Hepatitis C, part two
Following on from last month's article on the government's hepatitis C strategy, Henry Grahame-Smith examines the data on the risk of contracting hepatitis C
 Illustration: John Clarkson |
Over the past few months I have interviewed five HIV positive gay men who have been diagnosed with hepatitis C during the past couple of years. All of them had questions about transmission either related to how they contracted it or to the risks that they may inadvertently be exposing friends, partners or family to.
To illustrate this I have asked Mike, who would rather remain anonymous, to tell his story.
"About a year ago, during a routine clinic visit, my doctor said that the results of a Liver function test were abnormal. He said that he would do them again and also run some tests to check for hepatitis A, B and C. "About a year ago, during a routine clinic visit, my doctor said that the results of a Liver function test were abnormal. He said that he would do them again and also run some tests to check for hepatitis A, B and C. I wasn't worried - I've been taking anti-HIV treatment for about five years now and my liver enzymes had fluctuated in the past. I'd had hepatitis A while I was at university and had been vaccinated against hepatitis B. A week or so later I got a telephone message from my doctor asking me to call him. This was unusual but I didn't put two and two together at the time. When I called him from work the next day I was gobsmacked when he told me that I had hepatitis C. When I moved to London in 1999 the clinic I went to tested me for hepatitis C and it was negative. The doctor said that the really high liver enzymes that had sparked of this investigation probably indicated that I was just seroconverting, and that the infection had occurred within the last three months or so. For one reason and another I was not going to be able to see my doctor till six weeks later. I had loads of questions so decided to trawl the internet to try and get some answers. It was pretty easy to find the answers to my questions about the sorts of test that the clinic would do and what they would mean, various treatment options, whether to start treatment now or wait, and whether the hepatitis C would affect my HIV and its treatments. But it was much harder to find information that made sense to me when I wanted answers about how I got it. There was loads of stuff about how hepatitis C is transmitted through blood-to-blood contact. Activities such as sharing drug injection equipment or in the past having a blood transfusion, a transplant or injecting blood products for illnesses such as haemophilia. This didn't apply to me since I've never injected drugs or had a blood transfusion and I don't have haemophilia. Most of the websites I started looking at either said that sexual transmission was either a negligible risk or at least rare. However, some did say that people with hepatitis C should use condoms during sex. This didn't really make sense to me either. I can't say that I have always been an 'angel' when it comes to safer sex. There was a time that I really enjoyed barebacking with other positive guys. However, I got a wake up call in 1998 when I was diagnosed with syphilis. The 17 days of daily antibiotic injections made me decide to do my utmost go back to practising safer sex. I enjoy the slightly rougher side of sex but the last time I didn't use a condom was during a drunken episode about three years ago. This certainly doesn't correlate with the timescale of contracting hepatitis C some time between November 2001 and March 2002. This has really worried me. Since the diagnosis I have noticed I often make excuses if someone tries to pick me up in a club or bar and I'm even reluctant to go out to my old haunts on the gay scene. It has been about 10 years since I felt reluctant to talk to my lovers about my HIV status, whether it was likely to be a 'quicky', a one night stand or longer. Initially, I thought this experience of HIV would have prepared me for the conversations about my hep c status. However, I find that I cannot raise the issue of hep C with the same self-assurance as I do HIV. Most gay men in this country don't know a lot about hepatitis C and I don't want to have to do too much education when I would rather be having fun. I've not been completely 'monk'-like but questions about whether I am putting the other guy at risk do go through my mind. During the last year there has been an increasing amount of information about sexual transmission of hep C especially among gay men. Could you help me make sense of it so I can put it into practice and stop worrying so much?" |
Hepatitis
C: a blood-borne virusIf you have hepatitis C, the body fluid with the highest concentration of the virus will be your blood. The hepatitis C virus (HCV) is classified as a blood-borne virus since it is mainly transmitted through blood-to-blood contact.
The blood from someone with HCV needs to find its way into your body. Intact, unbroken skin will prevent this from happening. However, it can get in through open wounds, cuts, breaks, tears in the skin and punctures made by needles. Theoretically it may be possible for HCV in the blood to pass through delicate mucous membranes such as those in the vagina and cervix, rectum and nose. The risk greatly increases if there are breaks, abrasions or tears.
Before
HCV was isolated in 1989 the condition was often referred to as post-transfusion
hepatitis because there were people who, after receiving a blood transfusion,
experienced inflammation of the liver (hepatitis) and did not have hepatitis A,
hepatitis B, or any other explanation for their illness.
Blood tests for HCV were developed in 1989/90 and introduced as a procedure for screening donated blood by the National Blood Service in 1991.
The risk of contracting hepatitis C from blood products, used by people with haemophilia, was made safe by the 1986 introduction of sterilisation in response to the risk of HIV.
This means that in economically rich countries, the vast majority of new infections happen as a result of people sharing drug injection equipment.
The viral load of hepatitis C in your blood tends to be much higher than HIV viral load - often several millions. So, if you are injecting drugs you should be aware that the precautions, which are adequate to prevent HIV transmission, might not necessarily prevent you contracting or passing on the hepatitis C virus (HCV).
There is evidence that sharing tourniquets, spoons and filters, as well as the actual needle and syringe can often be responsible for transmission. Your needle exchange scheme should be able to give you more information about how to reduce the risk of HCV transmission or tell you of a local agency that can help.
In this country around 90% of HCV cases reported to the Public Health Laboratory Service (PHLS), in which risk factors have been reported, are related to current or previous injection drug use.
Sexual
transmission: how does it happen?In the US, data from the Centers for Disease Control shows that since 1990, there has been a gradual but significant rise in the percentage of acute cases of HCV with sexual transmission as the risk factor.
Although HCV can sometimes be detected in body fluids other than blood, it is in such low concentrations that most scientists think that it cannot result in transmission. Though, since HCV has been detected in menstrual blood and the genital tract it is theoretically possible (see below).
In November 2002, Hepatology journal published an article by NA Terrault a scientist from the University of California. It was a review of the studies which looked at sexual activity as a risk factor for the transmission of HCV in serodiscordant couples, where one partner has hepatitis C and the other does not.
For heterosexual, serodiscordant monogamous couples the risk of transmission is lower (0% to 0.6% per year) compared with those with multiple partners or those at risk for sexually transmitted diseases (0.4% to 1.8% per year).
Another study has found that the risk of contracting HCV to be threefold higher for a woman in a heterosexual discordant couple compared to a man.
Recent studies also show that having both HCV and HIV increases the risk of transmitting HCV in both heterosexuals and gay men. The concentration of HCV tends to be higher in the blood of people co-infected with HIV than among those who aren't. And recent studies show that men with both a high HCV viral load and HIV co-infection are quite likely (about one case in four) to have detectable HCV in their semen (see www.uk.gay.com/headlines/4038 for the latest news on this).
Blood is an important issue to raise at this point. Wearing a condom is going to dramatically reduce the risk of HCV transmission even if you have HIV. However, we all need to be blood aware during sex.
While talking to Mike about the details of his sexual encounters I began to realise there was a risk that he hadn't thought of.
The amount of blood that needs to get into your system for transmission to occur is far less for HCV than HIV. Also we do not know how long HCV can last outside the body. There is research that shows HCV can survive in dried blood for at least three months. And further research needs to be done to determine the best ways to sterilise equipment.
Anything with blood on it, that goes into your body, is a risk. It became apparent that Mike was not aware of the risks of a shared bottle or tub of lube.
If one of you has got a bit of blood on your hands, which could have come from handling a sex toy or even more easily from fisting, then this blood could easily be transferred to the bottle of lube or into the tub you are using. Using it can then lead to a path where the infected blood gets into the body of the HCV negative person through a tear or abrasion of the vagina or the rectum.
Perhaps we all need to be a little more careful, and try to use some of the techniques from a few years back that I think may have become a little less common.
Have your own bottle or tub of lube, have your own towel to wipe your hands and anywhere else and try to keep track of where fingers and others objects have been and are going.
There are other ways that transmission can occur. A small number of people have contracted HCV through getting a tattoo where the needle or the ink was not sterile. Ear or body piercing and acupuncture needles are also a risk if proper procedures are not used to stop the risk of infection. Transmission has also occurred where family members have shared razors or toothbrushes.
Sharing a rolled up note to snort cocaine is a theoretical risk. A large prevalence study in the states showed that the incidence of HCV was much higher in those people who had a history of snorting cocaine compared with those that didn't. So to be on the safe side I would suggest using your own note!
Next month: the latest on treatment for hepatitis C
