Don't Expect an HIV/AIDS Vaccine, Researchers Say

Steven Mosher
by Joan Robinson
PRI Weekly Briefing
Vol. 13 / No. 3
28 January 2010
Reproduced with Permission
Population Research Institute

Our hearts go out to infant victims of HIV/AIDS, with their skeletal limbs and rib-ridged stomachs, and some would argue that these could be saved by the development of an HIV/AIDS vaccine.

Not Dr. Bonnie Dunbar, the founder of the Africa Biomedical Center in Kenya, who works daily with victims of HIV and other infectious diseases. Speaking at the 4th International Public Conference on Vaccination, the famed researcher argued that billions of dollars are being wasted on research for an HIV/AIDS vaccine, when there are far more pressing African health needs to address.

Over the years, Dr. Dunbar has received many awards for her efforts to develop a contraceptive vaccine. She recently abandoned this research because all of her trial vaccines turned out not to contracept, but to sterilize, destroying the ovaries of the animals into which it was injected.

Because of her decades of experience in Africa, Dr. Dunbar knows what we in the West have forgotten, namely, that Africans suffer not only from HIV/AIDS, but also from many other STDs and infectious diseases. Not only that, but acquired drug resistance, malnutrition, dehydration, and terrible sanitary conditions are a problem throughout sub-Saharan Africa. All of these factors combine to render Africans particularly susceptible to HIV/AIDS.

Indeed, so compromised are the immune systems of many African children and adults that Dr. Dunbar questions whether they are capable of the immunological response required for a vaccine to be effective. She believes that increased attention to basic health care needs through improved diet and clean drinking water might do much more to reduce disease than a vaccine.

Moreover, not only is there no effective HIV/AIDS vaccine available at present, she believes that it may be impossible to develop one.

Dr. Chuck Wira's celebrated research in reproductive immunology, combined with her own findings, have convinced her that any vaccine for HIV/AIDS will do nothing to prevent heterosexual transmission, which is the chief problem in Africa.

The reasons for this are highly technical, but let me summarize as best I can. First of all, according to Dr. Dunbar, a woman's uterus has very susceptible HIV receptors. And immune responses on the part of the reproductive tract won't stop HIV.

Why is this? For two-thirds of the month the reproductive tract is very active, in an immunological sense. The cervix secretes antibodies that react against foreign bacteria (and sometimes against sperm). The uterus has active cell immunity. The oviducts secrete endogenous microbicides to attack bacteria.

But then, right in the middle of a woman's cycle, the entire immune system of the reproductive tract shuts down for ten days. It shuts down in order to avoid attacking incoming sperm, which are totally foreign, and to protect any fertilized zygotes -- tiny human beings -- who may be conceived. The hormones of mid-cycle cause both the humoral and cellular immune systems to be depressed so as to facilitate fertilization and implantation.

As Dr. Dunbar explains, "That's the body saying, 'Oh, we've got to hold back. We need that embryo and we need that embryo to implant and we can't attack it.' So this again is the beauty of Mother Nature, helping perpetuate the species through effective reproductive biology."

So what does all this mean for the development of an HIV/AIDS vaccine? According to Dr. Dunbar, "The implications for heterosexual transmission of HIV/AIDS and some of these other diseases is that for ten days it doesn't matter what you have in your blood system [by way of antibodies] _ your reproductive tract is going to be shutting down, totally independent. . . . And so a vaccine that induces either humoral or cellular immunity would not be likely to be effective for preventing STD infections or HIV during mid-cycle in the female."

"No one to my knowledge has really looked at this in the vaccine development." Dr. Dunbar concluded. "I think this is one of the reasons why they've not been successful in many cases."

The billions of dollars being spent on HIV and STD vaccine development would be much better spent on basic food and water, Dr. Dunbar asserted. "I would like to say that poor nutrition and water sources are basically our nightmare in Africa. Our most effective vaccine is a glass of clean water."

Though I agree with Dr. Dunbar in her plea for clean water and nutritive food, we parted company when she called for more "population control" in Africa.

In the past, she has worked as a staff scientist on population issues with The Population Council, Rockefeller University, and as an advisor to USAID and WHO in the population-target developing nations of China, India, South America, and Africa. She continues to believe that, "If population growth and other basic health issues are not addressed immediately on the global scale, emerging disease problems as well as environmental damage, global warming, will cause insurmountable problems." But on the question of an HIV/AIDS vaccine, I think that she is a thoroughly credible witness.

If the African people are able to access the clean drinking water and grow the nutritious food that their countries are capable of producing, disease of all kinds, including HIV/AIDS, will decrease.

We could help.