Association of major histocompatibility complex determinants with the development of symptomatic and asymptomatic genital herpes simplex virus type 2 infections.
The clinical spectrum of herpes simplex virus (HSV) infections, ranging from asymptomatic to frequently distressing outbreaks, suggests that there may be immunologic determinants of disease severity that are associated with human leukocyte antigen (HLA) expression. A controlled, prospective study identified several major histocompatibility complex (MHC) class I and II antigens whose frequencies are associated with HSV-2 infection or with frequent symptomatic genital recurrences. Previous studies were hampered by the inability to serologically identify patients with asymptomatic HSV-2 infection. Clinical evaluation and Western blot assay were used to identify 3 subject cohorts: 1 with no prior HSV infections, 1 with HSV-2 antibodies but no recognized symptoms, and 1 with HSV-2 antibodies and frequent genital recurrences. Statistical comparisons of HLA frequencies among these cohorts showed associations of HLA-B27 and -Cw2 with symptomatic disease. Also, HLA-Cw4 was significantly associated with HSV-2 infection. These associations indicate that immunologic factors linked to the MHC influence the risk of HSV-2 infection and disease expression. (+info)
Control of STDs--the role of prophylactic vaccines against herpes simplex virus.
OBJECTIVES: To summarise the current status of genital herpes simplex virus (HSV) vaccine development and provide a discussion of the potential benefits and limitations of genital herpes vaccines. METHODS: Literature review. RESULTS: Genital herpes simplex virus infection has a complex pathogenesis that has contributed to it becoming a serious worldwide problem. In an attempt to control the problem five different types of genital herpes vaccines have been developed. These include inactivated virion derived vaccines, adjuvanted subunit vaccines, vectored vaccines, replication limited live viral vaccines, genetically attenuated live viral vaccines, and nucleic acid vaccines. While available commercially in some parts of the world, inactivated virion derived vaccines have not been proved effective. Of the others, adjuvanted subunit vaccines, replication limited live viral vaccines, and nucleic acid vaccines are currently in clinical trials and vectored vaccines and genetically attenuated live viral vaccines are in preclinical development. CONCLUSION: With regard to HSV vaccines in general, it is reasonable to expect that the newer vaccines may protect the individual from developing symptomatic genital herpes but may not protect against asymptomatic viral infection. With widespread use HSV vaccines might help to prevent the spread of genital herpes. (+info)
Comparison between virus isolation method, Papanicolaou stain, immunoperoxidase stain and polymerase chain reaction in the diagnosis of genital herpes.
Papanicolaou (Pap) stain, immunoperoxidase (IP) stain and polymerase chain reaction (PCR) were evaluated against the virus isolation method for their sensitivity and specificity in the diagnosis of herpes simplex virus (HSV) infection in 96 women who were suspected of genital herpes. The result showed that the sensitivity of PCR, IP and Pap stain was 100, 92.0 and 62.7%, respectively, while the specificity was 76.2, 66.7 and 81.0%, respectively. PCR was even more sensitive than the virus isolation technique. As Pap stain is the technique routinely performed for diagnosing genital herpes in most of the hospitals in Thailand, its low sensitivity should be taken into consideration. Based on the investigation by all four techniques together, HSV infection was diagnosed in 91.6% of the cases suspected of genital herpes which reflected higher precision of the clinical diagnosis over Pap stain. (+info)
Development of a high-throughput quantitative assay for detecting herpes simplex virus DNA in clinical samples.
We have developed a high-throughput, semiautomated, quantitative fluorescence-based PCR assay to detect and type herpes simplex virus (HSV) DNA in clinical samples. The detection assay, which uses primers to the type-common region of HSV glycoprotein B (gB), was linear from <10 to 10(8) copies of HSV DNA/20 microl of sample. Among duplicate samples in reproducibility runs, the assay showed less than 5% variability. We compared the fluorescence-based PCR assay with culture and gel-based liquid hybridization system with 335 genital tract specimens from HSV type 2 (HSV-2)-seropositive persons attending a research clinic and 380 consecutive cerebrospinal fluid (CSF) samples submitted to a diagnostic virology laboratory. Among the 162 culture-positive genital tract specimens, TaqMan PCR was positive for 157 (97%) specimens, whereas the quantitative-competitive PCR was positive for 144 (89%) specimens. Comparisons of the mean titer of HSV DNA detected by the two assays revealed that the mean titer detected by the gel-based system was slightly higher (median, 1 log). These differences in titers were in part related to the fivefold difference in the amount of HSV DNA used in the amplicon standards with the two assays. Among the 380 CSF samples, 42 were positive by both assays, 13 were positive only by the assay with the agarose gel, and 3 were positive only by the assay with the fluorescent probe. To define the subtype of HSV DNA detected in the screening assay, we also designed one set of primers which amplifies the gG regions of both types of HSV and probes which are specific to either HSV-1 (gG1) or HSV-2 (gG2). These probes were labeled with different fluorescent dyes (6-carboxyfluorescein for gG2 and 6-hexachlorofluorescein for gG1) to enable detection in a single PCR. In mixing experiments the probes discriminated the correct subtype in mixtures with up to a 7-log-higher concentration of the opposite subtype. The PCR typing results showed 100% concordance with the results obtained by assays with monoclonal antibodies against HSV-1 or HSV-2. Thus, while the real-time PCR is slightly less sensitive than the gel-based liquid hybridization system, the high throughput, the lack of contamination during processing, the better reproducibility, and the better ability to type the isolates rapidly make the real-time PCR a valuable tool for clinical investigation and diagnosis of HSV infection. (+info)
Seroprevalence of herpes simplex virus-type 2 in African-American college women.
This study examines the relationship between sexual behaviors and prevalence of herpes simplex virus-type 2 (HSV-2) among African-American college women. Subjects (n = 138) were recruited randomly from a state university to participate in a study regarding sexual attitudes and behaviors and to have their blood drawn for type-specific HSV seroprevalence. Sera were analyzed for 96 college women with a mean age of 21 years. Of the 96 women, 29 (30%) were HSV-2 seropositive. The results of this study revealed that a history of sexually transmitted disease was predictive of HSV-2 infection. Number of lifetime partners, however, was not related to HSV-2 seropositivity. Four (31%) of the 13 women who reported only one lifetime partner were seropositive. These findings indicate that for young African-American college women, the risk of being infected with HSV-2 is high even with only one lifetime partner. Behavioral strategies focused on decreasing the number of sexual partners are not likely to be sufficient in preventing the spread of HSV-2 infection among young African-American women. The development and use of alternative approaches to prevent the spread of HSV-2 among young African Americans should be considered. (+info)
The epidemiology of neonatal herpes simplex virus infections in California from 1985 to 1995.
Comprehensive hospital discharge data completed by the California Office of Statewide Health Planning and Development was used to determine whether the proportion of infants +info)
The topical microbicide PRO 2000 protects against genital herpes infection in a mouse model.
Vaginal gel formulations containing the naphthalene sulfonate polymer PRO 2000 are being developed as topical microbicides to protect against infection with sexually transmitted disease (STD) pathogens. A mouse model was used to determine whether PRO 2000 could protect against genital herpes in vivo. Animals received a single intravaginal application of 15 microL of a 10% PRO 2000 aqueous solution or a 4.0% or 0.5% PRO 2000 vaginal gel formulation 20 s prior to intravaginal challenge with 4.0 log10 pfu of herpes simplex virus type 2. Treatment with the 4.0% gel provided complete protection against infection; treatment with the 0.5% gel or 10% solution provided 81% and 80% protection, respectively. Furthermore, the 4% gel provided significant protection even when viral challenge was delayed until 60 min after treatment. This is the first report to show that PRO 2000 can protect against infection with an STD pathogen in vivo. (+info)
Immunization against genital herpes with a vaccine virus that has defects in productive and latent infection.
An effective vaccine for genital herpes has been difficult to achieve because of the limited efficacy of subunit vaccines and the safety concerns about live viruses. As an alternative approach, mutant herpes simplex virus strains that are replication-defective can induce protective immunity. To increase the level of safety and to prove that replication was not needed for immunization, we constructed a mutant herpes simplex virus 2 strain containing two deletion mutations, each of which eliminated viral replication. The double-mutant virus induces protective immunity that can reduce acute viral shedding and latent infection in a mouse genital model, but importantly, the double-mutant virus shows a phenotypic defect in latent infection. This herpes vaccine strain, which is immunogenic but has defects in both productive and latent infection, provides a paradigm for the design of vaccines and vaccine vectors for other sexually transmitted diseases, such as AIDS. (+info)