It is to be noted that contrary to the normal misconception that washing cloths manually or in the machine is not a process of killing microorganisms present on them. It can wash away certain level of micorganisms present. Microorganisms dislodge from cloths and washes away in the drain but some can stay for example in machine. If cloths for washing have obvious contamination (for example faecal contamination), it is advisable to remove that contamination manually before placing it in machine for wash. In normal circumstances, disinfection of machine with domestic bleach is sufficient. Pour a cup of fresh bleach prior to start of an empty wash cycle without a prior rinse is advisable to disinfect the machine. Also, see disinfection of cloths as in beddings.
Usually hot water from domestic water heaters is set around 60 degree Celsius which is sufficient to stop microbial multiplication (microbial static) whereas inactivation of microorganisms usually starts from 80 degree Celsius. It is worth noting that it does help to get the clothes cleaner by getting rid of potential hosts for bacteria. Hot water and detergent together attack oils and grime.