Association of Vibrio cholerae with plankton in coastal areas of Mexico

Abstract

The El Niño event of 1997/1998 provided an opportunity to carry out a field experiment in which the relationship of sea surface temperature and the association of Vibrio cholerae with marine plankton could be assessed in Mexican coastal and estuarine areas. Plankton samples were collected from May 1997 through June 1999. Sites included the Mexican ports of Veracruz, Coatzacoalcos and Frontera in the Gulf of Mexico and Ensenada, Guaymas, Mazatlán, Manzanillo, Acapulco and Oaxaca in the Pacific Ocean. Sampling was also accomplished during two oceanographic cruises in the Yucatan channel of the Caribbean Sea. Bacteriological analyses for V. cholerae serogroups O1 and O139 were carried out. Also, the taxonomic structure of the plankton populations was determined. Vibrio cholerae O1 was detected only in Veracruz samples collected during April, May and June 1999, when La Niña climatic conditions prevailed. It is concluded that V. cholerae O1 in Mexico derives from its marine and estuarine origin and not from sewage contamination. The significant number of Acartia tonsa copepodites and V. cholerae copepodite-positive samples suggests a significant role of this copepod in the occurrence and distribution of V. cholerae in coastal areas of Mexico.

Interactions ofVibriospp. with Zooplankton

“…tonsa was shown to harbor VBNC V. cholerae in estuarine and marine regions in Argentina (68), and these VBNC cells reverted to the pathogenic state under favorable conditions. In estuarine and coastal regions in Mexico, V. cholerae O1 but not O139 strains were positively correlated with A. tonsa (65). Interestingly, V. cholerae was not detected in sewage but only in samples from sewage free environments, supporting the suggestion that natural nonpolluted water is the environmental reservoir of V. cholerae (69).…”

“…These copepods were the dominant species in Chesapeake Bay (67) and were abundant in the Bay of Bengal. Other studies have shown that V. cholerae is often associated with A. tonsa (19,65,68). Although these two copepods both belong to the order Calanoida they have different life cycles and physical properties.…”

“…In recent years, studies have shown that even in areas where cholera appears sporadically, or in areas where there is no history of cholera epidemics, V. cholerae is a natural component of the microbiota (64,65,66). In a large-scale study of bacteria attached to zooplankters in Chesapeake Bay, Heidelberg et al (43) found that V. cholerae, V. mimicus, and V. vulnificus comprised the largest fraction of attached Vibrio and Photobacterium species.…”

Phenotypic and genetic characteristics of Vibrio cholerae O1 carrying Haitian ctxB and attributes of classical and El Tor biotypes isolated from Silvassa, India

“…This observation is interesting because the classical biotype caused the sixth pandemic before being replaced by the El Tor biotype, which is considered extinct. It was noted that altered El Tor strains replaced the prototype of the seventh pandemic El Tor in Asia (Evins et al, 1995;Nair et al, 2002) and Africa (Lizarraga-Partida et al, 2009;Morita et al, 2008). However, the Haitian ctxB variant of V. cholerae was reported to cause epidemics in Asia and Africa (Bhattacharya et al, 2016;Goel et al, 2008;Naha et al, 2012;Rashed et al, 2012;Talkington et al, 2011).…”

Cholera between 1991 and 1997 in Mexico Was Associated with Infection by Classical, El Tor, and El Tor Variants of Vibrio cholerae

“…Biotype CL caused the first six of the seven cholera pandemics recorded between 1817 and 1923 (26), with five of these affecting the American continents. Ever since the first cases were detected in the Americas in the 1830s, endemic cholera continued to be prevalent until 1895 (18).…”