Recently, there have been published reports of a correlation between HIV/AIDS and hearing loss.  HIV/AIDS is a topic that is not discussed enough in today’s audiological circles, perhaps because its incidence has been decreasing in most developed nations. However, HIV/AIDS remains a serious problem, and continues to be a pandemic in some parts of the world.  

Sidibé (2012) in his United Nations HIV/AIDS report that 75% of the world’s HIV/AIDS population is stable, or decreasing, but the virus is on the increase in 25% of the world, especially Sub-Saharan Africa.  Sidibe’s report also estimates that the number of people living with HIV/AIDS rose from around 8 million in 1990 to 34 million by the end of 2011.  He further indicates that that the overall growth of the epidemic has stabilized in recent years and the overall number of new HIV/AIDS infections has steadily declined, and that due to a significant increase of people receiving antriretroviral therapy AIDS-related deaths have declined.

The World Health Organization (WHO) (2013) summarized the global HIV/AIDS situation in 2013.  WHO finds that almost 78 million people have been infected with the HIV/AIDS virus and about 39 million people have died of HIV worldwide. Globally, about 35.0 million [33.2–37.2 million] people were living with HIV/AIDS at the end of 2013. An estimated 0.8% of adults aged 15–49 years worldwide have HIV/AIDS, although the burden of the epidemic continues to vary considerably between countries and regions. According to WHO estimates, Sub-Saharan Africa remains most severely affected, with nearly 1 in every 20 adults living with HIV/AIDS and accounting for nearly 71% of the world’s population living with HIV/AIDS.  The recent correlation of HIV/AIDS with hearing impairment should now be the concern of clinical audiologists around the world.

Recently, some new facts have emerged about where HIV/AIDS began and how it spread to become a worldwide problem. 

The Climate In The Congo That Fostered The “Perfect HIV/AIDS Storm”

It has been known for some time that HIV/AIDS was probably transferred from chimpanzees to humans sometime in the late 19th century.  Much as the feared Ebola virus was transferred to humans by the fruit bat being used for food, the HIV/AIDS virus transferred in much the same manner from chimpanzees.  Due to some innovative forensic viral research [Farina et al (2014)] the HIV/AIDS strains that have become a worldwide pandemic were recently tied to the 1920s development of the Belgian Congo.

The Belgian Congo is often cited as one of the most brutal and exploitative colonial regimes in modern history. According to Kakutani (1998) the Congo stands as an extreme example of the cruelty of European colonial rule in Africa for the sake of economic gain. The real story of how the HIV/AIDS virus was spread worldwide is one of colonial greed, native exploitation and suppression, slavery, huge population increases to provide labor, and a significant increase of male population relative to females in the Congo as it developed. 

The Congo was one of the last region of Africa to be explored by Europeans. Until the late 19th century colonial Europeans had not traveled more than 100-200 kilometers inland from the Congo’s Atlantic coast due to rapids in the Congo River, the impenetrable jungle around them, tropical diseases, river cataracts, and hostile tribes.  These barriers prevented even the most well-equipped parties, such as Dr. David Livingstone and Henry Stanley from traveling too far inland.

King Leopold II desperately wanted Belgium to establish a colony to keep up with other European powers, but was repeatedly thwarted by his country’s Constitutional Monarchy government. After a major European Conference granted Leopold II license to the area, he obtained the Congo personally and set up a “humanitarian” organization to establish a purpose to claim the Congo, setting up several shell companies to complete the deal. Thus, the Congo Free State (1886-1908) was born.

Meanwhile, the American Henry Stanley sought a financier for his dream project—a railway past the Congo River’s lower cataracts that would allow steamers on the upper 1,000-mile section of the Congo River and open up the wealth of the “Heart of Africa”. Leopold found a match in Stanley, and tasked him with building a series of forts along the upper Congo River and buying sovereignty from tribal leaders (or killing those unwilling). Several forts were built on the upper Congo, with workers and materials traveling from Zanzibar as well as slaves from the Congo area.

In 1883, Stanley managed to travel overland from the Atlantic to Stanley Pool. When he got upriver, he discovered that a powerful Zanzibari slaver had got wind of his work and captured the area around the Lualaba River, allowing Stanley to build his final fort just below Stanley Falls (site of modern Kisangani).  This led to the development of the railroad in the Congo Free State and later in Belgian Congo. 

Under Belgian rule from 1908 -1960 there were two economic booms, one in the 1920s and another in the 1950s.  The 1920s boom that led to the spread of HIV/AIDS occurred when the railroad was being built to haul copper, rubber and other prime commodities from the Congo to other parts of Africa and ultimately to Europe.  Africa’s railway network began in 1852 in Alexandria, Egypt and continued developing until the 1960s. While most of the main lines were completed by the 1920s, they were extremely expensive to build, both in terms of the loss of life and financial cost.  Those lines that required the most expense were built in the thickest jungle and around river cataracts , such as the Belgian Congo were built last. 

Recent viral forensic research by Farina et al (2014)  has traced strains of genetic codes for the HIV-1 Virus back to 1920s Leopoldville  (now Kinshasa) but their question was, why did one strain of the virus eventually expand globally while other strains remained local?  The answer is in the development of the region.  The 1920s were when the Congo railroad was being built.  Gallagher (2014) reported that during this time there was an international “perfect storm” of population growth, sex, and railways that allowed the spread of HIV/AIDS in the Leopoldville area.  Their report indicates that a booming sex trade, huge population growth, and the use of unsterilized needles in health clinics probably spread the virus.  

Additionally, the railways brought a million people a year through Leopoldville, who then took the virus to neighboring regions up and down the river and the railway. By the 1960s the virus was on its way to other continents, finally becoming a full world pandemic by the early 1980s.

It has been known that HIV/AIDS+ individuals were more prone to hearing impairment as they tend to be susceptible to infections and other maladies.  While hearing loss could be expected there was not much research that indicated the specifics of the degree of impairment that could be expected.  Very recently (December 26, 2014), JAMA Otolaryngology – Head Neck Surgery published the research of San Diego State University hearing scientist, Peter Torre, III, Ph.D. documenting a clinical correlation of HIV/AIDS with hearing impairment.  Dr. Torre’s areas of specialization within Audiology include the study of the effect of HIV/AIDS on auditory function, and he has published research on hearing loss in HIV-infected and HIV-exposed and uninfected children and adolescents.  He and his colleagues set out to determine if HIV disease variables and/or HAART are associated with changes to pure-tone threshold levels.  This current research correlating HIV/AIDS to hearing loss was funded by  National Institute on Deafness and Other Communication Disorders and the National Institutes of Health involved the evaluation of pure-tone thresholds among men and women   with immunodeficiency virus (HIV/AIDS +) and some without the virus (HIV/AIDS-). It is well known that HIV/AIDS is a virus that impairs the immune system, making people increasingly susceptible to infection and disease. While there is currently no cure, HIV+ individuals can be given a combination of medicines called highly active antiretroviral therapy (HAART) to slow the spread of the virus. Dr. Torre states that, “There have been limited data obtained on the effects of HIV-related medication use on hearing loss and in the few published studies, it is difficult to attribute the increase in hearing loss specifically to HIV medication rather than age of cumulative noise exposure.”  Torre and colleagues further write, “To our knowledge, this is the first study to demonstrate that HIV+ individuals have poorer hearing across the frequency range after many other factors known to affect hearing have been controlled for,”

Results

The study evaluated the hearing of 262 men with an average age of 57 and 138 women with an average age or 48.  Among the men177 or 44.7% were HIV+ and of the women 105 or 78.4% were HIV+.  The subjects were obtained from sites of the Multicenter Cohort Study and the Women’s Interagency HIV Study.  Pure tone thresholds were measured on all subjects in a sound treated environment at .25 to 8 kHz.  Torre and colleagues found high frequency (HPTA and low frequency pure tone average (LFPTA) thresholds were significantly higher for the HIV+ subjects, indicating that their hearing was poorer than the HIV-  subjects.  The researchers adjusted the data for CD-4 cell count, HIV viral load, and long term exposure to antiretroviral medication and the significance remained the same, greater hearing loss for those with HIV. 

Epilog

While the SDSU study did not find the physical cause for the impairment, it was felt that it could be due to inflammation or some other viral process.  Torre feels that “our hope is that by understanding how HIV relates to hearing loss, we can find or develop some medication that is therapeutic or protective against the loss of hearing.”  To those of us that evaluate hearing around the world, we should based upon this research expect hearing impairment in our HIV positive patients and counsel and provide aural rehabilitative treat as necessary.

References:

Farina, N., Rambaut, A., Suchard, M., Baele, G., Bedford, T., Ward, M., Tatem, A., Sousa, J., Arinaminpathy, N., Pepin, J., Posada, D., Peeters, M., Pybus, O., & Lemey, P., (2014).  The early spread and epidemic ingnition of HIV-1 in human populations.  Science Magazine:  Retrieved December 30, 2014: http://www.sciencemag.org/content/346/6205/56

Gallagher, J. (2014).  Aids:  Origin of pandemic ‘was 1920s Kinshasa’.  BBC News Health.  Retrieved December 30, 2014:  http://www.bbc.com/news/health-29442642

McIntosh, J., (2014). Could HIV make hearing worse?  Medical News Today.  Retrieved December 30, 2014: http://www.medicalnewstoday.com/articles/287440.php

Kakutani, M., (1998).  King Leopold’s Ghost:  Genocide With Spin control.  New York Times Books.  Retrieved December 30, 2014:http://usslave.blogspot.com/2011/04/white-king-red-rubber-black-death.html

Kiem, B., (2014).  Early spread of AIDS traced to Congo’s expanding transportation network.  National Geographic.  Retrieved December 30, 2014:  http://news.nationalgeographic.com/news/2014/10/141002-hiv-virus-spread-africa-health/

Torre, P.  (2014).  Worse lower-,higher frequency hearing in HIV+ Adults.  JAMA Otolaryngology – Head and Neck Surgery.  Retrieved December 31, 2014:  http://archotol.jamanetwork.com/article.aspx?doi=10.1001/jamaoto.2014.3302

World Health Organization (2013).  HIV/AIDS.  Global Health Observatory.  Retrieved December 30, 2014: http://www.who.int/gho/hiv/en/

Images:

Avert.org (2104).  Worldwide HIV/AIDS statistics. Retrieved December 30, 2014:  http://www.avert.org/worldwide-hiv-aids-statistics.htm

Gallagher, J. (2014).  Aids:  Origin of pandemic ‘was 1920s Kinshasa’.  BBC News Health.  Retrieved December 30, 2014:  http://www.bbc.com/news/health-29442642

Kiem, B., (2014).  Early spread of AIDS traced to Congo’s expanding transportation network.  National Geographic.  Retrieved December 30, 2014:  http://news.nationalgeographic.com/news/2014/10/141002-hiv-virus-spread-africa-health/

Lifecare, Edinburgh. Retrieved December 30, 2014:  http://www.lifecare-edinburgh.org.uk/thankyou/

Torre, P., (2014). Audiometric threshold image.  San Diego State University. The Times of San Diego.  Retrieved December 31, 2014:  http://timesofsandiego.com/education/2014/12/29/hiv-patients-experience-higher-rate-hearing-loss-sdsu-study-finds/

This week’s post brings us to the end of a very productive year (2014) for the blogs at Hearing Health and Technology Matters and especially Hearing International.  It is fitting, then, for me to thank you for your readership as well as our sponsors for their support. I hope that Hearing International will continue to meet your need to read about interesting topics in audiology and hearing presented with an international flair and just a bit different from traditional hearing blogs. RMT