Molecular epidemiology of tuberculosis in the Bata and Malabo districts of Equatorial Guinea.
METHODS
Bata and Malabo districts, Equatorial Guinea, 1 March 1999 to 28 February 2001.


OBJECTIVE
To study the molecular epidemiology of tuberculosis (TB).


RESULTS
During the study period, 429 patients were diagnosed with TB in the Bata and Malabo districts. A positive culture was obtained in 206 (48%) TB patients, with RFLP analysis being performed in 185 (89.8%). Ninety-two different patterns were identified. Single patterns were found in 71 strains (38.3%) and the remaining 114 strains (61.6%) were classified into 21 clusters (of 2 to 25 patients). In addition, 37 of the typing strains were resistant to one or more anti-tuberculosis drugs, and 30 were included in clusters (81%), with 21 low level isoniazid (MIC < or = 1 microg/ml) resistance strains in the same cluster. Statistical analysis showed that resistance to anti-tuberculosis drugs (OR 3.1; 95% CI 1.2-7.6; P = 0.014), and positive smear results (4+ grade smear) (OR 4.3; 95% CI 1.5-12; P = 0.005), were significantly more frequent among patients with clustered strains. No epidemiological links were related to clustering.


CONCLUSIONS
The level of clustering (61.6%) observed suggests a high degree of recent transmission and a predominance of determined patterns of Mycobacterium tuberculosis strains among the population of Equatorial Guinea.
Tudó
G
G
Servei de Microbiologia, Centre de Diagnòstic Biomèdic, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
González-Martín
J
J
Obama
R
R
Rodríguez
J M
JM
Franco
J R
JR
Espasa
M
M
Simarro
P P
PP
Escaramis
G
G
Ascaso
C
C
García
A
A
Jiménez De Anta
M T
MT
D000328:Adult; D016703:Equatorial Guinea / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000382:microbiology