Haemophilus Influenzae Type B Disease And Vaccination: Asia
Invasive Haemophilus influenzae type b (Hib) disease is a major cause of morbidity and mortality among infants and young children throughout the world. It is the most frequent etiologic agent of bacterial meningitis in Thai infants, accounting for 42 to 44% of total cases,1-3 and can cause bacteremia, pneumonia and septic arthritis. In contrast epiglottitis is a rare clinical entity without any clear explanation among this region of the world.3
The absolute incidence of Hib disease is not known, but the existent problems are common among young infants. Many authorities claim that the incidence of Hib disease may be lower in Thailand than in most developed countries because of the different epidemiology of disease and probably because of extensive abuse of antibiotics in this country. The peak age incidence of Hib meningitis in Thailand is ∼5 to 6 months, whereas it is 9 months in most developed countries.4 The younger age incidence of Hib disease might affect the efficacy of vaccine, a question that needs further evaluation.5
Recently a retrospective study was performed to define the burden of invasive Hib disease in Thailand. The estimated annual incidence of Hib disease, as determined by this study, was 5.8 per 100 000 children younger than age 5.6 Unfortunately this figure was calculated from hospital-based data.
Hib vaccine was introduced to Thailand as an optional vaccine several years ago, with a rather high price compared with other vaccines. It will be necessary to evaluate further the burden of Hib disease and the cost effectiveness of vaccine in Thailand before recommending nationwide Hib vaccination in the EPI program.
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2. Yuengsrigul A, Lolekha S. Acute bacterial meningitis in children [in Thai, with English Abstract]. Thai J Pediatr 1991;30:116-20.
3. Sirinavin S. Regional epidemiology of invasive Haemophilus influenzae
type b disease. JAMA SEA 1993;(Suppl):S11-5.
4. Bijlmer HA. Worldwide epidemiology of Haemophilus influenzae
meningitis; industrialized versus
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5. Makela PH, Takala AK, Peltola H, et al. Epidemiology of invasive Haemophilus influenzae
type b disease. J Infect Dis 1992;165(Suppl 1):S2-6.
6. Sunakorn P. Current situation of Haemophilus influenzae
b diseases in Thailand
[in Thai, with English Abstract]. Com Dis J 1996;22:361-7.
FIRST INTERNATIONAL CONFERENCE ON HAEMOPHILUS INFLUENZAE TYPE b INFECTION IN ASIA
The Editors thank the Association pur l'Aide à la Médicine Préventive, the Foundation Mérieux, and the World Health Organization for supporting publication of these proceedsings, and Jennifer Wells for her editorial assistance.