Herpes simplex virus antigen direct detection in standard virus transport medium by Du Pont Herpchek enzyme-linked immunosorbent assay

Investigating the survival of herpes simplex virus on toothbrushes and surrogate phallic devices

BACKGROUND

Herpes simplex virus-1 (HSV-1) is a member of the alphaherpesvirus (alphaherpesvirinae) subfamily, allowing it to affect a wide range of hosts. Herpes simplex virus-1 affects 3.7 billion people, or 67% of the population, under the age of 50. With a vast number of people infected by the virus, everyday objects are often contaminated with this agent. In this study we determined how long HSV-1 can remain viable on contaminated fomites.

METHODS

Fomites were selected for their use near potentially contaminated orifices and variable frequency of sanitization. Toothbrushes and surrogate phallic devices (SPDs) were cut, sterilized, and contaminated. After contaminating the fomites, we collected samples over a 24 h period, then used plaque assays to determine viral titers at prescribed time points.

RESULTS

The quantity of replication-competent virus present appears to decrease significantly 2 h post-contamination, then steadily declines over time, nearing zero at 24 h.

CONCLUSIONS

Our findings suggest that different surfaces influence HSV-1 survival. Proper cleaning must be performed for these types of fomites, especially if shared in an environment where someone with active genital or oral herpes lesions uses one of these fomites shortly after someone else.

2017 European guidelines for the management of genital herpes

Genital herpes is one of the commonest sexually transmitted infections worldwide. Using the best available evidence, this guideline recommends strategies for diagnosis, management, and follow-up of the condition as well as for minimising transmission. Early recognition and initiation of therapy is key and may reduce the duration of illness or avoid hospitalisation with complications, including urinary retention, meningism, or severe systemic illness. The guideline covers a range of common clinical scenarios, such as recurrent genital herpes, infection during pregnancy, and co-infection with human immunodeficiency virus.

A Novel Method to Titrate Herpes Simplex Virus-1 (HSV-1) Using Laser-Based Scanning of Near-Infrared Fluorophores Conjugated Antibodies

Among several strategies used for Herpes simplex virus (HSV) detection in biological specimens, standard plaque assay (SPA) remains the most reliable method to evaluate virus infectivity and quantify viral replication. However, it is a manual procedure, thereby affected by operator subjectivity, and it may be particularly laborious for multiple sample analysis. Here we describe an innovative method to perform the titration of HSV type 1 (HSV-1) in different samples, using the “In-Cell Western^TM” Assay (ICW) from LI-COR, a quantitative immunofluorescence assay that exploits laser-based scanning of near infrared (NIR). In particular, we employed NIR-immunodetection of viral proteins to monitor foci of HSV-1 infection in cell monolayers, and exploited an automated detection of their fluorescence intensity to evaluate virus titre. This innovative method produced similar and superimposable values compared to SPA, but it is faster and can be performed in 96 well plate, thus allowing to easily and quickly analyze and quantify many samples in parallel. These features make our method particularly suitable for the screening and characterization of antiviral compounds, as we demonstrated by testing acyclovir (ACV), the main anti-HSV-1 drug. Moreover, we developed a new data analysis system that allowed to overcome potential bias due to unspecific florescence signals, thus improving data reproducibility. Overall, our method may represents a useful tool for both clinical and research purposes.

The laboratory diagnosis of herpes simplex virus infections

Herpes simplex virus (HSV) types 1 and 2 cause genital herpes infections and are the most common cause of genital ulcer disease in industrialized nations. Although these infections are very common, the majority of them remain underdiagnosed because they are asymptomatic or unrecognized. A clinical diagnosis of genital herpes should always be confirmed by laboratory testing; this can be accomplished through the use of direct tests for viral isolation, the detection of antigen or, more recently, the detection of HSV DNA using molecular diagnostic techniques. Testing for serotypes is recommended because of the different prognostic and counselling implications. Type-specific HSV serology is becoming more readily available and will enhance the ability to make the diagnosis and guide clinical management in select patients.

European guideline for the management of genital herpes, 2010

This is the guideline for genital herpes simplex virus (HSV) management for the IUSTI/WHO Europe, 2010. They describe the epidemiology, diagnosis, clinical features, treatment and prevention of genital HSV infection. They include details on the management of HSV in pregnancy, those who are immunocompromised and the clinical investigation and management of suspected HSV-resistant disease.

Spin-amplified culture followed by enzyme immunoassay for detection of herpes simplex virus in patient specimens: a comparative study

In a comparative study it was found that a combination technique of spin-amplified culture and detection of herpes simplex virus (HSV) antigen in 48-h incubated cell culture lysate by a HSV antigen detection enzyme immunoassay kit (Dupont Herpchek) detected the largest number (227) of confirmed HSV positives when compared to standard cell culture (191) and direct Herpchek (146) on the same 415 clinical specimens.

Evaluation of ELVIS HSV ID/Typing System for the detection and typing of herpes simplex virus from clinical specimens

BACKGROUND

Herpes simplex virus (HSV) is a common pathogen with two serotypes: HSV-1 and HSV-2. HSV infection does not pose much of a threat to an immunocompetent host but to an immunocompromised host or a neonate the infection can be fatal. The Enzyme-Linked Virus Inducible System (ELVIS) employs a genetically altered baby hamster kidney (BHK) cell line that allows for the rapid overnight detection of HSV but also includes an immunofluorescent stain for the simultaneous detection and typing of HSV-1 and HSV-2.

OBJECTIVE

To evaluate the ELVIS HSV ID/Typing System in comparison with HSV identification and typing in primary rabbit kidney (PRK) cells grown in shell vials.

STUDY DESIGN

Over a period of 6 weeks, 130 specimens were submitted to the diagnostic virology laboratory and cultured for the presence of HSV. Two PRK shell vials and one ELVIS BHK shell vial were inoculated with patient specimen. PRK shell vials were observed for cytopathic effect (CPE) for up to 4 days. When CPE was observed the PRK shell vials were fixed and one shell vial was stained with HSV-1 monoclonal antibody (Mab) and the other was stained with HSV-2 Mab. The coverslips were observed under the fluorescent microscope for specific apple-green fluorescence. The BHK shell vials were incubated overnight, fixed, and stained with galactopyranoside (X-Gal). If blue cells were present, the specimen was positive for HSV. The coverslip was then observed under the fluorescent microscope for the presence of specific apple-green fluorescence, indicating HSV-2. If no specific apple-green stain was observed, the coverslip was stained with a fluorescent conjugated goat anti-mouse IgG to determine the presence of HSV-1.

RESULTS

Of the 130 specimens, PRK shell vials detected 43 positive HSV; 30 were HSV-2 and 13 were HSV-1. The ELVIS BHK shell vials detected 42 positive HSV; 30 were HSV-2 and 12 were HSV-1. One low titer specimen was not identified as being HSV positive. Two specimens were not directly typed by the ELVIS system. One specimen had only one blue cell present and did not show specific staining for either HSV-1 or HSV-2. The other specimen had only five blue cells present and only one fluorescent cell present that was difficult to type. As suggested by the manufacturer's instructions, both specimens that were not directly typed were re-grown overnight from their supernatants and were correctly identified and typed.

CONCLUSION

The ELVIS HSV ID/Typing System is a rapid, highly specific and sensitive method of overnight HSV detection and typing.

Rapid detection of HSV with an enzyme-linked virus inducible system™ (ELVIS™) employing a genetically modified cell line

BACKGROUND

Infections with herpes simplex viruses (HSV) are common and may cause severe disease in immunocompromised hosts and in neonates. Isolation of infectious HSV in tissue culture is the most sensitive method of detection, but is not the most rapid. Recently, however, an Enzyme-Linked Virus Inducible System (ELVIS) for rapid detection of HSV in culture has been developed. The system employs genetically engineered baby hamster kidney (BHK) cells (ELVIS cells) whose DNA bears and HSV inducible promoter gene chimerically linked to an E. coli LacZ "reporter" gene. Induction of the promoter by HSV leads to the production of LacZ product, beta-galactosidase, which is readily detected histochemically.

OBJECTIVE

To evaluate these ELVIS cells, as a test for HSV, in comparison with HSV detection in MRC-5 cells in shell vial cultures confirmed by staining with fluorescent antibodies.

STUDY DESIGN

Over a period of one month, 167 specimens submitted to the laboratory for detection of HSV were evaluated. Specimens were inoculated onto MRC-5 cells growing on glass coverslips in each of two shell vials and into two wells of a 24-well cluster plate containing ELVIS cells. MRC-5 shell vial cultures were observed daily for cpe for up to 7 days. With the appearance of cpe, the coverslips were fixed and the cells were typed for HSV-1 and HSV-2 with monoclonal antibodies. Specimens inoculated onto ELVIS cells were incubated for 16-24 h, then substrate was added to stain for beta-galactosidase. ELVIS cells, induced by HSV infection to express beta-galactosidase, stained blue upon reaction with substrate.

RESULTS

Of 167 specimens inoculated onto MRC-5 cells, 13 were excluded because of contamination or toxicity. Among the remaining 154 specimens, 24 were positive for HSV in the MRC-5 shell vials. Of 166 specimens inoculated into the ELVIS cell, all were completed within 24 h. Twenty-three (23) of the 24 shell-vial-positive cultures also were positive on the ELVIS cells. All 23 specimens detected in the ELVIS cells were positive within 24 h, whereas only nine were positive within 24 hours in MRC-5 shell vial cultures. The remaining 15 became positive after 24 h. Specimens positive for viruses other than HSV-1 or HSV-2 were not positive on the ELVIS cells.

CONCLUSIONS

The ELVIS assay for HSV is simple to perform, is rapid, sensitive, and specific. The assay detects both HSV-1 and HSV-2. No antibodies are required unless typing, which can be done on the ELVIS cells, is necessary.

Comparison of a direct antigen enzyme immunoassay, Herpchek, with cell culture for detection of herpes simplex virus from clinical specimens

Direct enzyme immunoassay (Herpchek) was compared with culture on 21,522 specimens mainly from asymptomatic women for herpes simplex virus detection. Sensitivity and specificity were 73.8 and 97.7%, respectively. The 33% detection rate by enzyme immunoassay in 5 h increased to 43% when the enzyme immunoassay was combined with culture. Herpchek alone was not sensitive enough, but in combination with culture, maximum detection was achieved.

Comparison of three monoclonal antibody-based enzyme immunoassays for detection of herpes simplex virus in clinical specimens

Three commercial monoclonal antibody-based enzyme immunoassays (Herpchek, IDEIA HSV and SureCell HSV) for detection of herpes simplex virus antigen were compared with isolation of virus in cell cultures. A total of 51 culture positive and 49 culture negative consecutively collected specimens that had been stored at -70 degrees C for a period of up to ten months were used in the study. Herpchek, IDEIA HSV and SureCell HSV assays gave a sensitivity of 88.2%, 82.4% and 47.1% respectively, and a specificity of 95.9%, 93.9% and 83.7% respectively compared to cell culture. A blocking antibody test showed that two culture negative specimens contained herpes simplex virus-specific antigens. If these two specimens were considered to be true positive, Herpchek, IDEIA HSV and SureCell HSV assays had a sensitivity of 88.7%, 83.0% and 47.2%, and a specificity of 100%, 97.9% and 85.1% respectively. The positive predictive value (using the resolved sample results) for Herpchek, IDEIA HSV and SureCell HSV was 100%, 97.8% and 78.1% respectively, and the negative predictive value 88.7%, 83.6% and 58.8% respectively. These results demonstrated that Herpchek and IDEIA HSV are sensitive and highly specific assays. Results could be obtained in less than five hours after receipt of specimens. SureCell HSV gave results in 15 minutes, but both the sensitivity and specificity were too low for this test to be considered as a substitute for culture.

Evaluation of new transport medium for detection of herpes simplex virus by culture and direct enzyme-linked immunosorbent assay

The transport medium Multi-Microbe Media (M4) was evaluated prospectively by culture and direct enzyme-linked immunosorbent assay (ELISA) for detection of herpes simplex virus from 473 specimens. In addition, 377 specimens in Bartels Viral Transport Medium were evaluated. By using culture as a "gold standard," the ELISA sensitivity was approximately 85%, while the specificities exceeded 96% for both media.

Laboratory techniques in the diagnosis of herpes simplex infection

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Evaluation of an automated immunodiagnostic assay system for direct detection of herpes simplex virus antigen in clinical specimens

The Vitek ImmunoDiagnostic Assay System (VIDAS) is a 2 1/3-h automated qualitative enzyme-linked fluorescent immunoassay developed for the direct detection of herpes simplex virus (HSV) antigen in clinical specimens. A total of 356 clinical specimens submitted for HSV isolation were prospectively evaluated with the VIDAS, and the results of the technique were compared with those of both HSV isolation in cell culture and Herpchek, a nonautomated enzyme immunoassay. Compared to cell culture, VIDAS had a sensitivity of 91.6% and a specificity of 89.3%, with positive and negative predictive values of 82.6 and 95.0%, respectively. In comparison to Herpchek, VIDAS had a sensitivity of 93.7% and a specificity of 93.0%, with positive and negative predictive values of 89.4 and 95.9%, respectively. The results demonstrated that the VIDAS required minimal manipulation in order to produce results comparable to those of Herpchek and HSV isolation in cell culture.

Management of genital herpes simplex infection

Herpes simplex infection of the genitals is a common condition, more often due to herpes simplex virus (HSV) type 2 than to type 1 virus. There is a severe first attack followed by mild recurrences which are more common and more frequent after HSV-2 than after HSV-1 genital infection. Clinical features with prodrome, vesicles and erosions may be characteristic allowing rapid clinical diagnosis. When possible laboratory confirmation should be attempted. General management includes simple hygiene, avoidance of sexual transmission, use of condoms, and notifying partners. Oral acyclovir (Zovirax, Wellcome) is the drug of choice for initial attacks and should be considered for all women with this diagnosis. Intravenous acyclovir may be used for very severe attacks. Men with initial attacks may be treated with oral acyclovir but mild disease affecting only skin may be treated with 5% acyclovir cream. Recurrences are short so acyclovir has less effect. Frequent recurrences can be troublesome and may be suppressed by continuous oral acyclovir, or individual attacks may be aborted with intermittent therapy. Various systemic complications may occur; an important but rare problem is primary herpes in late pregnancy. Acyclovir is effective in the treatment of the troublesome herpes simplex disease associated with human immunodeficiency infection. Acyclovir is one of the more expensive treatments for sexually transmitted diseases. At present in many countries costs are being examined, and application of the principles outlined here should help to minimize cost and maximize care.