First Documented: 1884
Illness Caused: Sore Throat, Skin disorders
Antibiotic Resistance: Low
Like other potentially dangerous bacteria such as E.coli, Streptococcus pyogenes can be found in 5 per cent - 15 per cent of all humans, residing in the lungs or throat without causing any harm. Streptococcus pyogenes causes over 700 million infections globally every year and has a high mortality rate of 25 per cent in serious cases - once you have an infection the bacteria can cause a range of diseases ranging from sore throat and impetigo up to scarlet fever. Luckily, the bacteria is affected by penicillin so is treated easily in most cases - however several strains are building resistance to various other antibiotics.