Q5. How early can I take a test to determine if I caught herpes?
A. If there are fresh herpes lesions, the best diagnostic method is to take a sample from the sores to test for the virus, usually by culture. But when the culture is negative or if there are no lesions at the time, a blood test can detect antibodies to HSV – that is, the body’s reaction to the virus. However, it takes a few weeks for antibodies to develop. Most infected people have positive blood tests by 4 weeks after infection, but it can take up to 12 weeks and, rarely, up to 4-5 months. But about 90% of infected people become positive by 6 weeks. All this depends on having the right test; see Question 6.
问题5:最快多久可以通过检验来确定自己是否感染了疱疹?
回答:如果有已经发生的症状,最好的诊断是从症状处取样来检测病毒,通常医生采取的是“培养法”。但是如果通过“培养法”得出的诊断是阴性或当时没有发生疱疹的症状,则通过血清测试可以检测到是否血液中已产生HSV病毒的抗体,即身体对病毒的反应,从而判断是否感染了疱疹。然而,从身体感染了HSV病毒到产生出抗体,需要几周的时间。大部分感染者感染后需4周左右才能在血检中查出抗体阳性,但也有的最长需12周,甚至极少数人需4-5个月。但是约90%的人从感染到血检可以检出阳性的时间为6周。当然这一切都取决于准确的检验,参考问题6。
Q6. What blood tests are available to diagnose HSV infections?
Several blood tests are offered by various laboratories, and many health care providers don't know the differences between them. The accurate ones are the HerpeSelect test, produced by Focus Technologies; biokit-HSV-2, produced by Biokit USA; and the Western blot HSV test, which is used by research labs and isn't very often commercially available. Be sure that one of these was used; if not, then your result might be falsely positive. As of this writing (May 2005), no other test commercially available in the U.S. accurately distinguishes HSV-1 from HSV-2 infection. Happily, more and more laboratories in the U.S. now do the HerpeSelect test routinely. But if in doubt, ask the health care provider and be sure the right kind of test was done. (A common clue that the right kind of test wasn’t done is a result for “IgM” [immunoglobulin M] antibody. The accurate tests are only for IgG antibody; contrary to earlier beliefs, the presence or absence of IgM antibody to HSV-2 has no diagnostic value.)
问题6:哪种血清检查能够检测出HSV感染?
回答:有几种血清检测试剂由各个实验试使用,而很多诊所不了解他们的区别。精确的几种是Focus Technologies生产的Herpeselect,Biokit USA生产的Biokit-HSV-2,以及仅用于疱疹研究实验室而很少用于商业用途的Western blot的疱疹检测。(译者按:其中Herpeselect和Biokit-HSV-2是通过美国FDA-“FDA是美国食品药品管理局的缩写,相当于中国的卫生部,但比中国卫生部负责多了”-认证的。对于FDA认证的严格性、通过FDA认证的难度,以及通过FDA认证意味着什么,大家可以查询相关资料和文章。Western blot是最准确的,但是仅在美国一家大学内由科研实验室使用,并且成本非常高,不作为商业使用)接受检测时你必须确认医疗机构使用的是以上几种之一,否则你的检测结果很可能是不准确的。在这篇文章写作时(2006年11月),美国国内没有其他可供商业使用的检测试剂可以准确区分HSV感染者感染的是HSV-1还是HSV-2病毒。幸运的是目前美国越来越多的实验室已经将herpeselect检测作为常规检查项目(译者按:目前中国国内只有几家医院使用了Herpeselect,因此大部分医院用的试剂的准确性都不合格,这也就是为什么国内一些有责任心的医生不把血液检测结果做为诊断依据的原因,因为国内使用的试剂假阳性和假阴性都非常高,甚至准确率在50%以下,而他们大多数还未知道herpeselect产品,因此HSV的血检在国内很少普及。)如果怀疑你所接受检测的准确性,那就询问医疗机构是否用的是herpeselect检测。(最容易区分是否接受的是正确检测的办法是看检测结果上是否有IgM-immunoglobulin M抗体的检测结果,因为准确的测试只针对IgG抗体,原因简单的说是因为,检测Igm抗体的存在与否对于检测是否感染HSV-2没有意义。)(译者按:目前国内绝大部分医院HSV的检测结果仍分为IgM和IgG两项,其实是不正确的,因此只要看到检测结果上有IgM一项就说明这个检测是不科学的。)
Q7. How reliable is the HerpeSelect test? If I test negative should I still worry I have herpes?
A. Once enough time has passed for antibodies to develop – that is, 6-12 weeks, rarely up to 4-5 months - either a positive or negative result for HSV-2 in over 95% of people.
问题7:Herpeselect检测值得信赖吗?如果我检测结果为阴性我还用担心我是否感染了HSV病毒吗?
回答:只要时间过了抗体产生的最低时间(译者按:即窗口期,就是已感染病毒而体内尚未产生足够抗体以至血液检查无法检测出病毒抗体的这段时间),即6-12周,极少数人需要4-5个月,无论是阳性还是阴性结果其准确性都在95%以上。(译者按:herpeselect升级后,准确率已达到98%以上。)
以上资料是另一个朋友发的,从其中我们可以看到,说抗体会在四周左右才产生,那症状发作时,很多人都没有四周,就去查,这准吗?
另外就是,很多人说,半数以上的人在儿童或成年时都曾感染过HSV,那通过HSV查生殖器疱疹岂不是不太准了?