risk factor for shigellosis. Dramatically elevated rates of shigellosis in HIV-infected persons implicate HIV infection as an important risk factor for shigellosis in San Francisco. Shigella infections are responsible for an estimated 300,000 illnesses and 600 deaths per year in the United States and more than 600,000 deaths per year worldwide (1). Shigella species are typically transmitted by direct or indirect fecal-oral contact; as a result, shigellosis has long been associated with outbreaks in day-care centers, nursing homes, and institutionalized populations (2-4). However, several studies have demonstrated an increased frequency of shigello- sis cases in young adult men residing in urban settings who have little, if any, exposure to these traditionally recognized risk groups (5-9). These investigations also suggest that Shigella infection occurs during the practice of gay sex; however, since most of these studies occurred before the HIV epidemic, the relationship between HIV infection and gay sex and the subsequent risk for shigellosis has yet to be evaluated (5-9). HIV-infected persons are at increased risk for infection by several common enteric pathogens (10). Previous investigations have demonstrated that HIV-infected patients are at 20 times greater risk for infection with Address for correspondence: Williamson Z. Bradford, IntraBiotics Pharmaceuticals, Inc., 1255 Terra Bella Ave., Mountain View, CA 94080, USA; fax: 650-969-0663; e-mail: BBradford@intrabiotics.com. 1 Presented Salmonella species and 39 times greater risk for infection with Campylobacter species than the general population (11,12). To determine the rate of shigellosis in HIV-infected persons, we investigated all cases of shigellosis in San Francisco, a county with a high prevalence of HIV infection and a high incidence of shigellosis. Alameda, a neighboring county with lower rates of shigellosis and HIV infection, was used as a comparison area for our investigation because of its proximity and differing shigellosis and HIV epidemiology. During 1996, cases of culture-confirmed shigellosis were identified in San Francisco and Alameda Counties by active surveillance in 28 laboratories for isolates of Shigella species cultured from any anatomic site as part of the California Emerging Infections Program. The program comprises one of five sites in the Foodborne Diseases Active Surveillance Net- work (FoodNet), which is part of the Centers for Disease Control and Prevention’s Emerging Infections Program. All available medical records of patients were reviewed by a standardized data collection instrument detailing demographic and medical information. Data concerning sexual activity and orientation and foreign travel were obtained from routine telephone interviews of patients with shigellosis, conducted by the San in part at the International Conference on Emerging Infections, March 1998, Atlanta, Georgia. Emerging Infectious Diseases Vol. 5, No. 6, November–December 1999

et al., [Background & Aims]: Cardiotrophin-1 (CT-1) is a hepatoprotective cytokine that modulates fat and glucose metabolism in muscle and adipose tissue. Here we analyzed the changes in hepatic fat stores induced by recombinant CT-1 (rCT-1) and its therapeutic potential in non-alcoholic fatty liver disease (NAFLD). [Methods]: rCT-1 was administered to two murine NAFLD models: ob/ob and high fat diet-fed mice. Livers were analyzed for lipid composition and expression of genes involved in fat metabolism. We studied the effects of rCT-1 on lipogenesis and fatty acid (FA) oxidation in liver cells and the ability of dominant negative inhibitor of AMP-activated protein kinase (AMPK) to block these effects. [Results]: CT-1 was found to be upregulated in human and murine steatotic livers. In two NAFLD mouse models, treatment with rCT-1 for 10 days induced a marked decrease in liver triglyceride content with augmented proportion of poly-unsaturated FA and reduction of monounsaturated species. These changes were accompanied by attenuation of inflammation and improved insulin signaling. Chronic administration of rCT-1 caused downregulation of lipogenic genes and genes involved in FA import to hepatocytes together with amelioration of ER stress, elevation of NAD+/NADH ratio, phosphorylation of LKB1 and AMPK, increased expression and activity of sirtuin1 (SIRT1) and upregulation of genes mediating FA oxidation. rCT-1 potently inhibited de novo lipogenesis and stimulated FA oxidation in liver cells both in vitro and in vivo. In vitro studies showed that these effects are mediated by activated AMPK. [Conclusions]: rCT-1 resolves hepatic steatosis in obese mice by mechanisms involving AMPK activation. rCT-1 deserves consideration as a potential therapy for NAFLD. © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved., Work in the authors’ laboratory was supported by Fundación para la Investigación Médica Aplicada (FIMA) and by Fondo de Investigaciones Sanitarias (FIS) PI10/01516 to M.B., MICINN SAF300–45 to J.P., (BFU) 2010-18826 to J.B. and by Instituto de Salud Carlos III, CIBERehd. DC and EL have been supported by DIGNA Biotech.

Background In recent years, national and global mortality data have been characterized in terms of well-established risk factors. In this regard, alcohol consumption has been called the third leading "actual cause of death" (modifiable behavioral risk factor) in the United States, after tobacco use and the combination of poor diet and physical inactivity. Globally and in various regions of the world, alcohol use has been established as a leading contributor to the overall burden of disease and as a major determinant of health disparities, but, to our knowledge, no one has characterized alcohol-related harm in such broad terms at the local level. We asked how alcohol-related premature mortality in San Francisco, measured in years of life lost (YLLs), compares with other well-known causes of premature mortality, such as ischemic heart disease or HIV/AIDS. Methods We applied sex- and cause-specific population-attributable fractions (PAFs) of years of life lost (YLLs) from the Global Burden of Disease Study to 17 comparable outcomes among San Francisco males and females during 2004-2007. We did this in three ways: Method 1 assumed that all San Franciscans drink like populations in developed economies. These estimates were limited to alcohol-related harm. Method 2 modified these estimates by including several beneficial effects. Method 3 assumed that Latino and Asian San Franciscans drink alcohol like populations in the global regions related to their ethnicity. Results By any of these three methods, alcohol-related premature mortality accounts for roughly a tenth of all YLLs among males. Alcohol-related YLLs among males are comparable to YLLs for leading causes such as ischemic heart disease and HIV/AIDS, in some instances exceeding them. Latino and black males bear a disproportionate burden of harm. Among females, for whom estimates differed more by method and were smaller than those for males, alcohol-related YLLs are comparable to leading causes which rank somewhere between fifth and fourteenth. Conclusions Alcohol consumption is a major contributor to premature mortality in San Francisco, especially among males. Interventions to avert alcohol-related harm in San Francisco should be taken at the population level and deserve the same attention that is given to other major risk factors, such as smoking or obesity.

Background Previous smallpox ring vaccination models based on contact tracing over a network suggest that ring vaccination would be effective, but have not explicitly included response logistics and limited numbers of vaccinators. Methods We developed a continuous-time stochastic simulation of smallpox transmission, including network structure, post-exposure vaccination, vaccination of contacts of contacts, limited response capacity, heterogeneity in symptoms and infectiousness, vaccination prior to the discontinuation of routine vaccination, more rapid diagnosis due to public awareness, surveillance of asymptomatic contacts, and isolation of cases. Results We found that even in cases of very rapidly spreading smallpox, ring vaccination (when coupled with surveillance) is sufficient in most cases to eliminate smallpox quickly, assuming that 95% of household contacts are traced, 80% of workplace or social contacts are traced, and no casual contacts are traced, and that in most cases the ability to trace 1–5 individuals per day per index case is sufficient. If smallpox is assumed to be transmitted very quickly to contacts, it may at times escape containment by ring vaccination, but could be controlled in these circumstances by mass vaccination. Conclusions Small introductions of smallpox are likely to be easily contained by ring vaccination, provided contact tracing is feasible. Uncertainties in the nature of bioterrorist smallpox (infectiousness, vaccine efficacy) support continued planning for ring vaccination as well as mass vaccination. If initiated, ring vaccination should be conducted without delays in vaccination, should include contacts of contacts (whenever there is sufficient capacity) and should be accompanied by increased public awareness and surveillance.

Background The United States (US) has re-instituted smallpox vaccinations to prepare for an intentional release of the smallpox virus into the civilian population. In an outbreak, people of all ages will be vaccinated. To prepare for the impact of large-scale ring and mass vaccinations, we conducted a systematic review of the complication and mortality risks of smallpox vaccination. We summarized these risks for post-vaccinial encephalitis, vaccinia necrosum (progressive vaccinia), eczema vaccinatum, generalized vaccinia, and accidental infection (inadvertant autoinoculation). Methods Using a MEDLINE search strategy, we identified 348 articles, of which seven studies met our inclusion criteria (the number of primary vaccinations and re-vaccinations were reported, sufficient data were provided to calculate complication or case-fatality risks, and comparable case definitions were used). For each complication, we estimated of the complication, death, and case-fatality risks. Results The life-threatening complications of post-vaccinial encephalitis and vaccinia necrosum were at least 3 and 1 per million primary vaccinations, respectively. Twenty-nine percent of vaccinees with post-vaccinial encephalitis died and 15% with vaccinia necrosum died. There were no deaths among vaccinees that developed eczema vaccinatum; however, 2.3% of non-vaccinated contacts with eczema vaccinatum died. Among re-vaccinees, the risk of post-vaccinial encephalitis was reduced 26-fold, the risk of generalized vaccinia was reduced 29-fold, and the risk of eczema vaccinatum was reduced 12-fold. However, the risk reductions of accidental infection and vaccinia necrosum were modest (3.8 and 1.5 fold respectively).

Background In persons with acquired immunodeficiency syndrome (AIDS), Cryptosporidium parvum causes a prolonged, severe diarrheal illness to which there is no effective treatment, and the risk of developing cryptosporidiosis from drinking tap water in non-outbreak settings remains uncertain. To test the hypothesis that drinking tap water was associated with developing cryptosporidiosis, we conducted a matched case-control study among persons with AIDS in San Francisco. Methods Among patients reported to the San Francisco AIDS Registry from May 1996 through September 1998, we compared patients who developed cryptosporidiosis to those who did not. Cases were individually matched to controls based on age, sex, race/ethnicity, CD4+ T lymphocyte count, date of CD4+ count, and date of case diagnosis. Population attributable fractions (PAFs) were calculated. Results The study consisted of 49 cases and 99 matched controls. In the multivariable analysis with adjustments for confounders, tap water consumption inside and outside the home at the highest exposure categories was associated with the occurrence of cryptosporidiosis (inside the home: odds ratio (OR), 6.76; 95% CI 1.37–33.5, and outside the home: OR 3.16; 95% CI 1.23–8.13). The PAF was 85%; that is, the proportion of cases of cryptosporidiosis in San Francisco AIDS patients attributable to tap water consumption could have been as high as 85%. Conclusions Although the results from this observational study cannot be considered definitive, until there is more data, we recommend persons with AIDS, especially those with compromised immune systems, consider avoiding tap water.

OBJECTIVES: This study determined infection risk for HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) from needle reuse at a phlebotomy center that possibly exposed 3810 patients to infection. METHODS: We used a model for the risk of infection per blood draw, supplemented by subsequent testing results from 1699 patients. RESULTS: The highest risk of transmission was for HBV infection: 1.1 x 10(-6) in the best case and 1.2 x 10(-3) in the (unlikely) worst case. Subsequent testing yielded prevalence rates of 0.12%, 0.41%, and 0.88% for HIV, HBV, and HCV, respectively, lower than National Health and Nutrition Examination Survey III prevalence estimates. CONCLUSIONS: The infection risk was very low; few, if any, transmissions are likely to have occurred.

The authors reviewed the medical records of 194 human immunodeficiency virus (HIV)-positive patients newly diagnosed with cryptosporidiosis and all 3,564 patients with newly diagnosed acquired immunodeficiency syndrome (AIDS) at San Francisco General Hospital for the period 1986-1992. The study was designed to address three questions: 1) How do AIDS patients who present with cryptosporidiosis differ from other patients with AIDS? 2) What factors are associated with survival among AIDS patients with newly diagnosed cryptosporidiosis? 3) Does a diagnosis of cryptosporidiosis impact survival after AIDS diagnosis? A total of 194 cases of cryptosporidiosis among HIV-infected patients were identified during the study period. Of the 194 patients, 109 (56%) had no prior diagnosis of AIDS. These 109 patients represented 3.1% of the 3,564 newly diagnosed cases of AIDS in the same period. Among the 134 patients with CD4 T-lymphocyte counts performed within 3 months of Cryptosporidium diagnosis, 34 (25%) had CD4 counts greater than 209 cells/ml. In a multivariate conditional logistic regression model, the incidence of Cryptosporidium was related to ethnicity (for blacks vs. whites, matched odds ratio (OR) = 0.15, 95% confidence interval (CI) 0.03-0.73), CD4 count (for a CD4 count ofor = 53 cells/ml vs.53 cells/ml, matched OR = 12.60, 95% CI 4.01-39.61), and age (for a 10-year increase, matched OR = 0.51, 95% CI 0.27-0.98). Two factors measured at the time of Cryptosporidium diagnosis were identified as being independently associated with survival (p0.001) in the proportional hazards model: CD4 countor = 53 cells/ml versus53 cells/ml (relative hazard = 6.18, 95% CI 2.99-12.76) and hematocritor 37% versus37% (relative hazard = 2.27, 95% CI 1.22-4.22). The median durations of survival in the four subgroups of Cryptosporidium-infected patients defined by these two variables differed significantly from each other (range, 204-1,119 days). Cryptosporidiosis as an initial AIDS-defining diagnosis was associated with an elevated relative hazard of death in comparison with other AIDS-defining diagnoses (relative hazard = 2.01, 95% CI 1.38-2.93). These data identify the groups of HIV-infected individuals at risk for presentation with symptomatic Cryptosporidium infection; the distinct survival patterns among subgroups of those patients already infected with this parasite; and the survival of AIDS patients with newly diagnosed cryptosporidiosis relative to patients with other AIDS-defining conditions. Such information is necessary for the design of prospective studies, the development of prophylactic strategies, the evaluation of candidate therapies, and the provision of prognostic information to patients.

We conducted a retrospective cohort study to evaluate the occurrence of bacteremia and associated mortality among hospitalized patients who were seropositive for the human immunodeficiency virus (HIV) and who developed fever and neutropenia following antineoplastic chemotherapy or for other reasons. Review of medical records revealed 224 episodes in 142 patients. Of these episodes, 57% occurred following antineoplastic chemotherapy, and 43% occurred under other circumstances. Members of the chemotherapy group had significantly less-advanced HIV disease, a lower mean absolute-neutrophil-count nadir, and a shorter duration of hospitalization. There was no difference between the two groups in the frequency of bacteremia or mortality due to all causes when they were compared by multivariate analysis. Statistically significant univariate and multivariate predictors of bacteremia included sepsis syndrome and concurrent infection. Predictors of mortality included sepsis syndrome, concurrent infection, bacteremia, and antimicrobial therapy. This study suggests that the cause of neutropenia in HIV-seropositive patients is not a predictor of the outcome of fever and neutropenic episodes. Instead, clinical presentation and concomitant illnesses have a greater impact on outcome for a patient.