An outbreak of melioidosis, caused by a soil bacterium, has been reported from the Northern Territory. Travelers are advised to wear waterproof gloves and shoes or boots whenever coming into contact with soil in this area, especially during the rainy season.
Prognosis
Without access to appropriate antibiotics (principally ceftazidime or meropenem), the septicemic form of melioidosis has a mortality rate that exceeds 90%. With appropriate antibiotics, the mortality rate is about 10% for uncomplicated cases but up to 80% for cases with bacteraemia or severe sepsis. Response to appropriate antibiotic treatment is slow with the average duration of fever following treatment being 5–9 days.
Recurrence occurs in 10 to 20% of patients. While molecular studies have established that the majority of recurrences are due to the original infecting strain, a significant proportion of recurrences (perhaps up to a quarter) in endemic areas may be due to reinfection, particularly after 2 years. Risk factors include severity of disease (patients with positive blood cultures or multifocal disease have a higher risk of relapse), choice of antibiotic for eradication therapy (doxycycline monotherapy and fluoroquinolone therapy are not as effective), poor compliance with eradication therapy and duration of eradication therapy less than 8 weeks.
Prevention
Person-to-person transmission is exceedingly unusual; and patients with melioidosis should not be considered contagious. In endemic areas, people (rice-paddy farmers in particular) are warned to avoid contact with soil, mud and surface water where possible. Case clusters have been described following flooding and cyclones and probably relate to exposure. Other case clusters have related to contamination of drinking water supplies. Populations