The emergence of HIV/AIDS in the Americas and beyond
Although HIV-1 subtype C dominates the HIV epidemics in Africa and India, HIV-1 group M subtype B is the most widespread HIV variant. A new analysis of HIV genomes reveals that a virus originating in Haiti was the ancestor of virtually all HIV/AIDS cases outside Africa. HIV spread from Africa to Haiti in or around 1966, and from there entered the USA, probably arriving in just one person in about 1969, earlier than previously believed. After that, the results suggest that the virus circulated cryptically in the USA for 12 years before the recognition of AIDS in 1981.
The emergence of HIV/AIDS in the Americas and beyond. PNAS USA, October 31, 2007
HIV-1 group M subtype B was the first HIV discovered and is the predominant variant of AIDS virus in most countries outside of sub-Saharan Africa. However, the circumstances of its origin and emergence remain unresolved. Here we propose a geographic sequence and time line for the origin of subtype B and the emergence of pandemic HIV/AIDS out of Africa. Using HIV-1 gene sequences recovered from archival samples from some of the earliest known Haitian AIDS patients, we find that subtype B likely moved from Africa to Haiti in or around 1966 (19621970) and then spread there for some years before successfully dispersing elsewhere. A “pandemic” clade, encompassing the vast majority of non-Haitian subtype B infections in the United States and elsewhere around the world, subsequently emerged after a single migration of the virus out of Haiti in or around 1969 (1966-1972). Haiti appears to have the oldest HIV/AIDS epidemic outside sub-Saharan Africa and the most genetically diverse subtype B epidemic, which might present challenges for HIV-1 vaccine design and testing. The emergence of the pandemic variant of subtype B was an important turning point in the history of AIDS, but its spread was likely driven by ecological rather than evolutionary factors. Our results suggest that HIV-1 circulated cryptically in the United States for 12 years before the recognition of AIDS in 1981.
Related:
- Rooting the tree
- What do we really know about the spread of AIDS in Africa?
- Smallpox came from Africa
Tags: Biology, Health, HIV/AIDS, Medicine, Microbiology, Science
The Association of Haitian Physicians Abroad (AMHE) responds to Worobey study, November 7, 2006
The Association of Haitian Physicians Abroad (Association des Médecins Haitiens à l’Etranger or AMHE) has reviewed the recent article by Thomas Gilbert and colleagues, reporting a phylogenetic analysis of archival blood samples collected from five early recognized AIDS patients at Jackson Memorial Hospital in 1982-1983.
The study authors identify these five patients as Haitians who left Haiti after 1975. This article has several important limitations and does not provide any scientific breakthrough. Before a detailed critique of this paper, AMHE would like to point at the following remarks in methodological biases that may explain some of the study findings. First, the bias in selection of early samples of HIV among Haitians is quite obvious. The investigators chose a convenient sample under the unproven assumption that all these Haitian immigrants acquired HIV infection in Haiti. They obviously ignore that the clinical course of these patients perfectly fits the natural history of HIV/AIDS. No culturally-sensitive epidemiological investigation has ever been conducted of these initial Haitian immigrants presenting with HIV infection at Jackson Memorial Hospital in Miami. Therefore, the assertion that they contracted HIV in Haiti is presumptuous and not based on facts. Moreover, no archival samples from Haiti are included in the phylogenetic analysis and this constitutes a serious flaw. We do not know either how many samples of the pandemic clade B might have come from Haitian subjects, which raises the prospect of misclassification.
Second, the authors do not adequately report on some of their methods and results. For example, they do not specify clearly the number of sequences for which there was uncertainty as to which subtype they belonged to; neither do they try to replicate their results by sequencing other HIV genes. While computer simulation techniques and phylogenetic analyses are important to our understanding of biological evolution, the application of these methods with such serious methodological limitations does not prove unequivocally the origin of the pandemic clade B subtype in the United States.
Because these findings lack scientific validation, we need to raise questions about the motives of the authors; their paper not only does not advance our knowledge of the HIV epidemic but it continues with a dangerous precedent of victimizing an ethnic group with flimsy data. Needless to say that such half truths have been very harmful to the country and its people. The hasty classification of Haitians as a group at risk for HIV more than 20 years ago can be considered as a cloud hanging over good scientific practice. It destroyed the tourist industry in Haiti; its citizens have since been suffering from the social stigmata of presumed carriers of dangerous germs even though that classification was finally removed by the CDC.
We are also afraid that such mishandling of data can have the unintended consequence of the refusal of Haitian patients to participate in research studies at American Universities for the fear that they will be used as guinea pigs in the furtherance of biased scientific protocols and conclusions. That would be the saddest of ironies for we all need good science to help us all against this calamity.
La Science sans conscience n’est que ruine de l’âme.
Christian Lauriston, MD
President of the Central Executive Committee of AMHE.
http://www.solutionshaiti.blogspot.com
There is another thing wrong with this article, and with all of the commentaries that have followed it into newspapers and magazines – and that is that it ONLY describes the genesis of HIV-1 subtype B, which is by no means the most important. Subtype C infections constitute the single biggest group; throw in the circulating recombinant types largely composed of subtype C and suddenly that’s most of the infections in the world…much of Africa, all of India and China….
VERY Amero- and Eurocentric, I am afraid!
The study doesn’t specify if the haitians had contrated the virus in Haiti or after they left Haiti. They might have contracted the virus after they came to USA. The Author of the study started the study with a misleading hypothesis.
BInslas Anilus/ Radiation Therapist