Vertical transmission of genital herpes: prevention and treatment options

Evaluation of anti-viral photodynamic therapy effects of different concentrations of 5-ALA using light irradiation on HSV-1

BACKGROUND

Herpes simplex virus (HSV) infections are prevalent worldwide, posing challenges due to asymptomatic carriage and recurrent outbreaks. Conventional treatments, including antiviral medications, are limited by drug resistance. Photodynamic therapy (PDT) offers a promising alternative, leveraging photosensitizers to induce viral inactivation via reactive oxygen species (ROS) generation upon light activation.

METHODS

This study investigates the efficacy of 5-aminolevulinic acid (5-ALA) as a photosensitizer in antiviral PDT against HSV-1. HSV-1 was treated with varying concentrations of 5-ALA and subjected to light irradiation at a 630 nm wavelength. Virus titers were assessed using the 50 % Tissue Culture Infectious dose (TCID50) assay. Six experimental groups were used: [1] Control (no 5-ALA or light), HSV-1 with 0.05 g/ml 5-ALA and 630 nm light, [2] HSV-1 with 0.05 g/ml 5-ALA (no light), [3] HSV-1 with 0.1 g/ml 5-ALA and light, [4] HSV-1 with 0.1 g/ml 5-ALA (no light), and [5] HSV-1 with light (no 5-ALA).

RESULTS

Virus treatment with 0.1 g/ml 5-ALA combined with light irradiation significantly reduced HSV-1 titer compared to control groups (p < 0.05). Specifically, the virus titer decreased from 10 6.3 TCID50/ml in the control group to 10 4.5 TCID50/ml in the treated group. However, lower concentrations of 5-ALA or light irradiation alone did not yield significant reductions in HSV-1 titer (p > 0.05). Group 4, receiving 0.1 g/ml 5-ALA with light irradiation, exhibited a significantly greater reduction in virus titer than group 2, receiving 0.05 g/ml 5-ALA with light irradiation (p < 0.05).

CONCLUSIONS

5-ALA-mediated PDT demonstrates selective antiviral efficacy against HSV-1, particularly at higher concentrations coupled with light irradiation. These findings underscore the potential of 5-ALA-based PDT as a promising approach for HSV-1 treatment, especially in cases of drug-resistant strains and immunocompromised individuals. Optimization of dosage and treatment protocols is essential for maximizing effectiveness in clinical applications, highlighting the need for further research in this area.

Herpes Simplex Virus Infection in Infants: 13 Year Evaluation (2005-2017) of Laboratory Confirmed Cases in Queensland, Australia

BACKGROUND

National neonatal surveillance for herpes simplex virus (HSV) disease suggests that the incidence of HSV disease may be higher in Queensland (QLD) than in other Australian States. We sought to investigate the incidence via a retrospective 13-year evaluation of statewide laboratory data, autopsy data and linked clinical records of infants with laboratory confirmed infection.

METHODS

All positive polymerase chain reaction HSV 1 and 2 results were obtained for infants 0-3 months of age from January 1, 2005 to December 31, 2017. Clinical data were obtained from patient records and parent questionnaires were used to evaluate long-term sequelae.

RESULTS

One hundred seventy-two infants with HSV positive polymerase chain reaction results: 121 (70.3%) with HSV 1. Of 104 (60.5%) infants with signs of HSV disease, 76 (73.1%) were neonates (≤28 days of age) [incidence 9.6 (95% confidence interval, 7.0-11.5) per 100,000 live births] and 28 (26.9%) were young infants (29-90 days of age) [3.6 (95% confidence interval, 2.4-5.4) per 100,000 live births]. The annual incidence of neonatal HSV disease increased significantly in Queensland over the study period (P < 0.01). Of the 76 neonates with HSV disease, 58 (76.3%) presented with the skin, eye, mouth (SEM) disease, 17 (22.4%) with HSV encephalitis and 11 (14.5%) had disseminated disease. Young infants presented with HSV skin, eye, mouth disease (21, 75.0%) or HSV encephalitis (6, 21.4%). Death occurred in 12/104 (11.5%) infants (all neonates) with 10 attributable to HSV disease.

CONCLUSION

The incidence of neonatal HSV disease in QLD is almost 3 times the national reported incidence. Further research is being undertaken to explore reasons for this change and implications for practice.

Acyclovir in the Treatment of Herpes Viruses – A Review

Background:

Herpes Simplex (HSV) viruses are widely spread, highly contagious human pathogens. The statistics indicate that 50-90% of adults worldwide are seropositive for these viruses, mainly HSV-1 and HSV-2. The primary infection results in the appearance of watery blisters (cold sores) on the skin, lips, tongue, buccal mucosa or genitals. The ocular infection is the major cause of corneal blindness in the Western World. Once the HSV virus enters human body, it cannot be completely eradicated because HSV viruses are able to change into their latent form which can survive the treatment. The viron resides in trigeminal ganglia of the host, who becomes vulnerable to the reoccurrence of the disease during the whole lifespan. The neurotropic and neuro-invasive properties of HSV are responsible for neurodegenerative illnesses, such as Alzheimer's disease. Acyclovir and its analogues, being the inhibitors of the viral DNA replication, are the only approved medicines for HSV infection therapies.

Objective:

The current paper presents the up-to-date overview of the important pharmacological features of acyclovir, its analogues and their delivery systems including the mechanism of action, routes of administration, absorption and metabolism, as well as side effects of the therapy.

Conclusion:

Acyclovir remains the gold standard in the treatment of herpes virus infections, mainly due to the emerging of the new delivery systems improving considerably its bioavailability. The analogues of acyclovir, especially their esters, characterized by significantly higher bioavailability and safety, may gradually replace acyclovir in selected applications.

Risks associated with viral infections during pregnancy

Despite the prevalence of viral infections in the American population, we still have a limited understanding of how they affect pregnancy and fetal development. Viruses can gain access to the decidua and placenta by ascending from the lower reproductive tract or via hematogenous transmission. Viral tropism for the decidua and placenta is then dependent on viral entry receptor expression in these tissues as well as on the maternal immune response to the virus. These factors vary by cell type and gestational age and can be affected by changes to the in utero environment and maternal immunity. Some viruses can directly infect the fetus at specific times during gestation, while some only infect the placenta. Both scenarios can result in severe birth defects or pregnancy loss. Systemic maternal viral infections can also affect the pregnancy, and these can be especially dangerous, because pregnant women suffer higher virus-associated morbidity and mortality than do nonpregnant counterparts. In this Review, we discuss the potential contributions of maternal, placental, and fetal viral infection to pregnancy outcome, fetal development, and maternal well-being.

Herpes Simplex Virus: Beyond the Basics

One of the most common sexually transmitted infections is the herpes simplex virus (HSV) Type 2. Although the incidence of newborn infection is not as common as in adults, approximately 1,500 neonates are diagnosed annually with HSV infection. HSV can be detrimental to the life of a newborn, with morbidity and mortality rates of up to 65 percent. This article addresses the maternal and fetal complications of HSV and the impact of HSV on the newborn along with diagnostic evaluation methods. In addition, treatment options and evidence-based practices regarding HSV are defined. Despite growing technology and medical treatment for early identification of HSV, this virus remains challenging and can deeply impact the life of an infant and his or her family. Early diagnosis, treatment, and intervention of an infant with HSV are crucial to ensure the livelihood of the newborn.

In vitro studies of the antiherpetic effect of photodynamic therapy

The number of viral infection cases in the Department of Gynecology and Obstetrics has tended to increase over last few years. Viruses form herpesvirus and cytomegalovirus families are associated with an increased risk for recurrent pregnancy loss. Photodynamic therapy (PDT) is a promising new approach to treat viral infections in which viral particles are inactivated. It exhibits great therapeutic potential, particularly among this group of patients. This study examined the use of PDT to treat herpesvirus infection (HVI) using an in vitro model. In this study, we used the Vero сell lineage as a suitable model of HVI, strains of HSV-1 (strain VR-3) and HSV-2 (strain MS) obtained from The National Virus Collection (London, UK), the photosensitizer Fotoditazine (Veta-Grand, Russia), an AFS physiotherapeutic device (Polironic Corporation, Russia). Laser light irradiation and the photosensitizer had different cytotoxic effects on the Vero cell cultures depending on the doses used. The optimal laser light and photosensitizer doses were determined. PDT had an antiviral effect on an in vitro model of HVI in cell culture. PDT has been shown to be effective treatment for HVI in vitro, leading to a reliable decrease of viral titer.

Neonatal herpes disease following maternal antenatal antiviral suppressive therapy: a multicenter case series

OBJECTIVE

The goal was to describe herpes simplex virus (HSV) disease in neonates whose mothers received suppressive acyclovir therapy for HSV infection.

STUDY DESIGN

A multicenter case series of 8 infants who developed neonatal HSV disease following maternal antiviral suppressive therapy during pregnancy.

RESULTS

Eight infants were identified from New Jersey (5), Maine (1), New York (1), and Texas (1) between 2005 and 2009. All 6 mothers of infants infected with HSV who were screened prenatally for group B Streptococcus were positive; 1 mother was not tested and the other had bacterial vaginosis and genital human papillomavirus infection. Six mothers had a first clinical episode of genital HSV infection during this pregnancy; mothers with a prior history of genital HSV had no clinically recognized outbreak during the pregnancy. Perinatal transmission of HSV occurred in 7 infants (despite suppressive therapy until the day of delivery in 5 instances). Seven of 8 patients were born at term; 6 infants were male. In 7 of 8 cases, HSV was diagnosed by 8 days of age. Five infants had skin, eye, and mucous membrane disease, 2 had central nervous system disease (without and with disseminated disease), and one had intrauterine/disseminated disease.

CONCLUSIONS

Although maternal antiviral suppressive therapy is an increasingly wide practice, physicians caring for neonates should be aware that suppressive therapy does not prevent neonatal HSV disease, which can have an atypical clinical presentation and drug resistance.

Early events in herpes simplex virus lifecycle with implications for an infection of lifetime

Affecting a large percentage of human population herpes simplex virus (HSV) types -1 and -2 mainly cause oral, ocular, and genital diseases. Infection begins with viral entry into a host cell, which may be preceded by viral “surfing” along filopodia. Viral glycoproteins then bind to one or more of several cell surface receptors, such as herpesvirus entry mediator (HVEM), nectin-1, 3-O sulfated heparan sulfate (3-OS HS), paired immunoglobulin-like receptor α, and non-muscle myosin-IIA. At least five viral envelope glycoproteins participate in entry and these include gB, gC, gD and gH-gL. Post-entry, these glycoproteins may also facilitate cell-to-cell spread of the virus, which helps in the evasion of physical barriers as well as several components of the innate and adaptive immune responses. The spread may be facilitated by membrane fusion, movement across tight junctions, transfer across neuronal synapses, or the recruitment of actin-containing structures. This review summarizes some of the recent advances in our understanding of HSV entry and cell-to-cell spread.

Immunization with a dominant-negative recombinant Herpes Simplex Virus (HSV) type 1 protects against HSV-2 genital disease in guinea pigs

Background

CJ9-gD is a novel dominant-negative recombinant herpes simplex virus type 1 (HSV-1) that is completely replication-defective, cannot establish detectable latent infection in vivo, and expresses high levels of the major HSV-1 antigen glycoprotein D immediately following infection. In the present study, CJ9-gD was evaluated as a vaccine against HSV-2 genital infection in guinea pigs.

Results

Animals immunized with CJ9-gD developed at least 700-fold higher titers of HSV-2-specific neutralization antibodies than mock-immunized controls. After challenge with wild-type HSV-2, all 10 control guinea pigs developed multiple genital lesions with an average of 21 lesions per animal. In contrast, only 2 minor lesions were found in 2 of 8 CJ9-gD-immunized animals, representing a 40-fold reduction on the incidence of primary genital lesions in immunized animals (p < 0.0001). Immunization significantly reduced the amount and duration of viral shedding and provided complete protection against neurological symptoms, while 90% of mock-immunized animals succumbed due to the severity of disease. Importantly, immunized animals showed no signs of recurrent disease or viral shedding during a 60-days observation period after recovery from primary infection, and carried 50-fold less latent viral DNA load in their dorsal root ganglia than the surviving mock-vaccinated controls (p < 0.0001).

Conclusions

Collectively, we demonstrate that vaccination with the HSV-1 recombinant CJ9-gD elicits strong and protective immune responses against primary and recurrent HSV-2 genital disease and significantly reduces the extent of latent infection.