Bacteria in Infant Formula - the risks and the solution

Powdered infant formula is known to be not sterile and is known to contain live bacteria, including salmonella, enterobacter sakazakii and E-coli, which is why the guidelines for making up formula safely say it should be made up with water at about 70 degrees and then allowed to cool before giving to baby - the temperature of the water will kill much of the bacteria.

Sterilising is the most effective way of protecting your baby from harmful germs and bacteria which can grow in the bottles and teats or on the implements used to prepare baby's infant formula.

If you are not exclusively breastfeeding then it is essential that all your baby's feeding equipment (such as bottles, caps, teats and any implements used for storing or measuring the powdered infant formula) should be sterilised until your baby is at least six months old, though ideally until 12 months old or if later as a baby's immune system becomes more resistant to germs after the age of 12 months. Cups and mugs need only be sterilised for six months, and after this time they just require careful cleaning. Ideally bottles need to continue to be sterilised until the child stops using bottles as the teats (and this applies to the valves of non-spill sippy cups, too) can have areas which are very hard to clean, and even a tiny amount of milk left inside can contain bacteria which can soon multiply and grow.

You can either use a commercial steriliser (ensure you follow the manufacturer's instructions - whether microwave sterilising, or using a steam steriliser), or use eg milton and water in a deep sided container - so-called cold water sterilising, or by boiling.

Here is a step-by-step guide to cleaning and sterilising your baby's feeding equipment