Decontamination after exposure, even briefly, to a parvo infected animal can only be assuredly attained with the use of bleach. Despite claims of products that are heavily promoted by perhaps less than ethical sales, this is a virus that is particularly hardy. Please carefully read the information at this site for the science (not a product) http://www.marvistavet.com/html/body_the_parvo_virus_in_the_environ.html
Outdoor decontamination is effected when there is a hard freeze and thaw. Without a freeze, shaded areas of lawn/land may take 7 months or longer to decontaminate; areas with sunlight, about 5 or 6 months. Constant watering is believed to speed up decontamination by diluting the virus, but even with daily soakings it would be wise to wait more than a month.
Inside the home, daily vaccuming of the carpet, washing of any and all surfaces encountered by the infected animal and bleach disinfecting of whatever areas will tolerate bleach is necessary, also for at least a month.