I had to do the conversions but just so we are all on the same page, 40 C is 104 F and 60C is 140 F. So, in the USA, we are usually told to put our hot water heaters at 120F for safety reasons and to conserve energy. Therefore, if you are using hot at that temp, you are not killing all the germs by hot water alone. You may be drowning the dust mites and if you use bleach or some alternative you may be killing germs that way, but hot water alone is not killing anything as it is not hot enough. I believe the next setting on most hot water heaters is 150F. That would kill germs but would be considered scalding and a waste of energy and a safety hazard around small kids.
I do wash my whites on hot once in a while with a dash of real bleach because that it the only thing that keeps stink out of my front loader. But, mostly, I use warm or cold and bleach alternative if anything. I wash towels and sheets frequently to prevent yuck buildup and I give them an extra rinse sometimes.
If you want to kill germs in a warm or cold wash, you have to add a disinfectant. You can use oxygen bleach or vinegar. There are alternatives.
Here is a link about green laundryhttp://thegreenguide.com/doc/119/laundry
Here is a link about green ways to disinfecthttp://www.punkinbutt.com/soap_detergent.asp
Also, keep in mind that germ killing is overrated. Scientists are beginning to believe that the plethora of allergy problems is actually related to lack of germs in our environment, that our immune systems are reacting to allergens because they do not have experience with germs. So, antibacterials and germ killers may be creating allergy problems. Studies show that people who live on farms have the lowest incidence of allergies and the highest level of and variety of germs.