Great cormorants (Phalacrocorax carbo) as potential vectors for the dispersal of Vibrio cholerae

• Published in: Scientific reports Vol. 7; no. 1; pp. 7973 - 12
• Main Authors: Laviad -Shitrit, Sivan, Lev-Ari, Tidhar, Katzir, Gadi, Sharaby, Yehonatan, Izhaki, Ido, Halpern, Malka
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11-08-2017; Nature Publishing Group; Nature Portfolio
• Subjects: 45; 45/22; 45/23; 45/77; 631/326; 631/326/2565/855; Aquatic habitats; Birds; Cholera; Cholera toxin; Dispersal; Feces; Fish; Humanities and Social Sciences; Intestine; multidisciplinary; Pandemics; Pathogens; Phalacrocorax carbo; Prey; Science; Science (multidisciplinary); Toxins; Vibrio cholerae; Waterborne diseases
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-08434-8

Vibrio cholerae
is the cause of cholera, a devastating epidemic and pandemic disease. Despite its importance, the way of its global dissemination is unknown.
V
.
cholerae
is abundant in aquatic habitats and is known to be borne by copepods, chironomids and fishes. Our aim was to determine if fish-eating birds act as vectors in the spread of
V
.
cholerae
by consuming infected fish. We determined the existence of
V
.
cholerae
in the microbiome of 5/7 wild cormorants’ intestine. In three of these
V
.
cholerae
-positive wild cormorants, the presence of a gene for cholera toxin (
ctxA
) was detected. We subsequently tested eight captive, hand-reared cormorants, divided into two equal groups. Prior to the experiment, the feces of the cormorants were
V
.
cholerae
-negative. One group was fed exclusively on tilapias, which are naturally infected with
V
.
cholerae
, and the other was fed exclusively on goldfish or on koi that were
V
.
cholerae
-negative. We detected
V
.
cholerae
in the feces of the tilapia-fed, but not in the goldfish/koi-fed, cormorants. Hence, we demonstrate that fish-eating birds can be infected with
V
.
cholerae
from their fish prey. The large-scale movements of many fish-eating birds provide a potential mechanism for the global distribution of
V
.
cholerae
.