Interest of LQAS method in a survey of HTLV-I infection in Benin (West Africa).
HTLV-I is heterogeneously distributed in Sub-Saharan Africa. Traditional survey methods as cluster sampling could provide information for a country or region of interest. However, they cannot identify small areas with higher prevalences of infection to help in the health policy planning. Identification of such areas could be done by a Lot Quality Assurance Sampling (LQAS) method, which is currently used in industry to identify a poor performance in assembly lines. The LQAS method was used in Atacora (Northern Benin) between March and May 1998 to identify areas with a HTLV-I seroprevalence higher than 4%. Sixty-five subjects were randomly selected in each of 36 communes (lots) of this department. Lots were classified as unacceptable when the sample contained at least one positive subject. The LQAS method identified 25 (69.4 %) communes with a prevalence higher than 4%. Using stratified sampling theory, the overall HTLV-I seroprevalence was 4.5% (95% CI: 3.6-5.4%). These data show the interest of LQAS method application under field conditions to detect clusters of infection.
Houinato
Dismand
D
Institute of Neuroepidemiology and Tropical Neurology, School of Medicine, 2 rue du Dr Marcland, 87025 Limoges, France.
Preux
Pierre-Marie
PM
Charriere
Bénédicte
B
Massit
Bruno
B
Avodé
Gilbert
G
Denis
François
F
Dumas
Michel
M
Boutros-Toni
Fernand
F
Salamon
Roger
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001541:Benin / Q000453:epidemiology; D004812:Epidemiologic Methods; D005260:Female; D015490:HTLV-I Infections / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011785:Quality Assurance, Health Care / Q000379:methods*; D018401:Sample Size; D012494:Sampling Studies