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关于艾滋病病毒自助检测的常见问题
2009年08月19日16:20
1．请问试纸检测的准确性如何？
这个问题也就是关于试纸假阴性或假阳性问题，也即敏感度和特异度问题，根据国家试验室对12038份一般人群血样的应用来看，试纸检测全部阴性，同时用ELISA试剂盒参比检测，发现假阳性3例（经确认试验为阴性）。
同时,我们还对本实验室中留存的10份已明确的HIV阳性血清，用试纸进行测定，结果全部为阳性。综上，可见试纸的敏感度和特异度了，当然并不能说是100%，因为可能我们实验的样本量还不够大。从国家药局监督管理局提供的数据是敏感度 99.73%，特异度98.81%(官方最新公布数据)，对任何一种检验方法来说，这已经是相当不错了。
注：血检试纸在检测时均可在常规环境中进行，不需要特别的实验环境，也不需要加入其他任何特别试剂
2．HIV试纸的原理是什么？
本试纸条是采用胶体金免疫层析技术研制的新一代检测试剂，可检测血清或血浆标本中的HIV-1/2特异性抗体。整个操作时间仅需15分钟，操作简便、快速、准确、自带质控对照、不需任何附加试剂。适用于临床检验、无偿献血现场筛查等。其原理是：
在硝酸纤维素膜上的检测区包被基因重组的HIV--1+2 抗原，在对照区包被抗HIV 抗原单克隆抗体。检测时样品中的抗HIV 抗体与标记胶体金的基因重组HIV--1+2 抗原形成Ag-Au复合物，由于层析作用，复合物沿膜带移动，可与包被的基因重组HIV--1+2 抗原形成双抗原夹心免疫复合物。如为阳性样品，则可分别在检测区和对照区各凝集形成一条红色线，如为阴性样品，则只在对照区形成一条红色线。
3．阳性(+)结果的意义是什么？
试纸上出现两条红线，表示血液HIV抗体阳性。说明样品血液被高度怀疑为HIV感染，若要最终确认，需要做Western-Blot试验，当然这个试验需要由省一级或以上的艾滋病检测实验室才能完成，并出具检验报告，其它任何医疗单位所做的HIV检测都只与本试纸检测具有相同的意义。您如果检测到阳性结果，请及时与版主联系，进行确认试验。不过您不用担心，这个检测的灵敏度和特异度已经相当高了，基本不会与确认试验有出入。其实几乎所有人运用这一试验已经足够，因为其阴性结果的可靠性足以令你欣慰，下面我们要讲到。
4．阴性(-)结果的意义是什么？
试纸上仅出现一条红线（对照线），表示血液HIV抗体阴性。说明样品血液未被HIV感染，受试者可以放心了。但是有一点需要说明，在“空窗期”（高危行为后3个月以内）以内检测到的阴性结果可能不正确，因为在这段时期中，人体对HIV感染还没有产生足以被检测到的抗体。因此，“空窗期”以后，最好6 个月以后检测得出的阴性结果才可使受试者完全放心。
5．如果试纸未出现红线怎么办？
说明试验失败。可能的原因是：未按操作程序进行操作，或试纸本身存在质量问题（极少）,请另取试纸卡进行检测。
6．全血检测和血清检测有不同?
关于全血和血清检测，只要判定结果时间不超过30分钟，两者无差别。为什么呢？因为样品在醋酸纤维薄膜上层析的过程中，血液中的各组分扩散速度不一，当血清中的HIV抗体到达检测区，并使区带显红色时，血浆中的血红蛋白还没有到达检测区，这时（30分钟内）判定结果，没有什么问题。超过30分钟，本身带红色的血红蛋白也到达检测区，对非专业人士来说，这将对结果判定带来一点混淆，不过其实这也不难鉴别，只要应用过一次试纸，就会明白，真正的阳性（红色）检测线是横向的，血红蛋白产生的红色混淆比较乱，而且是纵向的，从底部向上延伸的。可是全血检测的好处还是相当明显的，只要1-2滴血，非常方便。对医院或防疫站来说，可以结合其他的血液检测项目进行，用血清，就不需要重复采血了。当然，96份试纸价格比96孔的ELISA试剂要贵，这也是医疗卫生单位没有大量采用的原因吧。
7．血检测试纸具有传染性吗?
最近有一些朋友来邮来电告诉我们,这几天有一个私人网站上说:"血检试纸含有艾滋病病毒,具有传染性",问我们是否是这样.我们一听觉得非常可笑, 有点医学知识的人都知道,各类试纸在包装前都要进行一道工序,那就是"灭菌实验",更何况试纸中根本就不含有艾滋病病毒,何来传染性,如果大家还不明白的话,你这样想一下就明白了:假设试纸是靠艾滋病病毒来做检测的,同时大家都知道艾滋病在离开人体后的数小时至数天就会死亡,那么大家想一想,在试纸上的" 病毒"还怎么存活下去? 这样的实验还怎么进行下? 难倒"病毒"在离开人体后还能存活?不然何来传染性呢? 所以大家只要想一想,关于一些个别的人编造出一些血检试纸具有传染性的说法,是对消费者,对社会极度不负责任的做法,至于做实验进医生们为什么要戴手套，其实这个很简单，因为这是接触的血制品（医生在接触所有血制品都会戴防护手套，但自己给自己做检测时是不需要的），主要是为了防止血制品交叉感染而采取的措施，所我们一再强调大家做检测时一定不要多人交叉使用采血检测工具，而并非一些人所讲的试纸具有传染性！
8．关于稀释液的使用说明
个人在利用试纸做检测时,如果检测顺利进行,就不要加入稀释液,如果要加最好也不能超过一到二滴,如果超过二滴稀释液,你的检测结果就无法得到保障了,就有很大的可能是假阴性,这个原因是很简单的,当血液中含有HIV抗体时,当浸至T处时,试纸T处的特殊物质就与与抗体发生色变反应,从而是现出T 线,如果你加入了稀释液抗体浓度就会大大降低,从而增加出现假阴性的机会.所以建议各朋友在做检测过程中,如果检测顺利进行就不要加入稀释液,就是要加入一定不要超过二滴,最好是一滴,否则,将大大降低检测的灵敏性,从而造成大量假阴性,对那种非专业人员大量鼓励在检测过程中加入稀释液的说法是对社会对科学对消费者极其不负责任的行为,不管其出发目的是什么,这都是值得社会广大群众谴责的.
9．与ELISA方法比较，试纸检测的优缺点？
两者的敏感性与特异性几乎无差别，ELISA多用于对人群的批量筛检，每一块酶联板一次可以检测92人份样品，其单人的价格就相对便宜一些。但是，若一块板子只用于检测10人以内，则价格又太贵。并且操作步骤多，必须有专业人员完成。而试纸检测应用方便，无须复杂步骤，个人能独立完成，判定方法简单，只是价格稍贵一些。
10．唾液可以检测吗？
目前为止，还没有应用唾液作为检测样品的试纸。
11．用尿液可以检测艾滋病吗?
到目前为止,已由美国卡普里特公司与美国剑桥生物科技公司合作生产出艾滋病尿检测试纸,同时他也是目前世界上唯一能生产该试纸的厂家, 不足的是该试纸在检测由HIV1型病毒已引的感染准确性较高，对HIV2病毒引起的感染试纸检测的灵敏度较低, 不能十分准确的检测到是否被HIV2型及其亚型病毒感染, 所以其检测准确度相对目前通用的血检试纸要低一些,同时HIV尿检试纸目前的假阳性偏高,目前国家还没有正式推荐使用。
12．艾滋病尿检测试纸与血检试纸有何区别?
艾滋病尿检测试纸与血检试纸的主要区别为: 尿检试纸能比较准确能检测出由HIV1型病毒已引的感染,不能十分准确的检测到是否被HIV2型及其亚型病毒感染,其对HIV2型病毒感染检测的准确度不高,但其最大的特点就是操作方便,不需血; 血检试纸由于生产技术已相当成熟,HIV1、HIV2型病毒引起的感染，该试纸均能准确地检测，其准确度高达99.73%,其不足点就是需要采血,在采血过程中如果多人交叉使用同一采血工具,易造成交叉感染,所以在做血检采血时,采血工具不能交叉混合使用,必须做到各人一份,单独使有.正因为血检试纸的准确度几乎高达100%,所以被所有国家广范推广使用!两种试纸的操作方法完全一样，只是取的样品不同。
13．用试纸检测的结果,我可以完全放心吗
一些朋友来信经常问我们,用试纸检测而得出的结果,是不是可以完全放心,针对这个问题我们前面也作过一些说明,经卫生部HIV预防与控制中心,解放军HIV确认实验室,北京地坛医院等六家权威检测机构抽检3327份血液样本验证,血检试纸的综合检测准确率在99.8%以上，广大地方医院及防疫站广泛使用检测试纸作为艾滋病抗体初步检测的快速诊断方法，检测结果是完全可以放心的。
14．HIV抗体检测准确度有没有可能达100%?
这是一个大家都较为关心的问题, 也常有一些恐艾的朋友前来咨询,不过专家要告诉大家的任何通过抗体来检测的实验,其准确是不可能达到100%, 有点医学知识的人都道任何通过抗体来检测的实验都是避免不了出现假阳性的情况(当然HIV检测也不例外), 也就是说当你体内产生了HIV抗体时,从医学的角度来讲并不代表你感染了HIV病毒, 如果有人说对你说其HIV抗体检测准确度高达100%,那肯定是骗人的, 不过可以肯定的是当你体内HIV抗体检测为阴性时(窗口期外),肯定是100%没有被HIV病毒感染,这也就是为什么艾滋病检测要分为初诊（抗体检测）、确诊（病源学）两个步骤。从目前市场上来看，HIV检测试纸进口的要大大优于国产的，由于尿检试纸目前不能十分准确的检测到是否感染HIV2及其亚型病毒，其检测准确度相对血检试纸会低一些.
人们会通过以下方式感染艾滋病：
A．无保护的性行为
如果一个人和一位艾滋病感染者发生性行为而不使用安全套的话，他就可能感染艾滋病。性行为包括阴道性交和肛门性交。
理论上讲，不用安全套（男性）或如牙套、女用安全套或塑料膜等遮挡物（女性）口交的时候也会传染艾滋病和其它性病。
B．不安全的血液、共用注射器和使用未正确灭菌的医疗器械
如果一个人与艾滋病感染者共用针头或者注射器用于静脉吸毒、取血或者任何有刺穿皮肤行为的活动，他/她都可能会被感染。用于刺穿或纹身的工具也会有一些传染艾滋病的风险。
输入感染艾滋病病毒的血液也会感染艾滋病。
如注射器和解剖刀之类的外科设备，甚至是使用过的用于静脉注射和血液传输的设备如果未经正确的消毒，都可能会传播艾滋病。
C．母婴传播：
母亲如果是感染者的话，可能会通过怀孕、分娩和哺乳的过程传染给孩子。
★ 社会性别与艾滋病：从艾滋病的传播来讲，女性易感艾滋病，一方面是生理特点，另一方面源于社会性别的不平等。
社会性别是相对于生理性别的一个概念，是指因社会、经济和文化影响而后天形成的男女之间的社会差异与权力关系，以及由此而产生的社会对男女群体特征、角色、活动、责任的期待和规范。
社会性别不平等使女性更易感艾滋病，具体表现在：女性在家庭内地位的不平等，女孩受教育权不能自主，女性没有经济自主权，性文化观念制约女性等，导致女性在选择性关系和性行为时受到很多限制，在感染后不能及时发现或者发现后无法得到及时的治疗。
什么是艾滋病？
艾滋病的全称为获得性免疫缺陷综合症，英文简称AIDS，音译为艾滋病。艾滋病是在感染了艾滋病病毒HIV之后引起的人体免疫能力不足而导致的不良健康状况疾病。艾滋病病毒通过破坏抵御各种疾病的免疫系统来攻击人体。
经过一段时期，免疫系统功能低下，人体就失去了抵抗疾病的天然的力量。在这个阶段，各种疾病开始侵袭受到艾滋病病毒感染的人体，这个人就被称为患了艾滋病。
什么是艾滋病病毒？
艾滋病病毒（人类免疫缺陷病毒），英文简称HIV，是一种能够导致艾滋病（获得性免疫缺陷综合征）的病毒，这是一种由于人体免疫力低下而感染各种疾病时的状况。艾滋病病毒本身不是一种疾病而且并不立即导致艾滋病。一位艾滋病病毒感染者在发展成为艾滋病病人之前可以健康地生活很多年。
（以上信息来源中国红丝带网）
HIV self-testing on the Frequently Asked Questions
At 16:20 on August 19, 2009
1. I would like to ask how the accuracy of dipstick testing?
This issue is on paper or false positive and false negative problem, namely the issue of sensitivity and specificity, according to the national laboratory on blood samples of 12,038 copies of the application of the general population, the test strip detection of all the negative, at the same time with the reference ELISA Detection Kit found three cases of false positive (confirmed test is negative).
At the same time, we have retained in this laboratory has made it clear the 10 of HIV-positive serum, were determined by paper, all positive results. Fully mechanized, the paper shows that the sensitivity and specificity, and of course we can not say 100% because it is possible that our experiment is also not big enough sample size. From the State Drug Administration Bureau is the sensitivity of the data provided by 99.73%, specificity 98.81% (the latest official data), on any kind of testing method, it is too bad.
Note: The blood test strip in detection can be found in the conventional environment, the experiment does not require a special environment, and does not require any special reagents other
2. HIV test strip work?
The dipstick is GICA detection technology developed by a new generation of reagents, can be detected in serum or plasma specimens of HIV-1 / 2 specific antibodies. The entire operation time only 15 minutes, is simple, rapid, accurate, and bring their own quality control, without any additional reagents. Applicable to clinical examination, screening and other non-remunerated blood donation site. The principle is:
Nitrocellulose membrane in the detection of DNA-coated areas of the HIV - 1 +2 antigen coated in the control area of anti-HIV antigen monoclonal antibodies. Testing samples of anti-HIV antibody and colloidal gold marker gene recombination of HIV - 1 +2 antigen formation of Ag-Au complex, due to the role of chromatography, membrane complex along with the mobile, can be coated with recombinant HIV - -1 +2 formation of double antigen sandwich antigen immune complexes. If the positive sample, then in the control zone detection zone and the formation of the lectin a red line, such as negative samples, only in the control zone to form a red line.
3. Positive (+) What is the significance of the results?
Two red lines appear on paper that HIV-positive blood. Blood samples that were highly suspected to be HIV infected, to the final confirmation, we need to do Western-Blot test, of course, the pilot needs the provincial level or above to complete HIV testing laboratories and inspection reports issued, by any other medical units HIV testing done only with the detection of this paper has the same meaning. If you detect a positive result, please contact a timely manner with the moderator, for confirmation tests. You do not have to worry, however, the detection sensitivity and specificity is already quite high, the basic test will not be confirmed because of rounding. In fact, almost all use of this test is sufficient, because the reliability of the results of its negative enough to make you happy, we turn to the following.
4. Negative (-) What is the significance of the results?
Only one paper on the red line (control line), indicating that the HIV antibody-negative blood. Blood samples that have not been infected with HIV, the subjects can be at ease. However, there is little need to show that in the "window period" (high-risk behavior within 3 months after) was detected within the negative results may not be correct, because during this period, the body of HIV infection has not generate enough to be detected antibody. Therefore, the "window period" after the best 6 months after the detection of the negative results obtained were completely at ease before we can make it.
5. If the paper how the red line does not appear to do?
That the test failed. The possible reasons are: failure to operate the operational procedures, or inherent in the quality of paper (very few), please take another test strip cards.
6. Detection of whole blood and serum testing are they different?
On whole blood and serum testing, as long as time does not determine the outcome of more than 30 minutes, the two non-discriminatory. Why? Because the samples on cellulose acetate membrane in the process of chromatography, blood in the proliferation rate of different components, when the HIV antibody in serum reached the detection zone, and significant red zone, the plasma hemoglobin has not yet reached the detection area, at this time (30 minutes) to determine the outcome without any problems. More than 30 minutes, with the red hemoglobin itself has reached the detection zone, for non-professionals, this will bring about a little confusing to determine the outcome, but in fact it is not difficult to identify, as long as the application of one paper, they will know that the real positive (red) horizontal line is detected, the red hemoglobin produced relatively chaotic confusion, but also vertical, extending upward from the bottom. However, the benefits of whole blood testing is still quite obvious, as long as 1-2 drops of blood, very convenient. Of hospitals or epidemic prevention station, it can be combined with other items of blood tests, using serum, you do not need to repeat the blood. Of course, the paper prices of 96 of the ELISA reagents 96 more expensive, this is not a large number of medical and health units of the reasons for using it.
7. Detection of infectious blood test strip it?
Recently, there have been some of my friends to call the Post tells us that the past few days on a private Web site said: "The blood test strip containing HIV, is contagious," asked whether we like this. We feel that a very funny, a bit of medical knowledge knows that various types of paper in the packaging process before going to work together, and that is "sterilization experiment", not to mention in the paper do not contain HIV, how contagious, if we do not understand, you think so you will understand: if a paper is done by detection of HIV and AIDS at the same time we all know that after leaving the body a few hours to several days will die, then all of us to think, in the paper on the "virus" is also how survive? This is also how the next experiment? daunted "virus" before leaving the human body can survive? Otherwise, how can it contagious? So we all just need to think about some of the individual on up the paper with some blood tests infectious, is the consumer, the community extremely irresponsible, as an experiment into why doctors were wearing gloves, in fact, this is very simple, because it is contact with blood products (doctors access to all blood products are wearing protective gloves, but to do their own testing is not necessary), the main blood products to prevent cross-infection measures taken by our testing has repeatedly stressed that we must not do more than cross-use of blood testing tool, not some people say paper is contagious!
8. With regard to the use of diluent
Individuals in the use of dipstick testing to do, if the smooth conduct of testing, do not join the diluent, if not exceeding the best plus 1-2 drops, diluted if more than two drops of fluid, your test results can not be guaranteed, it There are a lot of false negative results may be, for this reason is very simple, when the blood contains HIV antibodies, when the Baptist when to T, T Department paper on the special material of fearful reaction occurred with the antibody, which is shown T-line, if you joined the diluted solution will significantly reduce the concentration of antibodies, thereby increasing the chance of false-negative. So a friend recommended that the process of doing testing, if the testing should not proceed smoothly by adding dilution, that is, to join must not exceed Second, drop, drop it is best, otherwise, would significantly reduce the sensitivity of detection, resulting in a large number of false-negative, and that a large number of non-professionals to encourage to join in the testing process is the dilution of science on society of consumers is extremely irresponsible behavior, no matter what is the purpose of their departure, which should be commended for the broad masses of people are condemned.
9. And ELISA methods, the advantages and disadvantages of testing paper?
Both sensitivity and specificity is almost no difference, ELISA used for mass screening of populations, each one can detect an enzyme-linked plate 92 samples, the single price on a number of relatively inexpensive. However, if a piece of board only for the detection of less than 10 people, the prices are too expensive. And many steps must be completed by professionals. Application of paper to facilitate detection and without the complexity of the steps, individuals can independently determine the method is simple, only slightly more expensive price.
10. Saliva can detect it?
So far, no application of saliva samples as a detection test strip.
11. AIDS can be detected by urine it?
So far, companies from the United States and the United States卡普里特Cambridge biotechnology company to produce urine HIV test paper, the same time, he is also capable of producing the world's only manufacturer of the paper, is the shortage of paper in the test by the HIV1 virus infection has been quoted in a higher accuracy of the HIV2 virus infection caused by a low sensitivity test strip can not be very accurate to detect whether the HIV2 virus infection and its subtypes, so the relative accuracy of the detection of the current General paper to lower blood tests, urine HIV test strip at the same time the current high false-positive, the country has not yet formally recommended.
12. AIDS testing urine test strip of paper with the blood What's the difference?
AIDS blood urine dipstick test paper and the main difference is: more accurate urine test strip can be detected by the HIV1 virus infection have been cited, not very accurate to detect whether the type and subtype were HIV2 virus infection, its Detection of virus infection HIV2 accuracy is not high, but its greatest feature is easy to operate, no blood; blood test strip as a result of production technology has reached a mature state, HIV1, HIV2 virus-induced infections, the paper can be accurately detected , and its accuracy as high as 99.73%, the lack of points is the need for blood in the blood during the cross if people use the same collection tools, easy to cause cross-infection, so do blood tests in the blood, the blood can not cross-mix of tools, must be done to each one separately so that. It is precisely because of the accuracy of blood test strip is almost as high as 100%, so by all countries to promote the use of widely! two paper exactly the same as the operation is different from the sample.
13. With the results of dipstick testing, I can rest assured that you
A letter from some of my friends often ask us, by dipstick testing and the results can not be assured that we address this issue was also done in front of some note, by the Ministry of Health HIV Prevention and Control Center, the People's Liberation Army HIV confirmation laboratory, in Beijing Ditan Hospital authoritative testing organizations such as the six sampling 3327 blood samples were verified, comprehensive blood test strip in detection accuracy rate of 99.8 percent more than the majority of the local epidemic prevention station hospitals and the wider use of AIDS antibody testing as a preliminary paper of the rapid diagnostic testing methods, test results can be reassuring.
14. The accuracy of HIV antibody testing may have up to 100%?
This is an all the more concern, fear of AIDS is often some friends to come to the consultation, but the experts tell you to any antibody to detect through the experiment, its accuracy is not possible to reach 100%, a bit of medical knowledge Road through the antibodies are detected in any of the experiments are not there to avoid false-positive cases (HIV testing is no exception of course), that is to say when you have the HIV antibody in vivo from the medical point of view does not mean that you are infected the HIV virus, if someone told you that the HIV antibody test as high as 100% accurate, it certainly is a lie, but be sure your body when HIV antibody test was negative when the (outside window), affirmed 100 % have not been infected with HIV virus, which is why AIDS should be divided into initial testing (antibody detection), diagnosis (etiology) two-step process. Judging from the current market, HIV detection test strip is much better than imports, domestically produced, as a result of urine test strips can not be very accurate to detect whether the infection and its subtypes HIV2 virus, its detection accuracy will be relatively low number of blood test strip.
People infected with AIDS through the following ways:
A. Unprotected sex
If an HIV-infected persons and sex without using condoms, he may be infected with AIDS. Sex, including vaginal intercourse and anal intercourse.
Theoretically, no condoms (male) or as braces, female condoms or plastic film shelter material (female) will be transmitted to perform oral sex when the AIDS and other sexually transmitted diseases.
B. Unsafe blood, shared use of syringes and sterilization of medical equipment correctly
If a person infected with AIDS by sharing needles or syringes for intravenous drug use, blood or any act of piercing the skin of the activities, he / she may be infected. For piercing or tattoo number of the tool will be the risk of transmission of AIDS.
The importation of blood infected with HIV will be infected with AIDS.
Such as syringes and scalpels, such as surgical equipment, and even used for intravenous injection and blood transmission equipment without proper sterilization, may be the spread of AIDS.
C. Mother to child transmission:
If the mother is infected, it may be through pregnancy, childbirth and lactation-to-child transmission of the process.
★ Gender and AIDS: from the spread of AIDS, the AIDS-susceptible women, on the one hand, physiological characteristics, on the other hand, due to gender inequalities.
Vis-à-vis gender is a concept of sex is due to social, economic and cultural impact of the day after the formation of the social differences between men and women and power relations, and the resulting characteristics of social groups of male and female roles, activities, responsibility expectations and norms.
Gender inequalities make women more susceptible AIDS, specifically manifested in: the status of women in the family of inequality, girls can not own the right to education, women have no economic autonomy of women, such as cultural constraints, resulting in women in the selective and sex and subject to many restrictions, in a timely manner after infection can not be found or could not be found in time after treatment.
What is AIDS?
AIDS called the Acquired Immune Deficiency Syndrome, the English referred to as AIDS, who for AIDS. AIDS is infected with HIV in HIV-induced immune after the lack of which led to the adverse health status of the disease. HIV to resist various diseases by damaging the immune system to attack the human body.
After a period, the lower the immune system, the body loses its natural resistance to the forces of disease. At this stage, the beginning of the invasion of various diseases of HIV infection by the human body, this person will be referred to as suffering from AIDS.
What is HIV?
HIV (human immunodeficiency virus), the English referred to as HIV, is a can lead to AIDS (Acquired Immune Deficiency Syndrome) virus, which is a low immune system due to the human body and at the time of infection status of various diseases. HIV is not a disease but does not immediately lead to AIDS. An HIV-infected persons in the development of AIDS patients as a healthy way of life before many years.
(The above source of information for the Chinese Red Ribbon Network)
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