New Delhi, Aug 16 (TIWN): A vaccine to protect people against the common sexually transmitted infection chlamydia has passed initial safety tests.

It is the first of its kind to enter human trials.

Experts say immunisation may be the best way to tackle the disease that accounts for nearly half of all sex infections diagnosed in the UK.

More trials must check how well it works and what dose to give, The Lancet Infectious Diseases journal says.