艾滋病毒传播原理（译自英国某同志健康网）

杰生

HIV is usually transmitted sexually, although it can also be transmitted through sharing needles or from mother to child. For HIV transmission to occur as a result of sex between men, the following needs to be the case:

• One of the men must have HIV (the section Is he likely to be HIV-positive? gives more detailed information about this).
• The sex must involve body fluids that contain sufficient quantities of HIV.
• These body fluids must get into the bloodstream of the negative man (the section How risky is...? has details about the kinds of sex that facilitate HIV transmission).
  

HIV经常经由性接触传播。它也可通过公用针头传播或由母亲传给婴儿。以下情形是可以经由男性性行为传播HIV的主要途径：
1. 一方是HIV阳性。
2. 性行为中必须有包含足量HIV的体液。
3. 体液必须进入HIV阴性一方的血流之中。

Body fluids （体液）For HIV transmission to occur, HIV-infected body fluids have to pass into the bloodstream of an uninfected person. While HIV can be found in many different body fluids of a person with HIV, only some body fluids contain a sufficient quantity of the virus to enable HIV infection to occur. These body fluids are:

• Blood
• Cum and pre-cum
• Discharge from STIs (such as gonorrhoea)
• Anal mucus
  

Anal mucus is a naturally occurring fluid that lines the arse. Its main function in the body is to lubricate your shit as it passes. Research indicates that anal mucus is the body fluid with the highest concentration of HIV.1
You cannot become infected with HIV through exposure to piss or saliva.
只有当阳性一方的足量体液进入阴性一方的血液中，才可能发生感染。虽然HIV病毒可以在各种不同类型的体液中发现，但只有某些体液中才含有足够引发感染的病毒量，这些体液是：
1. 血液
2. 精液和前列腺液
3. 受到性病（如淋病）引发所分泌的毒液
4. 肝门粘液
肛门粘液一般顺着屁股流出，其功能是在排便时帮助润滑粪便。研究表明，肛门粘液中的HIV病毒载量是最高的。
How HIV enters the bloodstream （HIV如何进入血流）There are two ways for HIV to get into the blood of an uninfected person:

• Directly into the bloodstream through damaged skin, injecting equipment or invasive surgical procedures.
• Through mucous membranes.
  

hiv进入未感染者体内的途径有两条：
1. 直接经由注射或损伤性外科手术进入体内，或者经由破损皮肤进入血流。
2. 通过黏膜。
Mucous membranes are thin tissues which protect openings in the human body. There are many mucous membranes in or on a person. They occur in places like the mouth, inside the eyelids, in the stomach and along the digestive tract. HIV can travel through the surface of a mucous membrane, enter the tiny blood vessels inside and attach itself to the mucous membrane.
However, the mucous membranes that are most commonly involved in HIV transmission are in:

• The arse
• The foreskin and head of the penis
• The urethra (the tube you piss through)
• The mouth and throat
  

黏膜是一层很薄的保护性组织，在人体内部或体表有很多黏膜。例如在口腔内，眼睑内侧，胃脏和消化腺。HIV可以直接穿透黏膜组织表面并进入黏膜组织内部的毛细血管。不过，与HIV传播具有直接联系的黏膜组织主要位于四处，它们是：
1. 肛门
2. 阴茎的包皮和龟头
3. 尿道
4. 口腔和咽喉
With the exception of the mouth and throat, none of the mucous membranes need to be damaged to provide an effective route for HIV transmission to occur. However, damage to the mucous membranes, like a sore or a cut, does make transmission more likely. Of the four mucous membranes that can allow HIV to enter the bloodstream, the mucous membrane in the arse provides the most effective route for HIV transmission. This is because the mucous membrane in the arse is designed to absorb liquids directly into the bloodstream. It is therefore extremely efficient at absorbing HIV. The mucous membrane on the head of the penis of circumcised men hardens. This provides some protection when it is exposed to HIV-infected fluids. However, it is still a possible route of HIV transmission.
在黏膜组织中，除口腔和咽喉外，其它所有三种黏膜即使没有破损，也可能被HIV穿透。当然，黏膜破损（例如一个溃疡或割伤）会增加HIV进入血流的机会。在四种黏膜中，肛门黏膜最容易被HIV穿透，这是因为肛门黏膜具有把液体吸收进入血液的功能，所以，它吸收HIV入血的效率也非常高。作过包皮手术的男性其龟头较为坚固，因此具有一定的抵御hiv能力。但即便如此，龟头依然是hiv进入血流的一个渠道。
What makes transmission likely? （是什么在增加感染的可能性？）Some types of sex between men make HIV transmission more likely. The situation that is most likely to result in HIV transmission is:
A man with HIV (whether or not he has been diagnosed) fucking an HIV-negative man without using a condom and cumming inside him.
This situation is the most likely to facilitate HIV infection because:

• A positive man fucking a negative man without a condom means that the negative man is exposed to HIV.
• A positive man's cum is a body fluid that will usually have a sufficient quantity of HIV in it to infect the negative man.
• The mucous membrane in the negative man's arse provides one of the most effective and efficient routes for HIV to enter the bloodstream.
  

男男性行为的某些类型使得hiv传播更为便捷。最容易引发hiv传播的情形是：
一个hiv阳性的男性无套插入一个hiv阴性的男性肛门并且在体内射精。
这个情形之所以更容易传播hiv是由于：
1. 阳性插入方插入阴性**方意味着后者直接接触了的hiv。
2. 阳性插入方在体内射精意味着被插入方接触了足够引起感染的病毒量。
3. 被插入方的肛门黏膜是hiv进入血流的最有效和最佳途径。

sarchiel

危险似乎比想象的要高啊

我建议

英国的比美国的恐怖，病毒可以穿过完好的粘膜呵呵。