A collaborative group of scientists from the Centre Muraz (Burkina Faso), the University of Montpellier (France) and the London School of Hygiene & Tropical Medicine (UK) carried out the trial among women co-infected with the human immuno-deficiency virus (HIV) and the virus that causes genital herpes (HSV-2) in Burkina Faso. The results showed that having the herpes virus increased the replication of HIV, and also revealed that the quantity of HIV in the blood and in the vagina was reduced by continuous anti-herpes treatment over 3 months.
These findings open new avenues for the prevention of HIV transmission and for the management of patients co-infected by the two viruses.
In 2005, an estimated 4.1 million people were newly infected with HIV, mostly through heterosexual intercourse1. This alarming number of infections highlights the urgent need to intensify and expand proven prevention methods, and further, to identify and implement new methods of HIV prevention.
A number of observational studies have indicated that HSV-2 enhances the risk of HIV-1 acquisition by around three-fold2. HSV-2 infection may also increase HIV-1 infectiousness by disrupting the genital mucosa and increasing the levels of HIV in the genital tract3, allowing easier transmissibility of the virus. In addition, the HIV viral load in the blood of HIV-1 infected patients increases, at least temporarily, during episodes of HSV reactivation.
Lead author Dr. Nicolas Nagot, of the London School of Hygiene & Tropical Medicine (LSHTM), explains: ‘Behavioural interventions are not always successful, as knowledge does not necessarily translate into sexual behaviour change. Therefore, innovative methods that target the biological susceptibility of individuals to acquire or transmit HIV are also required. A number of options to prevent HIV transmission are currently being investigated, including the role of vaginal microbicides, pre-exposure HIV prophylaxis, male circumcision, and - in the future - an HIV vaccine.’
‘The results of the trial are striking’, he adds. ‘They show that valacyclovir significantly reduces the frequency and quantity of HIV detectable in genital secretions and, in addition, reduces the quantity of HIV in the plasma. As expected, there was also dramatic reduction in the detection of symptomatic and asymptomatic presence of HSV-2. The effects appeared to gradually increase over the 3 month follow-up period, with no sign of abating.’
These results indicate a new way to possibly reduce the sexual transmission of HIV from already infected individuals to their partners, since the frequency and quantity of HIV in the female genital tract are closely related to the transmission of the virus.
The findings will need to be confirmed by further research, and there is already a large ongoing trial that is measuring direct transmission of HIV between discordant couples in several sites worldwide.
Dr Philippe Mayaud, one of Dr Nagot’s colleagues at the LSHTM concludes: ‘Our results have important potential implications for public health and clinical practice, as HSV-2 control could become a new form of HIV prevention targeting HIV-infected individuals, as well as providing clinical benefits. Importantly, an HSV vaccine that would either prevent HSV infection or diminish the clinical and sub-clinical manifestations of HSV with a similar efficacy on HIV as HSV suppressive therapy, would represent a long-lasting form of HIV prevention. The development and evaluation of an HSV vaccine should rank high on the international research agenda.’
Gareth Thomas, UK Minister for International Development, whose department DFID has provided supplementary funding for the research, said: "These exciting initial findings demonstrate why research into reducing HIV/ AIDS transmission is such a vital element of the fight against the disease. The UK Government has pledged to spend £1.5 billion tackling HIV/AIDS in developing countries between 2005 and 2008. We will follow the next stages of this research with interest."
Philippe Mayaud | alfa
Flavins keep a handy helper in their pocket
25.04.2018 | University of Freiburg
Complete skin regeneration system of fish unraveled
24.04.2018 | Tokyo Institute of Technology
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
25.04.2018 | Physics and Astronomy
25.04.2018 | Physics and Astronomy
25.04.2018 | Information Technology