CDC's Kevin Fenton Discusses HIV Incidence in the United States
August 3, 2008
LARRY LEVITT: Kevin Fenton thanks for joining us.
KEVIN FENTON: Thank you.
LARRY LEVITT: The CDC just released new numbers on HIV incidence, the number of new infections each year; give us a sense of what the main findings are from this new report.
KEVIN FENTON: Sure. Well, this recent report in JAMA really reports on breakthrough technology, which is really giving us the clearest picture of the HIV epidemic in the U.S. to date. Essentially one of the key findings of the study is the level of new HIV infections in the United States, also called HIV incidence.
And the report indicates that the level of new HIV infections in the United States is higher than had been previously known, in fact approximately 40 percent higher than early estimates in the '90s and in the early 2000s.
The data also confirmed that HIV incidence really is taking its toll on some of the subpopulations in the United States; for example, gay and bisexual men of all races and African American men and women. These data really are a wake-up call for all of us in the United States to really begin our thoughts on where we need to be going for prevention and how we need to be enhancing prevention moving forward.
LARRY LEVITT: You talked about the infection numbers being higher than were previously thought. What does the new report say about the course of the epidemic over recent years? Is it getting worse? Better?
KEVIN FENTON: Well one of the fantastic things about the JAMA paper is that we have combined two different methodologies to give a sense of not only what incidence is -- i.e. in 2006 -- but how incidence has actually changed over time, and we used an extended back calculation method, which is a mathematical method of imputing HIV seroconversion based on knowledge of AIDS diagnoses or HIV diagnoses and patterns of HIV testing in the U.S.
And what the extended back calculation method shows is that HIV incidence in the United States peaked in the mid to early 1980s and had declined subsequently. It also shows that HIV incidence has in fact remained relatively stable in the U.S. since the late 1990s.
LARRY LEVITT: And any sense why the declines stalled? I mean why have we not seen continuing declines in new infections?
KEVIN FENTON: Well I think we also need to think more generally about explanations for various trends that we are seeing since 1977. Clearly the dramatic declines in incidence that we saw during the late 1980s and early 1990s were really a reflection both of population-wide efforts to stem the tide of the disease as well as widespread individual changes in behaviors, increasing awareness about HIV and a population response to HIV.
The stability in HIV incidence since the late 1990s is in a simple sense some sign of progress. Remember that there are more people living with HIV in the United States today than ever before. These people are living longer and healthier lives with HIV yet HIV incidence has remained relatively stable since that time, so the key challenge moving forward is what do we need to do to get ahead of the curve?
How do we need to enhance and intensify our prevention efforts to ensure that we are meeting some of the unmet need which still exists in the society today?
LARRY LEVITT: And you talked about the decreases in incidence and the stabilization being in some sense a sign of success of prevention efforts. On the other hand, you are now reporting a higher number of infections than you previously thought. Does that have implications for the current level of effort for prevention or where your targeting prevention is more needed?
KEVIN FENTON: Well these data are clearly a wake-up call. Having more than 56,000 new HIV infections occurring each year in the United States is not acceptable and we as a society need to think about what we all need to be doing at the individual level, in communities, and as a society to bring this epidemic to an end within our lifetimes.
The data also confirmed that HIV incidence is quite marked among gay and bisexual men of all races. There are many reasons to explain why we are seeing some of these high trends and in fact we have some inkling of this from the higher rates of sexually transmitted diseases as well as some of the coterminous epidemics of drug use and substance abuse, homophobia, stigma among the gay community.
These are all highlighting to us the importance of targeting our efforts, of meeting some of the unmet need which still exists in our society today and of intensifying our efforts, whether for gay and bisexual men, for minority communities, or even for young people, where we know we are seeing high numbers of new infections occurring each year.
LARRY LEVITT: So when looking at these high risk groups -- men who have sex with men, African Americans, injection drug users -- give some examples of what an intensified effort might look like. What are some of the things we could be doing to improve prevention among those groups?
KEVIN FENTON: That is such a great question. The key thing that we must remember is that prevention works and there are effective prevention interventions that can be applied at the individual level; for example encouraging reductions in sexual partners, practicing abstinence, using condoms consistently and correctly every time, knowing one's HIV status -- these are effective strategies which can help individual awareness of serostatus and therefore ensure that individuals make effective choices about their risk of onward transmission or acquisition of HIV.
For communities, there are some effective strategies that need to be put in place; for example, insuring that there is adequate access to effective prevention services, looking at ways of providing HIV testing services within communities.
Communities can also play a very strong role in tackling stigma, discrimination, homophobia, and communities also have a role to play in addressing some of the social determinants of disease transmission in the United States today, which can really have an upstream effect on reducing HIV transmission rates downstream, so there are interventions that we all can put in place whether as individuals, whether in our communities or as a society to stem the tide of this disease.
LARRY LEVITT: And was there anything in this report that surprised you, that really stuck out as something you did not realize before that causes you to rethink CDC strategy?
KEVIN FENTON: No. You know, although the numbers are somewhat higher than had been previously known, the trends themselves as well as the burden of HIV incidence really confirmed what we had known from other surveillance sources, for example our AIDS diagnoses as well as our HIV diagnoses surveillance. Perhaps what is most marked are these three features.
First, that HIV incidence among gay and bisexual men really has been on the increase since the early 1990s and our data suggests that we are seeing sustained increase in HIV incidence in men who have sex with men. Now HIV incidence is nowhere near as high as it was in the '80s but nevertheless these are worrying trends and really call for us to really focus on intensifying our efforts with men who have sex with men.
Another key finding was the proportion of new diagnoses which are current among young people. About a third of new diagnoses are occurring among young people aged less than 30 years and this suggests that we are losing the battle somewhat in getting an AIDS-free generation.
So we need to intensify our efforts with young people, whether in the schools, in home, at universities and communities to ensure that we are reiterating messages on HIV prevention for another generation of Americans who are becoming sexually active and who are developing new partnerships in the field. So there is more of a confirmation of things that we knew, providing a clearer picture of where we need to go and a call for us all to really enhance our prevention efforts moving forward.
LARRY LEVITT: You talked about the number of people living with HIV and AIDS increasing over time. Are there implications from these numbers for those estimates, the number of people in the U.S. who are living with HIV and AIDS?
KEVIN FENTON: Well the last time CDC released prevalence estimates for HIV in the United States was data for 2003, so we are planning to release new prevalence data on HIV in the United States later this year. Now it will be very premature for me to speculate what that new prevalence estimate would be.
But most importantly, what I would like to reassure listeners is that the new methods that we have used to calculate incidence are very different to the methods that we use to calculate prevalence and we should not try necessarily to impute one for another. We will really have to look at what the new prevalence estimates are later this year.
LARRY LEVITT: Aside from those new prevalence estimates, what are the next steps that we can expect in terms of prevention strategies or new directions?
KEVIN FENTON: Well first of all let me just give you a heads up on ways in which we will be enhancing our data moving forward. The data in the JAMA paper really are the first cut at incidence in the United States and really in the paper we have looked at broad demographic categories.
For example, HIV incidence for men and women or across the racial and ethnic groups or across transmission categories. Later on this year, we will be producing data at a more granular level, in other words looking at population subgroups and especially focusing on some of those subgroups that we are particularly concerned about.
For example young gay men or black gay and bisexual men or for example African-American women or Latino women so these data will really give us some greater focus on where new infections are occurring and how we need to enhance our efforts.
As far as our prevention strategies are concerned, CDC has already begun to look at our prevention portfolio and to respond to these data. We are focusing our efforts to mobilize communities whether it is the African American or working with our Latino community partners.
We are looking more critically at the research that needs to be done so that we have new prevention tools to use to enhance and to target our prevention efforts. We are also working with our state and local health department partners to ensure we are holding both accountable for using the prevention dollars wisely and effectively.
And we are also working with our partners to look more critically at what more needs to be done as we think about enhancing our efforts with men who have sex with men. There are many things that CDC will be doing as we move forward but I also want to reiterate that this is not only CDC's responsibility.
This is everyone's responsibility as a nation and we all need to think about what more we can do moving forward to bring an end to this disease.
LARRY LEVITT: That is certainly part of what we will be doing over the next week at the conference here in Mexico City. Kevin thanks for speaking with us.
KEVIN FENTON: Great, thank you so much.
This transcript has been lightly edited by TheBody.com for clarity.
This article was provided by kaisernetwork.org.