Distribution of potentially pathogenic bacteria as free living and plankton associated in a marine coastal zone

Abstract

Aims: To determine the abundance of faecal and nonfaecal bacteria related to human and animal health, as free living or associated with small (>64 lm) and large (>200 lm) plankton, samples were collected monthly from the coastal zone at Messina (Italy). Methods and Results: Different enrichment and selective cultural methods were used to determine the abundance of bacteria in sea water and plankton. The bacteria were more frequently isolated from water and large plankton than from small plankton. Vibrio and Aeromonas spp. showed different distribution patterns in water and plankton. Faecal indicators were always present in water and the large size class plankton samples. Enterococci associated with large plankton were more abundant than E. coli in the winter. Vibrio species distributions were different in water and plankton samples. Among arcobacters only A. butzleri was isolated from water and plankton samples. Campylobacter spp. was always absent in small plankton and more frequent in large plankton than in water. Conclusions: The colonization of zooplankton by potentially pathogenic bacteria is a widespread phenomenon. Significance and Impact of the Study: The presence of potentially pathogenic bacteria in sea water and associated with plankton can have ecological and epidemiological implications.

VIBRIO AND PHYTOPLANKTON DYNAMICS DURING THE SUMMER OF 2004 IN A EUTROPHYING ESTUARY

“…Vibrio parahaemolyticus is less deadly, but causes a greater number of food-borne illnesses and can result in pandemic outbreaks of disease (Mead et al 1999, Strom and Paranjpye 2000, Wong et al 2000. Vibrio cholerae remains a major threat in many places around the globe as the causative agent of cholera, and its reservoir in the estuarine environment may play an important role in the survival and transport of pathogenic strains , Chakraborty et al 2000, Binsztein et al 2004 Previous studies have demonstrated strong relationships between Vibrio abundance and environmental conditions such as salinity, temperature, and attachment to planktonic organisms (Tamplin et al 1990, Heidelberg et al 2002, Lipp et al 2003, Louis et al 2003, Maugeri et al 2004. Harsh conditions, most often low temperature for Vibrio sp., stimulate a change in populations to a viable, but non-culturable (VBNC) state , Binsztein et al 2004.…”

Temporal Evolution of the Microbiological Conditions of a Sicilian Area Designed for Aquaculture (Castellammare Gulf, Southern Tyrrhenian Sea)

“…Several studies [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] highlighted that the abundance of vibrios is often unrelated to that of faecal pollution indicators; therefore a complete assessment of the hygienic-sanitary quality of coastal waters should include these microorganisms to get a complete picture of the health risks associated to diseases from contaminated seafood. Halophilic vibrios are microorganisms autochthonous of marine environments; their abundance follows a seasonal trend, increasing during summer months [27]; moreover, coastal and estuarine habitats rich in organic polymers are typical habitats for vibrios whose growth depends on the availability of organic matter [11].…”

“…The enumeration of faecal coliforms is the first criterion to be satisfied to meet both environmental protection and human health. In addition, bacterial pathogens which are recognized as responsible for the outbreaks of intestinal diseases such as Vibrios, some of which are natural inhabitants of marine environments (Vibrio cholerae, V. parahaemoluticus) [11,12] require further attention, since these bacteria may constitute a potential health hazard, even if not under the above cited legislation [13][14][15][16][17].…”

“…It is a wide bay about 70 Km long, comprised between Capo S. Vito and Terrasini, characterized by the presence of extensive mussel beds and by the outflows of alcohol distilleries which enrich waters with organic substrates; also stream inflows cause a persistent turbidity of waters, which have sporadically undergone to eutrophication. In spite of the great potentiality of the Gulf for aquaculture and fish farming, information on the microbiological conditions of the Gulf is still fragmentary; to our knowledge, only a few scientific reports are available [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22].…”

Arcobacter

“…Arcobacter has been isolated from seawater and marine shellfish (see 1.3.2.5 and references therein), including A. butzleri that may be associated with plankton Maugeri et al, 2004). Other reports have identified all three human infectious species A. butzleri, A. cryaerophilus and A. skirrowii from seawater .…”