Haemophilus aegypticus

Haemophilus aegypticus (Haemophilus influenzae biogroup aegyptius), a species of the genus Haemophilus in the family Pasteurellaceae, is an immotile, Gram-negative, coccoid rod bacterium.

H. aegypticus causes various local as well as systemic disease symptoms in the warm subtropical regions. Proven cases of the disease (Brazilian purple fever, contagious conjunctivitis) occurred in North Africa and Brazil.

Contagious conjunctivitis: In North Africa, Haemophilus aegypticus leads to self-limiting contagious conjunctivitis. In Brazil, Haemophilus aegypticus led to the clinical picture of "Brazilian purple fever" in children (<10 years). Brazilian purple fever (BPF) is a life-threatening pediatric infection preceded by conjunctivitis and caused by Haemophilus influenzae biogroup aegyptius. BPF was first detected in the state of Sao Paulo in 1984 and later (1990) in Mato Grosso. In 1990, six (60%) of 10 children who became ill died. In a subsequent outbreak (1992), children with BPF were found to have bacteremia caused by Haemophilus influenzae biogroup aegyptius (H. aegyptius). Molecular characterization of blood and other isolates revealed the clonal nature of the H. aegyptius strains that caused BPF. They were genetically distinct from the various strains causing only conjunctivitis. The virulence factors involved could not be definitively identified. After a series of outbreaks and sporadic cases until 1993, no further cases of BPF were reported (Harrison LH et al.2008).

1. Brazilian Purpuric Fever Study Group (1992) Brazilian purpuric fever identified in a new region of Brazil. The Brazilian Purpuric Fever Study Group. J Infect Dis165 Suppl 1:16-19.
2. Harrison LH et al.(2008) Emergence and disappearance of a virulent clone of Haemophilus influenzae biogroup aegyptius, cause of Brazilian purpuric fever. Clin Microbiol Rev 21:594-605.