Neonatal sepsis may be a sort of neonatal infection and specifically refers to the presence during a neonate of bacterial bloodstream infection (BSI) (such as meningitis, pneumonia, pyelonephritis, or gastroenteritis) in the setting of fever. Older textbooks may ask neonatal sepsis as "sepsis neonatorum". Criteria with regards to hemodynamic compromise or respiratory failure aren't useful clinically because these symptoms often don't arise in neonates until death is imminent and unpreventable. Neonatal sepsis is split into two categories: early-onset sepsis (EOS) and late-onset sepsis (LOS). EOS refers to sepsis presenting within the first 7 days of life (although some ask EOS as within the primary 72 hours of life), with LOS pertaining to the presentation of sepsis after 7 days (or 72 hours, counting on the system used). Neonatal sepsis is that the single commonest explanation for death in the hospital also as a community in developing countries.