Non-O1, non-O139 Vibrio cholerae bacteremic skin and soft tissue infections

Antimicrobial susceptibility and genomic characterization of Vibrio cholerae non-O1/non-O139 isolated from clinical and environmental samples in Jiaxing City, China

Non-O1/non-O139 (NOVC) strains inhabit aquatic environments and sporadically induce human illnesses. This study involved the virulence and antimicrobial genetic characterization of 176 NOVC strains, comprising 25 from clinical samples and 151 from environmental sources, collected between 2021 and 2023. The antimicrobial susceptibility of the examined NOVC population was predominantly high, exhibiting only poor susceptibility to colistin, with 89.2% resistance. The examination of virulence genes revealed that the majority of strains were positive for glucose metabolism (als gene) (169/176, 96.0%). Through multilocus sequence typing, the 176 NOVC strains were categorised into 121 sequence types, 79 of which were novel. NOVC strains demonstrate significant genetic variability and frequently engage in recombination. This work offers genetic characterization of the pathogenicity and antimicrobial resistance of a NOVC community. Our findings offer insights that may aid in the development of preventative and treatment methods for this pathogen.

Vibrio cholerae Skin and Soft Tissue Infection Complicated by Sepsis in an Immunocompromised Patient: A Rare Case Report

Physicians should consider non-O1, non-O139 Vibrio cholerae (NOVC) in the differential diagnosis of cellulitis complicated by sepsis, especially in immunocompromised patients when potential exposure exists. Due to the pathogen's potential for severe infections and rising incidence from environmental changes, we emphasize the need for increased awareness and appropriate treatment guidelines.

Complete genome sequences of sucrose non-fermenting non-O1/non-O139 Vibrio cholerae isolated from human soft tissue infection

This paper describes the hybrid genome assembly of sucrose non-fermenting non-O1/non-O139 Vibrio cholerae isolated from human soft tissue infection. The hybrid assembled genome comprises two circular chromosomes with lengths of 3,001,999 bp and 1,264,051 bp, respectively, with a G + C content of 47.38%.

A novel case of Vibrio bacteremia in an immune-competent patient

Vibrio Cholera, a gram negative bacterium, is notoriously known to cause diarrheal epidemics. The serotypes O1 and O139 are mainly responsible for the diarrheal outbreaks due to the enterotoxin they produce. This enterotoxin however seems to be protective against bacteremia and hence bacteremia is rarely encountered. We report a case of an immune-competent young female who initially presented with hypokalemic periodic paralysis secondary to acute on chronic diarrhea. She was discharged after rehydration and bounced back in septic shock and her blood cultures grew Vibrio Cholera identified on Vitek. She succumbed to this organism within 24 hours of re-admission.

Case report: Characterization and bioinformatics analysis of non-O1/O139 Vibrio cholerae strain isolated from a choledochoduodenal fistula patient with septicemia

The gram-negative bacterium Vibrio cholerae (VC) is divided into multiple serogroups, with groups O1 and O139 responsible for cholera. Conversely, Vibrio cholerae belonging to the non-O1/non-O139 group (NOVC) does not produce cholera-causing toxins. Insufficient understanding of the frequency of NOVC causes fear during the early detection phase. Acute gastroenteritis is often caused by NOVC, while extra gastrointestinal infections are less common. In the case described here, the patient had a postoperative choledochoduodenal fistula due to prior choledochotomy. In August 2023, he was hospitalized with fever and diarrhea. The gram-negative bacilli Vibrio cholerae was isolated from a blood specimen using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The strain was identified as non-O1/O139 by serum agglutination tests. Subsequent whole-genome sequencing and database analysis revealed that the strain possessed resistance genes such as CRP, varG, almG, and QnrVC4, as well as various virulence factors such as RTX, hlyA, VAS, and T3SS. The phylogenetic tree analysis indicated that CQ23-0008VC had close relationship with cholerae strains isolated from aquatic environments. The patient was treated promptly and discharged after being admitted with severe symptoms. However, Bioinformatics analysis indicated that the virulence factors that were identified in the bacteria were significant; thus, these virulence factors can indicate to medical professionals that a patient could have a septicemia caused by NOVC.

Vibrio cholerae-Associated Necrotizing Fasciitis in an Immunocompromised Individual: Trivial Exposure Leading to a Life-Threatening Illness

Vibrio cholerae primarily causes gastrointestinal infections. However, in immunocompromised patients, the presentation can be atypical in the form of extraintestinal manifestation and more invasive disease. We report a patient with human immunodeficiency virus (HIV), who had necrotizing fasciitis in the left leg following exposure to stagnant rainwater. These immunocompromised patients should be educated about the possibility of such life-threatening infection following such a minor exposure.

Non-O1, Non-O139 Vibrio cholerae Bacteremia in an Autoimmune Pancreatitis Patient

Over 200 different serogroups of Vibrio cholerae based on O-polysaccharide specificity have been described worldwide, including the two most important serogroups, O1 and O139. Non-O1/non-O139 V. cholerae serogroups generally do not produce the cholera-causing toxin but do sporadically cause gastroenteritis and extra-intestinal infections. Recently, however, bloodstream infections caused by non-O1/non-O139 V. cholerae are being increasingly reported, and these infections are associated with high mortality in immunocompromised hosts. We describe a case of non-O1/non-O139 V. cholerae bacteremia in a patient with autoimmune pancreatitis and stenosis of the intra- and extrahepatic bile ducts. The clinical manifestations of bacteremia were fever and mild digestive symptoms. The blood cultures showed V. cholerae, which was identified as a non-O1, non-O139 serogroup by slide agglutination tests and PCR. The bloodstream infection of the patient was likely caused by the consumption of contaminated seafood at a banquet. The patient recovered after the administration of a third-generation cephalosporin. Non-O1/non-O139 V. cholerae infection presents with or without gastrointestinal manifestations; close attention should be paid to the possibility of disseminated non-O1/non-O139 V. cholerae infection in high-risk patients.

Vibrio cholerae Bacteremia: An Enigma in Cholera-Endemic African Countries

Cholera is highly endemic in many sub-Saharan African countries. The bacterium Vibrio cholerae is responsible for this severe dehydrating diarrheal disease that accounts for over 100,000 deaths each year globally. In recent years, the pathogen has been found to invade intestinal layers and translocate into the bloodstream of humans. The non-toxigenic strains of V. cholerae (non-O1/O139), also known as NOVC, which do not cause epidemic or pandemic cases of cholera, are the major culprits of V. cholerae bacteremia. In non-cholera-endemic regions, clinical reports on NOVC infection have been noted over the past few decades, particularly in Europe and America. Although low-middle-income countries are most susceptible to cholera infections because of challenges with access to clean water and inappropriate sanitation issues, just a few cases of V. cholerae bloodstream infections have been reported. The lack of evidence-based research and surveillance of V. cholerae bacteremia in Africa may have significant clinical implications. This commentary summarizes the existing knowledge on the host risk factors, pathogenesis, and diagnostics of NOVC bacteremia.

DegS protease regulates antioxidant capacity and adaptability to oxidative stress environment in Vibrio cholerae

Adaptation to oxidative stress is critical for survival of Vibrio cholerae in aquatic ecosystems and hosts. DegS activates the σE envelope stress response. We have previously revealed that DegS may be involved in regulating the oxidative stress response. In this study, we demonstrated that deletion of the degS gene attenuates the antioxidant capacity of V. cholerae. In addition, our results further revealed that the regulation of antioxidant capacity by DegS in V. cholerae could involve the cAMP-CRP complex, which regulates rpoS. XthA is an exonuclease that repairs oxidatively damaged cells and affects the bacterial antioxidant capacity. qRT-PCR showed that DegS, σE, cAMP, CRP, and RpoS positively regulate xthA gene transcription. XthA overexpression partially compensates for antioxidant deficiency in the degS mutant. These results suggest that DegS affects the antioxidant capacity of V.cholerae by regulating xthA expression via the cAMP-CRP-RpoS pathway. In a mouse intestinal colonization experiment, our data showed that V.cholerae degS, rpoE, and rpoS gene deletions were associated with significantly reduced resistance to oxidative stress and the ability to colonize the mouse intestine. In conclusion, these findings provide new insights into the regulation of antioxidant activity by V.cholerae DegS.

Vibrio cholerae-An emerging pathogen in Austrian bathing waters?

Vibrio cholerae, an important human pathogen, is naturally occurring in specific aquatic ecosystems. With very few exceptions, only the cholera-toxigenic strains belonging to the serogroups O1 and O139 are responsible for severe cholera outbreaks with epidemic or pandemic potential. All other nontoxigenic, non-O1/non-O139 V. cholerae (NTVC) strains may cause various other diseases, such as mild to severe infections of the ears, of the gastrointestinal and urinary tracts as well as wound and bloodstream infections. Older, immunocompromised people and patients with specific preconditions have an elevated risk. In recent years, worldwide reports demonstrated that NTVC infections are on the rise, caused amongst others by elevated water temperatures due to global warming.The aim of this review is to summarize the knowledge gained during the past two decades on V. cholerae infections and its occurrence in bathing waters in Austria, with a special focus on the lake Neusiedler See. We investigated whether NTVC infections have increased and which specific environmental conditions favor the occurrence of NTVC. We present an overview of state of the art methods that are currently available for clinical and environmental diagnostics. A preliminary public health risk assessment concerning NTVC infections related to the Neusiedler See was established. In order to raise awareness of healthcare professionals for NTVC infections, typical symptoms, possible treatment options and the antibiotic resistance status of Austrian NTVC isolates are discussed.

Occurrence of Vibrio spp. in Selected Recreational Water Bodies in Belgium during 2021 Bathing Season

In recent years, a global increase in the number of reports of human vibriosis involving V. cholerae non-O1/O139 (NOVC) and other Vibrio spp. has been observed. In this context, the Belgian National Reference Center for Vibrio conducted an assessment of the presence of Vibrio spp. in recreational waters. Water sampling was performed monthly in different lakes in Wallonia and Flanders, including the North Sea. The collected water was then filtrated and cultured, and Vibrio spp. was quantified according to the Most Probable Number (MPN). Presumptive colonies were confirmed via MALDI-TOF, and PCR for virulence genes was applied if justified. No Vibrio spp. was found in the analyzed water bodies in Wallonia. However, NOVC was isolated from three different lakes in Flanders and from coastal water. In addition, V. alginolyticus and V. parahaemolyticus were also detected in coastal water. No clear impact of the pH and temperature was observed on Vibrio spp. occurrence. Our study demonstrates the presence of Vibrio spp. in different bathing water bodies, mostly in the north of Belgium, and supports the recommendation to include Vibrio spp. as a water quality indicator for bathing water quality assessment to ensure the safety of water recreational users in Belgium.

Cellulitis: A Review of Current Practice Guidelines and Differentiation from Pseudocellulitis

Cellulitis, an infection involving the deep dermis and subcutaneous tissue, is the most common reason for skin-related hospitalization and is seen by clinicians across various disciplines in the inpatient, outpatient, and emergency room settings, but it can present as a diagnostic and therapeutic challenge. Cellulitis is a clinical diagnosis based on the history of present illness and physical examination and lacks a gold standard for diagnosis. Clinical presentation with acute onset of redness, warmth, swelling, and tenderness and pain is typical. However, cellulitis can be difficult to diagnose due to a number of infectious and non-infectious clinical mimickers such as venous stasis dermatitis, contact dermatitis, eczema, lymphedema, and erythema migrans. Microbiological diagnosis is often unobtainable due to poor sensitivity of culture specimens. The majority of non-purulent, uncomplicated cases of cellulitis are caused by β-hemolytic streptococci or methicillin-sensitive Staphylococcus aureus, and appropriate targeted coverage of this pathogen with oral antibiotics such as penicillin, amoxicillin, and cephalexin is sufficient. Even with rising rates of community-acquired methicillin-resistant Staphylococcus aureus, coverage for non-purulent cellulitis is generally not recommended.

Population Structure and Multidrug Resistance of Non-O1/Non-O139 Vibrio cholerae in Freshwater Rivers in Zhejiang, China

To understand the environmental reservoirs of Vibrio cholerae and their public health significance, we surveyed freshwater samples from rivers in two cities (Jiaxing [JX] and Jiande [JD]) in Zhejiang, China. A total of 26 sampling locations were selected, and river water was sampled 456 times from 2015 to 2016 yielding 200 V. cholerae isolates, all of which were non-O1/non-O139. The average isolation rate was 47.3% and 39.1% in JX and JD, respectively. Antibiotic resistance profiles of the V. cholerae isolates were examined with nonsusceptibility to cefazolin (68.70%, 79/115) being most common, followed by ampicillin (47.83%, 55/115) and imipenem (27.83%, 32/115). Forty-two isolates (36.52%, 42/115) were defined as multidrug resistant (MDR). The presence of virulence genes was also determined, and the majority of the isolates were positive for toxR (198/200, 99%) and hlyA (196/200, 98%) with few other virulence genes observed. The population structure of the V. cholerae non-O1/non-O139 sampled was examined using multilocus sequence typing (MLST) with 200 isolates assigned to 128 STs and 6 subpopulations. The non-O1/non-O139 V. cholerae population in JX was more varied than in JD. By clonal complexes (CCs), 31 CCs that contained isolates from this study were shared with other parts of China and/or other countries, suggesting widespread presence of some non-O1/non-O139 clones. Drug resistance profiles differed between subpopulations. The findings suggest that non-O1/non-O139 V. cholerae in the freshwater environment is a potential source of human infections. Routine surveillance of non-O1/non-O139 V. cholerae in freshwater rivers will be of importance to public health.

[Atypical bacterial Infections of the Hand]

Atypical infections of the hand are rare and often misdiagnosed. Delay of treatment can lead to irreversible damage, even life-threatening sepsis. The article provides a survey of some of the most frequent atypical infections and their appearance on the hand (Mykobakteria, Vibriones, Francisella, Actinomycetoma), illustrated by two case reports. Knowing the pathogenesis of the most frequent atypical infections allows considering them in the daily practice for differential diagnosis, initiate specific testing, and administer an adequate therapy at an early stage.

Virulence Regulation and Innate Host Response in the Pathogenicity of Vibrio cholerae

The human pathogen Vibrio cholerae is the causative agent of severe diarrheal disease known as cholera. Of the more than 200 "O" serogroups of this pathogen, O1 and O139 cause cholera outbreaks and epidemics. The rest of the serogroups, collectively known as non-O1/non-O139 cause sporadic moderate or mild diarrhea and also systemic infections. Pathogenic V. cholerae circulates between nutrient-rich human gut and nutrient-deprived aquatic environment. As an autochthonous bacterium in the environment and as a human pathogen, V. cholerae maintains its survival and proliferation in these two niches. Growth in the gastrointestinal tract involves expression of several genes that provide bacterial resistance against host factors. An intricate regulatory program involving extracellular signaling inputs is also controlling this function. On the other hand, the ability to store carbon as glycogen facilitates bacterial fitness in the aquatic environment. To initiate the infection, V. cholerae must colonize the small intestine after successfully passing through the acid barrier in the stomach and survive in the presence of bile and antimicrobial peptides in the intestinal lumen and mucus, respectively. In V. cholerae, virulence is a multilocus phenomenon with a large functionally associated network. More than 200 proteins have been identified that are functionally linked to the virulence-associated genes of the pathogen. Several of these genes have a role to play in virulence and/or in functions that have importance in the human host or the environment. A total of 524 genes are differentially expressed in classical and El Tor strains, the two biotypes of V. cholerae serogroup O1. Within the host, many immune and biological factors are able to induce genes that are responsible for survival, colonization, and virulence. The innate host immune response to V. cholerae infection includes activation of several immune protein complexes, receptor-mediated signaling pathways, and other bactericidal proteins. This article presents an overview of regulation of important virulence factors in V. cholerae and host response in the context of pathogenesis.

Intensive care management of a patient with necrotizing fasciitis due to non-O1/O139 Vibrio cholerae after traveling to Taiwan: a case report

Background

Vibrio cholerae are oxidase-positive bacteria that are classified into various serotypes based on the O surface antigen. V. cholerae serotypes are divided into two main groups: the O1 and O139 group and the non-O1/non-O139 group. O1 and O139 V. cholerae are related to cholera infection, whereas non-O1/non-O139 V. cholerae (NOVC) can cause cholera-like diarrhea. A PubMed search revealed that only 16 cases of necrotizing fasciitis caused by NOVC have been recorded in the scientific literature to date. We report the case of a Japanese woman who developed necrotizing fasciitis caused by NOVC after traveling to Taiwan and returning to Japan.

Case presentation

A 63-year-old woman visited our hospital because she had experienced left knee pain for the past 3 days. She had a history of colon cancer (Stage IV: T3N3 M1a) and had received chemotherapy. She had visited Taiwan 5 days previously, where she had received a massage. She was diagnosed with septic shock owing to necrotizing fasciitis. She underwent fasciotomy and received intensive care. She recovered from the septic shock; however, after 3 weeks, she required an above-knee amputation for necrosis and infection. Her condition improved, and she was discharged after 22 weeks in the hospital.

Conclusions

With the increase in tourism, it is important for clinicians to check patients’ travel history. Clinicians should be alert to the possibility of necrotizing fasciitis in patients with risk factors. Necrotizing fasciitis caused by NOVC is severe and requires early fasciotomy and debridement followed by intensive postoperative care.

Non-O1/non-O139 Vibrio cholerae bacteraemia in mainland China from 2005 to 2019: clinical, epidemiological and genetic characteristics

In mainland China, the clinical, epidemiological and genetic features of non-O1/non-O139 Vibrio cholerae (NOVC) bacteraemia have been scarcely investigated. Herein, we describe a patient with NOVC bacteraemia diagnosed in our hospital and present a retrospective analysis of literature reports of 32 other cases in China, detailing the clinical epidemiology, antibiotic resistance and molecular characteristics of isolates. Most patients were male (84.8%; median age, 53 years) and had predisposing factors, such as cirrhosis, malignant tumours, blood diseases and diabetes. In addition to fever, gastroenteritis was the most frequent presenting symptom. The mortality rate during hospitalisation was 12.1%. NOVC bacteraemia cases were more common in June–August, with the majority in coastal provinces and the Yangtze River basin. Only 42.4% of cases were attributed to consumption of marine (aquatic) products. Tetracycline, third-generation cephalosporins, and fluoroquinolones were the most effective antimicrobial agents, and the highest frequencies of resistance were recorded for ampicillin/sulbactam (37.5%), amoxicillin/clavulanic acid (33.3%), ampicillin (29.2%) and sulfamethoxazole (20%). Multi-drug resistant isolates were not detected. Limited data indicate that ctxAB and tcpA genes were absent in all NOVC isolates but other putative virulence genes (hlyA, toxR, hap and rtxA) were common. Ten multilocus sequence types were identified with marked genetic heterogeneity between different isolates. As clinical manifestations of NOVC bacteraemia may vary widely, and isolates exhibit genetic diversity, clinicians and public health experts should be alerted to the possibility of infection with this pathogen because of the high prevalence of liver disease in China.

Two cases of septic shock with different outcomes caused by non-O1/non-O139 Vibrio cholerae isolates

In recent decades, increasing numbers of human infections have been linked to non-O1/non-O139 Vibrio cholerae. Septicemia resulting from non-O1/non-O139 V. cholerae infection is rare but has high mortality. The pathogenesis of non-O1/non-O139 V. cholerae septicemia is poorly understood. Here, we report two sporadic cases of septicemia following non-O1/non-O139 V. cholerae infection from an inland area of China. Patient 1 died rapidly within 24 hours, while patient 2 gradually recovered from septic shock. To explore the reasons for these divergent outcomes, we compared the two cases, tested the antibiotic sensitivity of the two isolates, and investigated their virulence genes and sequence types.

Three cases of fulminant cellulitis caused by non-O1, non-O139 Vibrio cholerae in Southern Finland

Background: Non-O1, non-O139 Vibrio cholerae is endemic in temperate waters. Most often encountered as the pathogen in transient gastroenteritis, it can also cause severe soft tissue infections. While normally a rare pathogen in Finland, we observed seven cases of non-O1, non-O139 V. cholerae infections in Helsinki University Hospital during the hot summer of 2018. Here we present three of these cases with fulminant V. cholerae cellulitis in detail.Methods: Patients with tissue culture positive soft tissue infections between 2017 and 2019 were identified using a local laboratory database. Patients with severe infections requiring surgical revision were included in this series.Results: Three patients with tissue culture positive non-O1, non-O139 V. cholerae cellulitis were identified. All were treated in the summer of 2018 for fulminant lower leg cellulitis. Two patients were febrile and hemodynamically unstable at presentation. One had septicaemia. Surgical revisions were done within the first week of admission, and defects covered with partial-thickness skin grafts several weeks later. Antibiotic treatment varied and continued until the wounds were healed, between one and over two months in total.

Non-O1, Non-O139 Vibrio cholerae (NOVC) Bacteremia: Case Report and Literature Review, 2015-2019

Non-O1, non-O139 Vibrio cholerae (NOVC) does not agglutinate with O1 and O139 antisera and can cause intestinal and extraintestinal infections in immunocompromised individuals. NOVC bacteremia has the highest mortality among NOVC infections, and the number of reports has increased in recent years. Nevertheless, some clinicians are poorly informed about this disease. Herein, we describe a documented case of NOVC bacteremia in a male patient with impaired liver function. Blood cultures revealed the presence of V. cholerae, but this strain showed self-coagulation on the serum agglutination test. To our knowledge, this phenomenon is unreported among cases of NOVC infections. This pathogen was finally confirmed as NOVC via PCR. Because the patient worked as a garbage transporter, he was likely infected after contact with contaminated water through a foot wound. The patient developed septic shock shortly after admission and ultimately died from the illness. This paper reviews 23 cases of NOVC bacteremia from 2015 to 2019. To improve the accuracy of identifying NOVC and analyze its virulence factors, relevant detection methods were reviewed and analyzed.

Non O1 Vibrio cholerae as a cause of bacteremic lower limb cellulitis: A case report

INTRODUCTION

Self-limiting gastroenteritis and wound infections in immunocompetent patients are most of the cases involved with Non-O1, non-O139 Vibrio cholerae which its microorganism occasionally accountable for intestinal and extra-intestinal infections. Cellulitis is an infection of the skin and underlying soft tissue mostly affected by bacteria. Diabetic foot ulcer is the most costly and devastating complication of diabetes mellitus.

CASE PRESENTATION

This following case describes a bacteremic soft tissue infection in a diabetic patient who is 54-year-old male with 6 years of type 2 diabetes mellitus. The patient was treated with surgical debridement of the foot ulcer, calf fasciotomy and medical therapy then he discharged. The next day readmitted with deteriorating of his condition the whole right leg to the level of the knee became ischemic and black with evidence of wet gangrene. A Guillotine above knee amputation was done.

DISCUSSION

Upon review of literature, we only found few cases have been reported of cellulitis due to V. cholerae. A degree of hepatic impairment or immunocompromised state like Diabetes Mellitus, chronic infections, malignancies, and peripheral vascular disease are seen in the majority of non-gastrointestinal V. cholerae infections which suggests that it should be included in the differential diagnosis of bacteremic skin and soft tissue infections in patients with underlying illnesses.

CONCLUSION

Cholerae should be included in the differential diagnosis of any bacteremic skin and soft tissue infections especially in elderly, comorbid and immune-compromised patients. Well-timed, proper antibiotic and surgical treatments are important in management of the infection to decrease morbidity and mortality.

Application of three different methods to determine the prevalence, the abundance and the environmental drivers of culturable Vibrio cholerae in fresh and brackish bathing waters

AIMS

Three cultivation methods were used to study the prevalence and abundance of Vibrio cholerae in Eastern Austrian bathing waters and to elucidate the main factors controlling their distribution.

METHODS AND RESULTS

Vibrio cholerae abundance was monitored at 36 inland bathing sites with membrane filtration (MF), a standard most probable number (MPN) approach and direct plating (DP). Membrane filtration yielded the most reliable and sensitive results and allowed V. cholerae detection at 22 sites with concentrations up to 39 000 CFU per 100 ml, all belonging to serogroups other than O1 and O139 and not coding for cholera toxin and toxin coregulated pilus. Direct plating turned out as an easy method for environments with high V. cholerae abundances, conductivity was the only significant predictor of V. cholerae abundance in the bathing waters at warm water temperatures.

CONCLUSIONS

Vibrio cholerae nonO1/nonO139 are widely prevalent in Eastern Austrian bathing waters. Instead of the standard MPN approach, MF and DP are recommended for V. cholerae monitoring. Conductivity can be used as a first easy-to-measure parameter to identify potential bathing waters at risk.

SIGNIFICANCE AND IMPACT OF THE STUDY

Vibrio cholerae nonO1/nonO139 infections associated with bathing activities are an increasing public health issue in many countries of the northern hemisphere. However, there are only limited data available on the prevalence and abundance of V. cholerae in coastal and inland bathing waters. For monitoring V. cholerae prevalence and abundance, reliable and simple quantification methods are needed. Moreover, prediction of V. cholerae abundance from environmental parameters would be a helpful tool for risk assessment. This study identified the best culture-based quantification methods and a first quick surrogate parameter to attain these aims.

Approach to Aquatic Skin Infections

Aquatic-based infections can present a treatment challenge for primary care physicians because of the likely polymicrobial nature of the infection and the possibility of uncommon pathogenic organisms. Although Staphylococcus and Streptococcus species that colonize the skin are the most common etiologic agents associated with saltwater and freshwater skin and soft tissue infections, other significant pathogens can include Vibrio, Aeromonas, Edwardsiella, Erysipelothrix, and Mycobacterium. Early detection and appropriate management of aquatic infections can significantly decrease morbidity and mortality. This article reviews the pathophysiology, presentation, and management for the most common water-borne pathogens causing skin and soft tissue infections.

Virulence-associated genes and molecular characteristics of non-O1/non-O139 Vibrio cholerae isolated from hepatitis B cirrhosis patients in China

OBJECTIVES

We aimed to report virulence-associated genes and molecular characteristics of non-O1/non-O139 Vibrio cholerae isolated from hepatitis B cirrhosis patients in China.

METHODS

Patient clinical data including course of disease, laboratory tests, antibiotic treatment and outcomes were collected. Antimicrobial susceptibility testing was performed and virulence-associated genes were detected by PCR. Genetic relatedness among non-O1/non-O139 V. cholerae strains was investigated by pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).

RESULTS

All three strains in this study harbored pathogenicity related genes like rtxA, rtxC, toxR, hapA, hlyA and ompW whereas they lacked ctxA, ctxB, tcpA, ompU and zot genes. None of them showed resistance to any antibiotic detected. A new allele of gyrB was submitted to the MLST database and designated as 97. Two novel sequence types (ST518 and ST519) and ST271 were identified by multilocus sequence typing (MLST). PFGE indicated considerable diversity among three non-O1/non-O139 V. cholerae strains.

CONCLUSIONS

Three sporadic cases highlight that non-O1/non-O139 V. cholerae can cause opportunistic invasiveness infection in cirrhosis patients. Pathogenicity may be related to virulence-associated genes. Timely detection and antibiotic therapy should be paid more attention to in clinic.

Spatiotemporal Dynamics of Vibrio cholerae in Turbid Alkaline Lakes as Determined by Quantitative PCR

In recent years, global warming has led to a growing number of Vibrio cholerae infections in bathing water users in regions formerly unaffected by this pathogen. It is therefore of high importance to monitor V. cholerae in aquatic environments and to elucidate the main factors governing its prevalence and abundance. For this purpose, rapid and standardizable methods that can be performed by routine water laboratories are prerequisite. In this study, we applied a recently developed multiplex quantitative PCR (qPCR) strategy (i) to monitor the spatiotemporal variability of V. cholerae abundance in two small soda pools and a large lake that is intensively used for recreation and (ii) to elucidate the main factors driving V. cholerae dynamics in these environments. V. cholerae was detected with qPCR at high concentrations of up to 970,000 genomic units 100 ml-1 during the warm season, up to 2 orders of magnitude higher than values obtained by cultivation. An independent cytometric approach led to results comparable to qPCR data but with significantly more positive samples due to problems with DNA recovery for qPCR. Not a single sample was positive for toxigenic V. cholerae, indicating that only nontoxigenic V. cholerae (NTVC) was present. Temperature was the main predictor of NTVC abundance, but the quality and quantity of dissolved organic matter were also important environmental correlates. Based on this study, we recommend using the developed qPCR strategy for quantification of toxigenic and nontoxigenic V. cholerae in bathing waters with the need for improvements in DNA recovery.IMPORTANCE There is a definitive need for rapid and standardizable methods to quantify waterborne bacterial pathogens. Such methods have to be thoroughly tested for their applicability to environmental samples. In this study, we critically tested a recently developed multiplex qPCR strategy for its applicability to determine the spatiotemporal variability of V. cholerae abundance in lakes with a challenging water matrix. Several qPCR protocols for V. cholerae detection have been developed in the laboratory, but comprehensive studies on the application to environmental samples are extremely scarce. In our study, we demonstrate that our developed qPCR approach is a valuable tool but that there is a need for improvement in DNA recovery for complex water matrices. Furthermore, we found that nontoxigenic V. cholerae is present in very high numbers in the investigated ecosystems, while toxigenic V. cholerae is apparently absent. Such information is of importance for public health.

A comprehensive survey of Aeromonas sp. and Vibrio sp. in seabirds from southeastern Brazil: outcomes for public health

AIMS

To perform a microbiological survey regarding the presence, prevalence and characterization of Aeromonas sp. and Vibrio sp. in debilitated wrecked marine birds recovered from the centre-north coast of the state of Rio de Janeiro, Brazil.

METHODS AND RESULTS

Swabs obtained from 116 alive and debilitated wrecked marine birds, comprising 19 species, from the study area were evaluated by biochemical methods. Antimicrobial susceptibility tests and pathogenicity gene screening were performed for bacterial strains of public health importance. Vibrio sp. and Aeromonas sp. were identified, as well as certain pathogenic genes and resistance to selected antimicrobials.

CONCLUSIONS

This study demonstrates that the identified bacteria, mainly Vibrio sp., are fairly prevalent and widespread among several species of seabirds and highlights the importance of migratory birds in bacterial dispersion. In addition, it demonstrates the importance of the bacterial strains regarding their pathogenic potential. Therefore, seabirds can act as bacterial reservoirs, and their monitoring is of the utmost importance in a public health context.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study comprehensively evaluates the importance of seabirds as bacteria of public health importance reservoirs, since birds comprising several pathogenic bacterial species were evaluated.

Non-O1/non-O139 Vibrio cholerae septicemia in patients with liver cirrhosis and ascites

AIM

To conduct laboratory identification and drug sensitivity testing of suspected Vibrio cholerae isolated from a patient with liver cirrhosis and ascites.

METHODS

By reviewing the patient's clinical symptoms, primary disease, laboratory results, treatment, and prognosis, the bacteria were identified using the Vitek 2 Compact automatic microbial analysis system, manual micro-tube biochemical reaction, and polymerase chain reaction. Drug susceptibility was determined by the K-B paper method, and serum virulence was determined by the slide agglutination method.

RESULTS

After a series of tests, the bacteria were identified as Vibrio cholerae non-O1 non-O139. Drug sensitivity testing showed that the bacteria were sensitive to many antibiotics such as ampicillin, piperacillin, ceftazidime, cefoperazone, shubatan, ceftriaxone, cefepime, imipenem, amikacin, aztreonam,levofloxacin, gatifloxacin, and compound sulfamethoxazole.

CONCLUSION

The bacteria isolated from the patient with liver cirrhosis and ascites were identified as non-O1 non-O139 Vibrio cholerae, which does not produce cholera toxin and is sensitive to common antibiotics.