Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

US syphilis epidemics not driven by increases in unsafe sex say researchers

27.01.2005


A UK based team of researchers has found that regular epidemics of syphilis in the USA are due to the intrinsic cyclical nature of the disease. They show that changes in the immunity of the population cause periodic syphilis outbreaks, rather than changes in sexual behaviour, as was previously thought.



According to research published today in Nature, the team from Imperial College London and funded by the Medical Research Council and the Royal Society suggest that syphilis outbreaks, previously attributed to social phenomena such as the sexual revolution or the gay liberation movement, are actually caused by a loss of immunity among those at risk of infection.

Dr Nicholas Grassly, from Imperial College London, based at St Mary’s Hospital and one of the researchers said: "While we do not dispute the fact that syphilis is transmitted by unsafe sex, our findings suggest that change in population immunity is the main reason for periodic epidemics of syphilis, not change in sexual behaviour."


After analysing data from 68 cities across the USA since the 1940s, the team found that rises and falls in the disease followed a distinct pattern that was repeated over a 10-year cycle. Rises in syphilis cases can be explained by falling population immunity. Immediately after an epidemic, immunity is at its highest. It then takes time for immunity to drop to a level when an epidemic can occur again.

The team compared syphilis case reports with gonorrhoea reports from the same cities and found contrasting results. Despite infecting the same groups, cyclical epidemics of gonorrhoea did not occur because there is no immunity to re-infection with this disease. Change in the numbers of new gonorrhoea cases is therefore more likely to reflect change in sexual behaviour rather than the cyclical natural phenomenon seen with syphilis.

Dr Grassly, a Royal Society University Research Fellow, adds: "It is striking how the repeated epidemics of syphilis are predicted by what we know about the natural history of infection. As well as analysing previous epidemics it may also be possible to use these findings to help doctors and sexual health workers predict and prepare for future outbreaks of the disease. Troughs in the number of cases offer an unprecedented opportunity for eradication of the disease. However, when this opportunity is missed, an epidemic is likely to follow."

The researchers believe the role of population immunity highlights the need to carefully interpret data from routine surveillance studies, where changes in the rate of new infections may not always be attributable to changes in behaviour or the environment.

Tony Stephenson | EurekAlert!
Further information:
http://www.imperial.ac.uk

More articles from Health and Medicine:

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht On track to heal leukaemia
18.01.2017 | Universitätsspital Bern

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: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>