Diagnosis of Neonatal Listeriosis Culture or polymerase chain reaction (PCR) testing of blood, cervix, and amniotic fluid (if available) of febrile pregnant woman Culture or PCR of blood, cerebrospinal fluid (CSF), gastric aspirate, meconium, and infected tissues of sick neonate Blood and cervix specimens should be obtained from any pregnant woman with an unexplained febrile disease and cultured or PCR tested for L monocytogenes.