Detection, quantification and genotyping of Herpes Simplex Virus in cervicovaginal secretions by real-time PCR: a cross sectional survey

BACKGROUND: Herpes Simplex Virus (HSV) Genital Ulcer Disease (GUD) is an important public health problem, whose interaction with HIV results in mutually enhancing epidemics. Conventional methods for detecting HSV tend to be slow and insensitive. We designed a rapid PCR-based assay to quantify and type HSV in cervicovaginal lavage (CVL) fluid of subjects attending a Genito-Urinary Medicine (GUM) clinic. Vaginal swabs, CVL fluid and venous blood were collected. Quantitative detection of HSV was conducted using real time PCR with HSV specific primers and SYBR Green I. Fluorogenic TaqMan Minor Groove Binder (MGB) probes designed around a single base mismatch in the HSV DNA polymerase I gene were used to type HSV in a separate reaction. The Kalon test was used to detect anti-HSV-2 IgG antibodies in serum. Testing for HIV, other Sexually Transmitted Infections (STI) and related infections was based on standard clinical and laboratory methods. RESULTS: Seventy consecutive GUM clinic attendees were studied. Twenty-seven subjects (39%) had detectable HSV DNA in CVL fluid; HSV-2 alone was detected in 19 (70%) subjects, HSV-1 alone was detected in 4 (15%) subjects and both HSV types were detected in 4 (15%) subjects. Eleven out of 27 subjects (41%) with anti-HSV-2 IgG had detectable HSV-2 DNA in CVL fluid. Seven subjects (10%) were HIV-positive. Three of seven (43%) HIV-infected subjects and two of five subjects with GUD (40%) were secreting HSV-2. None of the subjects in whom HSV-1 was detected had GUD. CONCLUSION: Quantitative real-time PCR and Taqman MGB probes specific for HSV-1 or -2 were used to develop an assay for quantification and typing of HSV. The majority of subjects in which HSV was detected had low levels of CVL fluid HSV, with no detectable HSV-2 antibodies and were asymptomatic

First-year results of the Global Influenza Hospital Surveillance Network: 2012-2013 Northern hemisphere influenza season

Background: The Global Influenza Hospital Surveillance Network (GIHSN) was developed to improve understanding of severe influenza infection, as represented by hospitalized cases. The GIHSN is composed of coordinating sites, mainly affiliated with health authorities, each of which supervises and compiles data from one to seven hospitals. This report describes the distribution of influenza viruses A(H1N1), A(H3N2), B/Victoria, and B/Yamagata resulting in hospitalization during 2012-2013, the network's first year

Genetic characterization of influenza viruses from influenza-related hospital admissions in the St. Petersburg and Valencia sites of the Global Influenza Hospital Surveillance Network during the 2013/14 influenza season

AbstractBackgroundContinuous surveillance for genetic changes in circulating influenza viruses is needed to guide influenza prevention and control.ObjectivesTo compare intra-seasonal influenza genetic diversity of hemagglutinin in influenza A strains isolated from influenza hospital admissions collected at two distinct sites during the same season.Study designComparative phylogenetic analysis of full-length hemagglutinin genes from 77 isolated influenza A viruses from the St. Petersburg, Russian Federation and Valencia, Spain sites of the Global Influenza Hospital Surveillance Network (GIHSN) during the 2013/14 season.ResultsWe found significant variability in A(H3N2) and A(H1N1)pdm09 viruses between the two sites, with nucleotide variation at antigenic positions much lower for A(H1N1)pdm09 than for A(H3N2) viruses. For A(H1N1)pdm09, antigenic sites differed by three to four amino acids from the vaccine strain, two of them common to all tested isolates. For A(H3N2) viruses, antigenic sites differed by six to nine amino acids from the vaccine strain, four of them common to all tested isolates. A fifth amino acid substitution in the antigenic sites of A(H3N2) defined a new clade, 3C.2. For both influenza A subtypes, pairwise amino acid distances between circulating viruses and vaccine strains were significantly higher at antigenic than at non-antigenic sites. Whereas A(H1N1)pdm09 viruses clustered with clade 6B and 94% of A(H3N2) with clade 3C.3, at both study sites A(H3N2) clade 3C.2 viruses emerged towards the end of the season, showing greater pairwise amino acid distances from the vaccine strain compared to the predominant clade 3C.3.ConclusionsInfluenza A antigenic variants differed between St. Petersburg and Valencia, and A(H3N2) clade 3C.2 viruses were characterized by more amino acid differences from the vaccine strain, especially at the antigenic sites

2012-2013 Seasonal Influenza Vaccine Effectiveness against Influenza Hospitalizations: Results from the Global Influenza Hospital Surveillance Network

<div><p>Background</p><p>The effectiveness of currently licensed vaccines against influenza has not been clearly established, especially among individuals at increased risk for complications from influenza. We used a test-negative approach to estimate influenza vaccine effectiveness (IVE) against hospitalization with laboratory-confirmed influenza based on data collected from the Global Influenza Hospital Surveillance Network (GIHSN).</p><p>Methods and Findings</p><p>This was a multi-center, prospective, active surveillance, hospital-based epidemiological study during the 2012–2013 influenza season. Data were collected from hospitals participating in the GIHSN, including five in Spain, five in France, and four in the Russian Federation. Influenza was confirmed by reverse transcription-polymerase chain reaction. IVE against hospitalization for laboratory-confirmed influenza was estimated for adult patients targeted for vaccination and who were swabbed within 7 days of symptom onset. The overall adjusted IVE was 33% (95% confidence interval [CI], 11% to 49%). Point estimates of IVE were 23% (95% CI, −26% to 53%) for influenza A(H1N1)pdm09, 30% (95% CI, −37% to 64%) for influenza A(H3N2), and 43% (95% CI, 17% to 60%) for influenza B/Yamagata. IVE estimates were similar in subjects <65 and ≥65 years of age (35% [95% CI, −15% to 63%] vs.31% [95% CI, 4% to 51%]). Heterogeneity in site-specific IVE estimates was high (I² = 63.4%) for A(H1N1)pdm09 in patients ≥65 years of age. IVE estimates for influenza B/Yamagata were homogenous (I² = 0.0%).</p><p>Conclusions</p><p>These results, which were based on data collected from the GIHSN during the 2012–2013 influenza season, showed that influenza vaccines provided low to moderate protection against hospital admission with laboratory-confirmed influenza in adults targeted for influenza vaccination. In this population, IVE estimates against A(H1N1)pdm09 were sensitive to age group and study site. Influenza vaccination was moderately effective in preventing admissions with influenza B/Yamagata for all sites and age groups.</p></div

Pooled IVE in hospitalized patients swabbed within 7 days of symptom onset.

<p>CI, confidence interval; IVE, influenza vaccine effectiveness.</p>a<p>Site as a random effect.</p>b<p>Adjusted by week of symptom onset, age group, sex, hospitalization in the previous 12 months, presence of chronic conditions, and smoking habits.</p

Characteristics of patients included in the IVE analysis at each site.

a<p>Missing: St. Petersburg, n = 12; France, n = 1.</p>b<p>Missing: St. Petersburg, n = 11; France, n = 65.</p>c<p>Presented only for patients ≥65 years of age. No impairment defined as a Barthel score >60. Data missing: St. Petersburg, n = 13; Moscow, n = 37.</p

Number of admissions by epidemiological week at each site.

<p>The number of patients enrolled and included in the IVE analysis is shown by epidemiological week at each site for each influenza strain.</p

Heterogeneity of IVE estimates at each site for each age group.

<p>Heterogeneity of IVE estimates at each site for each age group.</p

Subjects included and excluded by coordinating site.

<p>Subjects included and excluded by coordinating site.</p

Characteristics of patients included in the IVE analysis by RT-PCR result.

<p><i>P</i>-values were determined by Pearson’s chi-square test. NC, not calculated.</p>a<p>N = 2158.</p>b<p>N = 2032.</p>c<p>N = 1069.</p>d<p>No impairment defined as a Barthel score >60.</p>e<p>Data on vaccination were exclusively from self-reporting for only 5.2% of all vaccinated patients. None of the patients with clinical records of vaccination self-reported not having been vaccinated.</p>f<p>N = 2168.</p