Transmission of InfectiousVibrio choleraethrough Drinking Water among the Household Contacts of Cholera Patients (CHoBI7 Trial).
Recurrent cholera causes significant morbidity and mortality among the growing population of Dhaka, the capital city of Bangladesh. Previous studies have demonstrated that household contacts of cholera patients are at >100 times higher risk of cholera during the week after the presentation of the index patient. Our prospective study investigated the mode of transmission ofVibrio cholerae, the cause of cholera, in the households of cholera patients in Dhaka city. Out of the total 420 rectal swab samples analyzed from 84 household contacts and 330 water samples collected from 33 households,V. choleraewas isolated from 20%(17/84) of household contacts, 18%(6/33) of stored drinking water, and 27%(9/33) of source water samples. Phenotypic and molecular analyses results confirmed theV. choleraeisolates to be toxigenic and belonging to serogroup O1 biotype El Tor (ET) possessing cholera toxin of classical biotype (altered ET). Phylogenetic analysis by pulsed-field gel electrophoresis (PFGE) showed theV. choleraeisolates to be clonally linked, as >95% similarity was confirmed by sub-clustering patterns in the PFGE (NotI)-based dendrogram. Mapping results showed cholera patients to be widely distributed across 25 police stations. The data suggesting the transmission of infectiousV. choleraewithin the household contacts of cholera patients through drinking water underscores the need for safe water to prevent spread of cholera and related deaths in Dhaka city.
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Raisa
R
Rafique
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Mahamud-Ur
MU
Rashid
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Shirajum
S
Monira
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Zillur
Z
Rahman
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Md Toslim
MT
Mahmud
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Munshi
M
Mustafiz
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
K M
KM
Saif-Ur-Rahman
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Fatema-Tuz
FT
Johura
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Saiful
S
Islam
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Tahmina
T
Parvin
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Md Sazzadul I
MS
Bhuyian
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Mohsena B
MB
Sharif
Department of Microbiology, Dhaka University Dhaka, Bangladesh.
Sabita R
SR
Rahman
Department of International Health, Johns Hopkins Bloomberg School of Public Health Baltimore, MD, USA.
David A
DA
Sack
Department of International Health, Johns Hopkins Bloomberg School of Public Health Baltimore, MD, USA.
R Bradley
RB
Sack
Department of International Health, Johns Hopkins Bloomberg School of Public Health Baltimore, MD, USA.
Christine M
CM
George
International Center for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
Munirul
M
Alam
Bangladesh; PFGE; Vibrio cholerae; cholera; clonal transmission; household contact