Disparities in HIV

Have you ever wondered why 67% of all people infected with HIV live in Sub-Saharan Africa? Why is the disease such an epidemic there and not in the US? Interestingly, despite being only 13% of the US population, African Americans bear nearly 50% of the disease burden in the United States and as a group rank #16 in the world for prevalence of HIV (CDC fact sheet).


Why is there such a large disparity? Many studies have shown that traditional risk factors (numbers of sexual partners, use of alcohol and sex, smoking, IV drug use, men who have sex with men, etc.) do not account for differences in HIV and other sexually transmitted infections (STIs) between African Americans and whites even after adjusting for baseline characteristics (age at first intercourse, sex, education, marital status, etc.), but this begs the question "Why?"

Some suggest there are genetic differences that may account for the higher prevalence of disease but this theory is quickly disproved as the prevalence of a variety of sexually transmitted pathogens (viruses, bacteria, protozoans) show the same qualitative disparities (similar distribution patterns and transmission networks) for both groups. In addition, variations of STI prevalence within and between African countries suggest no common genetic link. The the rapid, dramatic declines in the disparities for curable STIs are clearly due to changes in behavior or the environment, and they show how powerful these effects can be. Biological differences suggesting the STIs themselves are the reason are also not likely related to this difference since clinical trial results regarding the impact of STI treatment on HIV incidence have been disappointing.

Racial disparities in HIV and other STIs cannot be explained by differences in behavior but that does not mean that there is no behavioral basis for these disparities, just that it is not adequately captured at the individual level. On the population level, epidemic effects operate though networks that can only be seen when individual data is linked though a simulation program, such as the one referenced below). The theory of concurrency, even when it is low grade (having two sexual partners rather than one) can rapidly connect a population and generate overall connectivity that is similar in magnitude to but more robust than that generated by super spreaders or core groups (sex workers or promiscuous individuals).

This 5-minute video demonstrates the relationship of concurrency (number of current sexual partners) with the reachability of a disease to spread to other individuals in the network.



Concurrency and Reachability video at statnetproject.org.

Background: Squares are men, circles are women, and the lines mean sexual relationship. Concurrency means a relationship that is not monogamous at any given time. At the start of the video, the middle 10 are the HIV infected individuals who in theory will pass the disease on with every sexual contact (beta of 1, which we can argue about later). Red lines mean that one of individuals was infected (with HIV) and blue means mutually monogamous.

In conclusion, the theory of concurrency (individuals having more than one sexual partners) is an alternative way to think about risk groups and risk behaviors and may lead to a more productive understanding of HIV transmission, disparities, and prevention and why Uganda and African Americans in the US have an HIV epidemic. The sexual network perspective is not only an individuals behavior that defines his or her risk; it is his or her partner's behavior and (ultimately) his or her position in a sexual network. This is demonstrated by the "trees" at the end of the video: 1. in each generation more people are infected and 2. more generations are created since the velocity has been increased in these trees. A small reduction in concurrent relationships, not necessarily promoting abstinence but simply monogamy in a relationship, can have a dramatic effect on transmission rates (as well as condom use and circumcision but I'll leave that for another blog entry).

Thanks for a great talk Dr. Martina Morris! This was one of the most interesting talks I've ever had.

Reference: Link to Morris et al. (2009) Journal of Public Health article.

Spoiled

We are staying in the University of Washington - Seattle dorms and it's quite a different environment from the extravagant DoubleTree Bethesda that we were used to. I miss the penthouse workout room and rooftop pool, the warm cookies and instant room service, flat screen television, large beds with 6 pillows, and nice, clean showers. I forgot what it's like to live and eat in a dorm. I'm sharing a tiny room that has a window that won't open and has no blinds to keep out the sun at 6am, two "closets", paper thin walls, and a shared bathroom for 8+ people that has one toilet, one urinal and ONLY one shower! Unlike soccer camps when I was young, I didn't bring my fan, pillow, clothes line or hangers, hair dryer, shower sandals and tote. Despite feeling prepared to move to an apartment in a foreign country in less than two weeks, I feel completely unprepared for dorm living! Not to mention I still haven't caught up on sleep on my three inch thick, extra-long twin mattress. I can't wait to go to Vancouver this weekend with my boyfriend Seth and see my old friends, Lauren and Jon!

A whirlwind weekend

The past 3 days I have had approximately 12 hours of sleep. Why? You may ask. This is the craziest group of intellectual people and I am currently their fearless leader.

We had our goodbye dinner on Thursday and went to a club and danced to Michael Jackson (among others) until 3am. Friday and Saturday we had to give presentations at 8am but that didn't stop the group from reliving the dance party from the night before after the Friday night baseball game.

Have you ever been to a baseball game with someone who has no idea how to play? My new friends from South Africa, Tanzania, Peru, and China went to a Washington Nationals baseball game for the first time and I spent most the time explaining the purpose: to eat hot dogs and drink beer and not really worry what the heck a strike or ball was... it was very entertaining! Cubs won 3-1.

Saturday morning attendance was sparse since most presentations were completed but I was giving our group's presentation (on 3 hours of sleep). My group was awesome and we were well prepared to discuss our proposed CIRKS study (Circumcision in Rural Kenya in Serodiscordant Couples).

Some of the ladies, including myself, went for pedicures to celebrate our completion of two intensive weeks of NIH training. A final goodbye dinner on Saturday lead to more dancing until 3 am and when our Super Shuttle arrived at 3:45am this morning I had had approximately 45 minutes of sleep. The 5+ hour flight arrived at 9:45 Western time and we've been sightseeing all day. I am exhausted!


The famous Pike Street Market with street artists, flying fish, fresh fruit, and beautiful flowers for $5-$10 a bouquet.


The Space Needle. 520 feet tall built in 1962 for the World's Fair.


The view from the top of the Space Needle of Mount Rainier, also known as Tahoma (or mother of waters) to the Native Americans and is an active volcano that towers 14,411 ft. It was a beautiful July afternoon.

Photos in the nation's capital

The Washington Monument, 555 feet tall.


View of the Lincoln Memorial and reflection pool from the Washington Monument on a beautiful morning.


View of Jefferson Memorial and the filming of "Biggest Loser" from the Washington Monument.


Fogarty Scholars and Fellows with Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. Can you find me?

"Why study global health?"

Many of you are thinking this while others are thinking, "Why do you have to go to Peru to study cardiovascular disease?" or "Why are you doing research if you are going to be a doctor?" Many have thought it but few were bold enough to ask and I respect that. So today I had to answer those questions as I was selected to be interviewed by an organization who was making a PR video for the Fogarty International Center. This is what I said:

I think global health research is important for many reasons, including humanitarian, understanding domestic diseases, and globalization. As we get better at treating infectious diseases people live longer and develop chronic diseases. Specifically, major risk factors for cardiovascular disease, such as age, smoking, family history, high blood pressure, high cholesterol, and diabetes, are increasing in prevalence leading to cardiovascular disease becoming the leading cause of death in Latin America. Most risk factors (except advancing age, family history and ethnicity) may be modified using various interventions and treatments.

The prevalence of diabetes mirrors the increased prevalence of obesity in the US. Genetics and environmental factors play a significant role in the development of diabetes and cardiovascular disease but defining these in developing countries is important. However, as with most governments, policy leader need to see the facts and data that this is actually a problem in their area or country in order to make create change.


Graph from PRB.

Fact: $1 of every $3 Medicare dollars is spent on diabetes in the US yet chronic disease attracts only 5% of the entire World Health Organization budget. In the US, global health research has seen a large grassroots movement that started with idealistic students and health care professionals. My goal is to do good scientific research this year to advance our understanding of cardiovascular disease in Peru, help raise awareness on an individual level, and generalize the results to populations in other areas. The rest I'll leave up to the politicians.
The burden of chronic disease is shifting to developing countries that do not have the resources, primary care medical infrastructure and awareness of policy makers and individuals to effectively manage this problem. Therefore, I feel that it is our duty as global citizens to help reduce the burden of poverty and inequalities in health. Join the ProCor mailing list to get updates: >. Also an interesting site of WHO statistics.

Quotes of the week:
"It's a bold new move to completely embrace that chronic diseases are and will be the biggest burden in the developing countries." Dr. Cristina Rabadan-Diehl, director National Heart, Lung, and Blood Institute

"It pays to listen to the people suffering from the disease." Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases.
"Humanitarian reasons are like relationships, you know, they come and go, you can always find another one." Dr. Anthony Fauci explaining why we need global health research.

"The more tools you have in the toolbox, the better prepared and useful you'll be." Dr. Steven Reynolds, MPH, who works on HIV in Uganda

"In battle no plan remains in tact." Dr. Pierce Gardner emphasizing how important it is to be flexible this year with regards to our projects.

"Luck comes to the prepared mind." Dr. Larry Laughlin and old friend of my mentor, Dr. David Williams.

Hanging out with Fogarty Scholars

Most of the Peruvian crew standing outside our lecture building at the NIH with Dr. Bob Gillman from Johns Hopkins.

Fogarty Orientation Days 1-3

This has been the most inspiring three days of lectures that I have ever had! I love it! There are about 70 students here at the National Institutes of Health in Bethesda, MD, half from the US and half from abroad. We have varied levels of training from medical students to PhDs, and in all specialty areas from cardiology to veterinary medicine.

Dr Pierce Gardner, one of the founders of the Fogarty International Clinical Research Scholars program, said today "The concentration of idealism that I am immersed in today is so exciting and makes me feel goot that the world is going in the right direction." It is fun to be surrounded by such amazing people with diverse backgrounds and experiences who are all passionate about global health and research.

Here's a quick review of my Fogarty Orientation.
Flight. Expensive. Basically, I was charged $90 for packing over 50lbs plus $40 for having two carry-on and the rolling suitcase broke when I arrive. On a good note, I'm moving to Peru and all my stuff fits in two (kinda) bags.

Registration. Simple.
Hotel. Sweet with a rooftop pool!
Roommate. Awesome. My foreign "twin," Romina, is from Peru and speaks perfect English (to my pathetic Spanish). She is very friendly and pursuing a PhD in Epidemiology in Lima. I look forward to working with her and going on lots of adventures this year with her (and the 10 other from the Fogarty who will be in Peru with me).

Who's the most famous Macalester alum? Anyone... Kofi Annan, former UN Secretary General! We talked a bit about him today and his initiative to get world leaders to make a commission on macroeconomics in 2000 which lead to the Millennium Development Goals. Check 'em out. http://www.un.org/millenniumgoals/
The goals are simple: to end poverty by 2015. Are we there yet? NO WAY! But that's where the Fogarty comes in as many of these goals are interconnected with health and improving the health of a community can have a significant impact on quality of life, education, and productivity. But what are the health problems, what is the epidemiology of these disease, how do cost-effectively treat, and how do you measure if your interventions are having an impact? That's why I'm here: to learn how.

Epidemiology 101: How do you take a pulse on a population?
Col. Michael Lewis spoke today about how we transition our thinking from clinical medicine to epidemiology, aka individuals with disease we treat to populations where we prevent and control disease. This crash course was a nice review of public health, epi, and biostatistics. I hope to conduct research on primary and secondary prevention of cardiovascular disease, or simply put, preventing the disease by removing the risk and/or delaying the disease occurrence. Most of the current research in cardiology is on secondary prevention and screening and detecting disease or tertiary prevention where we try to minimize the effects of the disease and associated disability.

Microeconomics 101: I have never taken econ but this was the best health economics crash course. Rachel Nugent from the Center for Global Development, a DC think-tank, talked about cost-minimization (where we look at the costs associated with achieving a specific goal. Example: a huge campaign to deliver vaccinations to children in Africa), cost-effectiveness (where we compare the costs per unit of a health metric, like disability-adjusted life years, a fancy way to quantify morbidity and mortality of any medical condition. Example: is it more cost effective to do family planning or educate young girls to decrease greenhouse emissions?), and cost-benefit (which is very difficult to do in healthcare because it compares costs across sectors. Example: what has a greater benefit educating all young girls in a country or vaccinating children against name-your-disease? or does it make a difference if we do blood pressure screening vs build sidewalks in a community?). Very interesting discussion with lots of ethical questions as well. Do you diagnose if it's not cost effective to treat? Interestingly, if an intervention is lower than three times the average annual income per person than it is deemed "cost effective." For the US that's $90,000/yr, for Peru it's $5400/yr and for Mali it's $1800/yr.

Research in Developing Countries 101. Inspiring. Neglected tropical diseases (NTD) (hookworm, roundworm, trichuriasis, schistosomiasis, elephantiasis, trachoma (blindness), opisthorchiasis (liver fluke), and onchocerciasis (river blindness) are all chronic, debilitating diseases since they occur largely in endemic areas and individuals typically cannot fight them off. They are not as sexy at HIV/AID, malaria or tuberculosis but according to the DALYs, they cause almost as much morbidity and mortality as ischemic heart disease worldwide, and more than stroke or malaria. There are 1.4 billion people who live on less than $1.25/day, aka no money. Most live in urban slums or are subsistence farmers in 58 nations and 73% of these "bottom billion" live in areas of conflict or civil war. For example, Haiti has 8 million people with five or more NTDs and for only $0.50/yr, or $4 million, we could treat these NTDs by giving one time dose of four antibiotics. How many visitors go to Haiti every year? 20 million, How much do they spend? Billions. If every person gave $1 when the visited we could treat the NTDs for five years. Wow.
In addition, there are many neglected diseases in the US where there are 300 million people, 12% who live in poverty (<$30,000/year) and are largely burdening minorities. Access to healthcare in the US is also a barrier, as it is abroad. We have to work to educate people to decrease DALYs from NTDs.

Ok I'm off my soap box... next time I'll just talk about the cultural things, like my personal tour of the US Capital on Saturday!

Step 2

St. Anthony Fall, Minneapolis, MN in the spring.


The view of downtown Minneapolis and the University of Minnesota from the Witches Hat water tower in Prospect Park open only once a year.

The unfortunate part about medical school is that they make you take tests, lots and lots and lots of them.

The MCAT was nothing compared to the USMLE Step 1 board exam that I took last year - everything from the first two years (and much more) crammed into an 8 hour exam. Now, after a full year of clinical rotations, the USMLE Step 2 Clinical Skills exam that I took three weeks ago was a $1400 (not to mention I had to fly to one of five cities where it is offered) day in a standardized "fake" clinic. Basically it is an exam to test your English since most people taking the exam are foreign medical students. I feel bad for them since I studied two days and they had been studying for months.
Anyway, yesterday I took the USMLE Step 2 Clinical Knowledge exam - 9 hours of grueling multiple choice questions (A-N sometimes) on clinical scenarios. Overall, not as bad as the MCAT or Step 1 but still not terribly fun. Oh well, time for the next chapter in my life... Peru!

I am moving to Peru for the next year because I received the National Institutes of Health Fogarty International Clinical Research Scholarship. I will be doing cardiovascular disease research in Lima and Arequipa, Peru. Non-infectious diseases are now the #1 killer of Peruvians (just like in the USA) and not very much is known about their unique risk factors, genetics, resources, prevention programs, awareness, etc. in the community. I will be taking a year off of medical school at the University of Minnesota and will graduate in May 2011.

I will go to Washington DC to train at the NIH from July 5-19 and then to Seattle, WA form July 20-30 to take the STD/HIV and Principles of Research course and then fly to Lima July 31. I will return to my humble Minnesotan home June 2010.
Wish me luck!
I look forward to hearing from you on this wonderful adventure!