According to new research in the Archives of Internal Medicine consistent condom use can reduce the risk of genital herpes by 30%.

Study lead author Dr. Emily T. Martin of Children's Hospital Research Institute and the University of Washington, Seattle said, "Condoms work for herpes. It's the consistent use of the condom that's important."

Causing genital herpes, the herpes simplex virus 2 (HSV-2) is a chronic, lifelong viral infection that can cause painful sores in the genital area. The researchers said previous studies have found regular condom use to reduce the spread of HIV and other sexually transmitted diseases (STDs) such as Chlamydia and gonorrhea.

However the benefit in preventing the transmission of HSV-2 has been less certain.

"Even though the decrease is smaller than you would see with some other STDs, the evidence from previous studies has been unclear whether using a condom to prevent getting herpes was going to be effective, but this shows that it is," Martin said.

In the study published in the July 13 issue of Archives of Internal Medicine, researchers looked at data from six HSV-2 studies that dealt with the effectiveness of condoms in preventing herpes and included 5,384 men and women who did not have herpes when the studies began.

The follow up period ranged from 12 to 19 months and during this 415 contracted genital herpes. In the case of people who reported using a condom 100% of the time, the risk was found to be 30% less of contracting the virus than the people who did not use condoms.

Martin and her team found the risk of becoming infected rose steadily with the number of unprotected sex acts and there was no significant difference between men and women in the effectiveness of condoms in preventing herpes transmission.

The researchers said that the risk of getting herpes was reduced 7 % "every additional 25 %of the time that condoms were used during anal or vaginal sex."

Herpes transmission is only reduced by 30% as unlike other STDs, herpes is transmitted by skin-to-skin contact explained Martin. "Transmission has a lot to do with where the virus is being shed at the time," she said. "If someone with herpes is shedding virus for an area that is not covered by a condom, we speculate the virus will spread whether or not they are using a condom."

Martin said, "30 percent is partial protection, but its protection."

Dr. Jeffrey D. Klausner, director of STD Prevention and Control Services at the San Francisco Department of Public Health said "We know condoms can prevent the spread of sexually transmitted infections like HIV, herpes, warts, hepatitis, gonorrhea, Chlamydia and syphilis, but it's always been hard to show that in research studies."

Klausner said that the study provides scientific evidence that condoms work and should help in efforts to get condoms to sexually active teenagers and adults.