I am not being pedantic but I am giving the up to date information from UK sources e.g. from uk babycentre website:
Before you first use new bottles and teats, and each time that you use them, they need to be washed and sterilised carefully. You will need a steam steriliser, or a microwave steriliser, or you can use sterilising solution. You can also boil the bottles and teats for at least 10 minutes to sterilise them.
All babies are vulnerable to the germs that cause diarrhoea and vomiting, and so it is best to continue sterilising bottles and teats (and breast pump equipment) until your baby is one year old and has built up more resistance to bacteria generally. The recommended age for starting solids is now six months, and bowls, plates and spoons can generally be cleaned using your usual washing-up method from this age.
From the department of health and food standards agency leaflet about bottle feeding:
Department of Health and Food Standards Agency revised guidance for health professionals on safe preparation, storage and handling of powdered infant formula (last modified 8th Feb 2007)
It is very important that all equipment used for feeding and preparing feeds has been thoroughly cleaned and sterilised before use.
? Wash hands thoroughly before cleaning and sterilising feeding equipment
? Wash feeding and preparation equipment thoroughly in hot soapy water
? Bottle and teat brushes should be used to scrub inside and outside of bottles and teats to ensure that all remaining feed is removed
? After washing feeding equipment rinse it thoroughly under the tap
? If using a commercial steriliser, follow manufacturer?s instructions
? If your bottles are suitable for sterilising by boiling: fill a large pan with water and completely submerge all feeding equipment, ensuring there are no air bubbles trapped; cover the pan and boil for at least 10 minutes, making sure the pan does not boil dry. Keep the pan covered until equipment is needed.
? Wash hands thoroughly and clean the surface around the steriliser before removing equipment.
? It is best to remove the bottles just before they are used.
? If the bottles are not being used immediately, they should be fully assembled with the teat and lid in place to prevent the inside of the sterilised bottle and the inside and outside of the teat from being contaminated.
As always, the guidelines on sterilsing vary from country to country but current UK guidelines are to continue to 1 year - you may or may not stick to that but that is the information given out.