ðeɪ ɐplˈaɪd ðə mˈɛθədz ʌv tədˈeɪz dʒɪnˈɛɾɪks tʊ ˈoʊld pɹɪzˈɜːvd spˈɛsɪmənz fɹʌm ˈɔːtɑːpsiz ʌv pˈeɪʃənts wɪð ˌiːˌɛfˈiː dˈʌn wˈɛl bᵻfˌoːɹ mˈʌmps ˌɪmjuːnᵻzˈeɪʃən bɪɡˈæn ænd fˈaʊnd mˈʌmps dʒˈiːnoʊm ɪnðə tˈɪʃuːz ʌv ˌoʊvɚɹ ˈeɪɾi pɚsˈɛnt ʌv ðiːz pˈeɪʃənts.
They applied the methods of today's genetics to old preserved specimens from autopsies of patients with EFE done well before mumps immunization began and found mumps genome in the tissues of over 80% of these patients.