Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Risk of HIV Transmission Highest in Early Stage of Infection

07.04.2005


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:
http://www.idsociety.org

More articles from Health and Medicine:

nachricht Using fragment-based approaches to discover new antibiotics
21.06.2018 | SLAS (Society for Laboratory Automation and Screening)

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

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: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>