GENITAL herpes, which can be life-threatening if passed to newborns, may soon be on the run thanks to a new vaccine against the herpes simplex virus. Clinical tests just completed show there are just a couple of catches. The vaccine doesn’t work for men, or for women who are infected with the related virus that causes cold sores.

In the US, genital herpes is reaching epidemic proportions with up to a fifth of the population estimated to be carrying the virus. Many infected people have no symptoms. But the virus can lie low in the body, causing recurrent outbreaks of genital blisters and fever. Genital herpes can also be passed from mother to baby during birth. When this happens it can cause blindness and life-threatening illness in the infant.

An international team organised by the drugs company SmithKline Beecham has developed a vaccine that gives women good protection against the …