Noroviruses (NV) are transmitted by fecally contaminated food, vomit, and person-to-person contact. They are one of the main causes of non-bacterial acute gastroenteritis in nursing, old people and children’s homes. NV outbreaks are characterized by a short incubation period (12–48 h), nausea, vomiting and diarrhea, and high secondary attack rates. The illness is generally mild and self-limiting. The aim of diagnostic procedures in viral gastroenteritis is to avoid nosocomial infections on the one hand and unnecessary antibiotic treatment on the other. Diagnostic procedures for NV are based on the detection of virus in stool samples by (immune) transmission electron microscopy (TEM), antigen ELISA, or polymerase chain reaction (PCR). In our study, a total of 244 stool samples obtained from 227 patients between March and May 2002 were tested by TEM, antigen ELISA and in-house PCR. Our data showed that PCR has the highest sensitivity (94.1%), followed by TEM (58.3%), and ELISA (31.3%), while specificity was highest for TEM (98.0%), followed by ELISA (94.9%), and PCR (92.4%). All three methods tested (TEM, ELISA and PCR) are useful for epidemiological investigations in gastroenteritis outbreaks; however, to maximize diagnostic validity for individual cases, at least two of the methods should be combined.

Intracellular glutathione (GSH) plays an important regulatory role in the host response to viral infections. Replenishment of intracellular GSH is a desirable yet challenging goal, since systemic GSH supplementation is rather inefficient due to a short half-life of GSH in blood plasma. Further, GSH is not taken up by cells directly, but needs to be broken down into amino acids and resynthesized to GSH intracellularly, this process often being impaired during viral infections. These obstacles may be overcome by a novel glutathione derivative S-acetylglutathione (S-GSH), which is more stable in plasma and taken up directly by cells with subsequent conversion to GSH. In the present study, in vitro effects of supplementation with S-GSH or GSH on intracellular GSH levels, cell survival and replication of human herpes simplex virus type 1 (HSV-1) were studied in human foreskin fibroblasts. In addition, in vivo effects of supplementation with S-GSH or GSH on HSV-1-induced mortality were studied in hr/hr mice. In cell culture, viral infection resulted in a significant decrease of intracellular GSH levels. S-GSH efficiently and dose-dependently (5 and 10 mM tested) restored intracellular GSH, and this replenishment was more efficient than with GSH supplementation. In mice, S-GSH, but not GSH, significantly decreased HSV-1-induced mortality ( P<0.05). The data suggest that S-GSH is a suitable antiviral agent against HSV-1 both in vitro and in vivo, indicating that this drug may be of benefit in the adjunctive therapy of HSV-1 infections.

Herpes simplex virus (HSV) types 1 and 2 are widespread human infectious agents that are responsible for persistent and latent infections. HSV type 2 (HSV-2) infection is usually transmitted sexually, while HSV type I (HSV-1) is commonly acquired by saliva contact during childhood. In a retrospective study, sera from more than 4,800 patients were analyzed for HSV type-specific IgG antibodies. In people older than 15 years, the seroprevalence of HSV-1 showed no statistically significant discrepancy between the control group (76.3% in females and 75.2% in males), HIV-infected patients (82.8% in females and 84.3% in males), and organ transplant (OTX) recipients (90.3% in females and 86.3% in males) (P>0.05). Age-related analysis of the control group showed that there is an age-dependent increase of HSV-1 seroprevalence in both sexes, reaching its peak in those aged 40 years and older (women 85.4%, men 82.8%). The only age group in which there is a significantly higher seropositivity rate in women than in men is in those aged between 15 and 39 years, with 70.8% versus 63.7% (P<0.05). As with HSV-1, there is an age-related increase of the HSV-2 seroprevalence; however, this increase starts later in life, with the onset of sexual activity. The HSV-2 prevalence across all age groups was highest in female prostitutes (78.0%) and among HIV-infected patients (women 64.1%, men 54.3%); this contrasts with the control group (overall women 17%, men 12.5%; those above 15 years of age, women 18%, men 13.8%) and the OTX patients (women 22.6%, men 9.8%). In the control group the rate of positivity increases with age and peaks in the group older than 40 years (24.2% in women and 16.2% in men). In females the seroprevalence is always elevated compared with males. The data presented show that female sex and older age are independent predictors of HSV-2 seropositivity, while immunosuppression is not. Our additional data show no evidence of a statistically significant humoral HSV-1/HSV-2 cross-immunity. People with HSV-1 serum antibodies have no lower risk of HSV-2 seropositivity than those lacking antibodies to HSV-1. The same is true when investigating HSV-1 seroprevalence rates in HSV-2-seropositive or -negative individuals, retrospectively.

Infections with herpes simplex virus (HSV) types 1 and 2 are widespread in all human populations and result in persistent and latent infections. HSV-1 is commonly responsible for orofacial, HSV-2 more likely causes genital lesions. Herpes genitalis is one of the most important sexually transmitted diseases; furthermore, there are severe diseases associated with HSV (e.g., encephalitis). Over the last years an increase in clinical manifestations of HSV has been reported, and HSV-1 has been increasingly discussed as causative agent of herpes genitalis. We retrospectively evaluated the laboratory results of our routine diagnostic service for HSV infections, looking for changes of HSV epidemiology in recent years. Specimens from 2,678 herpes patients were obtained between 1 January 1996 and 31 March 2002. Using cell culture, the presence of HSV was investigated in swabs taken from different body sites, and clinical data on HSV localization and type were evaluated. We found 345 patients positive for HSV-1 and 212 positive for HSV-2. Clinical data were available from 72.1% of the patients with HSV-1, and 61.3% of those with HSV-2 infection. In genital herpes HSV-1 was the causative agent in 20% of men and in 25% of women. In patients suffering from orofacial herpes HSV-2 was detected in 7% of men and in 4% of women. To evaluate the frequency of neurological HSV diseases, 2,406 cerebrospinal fluid samples (CSF) from 2,121 patients suspected of meningitis or encephalitis were tested for HSV DNA by the polymerase chain reaction. Among those patients, 120 showed CSF positive for HSV DNA. Serum surveys of HSV-1 and HSV-2 infection recently established in our region were compared to similar studies performed in Germany 25 years ago. We found that seroprevalences have not changed over the last 25 years and that neurological HSV diseases are rare. However, as in the USA, a significant percentage of herpes genitalis is caused by HSV-1 in Germany.