Treatment, Prevention and Control of Haemophilus influenza Infections

Treatment

Antibiotics are the mainstay of treatment of H. influenzae infections. H. influenzae is susceptible to sulfonamides, chlor-amphenicol, ciprofloxacin, ampicillin, cefotaxime, and ceftazi-dime. Cefotaxime and ceftriaxone are the initial drugs of choice of treatment of Hib meningitis. These antibiotics given paren-terally to patients with uncomplicated meningitis for 7–14 days are effective. Penicillins are useful in the management of muco-sal infections caused by nonencapsulated H. influenzae. As many as 25–50% of isolates produce beta-lactamase; therefore, they are resistant to this class of drugs. Beta-lactamase-producing oral antibiotics, with activity against H. influenzae, include tri-methoprim–sulfamethoxazole, cefuroxime axetil, cefixime, clarithromycin, azithromycin, and ciprofloxacin. These drugs are given for 10 days in cases of otitis media and for at least 14 days for sinusitis.

Prevention and Control

◗ Vaccination

The Hib conjugate vaccine, now routinely given to infants and children, is highly effective. The vaccine has dramatically reduced the prevalence of invasive Hib disease. The vaccine elic-its a protective antibody response and prevents Hib disease by reducing pharyngeal colonization with Hib. The Hib conjugate vaccine, however, is not effective against disease caused by non-typable H. influenzae.

Originally, the Hib vaccine was an unconjugated polysac-charide vaccine, which consisted of the purified PRP capsu-lar polysaccharide. This vaccine, however, was not effective because it induced a poor immune response, did not protect children fully, and did not provide any antibody protection for infants. This therefore led to the development of the con-jugate Hib vaccines in which PRP is covalently linked to a protein.

◗ Chemoprophylaxis

Chemoprophylaxis by rifampin is used to reduce the coloniza-tion of Hib disease in children with high risk. Such high-risk group includes children below 2 years in a family or daycare centre where systemic disease is reported.