Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Risk of HIV Transmission Highest in Early Stage of Infection


The risk of HIV transmission via heterosexual intercourse is highest early in the course of HIV infection, before most infected people know their HIV status, according to a new study published in the May 1 issue of The Journal of Infectious Diseases, now available online.

Conducted by a group of investigators led by Maria J. Wawer of Columbia University, the study is the first to present empirical data showing that the rate of heterosexual HIV transmission per coital act varies over the course of HIV infection. The investigators found that the risk of transmission was highest early in infection, then dropped, then rose again late in infection.

Wawer and colleagues followed a cohort of over 15,000 adults living in rural villages in Rakai, Uganda. From this population, they retrospectively identified 235 heterosexual couples in whom one partner was infected with HIV and the other partner was uninfected and monogamous. Study participants provided a blood sample and answered questions about their health and behavior, including questions on number of sexual partners and coital frequency, at 10-month intervals for up to 40 months.

From analysis of these data, the researchers found that during early infection (the approximately two-and-a-half month period after HIV seroconversion), the average rate of HIV transmission was five- to twelve-fold higher than during established infection. The infection rate was 8.2 per 1000 coital acts during early infection, compared to 0.7 to 1.5 per 1000 coital acts during established infection. The rate rose again during late-stage infection, 25 to 26 months prior to death, to 2.8 per 1000 coital acts. Among partners with newly acquired HIV infection, more than 40 percent transmitted to their partners within approximately 5 months.

These results reflect transmission rates for heterosexual vaginal intercourse only, the authors noted, and cannot be applied to HIV transmission via anal intercourse or injection drug use, since neither behavior was reported by study participants. In addition to early or late infection, other factors associated with increased transmission from the HIV-infected partner were younger age, increased viral load, and genital ulcer disease.

The study in Uganda was a collaboration between the Uganda Virus Research Institute and researchers at Makerere University, Kampala, and Columbia University and Johns Hopkins University in the United States. The study was approved by human subjects ethics boards in Uganda and the United States. All participants were offered HIV counseling and testing, health education on HIV prevention, condoms and access to STD treatment, all provided at no cost.

In an accompanying editorial, Myron S. Cohen and Christopher D. Pilcher of the University of North Carolina at Chapel Hill discussed the implications of this work for HIV prevention efforts. Traditionally, they explained, efforts have focused on those who are not yet infected and on those with established infection. The highest rate of transmission in the study, however, occurred in early infection, when few infected persons are aware of their infection status or receive the antiretroviral drugs used to treat HIV infection. Cohen and Pilcher recommended that increased attention be paid to those recently infected, and that measures such as partner notification, counseling services, and novel biological interventions be developed specifically for persons with early HIV infection.

"The challenge now," they said, "is to waste no time finding the most creative strategies to incorporate the results of this study into global HIV prevention efforts."

Steve Baragona | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg

nachricht New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>