Background: Because of the possible presence of small holes, the effectiveness of condoms as barriers to virus transmission is controversial.
Goals: To determine the proportion of condoms that allow virus penetration and the amounts of virus that penetrate.
Study design: A sensitive, static test was used to evaluate different condom types as barriers to a small virus, including brand with or without lubrication and ones of different materials. The test included some physiologic-based parameters and some parameters that exaggerated expected actual use conditions.
Results: Under test conditions, 2.6% (12 of 470) of the latex condoms allowed some virus penetration; the median level of penetration was 7 x 10(-4) ml. Lubricated condoms performed similarly to nonlubricated ones. Polyurethane condoms yielded results higher than but not statistically different from those for latex condoms.
Conclusions: Few condoms allowed any virus penetration. The median amount of penetration for latex condoms when extrapolated to expected actual use conditions was 1 x 10(-5) ml (volume of semen). Thus, even for the few condoms that do allow virus penetration, the typical level of exposure to semen would be several orders of magnitude lower than for no condom at all.
PIP: Nine brands and 470 samples of latex condoms and two brands and 76 samples of polyurethane condoms bought from retail distributors were tested in vitro for their ability to block the penetration of virus. A sensitive, static test apparatus was designed for and used in the evaluation. The test included some physiological-based parameters as well as some which exaggerated the expected actual use conditions. Both lubricated and nonlubricated condoms were tested. Before testing, however, most of the lubrication was removed from the lubricated condoms through rinsing with Dulbecco's phosphate-buffered saline and blotting with sterile paper towels. The 0X174 bacteriophage of 27 nm particle diameter, 32 nm including its bulky spikes, was used as the proxy challenge virus. Under test conditions, 12 of the latex condoms (2.6%) allowed some virus penetration of median quantity 0.0007 ml. Just two of the latex condoms were responsible for 99.8% of the total penetration among latex condoms overall. The performance of lubricated condoms was similar to that of nonlubricated ones. Four of the polyurethane condoms allowed penetration, but only one condom was responsible for 98.6% of total penetration. The difference in performance between latex and polyurethane condoms is not statistically significant. The median amount of penetration for latex condoms when extrapolated to expected actual use conditions was 0.00001 ml of semen. Therefore, even for the few condoms which allow virus penetration, the typical level of exposure to semen is several orders of magnitude lower than the amount of exposure expected when not using a condom.