|
Worldwide, the rate of HSV infection counting both (HSV-1) and (HSV-2) is around 90%. Although many people infected with HSV develop labial or genital lesions, the majority are either undiagnosed or display no physical symptoms—individuals with no symptoms are described as asymptomatic or as having subclinical herpes. In many infections, the first symptom a person will have of their own infection is the horizontal transmission to a sexual partner or the vertical transmission of neonatal herpes to a newborn at term. Since most asymptomatic individuals are unaware of their infection, they are considered at high risk for spreading HSV. Many studies have been performed around the world to estimate the numbers of individuals infected with HSV-1 and HSV-2 by determining if they have developed antibodies against either viral species. This information provides population prevalence of HSV viral infections in individuals with or without active disease. It has to be remembered that there are population subgroups that are more vulnerable for HSV infections, such as cancer chemotherapy patients. ==Europe== Large differences in HSV-1 seroprevalence are seen in different European countries. HSV-1 seroprevalence is high in Bulgaria (83.9%) and The Czech Republic (80.6%), and lower in Belgium (67.4%), The Netherlands (56.7%), and Finland (52.4%).〔 The typical age at which HSV-1 infection is acquired ranges from 5 to 9 years in Central and Eastern European countries like Bulgaria and the Czech Republic, to over 25 years of age in Northern European countries such as Finland, The Netherlands, Germany, and England and Wales. Young adults in Northern European countries are less likely to be infected with HSV-1. European women are more likely to be HSV-1 seropositive than men.〔 HSV-2 seropositivity is widely distributed in Europeans older than 12, although there are large differences in the percentage of the population exposed to HSV-2. Bulgaria has a high (23.9%) HSV-2 seroprevalence relative to other European countries: Germany (13.9%), Finland (13.4%), Belgium (11.1%), The Netherlands (8.8%), the Czech Republic (6.0%), and England and Wales (4.2%).〔 Women are more likely to be seropositive than men, and likely acquire the virus at an earlier age. In each country of Europe, HSV-2 seropositivity becomes more common from adolescence onwards and increases in the population with age, with a decline in the older age groups in some countries.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Epidemiology of herpes simplex」の詳細全文を読む スポンサード リンク
|