“好”病毒和“坏”病毒 [复制链接]

How Many Outbreaks?
Just how much of a physical problem HSV poses for a person depends largely on three factors. The first is how well the person's immune system is able to control the infection.


Differences in immune response may be the main reason that some people are bothered by frequent cold sores or genital herpes outbreaks while others are not. It's also the reason that both HSV-1 and 2 can pose serious challenges for infants, who have a limited immune response; and for people with compromised immune systems, including people with cancer, AIDS, severe burns, and people taking immunosuppressant medications.


The second factor affecting outbreaks is how long a person has had the infection. Over time, recurrences of both HSV- 1 and 2 tend to decrease, for reasons that aren't entirely clear.

In the case of oral HSV-1, many of the approximately 100 million Americans who are infected acquired the virus when they were children. By the time they're adults, only some 5% of people are bothered enough to consider oral HSV-1 a medical problem, according to Spruance.


On the other hand, almost all of the approximately 40 million Americans infected with HSV-2 acquired the virus as teenagers or adults. In the first year, those who have recurring outbreaks experience an average of four to six episodes. Over time, as with oral infections, the number of outbreaks usually drops off.


A third factor influencing the frequency of HSV -1 and 2 outbreaks is whether the virus is established in its site of preference. While HSV can infect both genital and oral areas, both types cause milder infections when they are away from "home" territory. Outside their site of preference, both type 1 and 2 lose most of their punch.


For example, most people infected with HSV-1 in the genital area have few, if any, outbreaks after the initial episode, far fewer than is typical with either oral HSV-1 or genital HSV-2. While experts estimate that some 30% of genital herpes infections in the United States may be caused by HSV-1, only 2- 5% of recurring genital outbreaks are caused by HSV-1. Research conducted by Lawrence Corey, MD, and colleagues at the University of Washington in Seattle shows that genital HSV-2 recurs 10 times more often than genital HSV-1.


According to a study by Wald et al. (New England Journal of Medicine, 1995), among 110 women with genital herpes, the average number of recurrences per year for those with genital HSV-1 was zero. Other studies have shown an average of about one outbreak per year (Benedetti, Annals of Internal Medicine, 1994).


Similarly, HSV-2 infection in theoral area-outside its site of preference-very rarely causes problems. First of all, oral, HSV-2 infections are rare, for reasons discussed below. But even when an infection occurs, recurrent outbreaks are uncommon. In one study (Lafferty et al., New England Journal of Medicine, 1987), oral HSV-2 recurred an average of 0.01 times a year in newly infected people. "I've never convincingly seen an oral type 2 recurrence," says Spruance.


A possible fourth factor affecting recurrence rate is viral type. According to the Lafferty study, genital HSV-2 infections were the most frequently recurring herpes infections, followed by oral HSV-1, genital HSV-1, and last of all, oral HSV-2.

How Easily Spread?
As a number of readers have attested over the years, many people with genital herpes are at least as concerned about transmission-the likelihood of spreading the virus to a partner-as about their own health. On the other hand, few people with oral herpes, share this concern. Is this because one type is more contagious than the other?


The short answer is no. Both viral types are easily transmitted to their site of preference, and can also be spread to other sites. Both are most contagious during active outbreaks, but are often spread through viral shedding when there are no recognizable symptoms. According to Spruance, people with recurrent oral HSV-1 shed virus in their saliva about 5% of the time even when they show no symptoms. In the first year of infection, people with genital HSV-2 shed virus from the genital area about 6-10% of days when they show no symptoms, and less often over time. (Both of these figures reflect shedding as detected by viral culture.)


From here, however, the question of transmissibility gets more complicated. Acquisition of one type is more difficult-though certainly possible-if you already have the other type. This is because either type, contracted orally or genitally, causes the body to produce antibodies, some of which are active against both HSV-1 and 2. This acquired immune response gives some limited protection if the body encounters a second type. When a person with a prior HSV infection does contract the second type, the first episode tends to be less severe than when no prior antibodies are present.


On a practical level, this means oral HSV-1 is often the most easily acquired herpes infection. Usually the first herpes simplex virus that people encounter, oral HSV-1, is typically spread simply by the kind of social kiss that a relative gives a child. Because children have no prior infection with any HSV type, they have no immune defense against the virus.


By the time they're teenagers or young adults, about 50% of Americans have HSV-1 antibodies in their blood. By the time they are over age 50, some 80-90% of Americans have HSV-1 antibodies.


By comparison, almost all HSV-2 is encountered after childhood, when people become sexually active. Those who have a prior infection with HSV-1 have an acquired immune response that lowers - though certainly doesn't eliminate-the risk of acquiring HSV-2. According to one study (Mertz, Annals of Internal Medicine,1992), previous oral HSV-1 infection reduces the acquisition of subsequent HSV-2 infection by 40%.


A prior infection with oral HSV-1 lowers the risk of acquiring genital HSV-1 even further. Studies show that genital HSV-1 infections almost always occur in people who have no prior infection with HSV of either type (Corey, Annals of Internal Medicine, 1983).


In the absence of prior oral infection, however, HSV-1 spreads easily to the genital area, usually through oral sex. In some countries, such as Japan and parts of Great Britain, genital HSV-1 is as common as genital HSV- 2, or more common.


"Prevalence rates of genital HSV-1 differ based on the practice of oral sex and on the percentage of people who are HSV-1 positive from childhood," explains Anna Wald, MD researcher at the University of Washington at Seattle.


Finally, the question of immunity and HSV types is complicated by an additional issue. Some studies suggest that the ganglia themselves may acquire some immunity to HSV after they are exposed to one viral type.


In the laboratory, infection of ganglia with more than one virus is difficult, suggesting that it may be more difficult to acquire a second HSV type in a location where you already have HSV. A prior genital infection with HSV-1, for example, may give more protection against genital HSV-2 than a prior oral infection with HSV-1.


What does all this mean on a practical level? Let's look at some examples to find out. Say you have genital HSV-1 and your partner has genital HSV-2. If you have unprotected sex, there is a small but real risk that you will get HSV-2, resulting in more outbreaks and more shedding. "We have documented cases where a person acquires HSV-2 after a prior genital HSV- 1 infection," says Wald. "I don't think it happens often, but it does happen."


On the other hand, it's very unlikely that your partner will get genital HSV- 1 from you. "I've never seen a case of a person acquiring HSV-1 on top of HSV-2," says Wald. "It's possible, but it would be unusual."


What if your partner has genital HSV-2 and you perform oral sex on him or her? Will you get HSV- 2 in the mouth? Given the widespread practice of oral sex (some three-quarters of all adults practice it, according to The Social Organization of Sexuality, 1994) and the prevalence of genital HSV-2 infection, you might expect oral HSV-2 to be relatively common. It's not.


According to one study, almost 100% of recognizable HSV-2 infection is genital (Nahmias, Scandinavian Journal of Infectious Diseases Supplement, 1990). One reason is that most adults are already infected with HSV-1 orally, which provides some immunity against infection with HSV 2. Another reason is that oral HSV-2 rarely reactivates, so even if an infection does exist, no one knows.


So far we've been talking about transmission of HSV-1 or 2 from its site of preference. What about transmission from another site? Say you acquire genital HSV-1 through oral sex. Can you spread the virus to a partner through genital sex?


The answer is yes, but probably not as easily as it was spread through oral sex. The main reason is that the virus reactivates and sheds less often outside its site of preference. Only about one quarter of people with genital HSV- 1 shed virus at all in the absence of symptoms, while 55% of people with HSV-2 do (Wald, New England Journal of Medicine, 1995). "Shedding data appear to parallel recurrence data, meaning that people who have a lot of recurrences also have a lot of shedding," says Wald.


While HSV- 1 can be spread from genitals to genitals, "we think it is spread more easily through oral sex because HSV-1 reactivates more frequently in the oral area," says Wald. However, she warns, "transmission of genital HSV-1 during asymptomatic shedding has been documented." In other words, genital HSV-1 can be spread through genital sex, even when there are no symptoms. "Good" Virus/ "Bad" Virus


If HSV infection is as easily transmitted from the mouth as from the genitals, then why do people take steps to prevent genital but not oral infection? Why don't we kiss through dental dams ?


"It's ironic, isn't it?" says Wald. "It's not about health, it's about social acceptability."


Scientists can tell us all day that the main difference between the two viral types is simply their site of preference-whether they typically occur above the waist or below. But the unspoken attitudes of our society send a different message. That's just the problem, social attitudes whisper. Below the waist is bad.


"People think of oral herpes as the "good" herpes and genital herpes as the "bad" kind," says Glover of the National Herpes Hotline. "It's partly that they don't understand the similarities between HSV-1 and 2. But it's also that good and bad is how our culture views sex and our bodies."


The inescapable fact is that HSV-1 is usually spread through contact with infected lips, while HSV-2 usually spread through contact with infected genitals. From a social point of view, the problem is not the disease; it's how you got it.


Whether we like it or not, the social prejudice against genital herpes, no matter which virus causes it, is a reality. "People have more trouble explaining to a new partner that they have genital herpes, even if it's HSV- 1, than if they have a cold sore," says Glover. "Just saying the word "genital" is like an anvil that pulls the sentence down".


Is this topic making you crazy? For people who have trouble dealing with social attitudes toward genital herpes, the blatant double standard society applies to oral herpes can be frustrating, to say the least.


"Talk to a wise friend," suggests Rebecca, a health communication specialist on the National Herpes Hotline. "Join a support group. Find Someone you respect and exchange ideas them. It's always reassuring to see that not everyone lives inside the walls our society builds around sexual issues and realities. "


It's also worth hoping that new research on the similarities between HSV-1 and 2, as well as increased public education about genital herpes, can help lower the level of misunderstanding about both types of the virus. Today, the greatest difference between HSV- 1 and 2 appears to be the way we think about them. Tomorrow, that may change....

什么意思啊，谁给翻译一下啊

改天我空了翻译一下。

那要等到什么时候啊，期盼着啊

回复 6楼kumenshenghuo的帖子

关于hsv-1和hsv-2的事实（真相）
Hsv-1和hsv-2有多相像？我们来看一下关于两种病毒最新的科学事实，以及人们对于口唇和生殖器疱疹的看法。

当人们告诉别人自己有生殖器疱疹时，他们首先会将其与口唇疱疹对比。这种对比合适吗？尽尽管这是个科学事实，但是，社会舆论和情感态度，让生殖器疱疹很难客观的与口唇疱疹（很多人都感染）对比。于是，很多人都认为，hsv-1是“好病毒”，hsv-2是“坏病毒”。

我们咨询了领先的研究人员如何从严重性、复发、传染三个方面对比两种病毒。我们询问了两者在非“偏好”区域（也就是hsv-1在口唇，hsv-2在生殖器附近）复发频率，两者分别在生殖器部位的表现，以及感染其中一种后对另外一种的免疫性。

在显微镜下，hsv-1和hsv-2本质上是不同的，他们大约50%的DNA是相似的。两种病毒都是感染肌体粘膜表层，通常是在口唇和生殖器，并在神经系统潜伏。对于两种病毒，至少三分之二的感染人群没有症状，或者症状太轻微没有注意到。

两者最主要的区别是两种病毒潜伏的部位。Hsv-1通常潜伏在三叉神经节（耳朵附近），它通常复发在脸部、下唇。Hsv-2潜伏在骶神经节，复发在生殖器部位。

人们通常认为，hsv-1引起的症状较为轻微，但不危险。是这样吗？hsv-1通常是温和的，特别是感染口唇、脸、生殖器时。但是，在某些情况下，hsv-1复发在眼睛（可能致盲）。在某些情况下，hsv-1可能侵入脑部（可能致死）。有些会感染手指，胸部，脸部。

Hsv-1感染的范围和潜在的危险性让学者们开始正视它的危害。犹他大学的一位口唇研究专家Spotswood Spruance说：我认为hsv-1比起hsv-2来，更重要，hsv-1的危害远被低估了。

对比而言，hsv-2被认为是痛苦、危险的感染，而且只能性传播。是这样吗？22%的美国成年人（各阶层、各种族）患有hsv-2.就像hsv-1一样，hsv-2通常也是很温和，以至于很多人感觉不到。Hsv-2很少引起并发症，并传染到其他身体部位。

两种病毒表现的不同取决于是否潜伏在“偏好”区域。但是，两种病毒都很常见，通常不会对健康造成什么影响。这也就是为什么医生不会重视hsv-2，尽管确诊后对一个病人带来的精神压力。

虽然hsv对于部分人来说很折磨，很痛苦，但总体上，这个与其说是一个医学问题，不如说是社会问题。对于多数人而言，生殖器疱疹跟口唇疱疹差不多。

回复 2楼不孝之子的帖子

关于复发

疱疹病毒对一个人造成的危害取决于三个主要因素。

首先，免疫系统对病毒的反映不同，这就是为什么有些人会被反复复发困扰。这也是为什么疱疹病毒会对新生儿（免疫系统不完善）造成严重危害，对患有癌症、艾滋病、严重烧伤的人也是如此。

其次，病毒感染时间。随着时间的推移，复发会逐渐减少（原因现在未知）。对于口唇hsv-1,一亿的美国人在童年时代感染。当他们成年时，只有5%的人会当它是病。大约4000万美国人在十几岁或者成年后感染hsv-2.第一年，复发会达到4-6次。随着时间推移，就像口唇疱疹一样，复发次数会减少。

第三个因素是病毒是否在“偏好”区域。不同类型的疱疹病毒在离开偏好区域后，会变得温和，失去威力。例如，大多数人感染hsv-1在生殖器部位后，在过了初期之后很少复发，频率小于hsv-1口唇疱疹和hsv-2生殖器疱疹。专家估计，美国30%的生殖器疱疹是hsv-1引起的，只有2-5%的反复复发的生殖器疱疹是hsv-1导致。[屏蔽广告]顿大学西雅图分校的研究发现，hsv-2的复发频率是hsv-1复发频率（均是生殖器疱疹）的10倍。

根据一项研究（95年发表在新英格兰医学杂志），在110个感染生殖器疱疹的女性中，hsv-1每年的复发为0，其他研究发现，hsv-1生殖器疱疹平均复发每年不超过1次。

类似的，hsv-2感染的咽喉、口唇部位亦是如此。

此外，第四个可能的影响因素是病毒类型。根据研究，各类感染的复发频率为hsv-2生殖器>hsv-1口唇>hsv-1生殖器>hsv-2口唇。

回复 8楼1234qwer的帖子

如题

回复 9楼1234qwer的帖子

谢谢你啊，我很仔细的看了。辛苦了，兄弟！