O1 Serovars Research Articles

Vibrio cholerae O1 (serovar inaba) as a cause of fatal bacteremia in a patient with relapsed acute lymphoblastic leukemia

O1 is an uncommon cause of bacteremia with only a few cases reported in published literature. We report a rare and fatal case and O1 serovar inaba bacteremia in a 29-year-old male patient on chemotherapy for relapsed and refractory B-cell acute lymphoblastic leukemia. He had no associated intestinal symptoms.

РАСПРОСТРАНЕННОСТЬ ICE ЭЛЕМЕНТОВ РАЗЛИЧНЫХ ТИПОВ У V. CHOLERAE

With the help of a virtual PCR in silico analysis of the local database 395 genome-nucleotide sequences of Vibrio cholerae in the presence of ICE element. The results showed widespread ICE member from toxigenic strains and nontoxigenic Vibrio cholerae O1 serotype. Thus all elements of ICE successfully typed three basic types – «Indian», «Mozambique», or «the SXT». In this case up to 40 % nontoxigenic strains O1 serovar and nonO1/nonO139 carried ICE element. When analyzed by PCR in vitro collection of 222 strains of Vibrio cholerae O1 serotype shows the presence of ICE element and determine its type in toxigenic strains isolated in recent years in the Russian Federation. All nontoxigenic O1, O139 and nonO1/nonO139 strains isolated in Russia, deprived of ICE element that differs from strains circulating in endemic cholera areas. This observation allows us to consider the presence of ICE element as a new epidemic marker «of invasive strains of» nontoxigenic Vibrio cholerae.

Comparison of histopathological*features of Vibrio cholerae O1 El Tor and*O139 Bengal infections in rabbit intestinal mucosa

AbstractVibrio cholerae is the causative agent of the infectious disease, cholera. The bacteria adhere to the mucosal membrane and release cholera toxin, leading to watery diarrhea. There are >100 serovars of V. cholerae, but the O1 and O139 serovars are the main causative agents of cholera. The present study aimed to compare the severity of intestinal mucosal infection caused by O1 El Tor and O139 V. cholerae in a rabbit ileal loop model.The results showed that although the fluid accumulation was similar in the loops inoculated with O1 and O139 V. cholerae, the presence of blood was detected only in the loops inoculated with the O139 serovar. Serosal hemorrhage was confirmed by histopathological examination and the loops inoculated with O139 showed massive destruction of villi and loss of intestinal glands.The submucosa and muscularis mucosa of the ileum showed the presence of edema with congested blood vessels, while severe hemorrhage was seen in the muscularis propria layer. The loops inoculated with O1 El Tor showed only minimal damage, with intact intestinal villi and glands. Diffuse colonies of the O139 serovar were seen to have infiltrated deep into the submucosal layer of the intestine. Although the infection caused by the O1 serovar was focal and invasive, it was more superficial than that due to O139, and involved only the villi. These observations were confirmed by immunostaining with O1 and O139 V. cholerae-specific monoclonal antibodies. The peroxidase reaction demonstrated involvement of tissues down to the submucosal layer in O139 V. cholerae infection, while in O1 El Tor infection, the reaction was confined mainly to the villi, and was greatly reduced in the submucosal region. This is the first reported study to clearly demonstrate the histopathological differences between infections caused by the O139 Bengal and O1 El Tor pathogenic serovars of V. cholerae (atif et al., 2009).

Comparison of histopathological*features of Vibrio cholerae O1 El Tor and*O139 Bengal infections in rabbit intestinal mucosa

Vibrio cholerae is the causative agent of the infectious disease, cholera. The bacteria adhere to the mucosal membrane and release cholera toxin, leading to watery diarrhea. There are >100 serovars of V. cholerae, but the O1 and O139 serovars are the main causative agents of cholera. The present study aimed to compare the severity of intestinal mucosal infection caused by O1 El Tor and O139 V. cholerae in a rabbit ileal loop model.The results showed that although the fluid accumulation was similar in the loops inoculated with O1 and O139 V. cholerae, the presence of blood was detected only in the loops inoculated with the O139 serovar. Serosal hemorrhage was confirmed by histopathological examination and the loops inoculated with O139 showed massive destruction of villi and loss of intestinal glands.The submucosa and muscularis mucosa of the ileum showed the presence of edema with congested blood vessels, while severe hemorrhage was seen in the muscularis propria layer. The loops inoculated with O1 El Tor showed only minimal damage, with intact intestinal villi and glands. Diffuse colonies of the O139 serovar were seen to have infiltrated deep into the submucosal layer of the intestine. Although the infection caused by the O1 serovar was focal and invasive, it was more superficial than that due to O139, and involved only the villi. These observations were confirmed by immunostaining with O1 and O139 V. cholerae-specific monoclonal antibodies. The peroxidase reaction demonstrated involvement of tissues down to the submucosal layer in O139 V. cholerae infection, while in O1 El Tor infection, the reaction was confined mainly to the villi, and was greatly reduced in the submucosal region. This is the first reported study to clearly demonstrate the histopathological differences between infections caused by the O139 Bengal and O1 El Tor pathogenic serovars of V. cholerae (atif et al., 2009).

Comparison of histopathological features of Vibrio cholerae O1 El Tor and O139 Bengal infections in rabbit intestinal mucosa.

Vibrio cholerae is the causative agent of the infectious disease, cholera. The bacteria adhere to the mucosal membrane and release cholera toxin, leading to watery diarrhea. There are >100 serovars of V. cholerae, but the O1 and O139 serovars are the main causative agents of cholera. The present study aimed to compare the severity of intestinal mucosal infection caused by O1 El Tor and O139 V. cholerae in a rabbit ileal loop model. The results showed that although the fluid accumulation was similar in the loops inoculated with O1 and O139 V. cholerae, the presence of blood was detected only in the loops inoculated with the O139 serovar. Serosal hemorrhage was confirmed by histopathological examination and the loops inoculated with O139 showed massive destruction of villi and loss of intestinal glands. The submucosa and muscularis mucosa of the ileum showed the presence of edema with congested blood vessels, while severe hemorrhage was seen in the muscularis propria layer. The loops inoculated with O1 El Tor showed only minimal damage, with intact intestinal villi and glands. Diffuse colonies of the O139 serovar were seen to have infiltrated deep into the submucosal layer of the intestine. Although the infection caused by the O1 serovar was focal and invasive, it was more superficial than that due to O139, and involved only the villi. These observations were confirmed by immunostaining with O1 and O139 V. cholerae-specific monoclonal antibodies. The peroxidase reaction demonstrated involvement of tissues down to the submucosal layer in O139 V. cholerae infection, while in O1 El Tor infection, the reaction was confined mainly to the villi, and was greatly reduced in the submucosal region. This is the first reported study to clearly demonstrate the histopathological differences between infections caused by the O139 Bengal and O1 El Tor pathogenic serovars of V. cholerae.

Influence of the copepod Mesocyclops longisetus (Crustacea: Cyclopidae) on the survival of Vibrio cholerae O1 in fresh water.

In an experimental microcosm, an analysis was performed of the influence exerted by freshwater Mesocyclops longisetus copepods on the survival of Vibrio cholerae O1 serovar Inaba. In the State of Ceará, copepods are used in the control of Aedes aegypti larvae. The system consisted of water with a salinity of 0.27 per 10,000 habitants and pH 7.5, which after sterilizing filtration was distributed into seven flasks with a volume of 400 ml; in each of six flasks, 10 live copepods were inoculated along with 1 ml of an 8-hour culture of Vibrio cholerae O1 at 37oC in Alkaline Peptone Water, resulting in a concentration of 3.80x10(4) colony-forming units. The control flask contained only the water with the same bacterial suspension. The system was maintained for six days at room temperature (25-28oC), and daily duplicate counts were performed in TCBS Agar. Results confirmed a clear association between Vibrio cholerae O1 and the live copepods, based on survival of the bacteria at compatible levels with the initial inoculation until the sixth day of the analysis.

Identification of Vibrio cholerae by enzyme electrophoresis

Zymovar analysis of 260 strains of Vibrio cholerae plus 3 reference strains of V. mimicus, using 13 structural loci, led to the grouping of strains in 73 zymovars (strain or group of strains sharing the same alleles). Effective separation of strains, distinction of V. cholerae strains from closely related V. mimicus and the detection of 2 vibrio strains, including one with two O1 serovars, in supposedly pure collection cultures, illustrate the potential of zymovar analysis in the identification of V. cholerae isolates. Two El Tor strains from USA, one CT+ and the other CT−, shared the same zymovar 71, while 127 typical El Tor strains belonged to zymovar 14.

Occurrence and characteristics of agglutination of Vibrio cholerae by serum from the eastern oyster, Crassostrea virginica

Cell-free hemolymph (serum) of the eastern oyster, Crassostrea virginica, agglutinated Vibrio cholerae, including all O1 serovars and biovars. Seventy-nine other strains of bacteria, including 14 genera and 26 species, were not agglutinated. The A, B, and C factors of O1 antigen were not involved in agglutination. Bacterial agglutinating (BA) activity was demonstrated for oysters inhabiting different environments of the U.S. Atlantic and Gulf coasts. Oyster serum BA titers showed high individual variation. The serum component(s) involved in BA was inhibited by 80 degrees C heat, pronase, EDTA, mucin, and fetuin treatments. N-Acetylneuraminic acid (10 mg/ml) weakly inhibited BA activity. Ligands of V. cholerae were sensitive to neuraminidase and resistant to 80 degrees C and pronase. High salinities (24 and 30%) enhanced BA. Cross-adsorption tests with V. cholerae and human O+ erythrocytes indicated that BA and hemagglutinating activities may involve different serum components. These results imply that the ecology of V. cholerae in C. virginica is influenced by agglutinating activity of oyster serum.

Isolation of O1 Serovars of Vibrio cholerae from Water by Serologically Specific Method

Vibrio cholerae bacteria of the serological variety O1 were consistently isolated from water samples by passing the water with added Tween 20 through columns packed with polystyrene beads coated with antibodies against the O1 antigenic determinants. The beads from the columns were washed, transferred to alkaline peptone broth, and incubated. The O1 serovars were isolated and identified by established procedures.