Vaccines for Herpes Infections
by Dr. H., Medical Director www.herpes.org
Probably 50 million Americans have GHI (genital herpes infections). This ranks GHI as being one of the most prevalent medical conditions in the country. Countless millions more elsewhere in the world suffer from this problem. Will there ever emerge a vaccine that will “cure” GHI? Will there ever emerge a vaccine that will prevent transmission of GHI? This article will start out simple and become more complicated as you read on. Further reading will add greater depth to your reference information, but you need only read a few paragraphs to get the gist.
Vaccines for GHI have been being produced for at least twenty years, especially in Europe. Numerous centers in Italy, England, Bulgaria, and elsewhere have produced many different versions of Herpes Simplex Type 2 vaccines, many of which have been submitted to rigorous human testing. These vaccines have been used BOTH for prevention of transmission of GHI as well as for treatment of patients with GHI. The results of almost all of this information, when looking at the literature honestly, is that the vaccines may offer a very slight benefit for preventing transmission and treating infection. But, sadly, only a little bit.
Specifically, Mastrolorenzo’s previous work in Florence used multiple injections of vaccine over many weeks to produce a modest reduction in outbreak frequency among infected women. It did not prevent recurrences. Vaccine developed in England gave initially high marks for reducing recurrences and preventing transmission. American study of the same vaccine did not reveal the same findings. Both vaccines are available for those interested, but one might have to travel to that country to take it. The Bottom Line: There MAY be some benefit from these vaccines to reducing recurrence frequency. They do NOT eradicate the virus from the body, however, and do not prevent recurrences.
Numerous articles have suggested that these European vaccines also reduce transmission of GHI to non-infected partners. Some validity may exist to these claims. Read this carefully, though, before you consider booking a flight: It is difficult to separate out from the effect of the vaccine the other effect of “patient counseling”, that is, being “smart” about managing GHI. Smart partners work at not transmitting the illness. Partners who go to a Herpes clinic and take vaccines are smarter for the experience and likely more careful. That alone would decrease the transmission rate, as it should.
A vaccine uses a product of the body’s immune system to kill virus particles, either antibody (liquid protein floating around in the blood and body fluid) which is directly targeted toward proteins on the virus, OR lymphocytes (white blood cells that are turned on by the immune system to fight infection) that are targeted toward some of the same proteins on the virus. Different diseases are prevented by different parts of the immune system. In the case of GHI, it is not certain what part(s) of the immune system is/are necessary to prevent infection from being transmitted. Also, in the case of GHI, it is not yet known if the body’s immune system CAN completely prevent disease from being transmitted or recurrences from happening.
Herpes virus infects the nerve cells, getting into the cells directly inside the skin and then traveling up the dendrites and nerves to the nerve cells by the spinal cord. There the viruses bond with the human DNA inside the nerve cell and form a permanent home, producing viral particles from time to time. Prevention of transmission would require that SOME part of the immune system be able to kill (or render inactive) the virus the instant it appears at an entry site for a non-infected partner during the sex act, before the virus can be inserted into the nerve tissue. Whether or not this can even be accomplished is uncertain at this time and represents one of the forefronts of research into GHI vaccines.
What IS known is that the many Herpes vaccines that have been produced, almost without exception, generate very strong immune responses in the animals and humans to which they are given. Animals given many of these vaccines and then subsequently “challenged” with Herpes virus very frequently demonstrate dramatically reduced severity of infections and reduced outbreak recurrence rate. However: No study has convincingly shown complete protection from infection after a vaccine nor the complete elimination of outbreaks.
Interestingly, numerous studies have indicated a dramatic presence of anti-Herpes antibody in the vaginal fluids of vaccinated animals. This fact will likely be one of the key players in the future of controlling infections for females.
This is a very exciting time in the history of vaccine production. An absolute avalanche of DNA vaccines are being produced for the first time in history for many various diseases. These are vaccines in which actual DNA is injected into animal or human bodies. This DNA is carefully manufactured to then go into the cells into which it is injected and begin producing proteins that stimulate immune responses by the body. For example, the injected DNA might cause the body to produce the “G antigen” of Herpes Simplex Type 2. This antigen (which is only a tiny, tiny portion of the virus membrane and does NOT cause any sort of infection) stimulates an intense production of antibody against the “G antigen” of HSV2. So, if HSV2 shows up anywhere in the body, presumably the antibody produced by the body will knock out the HSV2. Right?
Well, the answer isn’t known yet. The DNA vaccine efforts for GHI are only just now being explored and are probably 3 or 4 years away from substantial information being generated. Will these vaccines (1) prevent recurrences, and (2) prevent transmission to non-infected partners? No one knows. Is it likely? Possibly.
A scientific paper published in early 1999 studying Herpes infections in mice found that a new DNA vaccine causing production of a certain herpes virus protein modified with bupivicaine in fact caused perhaps a 99% reduction in the ability to infect mice with “Herpes challenges” in the vaginas of the mice. This is, perhaps, the most encouraging evidence to date that in the not too distant future, a vaccine will be produced against genital herpes infections that will at least dramatically reduce the transmission of Herpes, if not virtually eliminate it. However, human test results have not as yet achieved the same results.
American drug and research companies are heavily invested in Herpes research. If a vaccine could have been produced by now that was safe and reliable, it would have been. Numerous American research trials have been carried out on Herpes vaccines. None have consistently given protection OR treatment. American investors understand just how huge this product would be. With 50 million sufferers and all of their partners wanting the vaccine at, say, $100 a shot, one can imagine many tens of billions of dollars in available drug sales to the company that can pull it off. It is not from want of trying that a vaccine that works is not available in America. It is because the answer is not yet available.
What has to happen before a safe and reliable vaccine against GHI, both recurrences and primary infection, emerges?
- We have to know why recurrences occur. What causes the nerve cell machinery to sometimes produce viral particles and sometimes not?
- Can the body turn off the reproduction of viral particles from the nuclei of nerve cells? This is unknown. Apparently it often does, but then, why does a stressful episode, or nothing at all for that matter, abruptly turn it back on?
- Can or does the immune system get involved with turning off the production of viral particles? No one knows.
- Does a vaccine that “treats” GHI cause the body to kill the viral particles as they emerge? Is that the same thing as “producing an antibody against oneself”, as is what happens in the setting of Lupus, Rheumatoid arthritis, Hashimoto’s Thyroiditis, and other so-called “autoimmune diseases”? Does that mean that there may be a risk of inducing “autoimmune disease” by the use of a Herpes vaccine? No one knows.
- What portions of the immune systems could protect against a “direct inoculation” of virus into the nerve cells of the pelvis (or of the mouth, for that matter)? Antibody? Lymphocytes? Both? Something else that we don’t know about?
- In a similar note, what portions of the immune system are “required” to “control” outbreaks, if they can even be controlled? It would make sense that SOMETHING about the immune system can be stimulated to control outbreaks, given the fact that most people with herpes infections have no symptoms. It is the minority of infected people that actually have symptoms. What can we stimulate, in the immune system of an infected person, to cause that same kind of “control” of viral replication to be exerted? We just don’t yet know.
- Is it possible that the immune system might not be able to prevent virus entry but rather would only be able to “limit” the size of the infection once it occurs? Evidence with certain current vaccine efforts suggest this.
It would be important to comment at this point regarding new vaccine research that has emerged in the last several months. SmithKline Beecham recently released the results of their study regarding a new vaccine attempt for genital herpes. Sadly, the results indicate that any benefit from the vaccine seems to be limited to female patients who have never had a type 1 herpes simplex infection AND who do not have genital herpes currently. This seems to mean that the vaccine only offers partial protection from acquiring type 2 genital herpes.
Interestingly, this MAY also mean that this vaccine is only able to achieve protection from acquiring genital herpes that is essentially identical to that which is gained from having a previous type 1 infection. If this seems confusing, just remember that a previous type 1 infection does offer a modest protection from acquiring a type 2 infection later, and apparently the vaccine is able to duplicate this protection in the patient that does not already have a pre-existing type 1 infection. In the 2002, the NIH began studying this vaccine in females who do not have antibody against either virus, to determine if significant protection is offered to these individuals. See the May-June 2002 Newsletter for more on this development.
It is of interest to note that the DISC vaccine that was under development by Cantab Pharmaceuticals was under study widely until 2001. While the vaccine was exceedingly effective in the mouse research model, it did not offer substantial protection for uninfected partners. Thus, that promising technology, at least for now, has not seemed to be the way to go.
If you’ve read this far, congratulate yourself! Go see for yourself about what kind of research is being done around the world by going to www.medportal.com. This is a free access point to the MedLine. Put in “herpes AND vaccine” and then see what happens. Literally hundreds of published papers will come up dating back over twenty years. Search on “herpes AND England” or Bulgaria or Florence. Read the abstracts. Just remember that the facts of the published data in Europe have not been consistently reproduced in America.
If you would like more information regarding areas in the world that are experimenting with Herpes vaccine and who would consider seeing you as a patient, contactAsk the Health Care Professional on this web site.