Para pertussis in infants: what parents should know

Para pertussis refers to illness caused by a parainfluenza virus, while pertussis is whooping cough caused by a bacterium. The names can sound similar, but they are different infections. In a young baby, cough may be mild at first or may appear with pauses in breathing, poor feeding, vomiting after coughing, unusual sleepiness or a change in skin colour. A cough can be dry or bring up mucus; see the guide to [Cough](/symptoms/cough/), and check [Fever](/symptoms/fever/) if the baby feels hot.

A clinician may listen to the chest, check breathing and oxygen levels, and decide whether testing or observation is needed. The illness may resemble [Whooping Cough](/conditions/whooping-cough/), so do not rely on the sound of the cough to identify its cause.

Arrange same-day advice for an infant with a new or worsening cough. Keep the baby upright while awake, offer usual feeds in small frequent amounts if feeding is difficult, and keep the air free from smoke and strong fragrances. Record when coughing spells occur, whether breathing pauses happen, and how much the baby is feeding and wetting nappies.

Do not give over-the-counter cough medicines or leftover antibiotics unless a clinician specifically recommends them. Antibiotics may be considered when bacterial pertussis is suspected; read about [Antibiotic Treatment](/treatments/medical-management/antibiotic-treatment/). Discuss protection for the baby and close contacts through [Childhood Immunisation](/treatments/preventive-care-and-vaccination/childhood-immunisation/).

Seek emergency help if the baby struggles to breathe, has repeated pauses in breathing, turns blue or grey around the lips, cannot feed, becomes difficult to wake, or has markedly fewer wet nappies. A choking-looking coughing spell, limpness or a sudden deterioration also needs urgent assessment. Keep the baby away from other children while arranging care and tell the service about possible exposure to a contagious cough.

Ask whether the symptoms fit a viral illness, pertussis or another cause; whether testing is needed; how to support feeds and sleep; which breathing changes require emergency help; and whether household members need assessment, treatment or vaccination advice.