About a month ago, I included advancement on an HIV vaccine as one of the things to watch for in 2013. And while I can’t claim that we’re on the verge of rolling out an approved vaccine just yet, there has already been some progress trickling through in the first month of the year.
In addition to the previous advances a Canadian team has made on an effective HIV vaccine, a Spanish team of researchers has now made some limited progress on a therapeutic vaccine, which they will continue to improve over the coming years. And perhaps even more interestingly, an Australian team has recently released some early-but-promising results on their work that uses a specific protein mutation in HIV to turn the virus on itself and very effectively prevent clinical progression to AIDS.
All of this work is promising, and it’s starting to feel like we’re back on track for a successful therapeutic vaccine in the next decade. And while a therapeutic vaccine isn’t the ‘win’ that a prophylactic vaccine might be, since we know that treatment is prevention, then any significant boost to treatment – like a therapeutic vaccine – has the promise to tip the scales towards ending the HIV epidemic.
And then what?
This is about the time when someone like my grandmother will ask, “Have you thought about what you’ll do if they ever cure HIV?” My answer is always the same, two part, bi-polar response:
First: Yes, I’ve thought about it. A lot. It would great if we could put and absolute end to HIV! I have so many plans, so many other health issues that I’d love to work on!!
Second:…but if you put an effective vaccine in my hands today, I’d be willing to bet you anything that I still have a lifetime’s worth of work ahead of me on HIV…
Why is this? What could possibly entail a lifetime’s worth of work once we have an effective therapeutic vaccine? For starters…
- Education – getting the word out to all levels, from policy-makers to medical practitioners, to the community of people living with HIV, in every region of every country in the world…this will take time. Even after people know about a vaccine, convincing certain groups that it’s not a hoax may take some work. After over 15 years of effective combination therapy using ARVs, we still find people who doubt whether ARVs are effective; and on the vaccine side, diseases like polio are still with us because some groups decline to vaccinate. So, finding an effective vaccine and getting people to believe it works will be at least two separate tasks.
- Funding & Systems – the legions of people around the world who work on childhood immunization campaigns must groan when the idea of an HIV vaccine comes into play. As noted above, they’re still fighting valiant battles with ‘old’ foes like polio, and, in 2012, 67 countries attained less than 90% coverage for measles-containing vaccines. While some of these shortcomings may be due to educational gaps, major challenges remain in securing regular funding to not only purchase the vaccines, but to build and maintain the systems that distribute them. This means complex strengthening efforts for human resources and infrastructure before any HIV vaccine could be effectively rolled-out.
- Reaching populations - the fact is, we already have some pretty solid prevention and treatment tools, and we still fail to reach many of the most-at-risk individuals. Many among the key populations of people who inject drugs, sex workers, and men who have sex with men aren’t reached regularly with prevention messages and commodities (condoms, needles/syringes), and testing and treatment among these groups remains devastatingly low. We can’t expect that reaching these same populations with a vaccine would be any easier.
- Follow-up - much like reaching populations to initiate vaccination, follow-up will be challenging. We don’t yet know whether a therapeutic vaccine would require a series of injections (though one could guess that it might), and we don’t know what kind of regular resistance testing might be required to assure that the vaccine is working sufficiently in a large enough group of people to be providing a herd immunity-type effect. So, take all of the problems above, and extend them into a lengthy follow-up period.
And that’s just for the therapeutic vaccine, which would be given to individuals who are already infected with HIV. What might we face if a prophylactic vaccine became available, and mass immunization campaigns became the norm? Systems would clearly be stretched even further, but would we have other problems as well? Would we have to argue about sexual disinhibition, as we did for the HPV vaccine? Will we ration the vaccine to high-prevalence areas (e.g. sub-Saharan Africa), or will we recommend vaccination for all children, regardless of the type of epidemic?
While the scientific bench work might be done in my lifetime, this is why I tell Grandma that I see a long future of working on HIV as a public health specialist…