There is little evidence that antibiotics prevent transmission outside of household settings, and side effects (especially gastrointestinal) are relatively common.Prophylaxis is aimed at preventing spread to infants.Treatment of contacts Antibiotic Prophylaxis: Notify all cases (suspected or confirmed) of pertussis to the Communicable Diseases Section, DHS, Victoria. Unimmunised or partially immunised children diagnosed with pertussis should still complete the pertussis immunisation schedule.Exclude from school and presence of others outside the home (especially infants and young children) until received 5 days of therapy, or coughing for more than 21 days.Trimethoprim-sulphamethoxazole (8-40 mg per mL).Azithromycin (for children = 6 months old): 10 mg/kg (max 500 mg) oral on day 1, then 5 mg/kg (max 250 mg) daily for 4 days.Clarithromycin liquid 7.5 mg/kg/dose (max 500 mg) oral BD for 7 days.Azithromycin 10 mg/kg oral daily for 5 days.Complications (pneumonia, cyanosis, apnoea).Cough for less than 14 days (may reduce spread reduces school exclusion period).
Diagnosed in catarrhal or early paroxysmal phase (may reduce severity).Pertussis serology (IgA) may be detectable 2 weeks after the onset of the illness but rarely affects clinical management.The test is usually negative after 21 days, or 5-7 days after effective antibiotic therapy has been commenced A nasopharyngeal aspirate/swab for PCR is the investigation of choice.Laboratory confirmation is not necessary for diagnosis, but may be helpful for infection control.Observation of coughing spasms may be helpful.Children are usually well between coughing spasms Other family members frequently have a cough (>70% of household contacts are also infected).Close contact with a case of Pertussis may raise suspicion.Infants may develop apnoea and/or cyanosis with coughing spasms.Vomiting often follows a coughing spasm.Pertussis can also present as a non-specific persistent cough.Classic whooping cough: Cough and coryza for one week (catarrhal phase), followed by a more pronounced cough in spells or paroxysms (paroxysmal phase).Patients are infectious just prior to and for 21 days after the onset of cough, if untreated.Can occur in immunised children but the illness is generally less severe.Infants less than 6 months of age are at greatest risk of complications (apnoea, severe pneumonia, encephalopathy) and are most commonly infected by spread from family members.Caused by the bacterium Bordetella pertussis (occasionally Bordetella parapertussis).