What really happens during and after unprotected sex with an infected partner!

I chose to begin this series with this topic because I feel we need to move step by step. We need to trace the life cycle of the virus sequentially so that we can be able to understand what really happens when one gets infected and later on be able to appreciate the current targets of treatment. Thus, first things first: SEX!

When Jacob Zuma took a vigorous bath after having sex with an HIV positive woman, did it or didn’t it help? I hope by the end of this article we would have been able to at least make a decision on this method of prevention.

Before we jump straight into the scientific pool, there are a few points that I want to make. Firstly, I want to define a virus. A virus is a very small particle that cannot be seen by a naked eye. A virus is not a bacteria however they both are not visible to the naked eye although it is very possible for us to see bacteria (like cholera bacteria or Tuberculosis bacteria) using a simple microscope found in hospitals. Most viruses are more than a thousand times smaller as compared to bacteria thus we need highly specialized microscopes called electron microscopes to see them (in Zimbabwe there are only two such instruments).

Secondly, unlike bacteria, viruses are non-living things. They do not use energy for respiration, they cannot multiply on their own, and they cannot manufacture anything for themselves. So how do they survive? Ha ha ha, they are not alive; when a virus is outside a body it is as useless as the soil. How do they multiply? Here is the tricky part and I want you to understand because this forms the backbone of virology. Once you understand this you just become a virologist!

A human cell has at its core, genetic material that has got information which makes us different from each other. It is this genetic material that makes me different from Usain Bolt or Robert Mugabe and it is called DNA. This DNA is also responsible for storing the information about which proteins to make. Now, when HIV comes in contact with a human cell, it can be sucked into the cell, and through complicated mechanisms which we will talk about later, be able to attach its viral matter to the cell’s genetic matter. At that point, the cell will have information about human DNA and viral DNA. The cell is unable to differentiate between the information contained by this compound genetic matter thus it just starts to manufacture proteins regardless of whether they are for body use or they are viral proteins. That is how HIV abuses our bodies to its advantage!

A question that I want to ask before we begin is; why is it that shaking hands with someone who is HIV positive does not spread the virus? Or why is it that if one inserts his finger into the vagina he does not get HIV yet if one inserts his penis there is risk of transmission?

The answer lies here. The skin is made up of keratinised, stratified squamous epithelium, what this simply means is that, the cells that make up the skin are layered on top of each other like bricks, then they are cemented together by a chemical that our bodies produce known as keratin. This makes the skin hard to corrode. So even if one puts his finger in the dip-tank of HIV he will not be infected unless it’s bruised or has a cut.
The penis has got a shaft, the inner and outer surface of the foreskin and a urethral duct which passes urine. The skin that covers the shaft is as hard as that of the whole body and therefore protects against HIV infection. What we need to understand is that, the inner mucosal surface of the foreskin is not as hard as the outer skin. This part is heavily populated by cells that are called Langerhans’ cells.
During sex, the foreskin is usually pulled back so that the entire soft tissue is exposed to the walls of the vagina. The purpose of the Langerhans’s cells is to defend the body against any infective agents that may enter through the penile route. So, once there is slight friction, the soft surface is exposed and if it so happens that the woman is HIV positive and is secreting viral particles in her fluids there emerges a chance that HIV may attach to these cells.

These Langerhans’ cells have got a special receptor called CCR-5 which has got a great affinity for the HIV proteins. Once, a CCR-5 receptor attaches to HIV, the virus vomits its genetic matter into the cell. The Langerhans’ cells, as good as it is at its job of capturing tresspassers and carrying them to the guillotine; will then carry the viral matter inside itself whilst starting to make viral proteins on its own. The duty of the Langerhans’ cells is to present the HIV to the white blood cells that are supposed to be able to once and for all deal with this threat. Unfortunately, Langerhans will present viral matter to the CD4+ white blood cells which also suck the virus and become infected too!

The vaginal tract is also the same as the foreskin in terms of concentration of the Langerhans’ cells. What should be noted is that semen in infected people contains both free viral particles and more than a million white blood cells some of which would be infected. So there is possibility that when a man ejaculates into a woman because of greater contact time the woman might be at a greater risk than a man. Scientifically however, it has not been conclusively proved to be so as the results vary geographically with Africa showing approximately equal per-act probability of infection between men and women.

So, can Jacob Zuma’s method be trusted? Well, this one is tricky in that like I said the virus is not a living thing and cannot be killed by a detergent so don’t think Lux can kill HIV! Secondly, even if one washes his hands thoroughly with water, bacteria (which is bigger than HIV) will always be present, so how confident are we that thorough rinsing can remove all the millions of particles attachéd to your penis? Finally, it has been proved also that HIV infection is dependent on the amount of HIV (size of inoculum) that one is exposed to; so maybe by bathing one can reduce the number of particles attached to the mucosa but HEY DO THIS AT YOUR OWN RISK!

Having learnt the above, it does not need a virologist to realize that ABSTINENCE remains the best form of protection, followed by Single Trusted and Tested Sexual Partner then Consistent and Correct use of the CONDOM!I love you all and hope you enjoyed get ready for the next topic: Oral Sex: Who can eat HIV and survive!