In one of the most highly publicised statements, in October 2003, the President of the Vatican's Pontifical Council for the Family, Cardinal Alfonso Lopez Trujillo, said: "The AIDS virus is roughly 450 times smaller than the spermatozoon.
The spermatozoon can easily pass through the 'net' that is formed by the condom.
These margins of uncertainty...should represent an obligation on the part of the health ministries and all these campaigns to act in the same way as they do with regard to cigarettes, which they state to be a danger." Finding out the degree to which condoms protect against HIV is important both for HIV-negative people who want to protect themselves against HIV, and HIV-positive people who want to avoid transmitting it.
Knowing how well they protect against other STIs is important for sexual health in general and may be particularly important for people with HIV, who may be more vulnerable to the effects of certain STIs.
The main findings of studies we look at in more detail below are as follows: These degrees of protection may be lower than some readers expect, and rates of 98% reliability are still sometimes quoted for condoms.
Thirdly, in long-term serodiscordant relationships, studies have shown that the HIV-negative partner can acquire a degree of immunity to their partner’s HIV.Studies of condom efficacy have therefore largely contrasted HIV and STI incidence or prevalence in people who claim 100% consistent use against people who use them inconsistently or not at all.Because these studies involve private behaviours that investigators cannot observe directly, it is difficult to determine accurately whether an individual is a condom user and whether condoms are used consistently and correctly.Moral questions about condom use are not within the remit of this resource, but questions of fact are, and condoms’ ability to stop HIV is periodically questioned by people opposed to their use on religious or moral grounds.Therefore questions of condom efficacy have to be addressed and misapprehensions corrected.One widely quoted remark of this nature came from Ugandan President Yoweri Museveni who, at the Fifteenth International AIDS Conference in Bangkok in 2004, advocated for HIV prevention based on “optimal relationships based on love and trust instead of institutionalised mistrust, which is what the condom is all about…I think of condoms as an improvisation, not a solution”.(See the text of Museveni’s speech.) Museveni later complained of being misunderstood and signed an article in The Lancet saying that condoms formed a valuable part of HIV prevention.Despite this, the use and promotion of condoms continue to be targets for controversy and criticism, and sexual abstinence and monogamy are often promoted as superior alternatives.While condoms offer useful and vital protection, they have also become associated with promiscuity and infidelity.Research early on in the epidemic showed that 40 to 70% of men who claimed they use condoms 100% of the time in fact did not use them for every act of intercourse.Twenty years later, 51 to 66% of women taking part in a microbicide study reported 100% condom usage at different time points during the trial, but the researchers calculated from inconsistency in their answers that the actual proportion who maintained 100% condom use was 25%.