Fifty million screening tests are performed for tuberculosis each year, but Oxford Immunotec claims that the established diagnosis method is inefficient and unreliable. It says its lead product T-SPOT saves time and is more accurate. This University of Oxford spin-out was co-founded by Dr Peter Wrighton-Smith and Professor Ajit Lalvani in 2002, and sales increased 59% a year from £2m in 2008 to £8m in 2011. In June, Imperial Innovations and Invesco Perpetual led an £18.2m funding round, which will be used for global marketing.