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D Scott Schmid

Publications and source records attributed to D Scott Schmid.

12 recordsLinked to original sources
PubMed2004

High rate of varicella complications among Mexican-born adults in Alabama.

OBJECTIVE: Our study examines risk factors for severe varicella in an outbreak among Mexican-born adults, and it compares susceptibility to infection and reliability of self-reported varicella history for these individuals with that for adults born in the United States in the outbreak locale, which may guide vaccination strategies. METHODS: We interviewed case patients and non-case persons in the affected apartment complex and workplace, assessed disease history and susceptibility by testing for varicella-zoster virus immunoglobulin G antibodies, and reviewed the clinical data of case patients. RESULTS: Five of 18 case patients had serious complications for which they sought medical care; 1 was hospitalized for pneumonia, and 1 was hospitalized for Guillain-Barré syndrome. Only intense exposure (e.g., sharing a bed) was marginally associated with severe disease (P=.08). In the workplace, varicella susceptibility was higher among Mexican-born workers (20%) than among workers born in the United States (3%) (adjusted prevalence odds ratio, 5.4; 95% confidence interval, 2.3-14.8). Mexican-born persons had the highest positive predictive value of self-reported disease (100%) in predicting immunity, and those born in the United States had the lowest negative predictive value of self-reported history (10%) in predicting susceptibility. CONCLUSIONS: Varicella is a more serious disease among adults than among children, and Mexican-born adults living in the United States might have a higher risk of acquiring varicella than US-born adults. Varicella outbreaks involving adults should be prioritized for control efforts. Outbreaks can be prevented by vaccinating susceptible adults.

Adolescent↗
PubMed2004

Human monkeypox infection: a family cluster in the midwestern United States.

BACKGROUND: The outbreak of monkeypox in the Midwestern United States during June 2003 marks the first documented human infection in the Western Hemisphere. Consistent with those in outbreaks in Africa, most cases in this outbreak were associated with febrile rash illness. We describe a cluster of monkeypox in a family with a spectrum of clinical illness, including encephalitis, and outline the laboratory confirmation of monkeypox. METHODS: Standardized patient information was collected by questionnaire and medical chart review; all cases described were laboratory confirmed. Laboratory methods included nucleic acid detection, viral culture, serologic testing, histopathologic evaluation, and immunohistochemical testing. RESULTS: Of 3 family members with monkeypox, 2 had rash illness only, and 1 required hospitalization for severe encephalitis. The family member with the mildest clinical course had previously received smallpox vaccination. Diagnostic testing by both polymerase chain reaction and culture revealed infectious monkeypox virus in skin lesions of all 3 patients; 2 patients had orthopoxvirus detected by immunohistochemistry in skin lesions. The patient with encephalitis had orthopoxvirus-reactive immunoglobulin M (IgM) in cerebrospinal fluid. All patients had detectable IgM responses to orthopoxvirus antigens. CONCLUSIONS: These 3 patients illustrate a spectrum of clinical illness with monkeypox despite a common source of exposure; manifestation and severity of illness may be affected by age and prior smallpox vaccination. We report that monkeypox, in addition to causing febrile rash illness, causes severe neurologic infection, and we discuss the use of novel laboratory tests for its diagnosis.

Adult↗
PubMed2004

Incidence of herpes simplex virus type 2 infection in 5 sexually transmitted disease (STD) clinics and the effect of HIV/STD risk-reduction counseling.

The seroincidence of herpes simplex virus type 2 (HSV-2) infection was determined among 1766 patients attending sexually transmitted disease (STD) clinics and enrolled in a randomized, controlled trial of human immunodeficiency virus (HIV)/STD risk-reduction counseling (RRC). Arm 1 received enhanced RRC (4 sessions); arm 2, brief RRC (2 sessions); and arm 3, the control arm, brief informational messages. The overall incidence rate was 11.7 cases/100 person-years (py). Independent predictors of incidence of HSV-2 infection included female sex; black race; residence in Newark, New Jersey; <50% condom use with an occasional partner; and, in females, incident trichomoniasis and bacterial vaginosis. Only 10.8% of new HSV-2 infections were diagnosed clinically. Incidence rates were 12.9 cases/100 py in the control arm, 11.8 cases/100 py in arm 2, and 10.3 cases/100 py in arm 1 (hazard ratio, 0.8 [95% confidence interval, 0.6-1.1], vs. controls). The possible benefit of RRC in preventing acquisition of HSV-2 infection offers encouragement that interventions more specifically tailored to genital herpes may be useful and should be an important focus of future studies.

Adolescent↗
PubMed2004

Genetic profile of an Oka varicella vaccine virus variant isolated from an infant with zoster.

Varicella virus vaccine strain Oka (V-Oka) has in rare cases caused zoster in vaccinated people. Despite broad usage of V-Oka, little is known about varicella-zoster virus genomic sequence variation of strains in vaccine and isolates from patients with vaccine adverse events. Direct sequencing of 20 regions of V-Oka-GSK was compared to the sequences of the original V-Oka-Biken, GlaxoSmithKline Oka vaccine (V-Oka-GSK), and Oka-parental (P-Oka) strains. We analyzed single nucleotide polymorphisms (SNP) differentiating the Oka parental and Oka vaccine strains identified in open reading frames (ORFs) 6, 9A, 10, 21, 31, 39, 50, 51, 52, 54, 55, and 59 and eight base substitutions within ORF 62. Sixteen of these SNP impose an amino acid change in the corresponding gene product. The genotypic analysis revealed that (i) both V-Oka-GSK and V-Oka-Biken comprise mixtures of strains represented in variable proportion from lot to lot; (ii) V-Oka-GSK/zoster isolated from the zoster patient had six wild-type SNP in ORF 9A, 10, 21, 52, 55, and 62 (mutation 108838); (iii) none of the six revertant SNP would reliably discriminate Oka vaccine from the wild type; and (iv) the genomic variation found in V-Oka/zoster might be associated with changes in the biological behavior of the virus. Further studies will be needed to identify potential virulence factors in variant vaccine strains.

Amino Acid Substitution↗
PubMed2004

Varicella seroprevalence and molecular epidemiology of varicella-zoster virus in Argentina, 2002.

There is limited data on immunity against varicella-zoster virus (VZV) in adults in different parts of Argentina, and it is not known which VZV strains are circulating in Argentina. The objectives of this study were as follows: (i) to evaluate seroprevalence of varicella among adults, assessing the accuracy of clinical history and determining the sociodemographic factors associated with seropositivity; and (ii) to determine the VZV strains circulating in Argentina. A cross-sectional serological survey enrolling 2,807 women aged 15 to 49 years attending public health-care settings in four cities in Argentina (i.e., Buenos Aires, Salta, Mendoza, and Rosario) and one rural area was conducted from August to November 2002. Specimens for identification of VZV strains were obtained from vesicular lesions from 13 pediatric patients with varicella from different areas of the country. PCR amplification was used for genotyping. The overall seroprevalence of varicella antibodies was 98.5% (95% confidence interval, 98.0 to 98.9), ranging from 97.2% in central Buenos Aires to 99.3% in southern Buenos Aires and Salta. Varicella seroprevalence increased with age. Crowding and length of residence in the same place were associated with seropositivity. The positive predictive value of varicella history for immunity to varicella was 99.4%; however, the negative predictive value was 2.5%. The European genotype was identified in all viral specimens. In Argentina, seroprevalence in women more than 15 years old was high regardless of the area of residence. Negative or uncertain varicella history was not a good predictor of immunity. VZV genotype was stable in all areas of the country.

Adolescent↗
PubMed2004

Global identification of three major genotypes of varicella-zoster virus: longitudinal clustering and strategies for genotyping.

By analysis of a single, variable, and short DNA sequence of 447 bp located within open reading frame 22 (ORF22), we discriminated three major varicella-zoster virus (VZV) genotypes. VZV isolates from all six inhabited continents that showed nearly complete homology to ORF22 of the European reference strain Dumas were assigned to the European (E) genotype. All Japanese isolates, defined as the Japanese (J) genotype, were identical in the respective genomic region and proved the most divergent from the E strains, carrying four distinct variations. The remaining isolates carried a combination of E- and J-specific variations in the target sequence and thus were collectively termed the mosaic (M) genotype. Three hundred twenty-six isolates collected in 27 countries were genotyped. A distinctive longitudinal distribution of VZV genotypes supports this approach. Among 111 isolates collected from European patients, 96.4% were genotype E. Consistent with this observation, approximately 80% of the VZV strains from the United States were also genotype E. Similarly, genotype E viruses were dominant in the Asian part of Russia and in eastern Australia. M genotype viruses were strongly dominant in tropical regions of Africa, Indochina, and Central America, and they were common in western Australia. However, genotype M viruses were also identified as a minority in several countries worldwide. Two major intertypic variations of genotype M strains were identified, suggesting that the M genotype can be further differentiated into subgenotypes. These data highlight the direction for future VZV genotyping efforts. This approach provides the first simple genotyping method for VZV strains in clinical samples.

Cluster Analysis↗
PubMed2003

Identification of CD8+ T cell epitopes in the immediate early 62 protein (IE62) of varicella-zoster virus, and evaluation of frequency of CD8+ T cell response to IE62, by use of IE62 peptides after varicella vaccination.

Varicella-zoster virus (VZV) causes varicella, establishes neuronal latency, and can reactivate, resulting in herpes zoster. VZV-specific T cells are important for controlling infection. VZV immediate early protein 62 (IE62) is recognized by cytotoxic T cells from immune individuals, but no CD8(+) T cell epitopes have been defined for any VZV protein. CD8(+) T cell frequencies were assessed by cytokine flow cytometry (CFC), by use of synthetic-peptide pools corresponding to the IE62 sequence. IE62 peptide-specific CD8(+) T cells were below the threshold of detection, by direct CFC of either whole blood or peripheral blood mononuclear cells (PBMCs). Activated CD8(+)CD69(+) T cells that produced interferon-gamma were detectable after in vitro restimulation of PBMCs, and restricted epitopes were identified for HLA-A*0201-positive subjects. Varicella vaccination of 3 VZV-immune subjects was associated with increases in IE62 peptide-specific CD8(+) T cells, a finding indicating that in vivo re-exposure boosts memory immunity to this important viral protein.

Adolescent↗
PubMed2003

Prevalence of and risk factors for viral infections among human immunodeficiency virus (HIV)-infected and high-risk HIV-uninfected women.

Viruses that can persist in the host are of special concern in immunocompromised populations. Among 871 human immunodeficiency virus (HIV)-infected and 439 high-risk HIV-uninfected women, seroprevalences of cytomegalovirus, hepatitis B virus, hepatitis C virus, and herpes simplex virus types 1 and 2 and prevalence of human papillomavirus DNA in cervicovaginal lavage fluids were all >50% and were 2-30 times higher than prevalences in the general population. Prevalences were highest among HIV-infected women, of whom 44.2% had >or=5 other infections, and were relatively high even among the youngest women (age 16-25 years). In multivariate analyses, viral infections were independently associated not only with behaviors such as injection drug use and commercial sex but also with low income, low levels of education, and black race. Disadvantaged women and women who engage in high-risk behaviors are more likely to be coinfected with HIV and other viruses and, thus, may be at high risk of serious disease sequelae.

AIDS-Related Opportunistic Infections↗
PubMed2003

Postpartum varicella vaccination: is the vaccine virus excreted in breast milk?

OBJECTIVE: To evaluate whether the varicella vaccine virus is detected in breast milk after vaccination of breast-feeding women and whether there is serologic evidence of exposure of the infant to varicella virus after maternal vaccination. METHODS: We enrolled women identified as varicella seronegative during routine prenatal screening at Group Health Cooperative. Participants received the first dose of varicella vaccine at least 6 weeks postpartum and the second dose at least 4 weeks later. They collected ten breast milk samples after each vaccine dose. Breast milk samples were tested for varicella zoster virus by polymerase chain reaction (PCR). Serum specimens were collected from the mothers 1 month after each vaccine dose, and peripheral blood from their infants was collected onto filter spots 1 month after the mother's second dose. These samples were tested for varicella immunoglobulin (Ig) G by whole-virus enzyme-linked immunosorbent assay (ELISA), or by the more sensitive glycoprotein ELISA. When possible, filter spots from the infants were also tested by PCR for the presence of varicella zoster virus deoxyribonucleic acid (DNA). RESULTS: Twelve women were enrolled; all seroconverted after the first vaccine dose. Varicella DNA was not detected by PCR in any of the 217 postvaccination breast milk specimens. None of the infants was seropositive. Samples from six infants were tested for varicella zoster virus DNA by PCR, and all were negative. CONCLUSION: We found no evidence of varicella vaccine virus excretion in breast milk. These findings suggest that postpartum vaccination of varicella-susceptible women need not be delayed because of breast-feeding.

Adult↗
PubMed2003

A cluster of primary varicella cases among healthcare workers with false-positive varicella zoster virus titers.

BACKGROUND: Five cases of primary varicella zoster virus (VZV) we re diagnosed among hospital healthcare workers (HCWs). All had complied with a pre-employment VZV screening program and had been considered immune. OBJECTIVES: To summarize the investigation of VZV among un-immunized HCWs and to provide recommendations for avoiding false-positive serologic tests. DESIGN: Risk of transmission of VZV to susceptible HCWs is minimized through serologic screening. Varicella vaccine is recommended for susceptible HCWs. A commercially available latex bead agglutination assay (LA) is widely used because it is rapid and easy to perform. LA was compared with the whole-cell varicella ELISA standardized in the Centers for Disease Control and Prevention (CDC) National Herpes Laboratory. SETTING/POPULATION: Large inner-city, tertiary-employee population. RESULTS: In a year, 5 HCWs presented with laboratory-confirmed primary varicella infection. Four had VZV exposures 2 weeks prior to presentation. All had documented positive VZV titers by LA performed at hire. None were offered VZV vaccination. The original LAs were judged false-positives. INTERVENTION/FOLLOW-UP INVESTIGATION: Fifty-three consecutive VZV LA samples from the hospital laboratory were retested at the CDC. Forty-four samples concurred. Of the remaining 9, 4 were positive by hospital LA but negative by CDC IgG ELISA. Four were equivocal by hospital LA but negative by CDC IgG ELISA and LA. One was positive by hospital LA but negative by LA and equivocal by ELISA at the CDC. CONCLUSION: LA may be prone to false-positive results and inappropriate for screening hospital HCWs.

Adult↗
PubMed2002

Seroprevalence and correlates of herpes simplex virus type 2 infection in five sexually transmitted-disease clinics.

The seroprevalence of herpes simplex virus type 2 (HSV-2) infection was studied among 4128 patients from sexually transmitted disease (STD) clinics who were enrolled in a randomized controlled trial of human immunodeficiency virus and STD counseling efficacy. HSV-2 seroprevalence was 40.8% and was higher in women than in men (52.0% vs. 32.4%; P<.0001) and higher in blacks than in nonblacks (48.1% vs. 29.6%; P<.0001). Among 14-19-year-old patients, 36.8% of black women and 25.8% of nonblack women were infected with HSV-2. Independent predictors of HSV-2 seropositivity included female sex, black race, older age, less education, more lifetime sex partners, prior diagnosis of syphilis or gonorrhea, and lack of HSV-1 antibody. The majority of HSV-2-seropositive persons (84.7%) had never received a diagnosis of genital herpes. HSV-2 infection is common in STD clinic attendees in the United States, even among young age groups, especially among women. Efforts to prevent genital herpes should begin at an early age. The high rate of undiagnosed HSV-2 infection likely contributes to ongoing transmission.

Adolescent↗