The BBC reports:

An experimental HIV vaccine has for the first time cut the risk of infection, researchers say. The vaccine – a combination of two earlier experimental vaccines – was given to 16,000 people in Thailand, in the largest ever such vaccine trial. Researchers found that it reduced by nearly a third the risk of contracting HIV, the virus that leads to Aids. Speaking at a news conference in Thailand, US ambassador to Thailand, Eric G. John, said the trial has “brought us one step closer to an HIV vaccine”.

Lib Dem shadow science minister Evan Harris has issued the following response:

The field of HIV vaccine research is littered with failures and disappointments. Ideas which look great on paper or in theory end up not giving protection against the virus in the real world. This is the first time that scientists have come close to making that leap, and it’s a real cause for hope.

“However, it would be premature to say this is a turning point. The study suggests that the vaccine showed effectiveness in just over 30% of people, but peer-reviewed publication and scientific analysis will be needed before we can judge whether and when this can be made available.

“The research raises many questions. Will the vaccine be specific to the Thai virus, or indeed to the Thai people? Are there ways to make it more effective? What delivery methods could improve the efficacy?

“This really gives me hope. I don’t think we’ll win the battle against HIV without a vaccine, and this is the first real sign we’ve had to show that such a vaccine is achievable.

“Politicians and scientists should take this as a cue to redouble their efforts into vaccine research, so that we can get a really effective vaccine out there to protect people. That would be a breakthrough.

“But even that won’t be a ‘magic bullet’ – in the meantime, we need to continue vital education programmes to explain how people can reduce their risk of contracting the virus through using condoms, being careful about sexual partners, amongst other measures.”