Valentine's Day is a celebration of romance and love, yet it also has significant connections with medical discoveries.

On February 14, 1929, a Professor of Bacteriology at St. Mary's Hospital in London, introduced a mould by-product called penicillin.

Vice-President of Medical Services for Southern Health-Santé Sud, Dr. Denis Fortier, says penicillin is one of the most unprecedented advances in medicine, and before its discovery doctors couldn't treat infections.

"They knew that bacteria played a role in certain illnesses and they knew about prevention in terms of good hygiene and surgeons washing their hands before surgery. They came to understand that if you reduced the number of bacteria in certain situations, you could reduce infections."

Arriving home from vacation on September 3, 1928, Sir Alexander Fleming observed one of the Petri dishes he had left out containing Staphylococcus bacteria was dotted with colonies except for an area covered in mould. This mould was a rare strain of Penicillium notatum. Fleming eventually discovered the solution produced by the fungus could kill or inhibit other microbial species, the discovery of this would lead to the antibiotic known as penicillin.

Initially, the production of antibiotics was from moulds Fortier says, and after World War Two drug companies were seeing the value of mass producing this product and would look to molecules for production, instead of cultivating moulds.

Fortier says today penicillin and antibiotics are widely used and are incredibly important in the field of medicine. However, the liberal usage of them has created some unforeseen consequences.

"We've seen resistance to the molecule grow through the world, we're facing the concerns of antibiotic-resistant bugs, and we have to figure that one out as well. It's a great molecule, but it's been perhaps used a bit much in the last 60 years."

Penicillin has shaped the medical world as we know it, but Fortier says the next significant advancement in medicine will be understanding this resistant bacteria, and to manipulate the molecule or bacteria to make them once again susceptible to antibiotics.