In the northern hemisphere Parv 4 DNA and Parv 4 antibodies are found mostly in IVDUs and others who are parenterally exposed. In Africa Parv 4 infection seems to be more widespread.
Á norðurhveli jarðar finnast Parv 4 DNA og mótefni gegn Parv 4 aðallega í sprautufíklum, en í Afríku virðist dreifing Parv 4 almennari.