A health disparities perspective on developing emerging infectious disease preparedness

A systematic review of the literature yielded 10 articles that explored the interaction between race/ethnicity, citizenship, socioeconomic status, and health literacy domains with respect to preparedness agenda development. Current emerging infectious disease (EID) preparedness plans do not adequately address the needs of vulnerable populations for the events before, during, and after an epidemic. Central to the disadvantage of most vulnerable populations are various health disparity domains that persist as barriers for individuals and communities alike to engage in preparedness efforts. Seven out of the ten articles discussed the importance of including health disparity domains in preparedness policy. Two proposed frameworks for an emerging infectious disease framework that considers health disparities are presented in this study. ^ Framework 1 is beneficial for the evaluation phase after a disaster has struck and preparedness efforts have been initiated. It considers several existing disparities and remediation strategies at the individual, community, and system levels to reach adequate restructuring of preparedness aims. Framework 2 serves as a "how to" carry out preparedness during a disaster event. It is a revision of a framework proposed by Blumenshine et al. (2008) and explores those characteristics central to pandemic preparedness plan development/deployment. Although two frameworks were devised, no one framework will adequately address the needs of vulnerable populations during an epidemic. However, the two frameworks propose to demonstrate the inclusion of important health disparity domains in preparedness plan development. ^ The National Consensus Panel for Emergency Preparedness and Cultural Diversity has released guidelines that are considered the leading strategies necessary to reorient preparedness infrastructure. In order for vulnerable populations to benefit from ample protection during a disaster, inclusion of health disparity domains in the development phases of preparedness must occur prior to full deployment in communities. Although "promising practices" and other methods at the frontier of exploring these multidimensional constraints has entered the research arena, new studies on adequate preparedness merit further investigation and support.^

Impacto clínico de la pancitopenia en pacientes hospitalizados

Objetivo: Determinar etiología, manifestaciones clínicas, morbimortalidad y recursos diagnósticos y terapéuticos utilizados en pacientes internados con pancitopenia. Material y métodos: Estudio protocolizado, descriptivo y observacional de 14 meses. Criterios de inclusión: pacientes internados con pancitopenia definida por hemoglobina (Hb) <12 g/dL; plaquetas <150.000/ mL y leucocitos <3.800/mL. Los datos fueron analizados con Epi Info 6.04. Resultados: Se diagnosticaron 54 casos de pancitopenia. Prevalencia: 22/1.000 egresos. Edad media: 48,72 años (DS±20,64); 29,63% fueron > 65 años y 53,70% hombres. Permanencia media: 17,13 días (DS±13,22) vs 7,25 días (DS±5,4) del Servicio (p<0.0001). Charlson medio: 7,16 (DS±2,96) y APACHEII medio: 12 (DS±5,04). El 83,33% (45/54, IC95%70,71-92,08) de las pancitopenias fueron secundarias a compromiso medular, 22 casos (40,74%; IC95%27,57-54,97) postquimioterapia (15 en neoplasias oncohematológicas y 7 en sólidas), 11 (20,37%; IC95%10,63-33,53) por mieloptisis y 4 casos (7,41%; IC95%2,06-17,89) por megaloblastosis. El 16,66% (9/54; IC95%7,92- 29,29) fue secundaria a hiperesplenismo y el 16,66% asociadas a infecciones (3 casos por SIDA). Se realizó estudio de médula ósea en 19 casos (35,18%). El 96,29% (IC95%87,25-99,55) presentó comórbidas. El síndrome de respuesta inflamatoria sistémica (85,19%), síndrome anémico (77,8%) y púrpura (50%) fueron las manifestaciones clínicas más frecuentes. Presentó sepsis el 81,48% (IC95%68,57-90,75) y el 29,63% (IC95%17,98-46,31) hemorragias. El 81,48% tuvo infecciones; el 50% de origen nosocomial y el 65,91% clínicamente documentadas. El 34,09% (IC95%20,49-49,92) tuvo aislamiento microbiológico, con hemocultivos positivos en 29,55%. El 51,85% (IC95%37,84-65,66) desarrolló neutropenia febril (75% postquimioterapia). El 64,81% recibió hemoderivados y factores estimulantes de colonias (G-CSF) el 46,34% (IC95%32,62-60,39). La mortalidad fue mayor a la media global del Servicio (16,66 vs 8,65%)(p=0.07).- Conclusiones: Las pancitopenias en pacientes hospitalizados se caracterizaron por ser secundarias a compromiso medular, hiperesplenismo e infecciones, asociarse a permanencia prolongada, altos índices de comorbilidad, complicaciones infecciosas, y mayor mortalidad que la media global del Servicio.

Endocarditis infecciosa : significado de la disfunción renal

Objetivo: Determinar la significación clínica y pronóstica de la disfunción renal en pacientes con Endocarditis Infecciosa (EI) Material y método: Estudio protocolizado, descriptivo, observacional y transversal de pacientes con EI diagnosticados según criterios de Duke. Se realizó un análisis comparativo entre los pacientes con EI sin (Grupo Sin) y con Disfunción Renal (Grupo DR), que se definió en base a uremia > 0.60 g/l y/o creatininemia > 1.5 mg/dl y/o hematuria o proteinuria. Fueron analizados en EPI info 6.04. Resultados: De un total de 110 EI incluidas, 58 (52.7%) presentaron DR principalmente secundaria a glomerulonefritis (n 22), sepsis (n 14), insuficiencia renal crónica (n 5), insuficiencia cardíaca, nefropatía diabética y nefrotoxicidad (n 4 cada una) y embólica (n 1). No hubo diferencias en la permanencia media hospitalaria (32 DS±23.3 vs 26.32 DS±17.28 días), el sexo (masculino: 60.3 vs 71.25%) y la demora diagnóstica (5.5 (DS±7.23) vs. 5.4 (DS±7.64 días)(pNS). La edad media fue mayor en el grupo DR en el LS (49.62 DS±15.71 vs 43.53 DS±17.94 años). El Grupo DR tuvo mas frecuentemente EI Definida (87.9 vs 67.3%) (p=0.0089) y no hubo diferencias en la localización Mitral (48.3 vs 48.1%) y Aórtica (44.8 vs 34.6%). La valvulopatía degenerativa se presentó en el LS en DR (34.5 VS 19.6%)(p=0.07). No hubo diferencias en la presencia de comórbidas (62.1 vs 71.2%) (pNS) pero la enfermedad últimamente fatal ocurrió mas frecuentemente en DR (51.4 vs 21.6%)(p=0.05). Al ingreso sólo la presencia de rales pulmonares (53.4 vs 32.7%) y púrpura cutánea (27.6 vs 13.5%) fueron más frecuentes en DR (p=0.05). La sepsis no controlada (34.5 vs 15.7%), insuficiencia cardíaca (51.7 vs 32.7%), encefalopatía (50 vs 27.5%), shock séptico (24.1 vs 7.8%) y fallo multiorgánico (34.5 vs 3.9%) fueron complicaciones más frecuentes en DR (p<0.05). La fiebre persistente se encontró en el LS en el grupo de DR (48.3 vs 32.7%)(p=0.09). No hubo diferencias en el hallazgo de vegetaciones por ecocardiografía (83.3 vs 75.6%). La anemia (Hb<9 mg/dl) (31.86 DS±53.41 vs 35.21 DS±7.85)(p=0.009), hipergammaglobulinemia (58.5 vs 29.8)(p=0.006) e hiperglucemia (36.1 vs 18.5)(p=0.03) se asociaron a DR. En el grupo con DR fue mas común la EI con cultivos negativos (31.5 vs 0%)(p=0.001) y el predominio de las infecciones por S. aureus Meticilino Resistente (MRSA)(21.6 vs 2.7%) (p=0.02). No hubo diferencias en la indicación de cirugía (31 vs 36.5%). La mortalidad hospitalaria fue significativamente mayor en DR (51.7 vs 25%)(p=0.0041)(OR 3.2, IC95%1.42-7.24). Conclusión: En los pacientes con EI la disfunción renal resultó ser un indicador de desarrollo de complicaciones infecciosas y cardíacas, de infección por MRSA y de mortalidad cruda hospitalaria.-

Bacteriemias por Pseudomonas Aeruginosa : análisis comparativo

Objetivos: Analizar características clínicas y morbimortalidad de las bacteriemias por Pseudomonas aeruginosa comparadas con Klebsiella spp en pacientes hospitalizados en un Servicio de Clínica Médica de adultos. Material y métodos: Estudio protocolizado, descriptivo, observacional de 15 años de duración. Criterio de inclusión: 2 o más hemocultivos positivos para el germen. Los datos fueron procesados en EPI Info 6.04. El criterio de significación se estableció para un error alfa menor del 5%. Resultados: Se detectaron en el período de estudio 282 bacteriemias por bacilos gram negativos de las cuales 19 fueron por Pseudomonas aeruginosa (6.7%) y 76 por Klebsiella (26.9%). No se encontraron diferencias significativas entre ambas en cuanto a edad media [53.9 años (DS±17.9 ) vs 58.7 años (DS±15.2)], sexo (femenino: 26.3 vs 38.2%) ni complicaciones (77.8 vs 77.3%). La presencia de neutropenia (52.6 vs 9.2%)(p<0.0001), comorbilidad mayor (94.7 vs 68.4%)(p<0.05), neoplasias (47.4 vs 22.4%)(p<0.05), uso de corticoides (21.1 vs 3.9%)(p<0.05), e inmunosupresores (31.6 vs 7.9%)(p<0.01), trombocitopenia (77.7 vs 49.3%) (p<0.05) y leucopenia (52.6 vs 21.3%)(p<0.01) fueron más frecuentes en las bacteriemias por P. aeruginosa. Resultó más frecuente la hipoalbuminemia (88.5 vs 37.5%)(p<0.001) en las bacteriemias por Klebsiella spp. No se encontraron diferencias significativas en cuanto a puerta de entrada conocida (78.9 vs 77.6%), anemia (84.2 vs 71.2%), complicaciones infecciosas (84.2 vs 73.7%), descompensación de comórbidas (55.6 vs 51.3%) y encefalopatía (36.8 vs 57.9%)(pNS). La mortalidad precoz (dentro de los 7 días) fue significativamente mayor en el grupo de las bacteriemias por P.aeruginosa (57.1 vs 12%) (p<0.01), sin diferencias en la mortalidad global (36.8 vs 32.9%) (pNS). Conclusiones: Las bacteriemias por P.aeruginosa comparadas con las producidas por Klebsiella spp. se asociaron significativamente a mayor frecuencia de neoplasias, leucopenia, trombocitopenia y neutropenia, comorbilidad mayor, uso de corticoides e inmunosupresores, y a mortalidad precoz.

An ecological approach to anomaly detection: the EIA Model.

The presented work proposes a new approach for anomaly detection. This approach is based on changes in a population of evolving agents under stress. If conditions are appropriate, changes in the population (modeled by the bioindicators) are representative of the alterations to the environment. This approach, based on an ecological view, improves functionally traditional approaches to the detection of anomalies. To verify this assertion, experiments based on Network Intrussion Detection Systems are presented. The results are compared with the behaviour of other bioinspired approaches and machine learning techniques.

Transcripts from a single full-length cDNA clone of hepatitis C virus are infectious when directly transfected into the liver of a chimpanzee

We have succeeded in constructing a stable full-length cDNA clone of strain H77 (genotype 1a) of hepatitis C virus (HCV). We devised a cassette vector with fixed 5′ and 3′ termini and constructed multiple full-length cDNA clones of H77 in a single step by cloning of the entire ORF, which was amplified by long reverse transcriptase–PCR, directly into this vector. The infectivity of two complete full-length cDNA clones was tested by the direct intrahepatic injection of a chimpanzee with RNA transcripts. However, we found no evidence for HCV replication. Sequence analysis of these and 16 additional full-length clones revealed that seven clones were defective for polyprotein synthesis, and the remaining nine clones had 6–28 amino acid mutations in the predicted polyprotein compared with the consensus sequence of H77. Next, we constructed a consensus chimera from four of the full-length cDNA clones with just two ligation steps. Injection of RNA transcripts from this consensus clone into the liver of a chimpanzee resulted in viral replication. The sequence of the virus recovered from the chimpanzee was identical to that of the injected RNA transcripts. This stable infectious molecular clone should be an important tool for developing a better understanding of the molecular biology and pathogenesis of HCV.

Solution structure of a 142-residue recombinant prion protein corresponding to the infectious fragment of the scrapie isoform

The scrapie prion protein (PrPSc) is the major, and possibly the only, component of the infectious prion; it is generated from the cellular isoform (PrPC) by a conformational change. N-terminal truncation of PrPSc by limited proteolysis produces a protein of ≈142 residues designated PrP 27–30, which retains infectivity. A recombinant protein (rPrP) corresponding to Syrian hamster PrP 27–30 was expressed in Escherichia coli and purified. After refolding rPrP into an α-helical form resembling PrPC, the structure was solved by multidimensional heteronuclear NMR, revealing many structural features of rPrP that were not found in two shorter PrP fragments studied previously. Extensive side-chain interactions for residues 113–125 characterize a hydrophobic cluster, which packs against an irregular β-sheet, whereas residues 90–112 exhibit little defined structure. Although identifiable secondary structure is largely lacking in the N terminus of rPrP, paradoxically this N terminus increases the amount of secondary structure in the remainder of rPrP. The surface of a long helix (residues 200–227) and a structured loop (residues 165–171) form a discontinuous epitope for binding of a protein that facilitates PrPSc formation. Polymorphic residues within this epitope seem to modulate susceptibility of sheep and humans to prion disease. Conformational heterogeneity of rPrP at the N terminus may be key to the transformation of PrPC into PrPSc, whereas the discontinuous epitope near the C terminus controls this transition.

Noninfectious virus-like particles produced by Moloney murine leukemia virus-based retrovirus packaging cells deficient in viral envelope become infectious in the presence of lipofection reagents

Retrovirus packaging cell lines expressing the Moloney murine leukemia virus gag and pol genes but lacking virus envelope genes produce virus-like particles constitutively, whether or not they express a transcript from an integrated retroviral provirus. In the absence of a proviral transcript, the assembled particles contain processed gag and reverse transcriptase, and particles made by cells expressing an integrated lacZ provirus also contain viral RNA. The virus-like particles from both cell types are enveloped and are secreted/budded into the extracellular space but are noninfectious. Their physicochemical properties are similar to those of mature retroviral particles. The noninfectious gag pol RNA particles can readily be made infectious by the addition of lipofection reagents to produce preparations with titers of up to 105 colony-forming units per ml.

The Fanconi anemia pathway requires FAA phosphorylation and FAA/FAC nuclear accumulation

Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A–H). Two FA genes, corresponding to complementation groups A and C, have been cloned, but the function of the FAA and FAC proteins remains unknown. We have recently shown that the FAA and FAC proteins bind and form a nuclear complex. In the current study, we analyzed the FAA and FAC proteins in normal lymphoblasts and lymphoblasts from multiple FA complementation groups. In contrast to normal controls, FA cells derived from groups A, B, C, E, F, G, and H were defective in the formation of the FAA/FAC protein complex, the phosphorylation of the FAA protein, and the accumulation of the FAA/FAC protein complex in the nucleus. These biochemical events seem to define a signaling pathway required for the maintenance of genomic stability and normal hematopoiesis. Our results support the idea that multiple gene products cooperate in the FA Pathway.

Sequence variation in the Fanconi anemia gene FAA

Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive syndrome associated with chromosomal instability, hypersensitivity to DNA crosslinking agents, and predisposition to malignancy. The gene for FA complementation group A (FAA) recently has been cloned. The cDNA is predicted to encode a polypeptide of 1,455 amino acids, with no homologies to any known protein that might suggest a function for FAA. We have used single-strand conformational polymorphism analysis to screen genomic DNA from a panel of 97 racially and ethnically diverse FA patients from the International Fanconi Anemia Registry for mutations in the FAA gene. A total of 85 variant bands were detected. Forty-five of the variants are probably benign polymorphisms, of which nine are common and can be used for various applications, including mapping studies for other genes in this region of chromosome 16q. Amplification refractory mutation system assays were developed to simplify their detection. Forty variants are likely to be pathogenic mutations. Seventeen of these are microdeletions/microinsertions associated with short direct repeats or homonucleotide tracts, a type of mutation thought to be generated by a mechanism of slipped-strand mispairing during DNA replication. A screening of 350 FA probands from the International Fanconi Anemia Registry for two of these deletions (1115–1118del and 3788–3790del) revealed that they are carried on about 2% and 5% of the FA alleles, respectively. 3788–3790del appears in a variety of ethnic groups and is found on at least two different haplotypes. We suggest that FAA is hypermutable, and that slipped-strand mispairing, a mutational mechanism recognized as important for the generation of germ-line and somatic mutations in a variety of cancer-related genes, including p53, APC, RB1, WT1, and BRCA1, may be a major mechanism for FAA mutagenesis.

Transgenic knockout mice exclusively expressing human hemoglobin S after transfer of a 240-kb βs-globin yeast artificial chromosome: A mouse model of sickle cell anemia

Sickle cell anemia (SCA) and thalassemia are among the most common genetic diseases worldwide. Current approaches to the development of murine models of SCA involve the elimination of functional murine α- and β-globin genes and substitution with human α and βs transgenes. Recently, two groups have produced mice that exclusively express human HbS. The transgenic lines used in these studies were produced by coinjection of human α-, γ-, and β-globin constructs. Thus, all of the transgenes are integrated at a single chromosomal site. Studies in transgenic mice have demonstrated that the normal gene order and spatial organization of the members of the human β-globin gene family are required for appropriate developmental and stage-restricted expression of the genes. As the cis-acting sequences that participate in activation and silencing of the γ- and β-globin genes are not fully defined, murine models that preserve the normal structure of the locus are likely to have significant advantages for validating future therapies for SCA. To produce a model of SCA that recapitulates not only the phenotype, but also the genotype of patients with SCA, we have generated mice that exclusively express HbS after transfer of a 240-kb βs yeast artificial chromosome. These mice have hemolytic anemia, 10% irreversibly sickled cells in their peripheral blood, reticulocytosis, and other phenotypic features of SCA.

Cloning and mutagenesis of a herpesvirus genome as an infectious bacterial artificial chromosome

A strategy for cloning and mutagenesis of an infectious herpesvirus genome is described. The mouse cytomegalovirus genome was cloned and maintained as a 230 kb bacterial artificial chromosome (BAC) in E. coli. Transfection of the BAC plasmid into eukaryotic cells led to a productive virus infection. The feasibility to introduce targeted mutations into the BAC cloned virus genome was shown by mutation of the immediate-early 1 gene and generation of a mutant virus. Thus, the complete construction of a mutant herpesvirus genome can now be carried out in a controlled manner prior to the reconstitution of infectious progeny. The described approach should be generally applicable to the mutagenesis of genomes of other large DNA viruses.

Density-dependent decline of host abundance resulting from a new infectious disease

Although many new diseases have emerged within the past 2 decades [Cohen, M. L. (1998) Brit. Med. Bull. 54, 523–532], attributing low numbers of animal hosts to the existence of even a new pathogen is problematic. This is because very rarely does one have data on host abundance before and after the epizootic as well as detailed descriptions of pathogen prevalence [Dobson, A. P. & Hudson, P. J. (1985) in Ecology of Infectious Diseases in Natural Populations, eds. Grenfell, B. T. & Dobson, A. P. (Cambridge Univ. Press, Cambridge, U.K.), pp. 52–89]. Month by month we tracked the spread of the epizootic of an apparently novel strain of a widespread poultry pathogen, Mycoplasma gallisepticum, through a previously unknown host, the house finch, whose abundance has been monitored over past decades. Here we are able to demonstrate a causal relationship between high disease prevalence and declining house finch abundance throughout the eastern half of North America because the epizootic reached different parts of the house finch range at different times. Three years after the epizootic arrived, house finch abundance stabilized at similar levels, although house finch abundance had been high and stable in some areas but low and rapidly increasing in others. This result, not previously documented in wild populations, is as expected from theory if transmission of the disease was density dependent.

Engineering the largest RNA virus genome as an infectious bacterial artificial chromosome

The construction of cDNA clones encoding large-size RNA molecules of biological interest, like coronavirus genomes, which are among the largest mature RNA molecules known to biology, has been hampered by the instability of those cDNAs in bacteria. Herein, we show that the application of two strategies, cloning of the cDNAs into a bacterial artificial chromosome and nuclear expression of RNAs that are typically produced within the cytoplasm, is useful for the engineering of large RNA molecules. A cDNA encoding an infectious coronavirus RNA genome has been cloned as a bacterial artificial chromosome. The rescued coronavirus conserved all of the genetic markers introduced throughout the sequence and showed a standard mRNA pattern and the antigenic characteristics expected for the synthetic virus. The cDNA was transcribed within the nucleus, and the RNA translocated to the cytoplasm. Interestingly, the recovered virus had essentially the same sequence as the original one, and no splicing was observed. The cDNA was derived from an attenuated isolate that replicates exclusively in the respiratory tract of swine. During the engineering of the infectious cDNA, the spike gene of the virus was replaced by the spike gene of an enteric isolate. The synthetic virus replicated abundantly in the enteric tract and was fully virulent, demonstrating that the tropism and virulence of the recovered coronavirus can be modified. This demonstration opens up the possibility of employing this infectious cDNA as a vector for vaccine development in human, porcine, canine, and feline species susceptible to group 1 coronaviruses.