Serotype Paratyphi Research Articles

Rapid and specific differentiation of Salmonella enterica serotypes typhi and Paratyphi by multicolor melting curve analysis

Rapid and accurate identification of Salmonella enterica serotypes Typhi and Paratyphi (A, B and C), the causal agents of enteric fever, is critical for timely treatment, case management and evaluation of health policies in low and middle-income countries where the disease still remains a serious public health problem. The present study describes the development of a multiplex assay (EFMAtyping) for simultaneous identification of pathogens causing typhoid and paratyphoid fever in a single reaction by the MeltArray approach, which could be finished within 2.5 h. Seven specific genes were chosen for differentiation of typhoidal and nontyphoidal Salmonella. All gene targets were able to be detected by the EFMAtyping assay, with expected Tm values and without cross-reactivity to other relevant Salmonella serovars. The limit of detection (LOD) for all gene targets was 50 copies per reaction. The LOD reached 102–103 CFU/ml for each pathogen in simulated clinical samples. The largest standard deviation value for mean Tm was below 0.5 °C. This newly developed EFMAtyping assay was further evaluated by testing 551 clinical Salmonella isolates, corroborated in parallel by the traditional Salmonella identification workflow, and serotype prediction was enabled by whole-genome sequencing. Compared to the traditional method, our results exhibited 100% of specificity and greater than 96% of sensitivity with a kappa correlation ranging from 0.96 to 1.00. Thus, the EFMAtyping assay provides a rapid, high throughput, and promising tool for public health laboratories to monitor typhoid and paratyphoid fever.

A novel lytic phage infecting MDR Salmonella enterica and its application as effective food biocontrol.

Salmonella enterica is a foodborne pathogen associated with both typhoid and non-typhoid illness in humans and animals. This problem is further exacerbated by the emergence of antibiotic-resistant strains of Salmonella enterica. Therefore, to meet public health and safety, there is a need for an alternative strategy to tackle antibiotic-resistant bacteria. Bacteriophages or (bacterial viruses), due to their specificity, self-dosing, and antibiofilm activity, serve as a better approach to fighting against drug-resistant bacteria. In the current study, a broad-host range lytic phage phiSalP219 was isolated against multidrug-resistant Salmonella enterica serotypes Paratyphi from a pond water sample. Salmonella phage phiSalP219 was able to lyse 28/30 tested strains of Salmonella enterica. Salmonella phage phiSalP219 exhibits activity in acidic environments (pH3) and high temperatures (70°C). Electron microscopy and genome analysis revealed that phage phiSalP219 is a member of class Caudoviricetes. The genome of Salmonella phage phiSalP219 is 146Kb in size with 44.5% GC content. A total of 250 Coding Sequence (CDS) and 25 tRNAs were predicted in its genome. Predicted open reading frames (ORFs) were divided into five groups based on their annotation results: (1) nucleotide metabolism, (2) DNA replication and transcription, (3) structural proteins, (4) lysis protein, and (5) other proteins. The absence of lysogeny-related genes in their genome indicates that Salmonella phage phiSalP219 is lytic in nature. Phage phiSalP219 was also found to be microbiologically safe (due to the absence of toxin or virulence-related genes) in the control of Salmonella enterica serovar Typhimurium infections in the ready-to-eat meat and also able to eradicate biofilm formed by the same bacterium on the borosilicate glass surface.

Comparison of Culture Proven Enteric Fever Treatment with Meropenem Alone Vs Combination of Meropenem and Azithromycin

Background: Enteric fever, primarily caused by Salmonella enterica serotypes Typhi and Paratyphi, remains a significant global health challenge, particularly in regions with limited access to clean water and sanitation. The emergence of multidrug-resistant strains has prompted the exploration of effective antibiotic regimens. While Meropenem has become a critical treatment option, the potential benefit of combining it with Azithromycin is not well established. Objective: The study aimed to compare the efficacy of Meropenem alone versus a combination of Meropenem and Azithromycin in the treatment of culture-proven enteric fever, focusing on fever resolution time and hospital stay duration. Methods: Conducted at the Combined Military Hospital, Peshawar, this study involved 81 patients diagnosed with enteric fever. They were randomly divided into two groups: Group 1 (n=40) received Meropenem alone, and Group 2 (n=41) received a combination of Meropenem and Azithromycin. Key parameters evaluated included gender distribution, age, duration of defervescence, and length of hospital stay. Statistical significance was assessed using appropriate tests. Results: The study found no significant difference in the duration of fever resolution (P=0.571) and hospital stay (P=0.466) between the two groups. The mean defervescence time was 5.325 days for Group 1 and 5.4878 days for Group 2. The average hospital stay was 6.4 days for Group 1 and 6.6098 days for Group 2. Gender distribution and age profile were comparable across both groups. Conclusion: The study concludes that there is no significant difference in the effectiveness of treating enteric fever with Meropenem alone compared to a combination of Meropenem and Azithromycin. This finding supports the use of Meropenem monotherapy as a suitable treatment for enteric fever, potentially reducing treatment protocols and addressing concerns about antibiotic overuse.

2005. Direct Hospitalization Costs Associated with Resistant and Susceptible Salmonella and Shigella Infections in the United States — 2012–2019

Abstract Background Foodborne illnesses cost ∼$90 billion in the United States annually. Antibiotic-resistant infections may be more difficult to treat and can be associated with severe outcomes, leading to higher costs and longer length of stay (LOS). We described LOS and costs for hospital admissions for Salmonella and Shigella infections by resistance status. Methods We reviewed all inpatient admissions from ∼300 hospitals in the Premier Healthcare database during 2012–2019 and included records with culture-confirmed nontyphoidal Salmonella (NTS), typhoidal Salmonella (serotypes Typhi and Paratyphi A, B, and C), or Shigella. We classified infections as resistant if laboratory testing found resistance to ≥1 drug in the clinically important antibiotic categories (fluoroquinolones, macrolides, penicillins, folate pathway antagonists, or third-generation cephalosporins) or susceptible otherwise. We used the Wilcoxon rank sum test to assess difference in median LOS and cost of patient hospitalization for resistant vs. susceptible infections by pathogen type. Results Of 4,168 persons hospitalized, about half (n=2,129, 51%) were female; median age was 52 [IQR: 26‒68] years; 29% (n=1,217) of infections were resistant. For NTS infections, median LOS was 4 [IQR: 3‒7] days for resistant and 4 [IQR: 3‒6] (p=0.04) for susceptible; for typhoidal Salmonella, 6 [IQR: 5‒8] for resistant and 5 [IQR: 3‒8] for susceptible (p=0.15); and for Shigella, 3 [IQR: 2‒4] for both (p=0.09). Median costs were highest for typhoidal Salmonella ($12,577 resistant vs. $9,238 susceptible; p=0.21), followed by NTS ($7,179 vs $6,421, p=0.01) and Shigella ($4,975 vs $5,335; p=0.26). Conclusion Hospitalization costs were higher for patients with some resistant infections. Longer LOS may contribute to higher costs; however, it is not clear whether other pathogen or patient factors (e.g., comorbidities) also contributed. Additional data and adjusted analyses may provide insight into reasons for the cost difference. If resistant infections are shown to be the cause, our findings support that public health interventions to limit the spread of resistant infections could reduce costs. Disclosures All Authors: No reported disclosures.

Acute febrile illness among outpatients seeking health care in Bangladeshi hospitals prior to the COVID-19 pandemic.

Understanding the distribution of pathogens causing acute febrile illness (AFI) is important for clinical management of patients in resource-poor settings. We evaluated the proportion of AFI caused by specific pathogens among outpatients in Bangladesh. During May 2019-March 2020, physicians screened patients aged ≥2 years in outpatient departments of four tertiary level public hospitals. We randomly enrolled patients having measured fever (≥100.4°F) during assessment with onset within the past 14 days. Blood and urine samples were tested at icddr,b through rapid diagnostic tests, bacterial culture, and polymerase chain reaction (PCR). Acute and convalescent samples were sent to the Centers for Disease Control and Prevention (USA) for Rickettsia and Orientia (R/O) and Leptospira tests. Among 690 patients, 69 (10%) had enteric fever (Salmonella enterica serotype Typhi orSalmonella enterica serotype Paratyphi), 51 (7.4%) Escherichia coli, and 28 (4.1%) dengue detected. Of the 441 patients tested for R/O, 39 (8.8%) had rickettsioses. We found 7 (2%) Leptospira cases among the 403 AFI patients tested. Nine patients (1%) were hospitalized, and none died. The highest proportion of enteric fever (15%, 36/231) and rickettsioses (14%, 25/182) was in Rajshahi. Dhaka had the most dengue cases (68%, 19/28). R/O affected older children and young adults (IQR 8-23 years) and was detected more frequently in the 21-25 years age-group (17%, 12/70). R/O was more likely to be found in patients in Rajshahi region than in Sylhet (aOR 2.49, 95% CI 0.85-7.32) between July and December (aOR 2.01, 1.01-5.23), and who had a history of recent animal entry inside their house than not (aOR 2.0, 0.93-4.3). Gram-negative Enterobacteriaceae were the most common bacterial infections, and dengue was the most common viral infection among AFI patients in Bangladeshi hospitals, though there was geographic variability. These results can help guide empiric outpatient AFI management.

Incidence of typhoid and paratyphoid fever in Bangladesh, Nepal, and Pakistan: results of the Surveillance for Enteric Fever in Asia Project

SummaryBackgroundPrecise enteric fever disease burden data are needed to inform prevention and control measures, including the use of newly available typhoid vaccines. We established the Surveillance for Enteric Fever in Asia Project (SEAP) to inform these strategies.MethodsFrom September, 2016, to September, 2019, we conducted prospective clinical surveillance for Salmonella enterica serotype Typhi (S Typhi) and Paratyphi (S Paratyphi) A, B, and C at health facilities in predetermined catchment areas in Dhaka, Bangladesh; Kathmandu and Kavrepalanchok, Nepal; and Karachi, Pakistan. Patients eligible for inclusion were outpatients with 3 or more consecutive days of fever in the last 7 days; inpatients with suspected or confirmed enteric fever; patients with blood culture-confirmed enteric fever from the hospital laboratories not captured by inpatient or outpatient enrolment and cases from the laboratory network; and patients with non-traumatic ileal perforation under surgical care. We used a hybrid surveillance model, pairing facility-based blood culture surveillance with community surveys of health-care use. Blood cultures were performed for enrolled patients. We calculated overall and age-specific typhoid and paratyphoid incidence estimates for each study site. Adjusted estimates accounted for the sensitivity of blood culture, the proportion of eligible individuals who consented and provided blood, the probability of care-seeking at a study facility, and the influence of wealth and education on care-seeking. We additionally calculated incidence of hospitalisation due to typhoid and paratyphoid.FindingsA total of 34 747 patients were enrolled across 23 facilitates (six tertiary hospitals, surgical wards of two additional hospitals, and 15 laboratory network sites) during the study period. Of the 34 303 blood cultures performed on enrolled patients, 8705 (26%) were positive for typhoidal Salmonella. Adjusted incidence rates of enteric fever considered patients in the six tertiary hospitals. Adjusted incidence of S Typhi, expressed per 100 000 person-years, was 913 (95% CI 765–1095) in Dhaka. In Nepal, the adjusted typhoid incidence rates were 330 (230–480) in Kathmandu and 268 (202–362) in Kavrepalanchok. In Pakistan, the adjusted incidence rates per hospital site were 176 (144–216) and 103 (85–126). The adjusted incidence rates of paratyphoid (of which all included cases were due to S Paratyphi A) were 128 (107–154) in Bangladesh, 46 (34–62) and 81 (56–118) in the Nepal sites, and 23 (19–29) and 1 (1–1) in the Pakistan sites. Adjusted incidence of hospitalisation was high across sites, and overall, 2804 (32%) of 8705 patients with blood culture-confirmed enteric fever were hospitalised.InterpretationAcross diverse communities in three south Asian countries, adjusted incidence exceeded the threshold for “high burden” of enteric fever (100 per 100 000 person-years). Incidence was highest among children, although age patterns differed across sites. The substantial disease burden identified highlights the need for control measures, including improvements to water and sanitation infrastructure and the implementation of typhoid vaccines.FundingBill & Melinda Gates Foundation.

A duplex real-time NASBA assay targeting a serotype-specific gene for rapid detection of viable Salmonella Paratyphi C in retail foods of animal origin.

Salmonella enterica serovar Paratyphi C is highly adapted to humans and can cause a typhoid-like disease with high mortality rates. In this study, three serovar-specific genes were identified by comparative genomics for Salmonella Paratyphi C, SPC_0871, SPC_0872, and SPC_0908. Based on the SPC_0908 and xcd genes for testing Salmonella spp., we developed a duplex real-time nucleic acid sequence-based amplification (real-time NASBA) with a molecular beacon approach for the simultaneous detection of viable cells of Salmonella spp. and serotype Paratyphi C. The test selectively and consistently detected 53 Salmonella spp. (representing 31 serotypes) and 18 non-Salmonella strains. Additionally, the method showed high resistance to interference from natural background flora in pork and chicken samples. The sensitivity of the established approach was determined to be 4.89 cfu/25 g in artificially contaminated pork and chicken samples after pre-enrichment. We propose this NASBA-based protocol as a potential detection method for Salmonella spp. and serotype Paratyphi C in foods of animal origin.

Burden of enteric fever at three urban sites in Africa and Asia: a multicentre population-based study

SummaryBackgroundEnteric fever is a serious public health concern in many low-income and middle-income countries. Numerous data gaps exist concerning the epidemiology of Salmonella enterica serotype Typhi (S Typhi) and Salmonella enterica serotype Paratyphi (S Paratyphi), which are the causative agents of enteric fever. We aimed to determine the burden of enteric fever in three urban sites in Africa and Asia.MethodsIn this multicentre population-based study, we did a demographic census at three urban sites in Africa (Blantyre, Malawi) and Asia (Kathmandu, Nepal and Dhaka, Bangladesh) between June 1, 2016, and Sept 25, 2018. Households were selected randomly from the demographic census. Participants from within the geographical census area presenting to study health-care facilities were approached for recruitment if they had a history of fever for 72 h or more (later changed to >48 h) or temperature of 38·0°C or higher. Facility-based passive surveillance was done between Nov 11, 2016, and Dec 31, 2018, with blood-culture collection for febrile illness. We also did a community-based serological survey to obtain data on Vi-antibody defined infections. We calculated crude incidence for blood-culture-confirmed S Typhi and S Paratyphi infection, and calculated adjusted incidence and seroincidence of S Typhi blood-culture-confirmed infection.Findings423 618 individuals were included in the demographic census, contributing 626 219 person-years of observation for febrile illness surveillance. 624 S Typhi and 108 S Paratyphi A isolates were collected from the blood of 12 082 febrile patients. Multidrug resistance was observed in 44% S Typhi isolates and fluoroquinolone resistance in 61% of S Typhi isolates. In Blantyre, the overall crude incidence of blood-culture confirmed S Typhi was 58 cases per 100 000 person-years of observation (95% CI 48–70); the adjusted incidence was 444 cases per 100 000 person-years of observation (95% credible interval [CrI] 347–717). The corresponding rates were 74 (95% CI 62–87) and 1062 (95% CrI 683–1839) in Kathmandu, and 161 (95% CI 145–179) and 1135 (95% CrI 898–1480) in Dhaka. S Paratyphi was not found in Blantyre; overall crude incidence of blood-culture-confirmed S Paratyphi A infection was 6 cases per 100 000 person-years of observation (95% CI 3–11) in Kathmandu and 42 (95% CI 34–52) in Dhaka. Seroconversion rates for S Typhi infection per 100 000 person-years estimated from anti-Vi seroconversion episodes in serological surveillance were 2505 episodes (95% CI 1605–3727) in Blantyre, 7631 (95% CI 5913–9691) in Kathmandu, and 3256 (95% CI 2432–4270) in Dhaka.InterpretationHigh disease incidence and rates of antimicrobial resistance were observed across three different transmission settings and thus necessitate multiple intervention strategies to achieve global control of these pathogens.FundingWellcome Trust and the Bill & Melinda Gates Foundation.

Detecting Phenotypic and Genotypic of the Antibiotic Resistant Salmonella enterica Serotype Paratyphi Isolated from Blood Samples in Najaf Province /Iraq

Background & Objectives: Salmonella Paratyphi is a leading cause of human paratyphoid fever in developing countries, causing deaths in humans worldwide. There are several paths for catching paratyphoid fever, but the close contact between patients and healthy humans is so far the most frequent cause of human infections. No study is found about the antibiotic resistance (phenotypic and genetic) of S. Paratyphi isolated from patients in Al-Najaf Province/Iraq, to the researcher’s best knowledge. Hence, this study aimed to determine the prevalence of S. Paratyphi isolates from blood specimens and the antibiotic resistance determinants of them, as well as the genetic relationship among isolates. Methods and Results: Blood specimens from 1743 patients with suspected enteric fever were cultured for the identification of Salmonella enterica during the period from first April to the end of October 2017. 107 (6.14%) S. enterica isolates were recovered and only two (1.87%) of isolates were S. enterica serovar Paratyphi B. These two isolates (ST39 and ST89) were tested against 23 antibiotics using the disc diffusion method on Muller-Hinton agar and the genotypic antibiotic resistance determinants by PCR. ST39 isolate was sensitive to all antibiotics while ST89 isolate was resistant to only cefepime, piperacillin and tobramycin. ST39 isolate did not carry integrons (1 or 2) and any resistance determinants, while ST89 isolate carried integron class1 as well as blaTEM, blaCTX-M and aac(6')-lb genes. Conclusions: The findings of S. Paratyphi isolates with integron 1 and resistant antibiotic genes indicating public health risks.

Association of quorum sensing and biofilm formation with Salmonella virulence: story beyond gathering and cross-talk

Enteric fever (typhoid and paratyphoid fever) is a public health concern which contributes to mortality and morbidity all around the globe. It is caused mainly due to ingestion of contaminated food and water with a gram negative, rod-shaped, flagellated bacterium known as Salmonella enterica serotype typhi (typhoid fever) or paratyphi (paratyphoid fever). Clinical problems associated with Salmonellosis are mainly bacteraemia, gastroenteritis and enteric fever. The bacteria undergo various mechanisms to escape itself from immune reaction of the host, modulating immune response at the site of infection leading to virulence factor production and anti-microbial resistance. Biofilm is one of the adaptation mechanisms through which Salmonella survives in unfavourable conditions and thus is considered as a major threat to public health. Another property of the bacteria is "Quorum Sensing", which is a cell-cell communication and most of the pathogenic bacteria use it to coordinate the production of several virulence factors and other behaviours such as swarming and biofilm formation. Earlier, quorum sensing was believed to be just a medium for communication but, later on, its role in virulence has been studied. However, there are negligible information relating to interaction between quorum sensing and biofilm formation and how these events play crucial role in Salmonella pathogenesis. The review is a summary of updated information regarding how Salmonella uses these properties to spread more and survive better, making a challenge for clinicians and public health experts. Therefore, this review would help bring an insight regarding how biofilm formation and quorum sensing are inter-related and their role in pathogenesis and virulence of Salmonella.

Genome-wide analysis provides a deeper understanding of the population structure of the Salmonella enterica serotype Paratyphi B complex in Bangladesh.

The Salmonella enterica serotype Paratyphi B complex causes a wide range of diseases, from gastroenteritis to paratyphoid fever, depending on the biotypes Java and sensu stricto. The burden of Paratyphi B biotypes in Bangladesh is still unknown, as these are indistinguishable by Salmonella serotyping. Here, we conducted the first whole-genome sequencing (WGS) study on 79 Salmonella isolates serotyped as Paratyphi B that were collected from 10 nationwide enteric disease surveillance sites in Bangladesh. Placing these in a global genetic context revealed that these are biotype Java, and the addition of these genomes expanded the previously described PG4 clade containing Bangladeshi and UK isolates. Importantly, antimicrobial resistance (AMR) genes were scarce amongst Bangladeshi S. Java isolates, somewhat surprisingly given the widespread availability of antibiotics without prescription. This genomic information provides important insights into the significance of S. Paratyphi B biotypes in enteric disease and their implications for public health.

Investigation of Typhoid Fever and their Associated Risk Factors in Children Attending “Deo Gratias” Hospital in Douala, Littoral, Cameroon

Typhoid fever is a communicable disease transmitted by the bacteria Salmonella typhi, related to serotype paratyphi A, B and C. The disease is a significant health concern in most developing countries especially Cameroon. Objectives: The study aimed at assessing the risk factors associated to typhoid fever in children (0-18 years) attending the “Deo Gratias” hospital in Douala. Method: A hospital based cross sectional study from August to September 2018 was carried out in children aged 0-18 years suffering from typhoid fever at the Deo gratias Catholic hospital. Widal slide agglutination and stool culture were the diagnostic test used. Positive confirmed cases were administered questionnaires to evaluate the level of knowledge, attitude and practice toward the disease. Data obtained from respondents was analyzed by descriptive statistics. One-way ANOVA and means comparison using Tukey’s test (α = 0.05) was performed to check whether the population of respondents differed significantly across risk factor practices. Results were finally presented on bar charts, tables and pie chart. Results: Out of 64 patients tested for typhoid, 44 (68.75 %) were confirmed positive. Typhoid fever was more prevalent in females (52.3 %) than in males (47.7 %), with a high proportion in the ages 5-9 years (38.6 %). A significant difference was observed in population of respondents across risk factor practices. Conclusion: Water quality have a great impact on the burden of typhoid fever among children. The identification of risk factors associated to the disease is of great importance in the development of rational control strategies of the disease.

A Study of Paratyphoid Fever in Bulgarian Children

Abstract Objective. To study both the molecular discrimination of D-tartrate fermenting and non-fermenting strains of Salmonella enterica subsp. enterica serotype Paratyphi B isolated from patients with paratyphoid fever and the clinical course of this disease. Materials and methods. The isolates examined were from children aged 3 months to 9 years. A total of 33 Salmonella strains were serotyped as Salmonella Paratyphi B, with an antigenic formula based on O- and H- antigens: 1,4, [5], 12: b: 1,2 by Kauffmann–White classification. Results. Multiplex PCR analysis confirmed all tested strains as d-tartrate fermenting (dT+), also referred to as variant Java. Discussion. We found that the most common cause of paratyphoid fever among children in Bulgaria is variant Java Salmonella Paratyphi B. Most children had classic symptoms of acute gastroenteritis – fever, watery diarrhea and vomiting.

Determination Of Sonographic Common Abdominal Findings Among Patients Suffering From Typhoid Fever

Typhoid fever is a potentially multi systemic and fatal illness, and this serious systemic infection caused by salmonella enterica serotype typhi and paratyphi which are both gram-negative bacteria
 Objectives: To determine the sonographic common abdominal findings among patients suffering from typhoid fever.
 Methods: This research was conducted at Al Qaim Ultrasound Centre and Islamia Hospital Chiniot in nine months duration. Honda Electronics (HS 2000, HS 2200, and Toshiba just vision) machines were used. Frequency range of 3.5-5.00 MHz was used. All the patients were enrolled voluntarily after explaining the procedure to the patient thoroughly. Statistical Package of Social Sciences (SPSS) version 21 was used to evaluate the data
 Results: In this study 176 patients were included, which clinically diagnosed suffering from typhoid fever and laboratory findings also showing positive results. All male and female patients of all age groups, who were clinically suspected of having typhoid fever, either acute or chronic. All male and female healthy individuals and noncooperative patients. Out of 176 patients, 91 were female and 85 males. Laboratory findings, 47(26.7%),56(31.8%),21(11.9%),52(29.5%) patients having (TyphidotIgG), (TyphidotIgM), (TyphidotIgG, IgM), (Widal) positive results respectively. Common abdominal findings on ultrasonography were 62(35.2%) patients with having hepatomegaly, and 88(50%) patients with splenomegaly. Mesenteric lymph adenitis showed only in 21(11.9%) patients. Results showed 27(15.3%) patients with bowel wall thickening, and 13(7.4%) patients with having acalculous-cholecystitis.
 Conclusions: Ultrasonography is a useful and helpful tool in diagnosing the typhoid fever, especially when serological tests are time consuming or showing negative results or cultures. Ultrasonography is also a quick, economical and non-invasive procedure.

Prevalence of Enteric Fever Pathogens Isolated from Blood Culture at a Tertiary Care Centre.

Typhoid fever and paratyphoid fever commonly called as enteric fever is a life-threatening illness caused by Salmonella serotype Typhi and Salmonella serotype Paratyphi, respectively. It is a major public health issue in underdeveloped and developing countries. The aim of the study is to find out the prevalence of enteric fever pathogens in blood culture of patients attending a tertiary care centre. A descriptive cross-sectional study was conducted in 3483 blood samples of patients attending a tertiary care centre, with the history and symptoms suspicious of enteric fever during one year period from mid-September 2019 to mid-September 2020 after ethical approval from the institutional review committee. Isolates were identified by standard microbiological methods and tested for in vitro antibiotic susceptibility by modified kirby-bauer disc diffusion method. The obtained data was entered and analyzed in WHONET 5.6 program, point estimate at 95% was calculated along with frequency and proportion for binary data. In our study, enteric fever pathogens were isolated from 18 (0.51%) blood samples. Out of which, Salmonella Paratyphi A was isolated from 10 (8.19%) and Salmonella Typhi was isolated from 8 (6.55%) blood samples. Other serotypes were not isolated. Antimicrobial susceptibility test showed that salmonella species that was isolated were sensitive to most of the drugs. Prevalence of enteric fever pathogens was lesser compared to other studies. Varying degrees of antibiotic resistance among isolated enteric fever pathogens necessitates continuous surveillance of the susceptibility patterns. Prudent use of antimicrobials, active infection control practices and stringent antibiotic policy should be implemented to prevent emergence of antibiotic resistance and future outbreaks.

Genotypic Characterization of Antimicrobial Resistant Salmonella spp. Strains from Three Poultry Processing Plants in Colombia.

The poultry industry in Colombia has implemented several changes and measures in chicken processing to improve sanitary operations and control pathogens’ prevalence. However, there is no official in-plant microbial profile reference data currently available throughout the processing value chains. Hence, this research aimed to study the microbial profiles and the antimicrobial resistance of Salmonella isolates in three plants. In total, 300 samples were collected in seven processing sites. Prevalence of Salmonella spp. and levels of Enterobacteriaceae were assessed. Additionally, whole-genome sequencing was conducted to characterize the isolated strains genotypically. Overall, the prevalence of Salmonella spp. in each establishment was 77%, 58% and 80% for plant A, B, and C. The mean levels of Enterobacteriaceae in the chicken rinsates were 5.03, 5.74, and 6.41 log CFU/mL for plant A, B, and C. Significant reductions were identified in the counts of post-chilling rinsate samples; however, increased levels were found in chicken parts. There were six distinct Salmonella spp. clusters with the predominant sequence types ST32 and ST28. The serotypes Infantis (54%) and Paratyphi B (25%) were the most commonly identified within the processing plants with a high abundance of antimicrobial resistance genes.

Estimation of Baseline Widal Antibody Titers among Apparently Healthy Urban Population of District Jammu.

Introduction:Definitive diagnosis of Enteric fever is by blood culture for Salmonella enterica serotype Typhi, Paratyphi A, and Paratyphi B which takes long turnaround time and is costly, whereas Widal test is simple, rapid, and cost-effective test whose interpretation depends on the baseline Widal titers among healthy individuals in a defined population.Objectives:To determine the baseline Widal titers among apparently healthy urban population of district Jammu (J&K).Materials and Methods:302 individuals in the age group of 18–50 years were recruited. A pretested questionnaire was used to collect demographic and clinical details. The Widal testing was done using commercial Salmonella antigen kit.Results:A total of 302 samples were screened by Widal test. 138 samples (45.69%) were reactive for TO antigen and 64 (21.19%) tested reactive for TH antigen, 3 (0.01%) samples showed agglutination for AH antigen and 3 (0.01%) were positive for BH antigen. Majority of seropositive samples were in dilutions of 1:40 for both TO and TH antigens.Conclusions:Hence, next higher dilutions showing positivity for both TO and TH antigens, i.e., ≥1:80 may be considered diagnostic for enteric fever in the urban population of Jammu district.

Enteric fever with rhabdomyolysis, multisystem failure and polyneuropathy in a young male – A case report

Background: Enteric fever or Typhoid is a common systemic infection seen in South East Asia and is caused by Salmonella enterica serotypes Typhi, Paratyphi A, Paratyphi B, Paratyphi C and Cholerasuis. Even though Enteric fever usually presents with fever and gastrointestinal symptoms, of late there is an increasing trend of multisystem complications in this region. The incidence of infection with the less virulent S. Paratyphi A seems to be increasing in India. Case Description: A 31 y old Indian male presented to our hospital with 5 d history of fever, headache, severe generalised myalgia, icterus, vomiting, swelling of both lower limbs and passage of cola coloured urine. On admission, he was bed bound due to severe myalgia but was hemodynamically stable. His systemic examination was insignificant except for a mild epigastric tenderness and a palpable nontender hepatomegaly. Investigations showed leucocytosis, mild thrombocytopenia, deranged LFT and renal failure. His serum lipase was found to be elevated at 2115 U/L and abdominal ultrasound was suggestive of pancreatitis. Viral serology for HIV, HBsAg, AntiHCV, AntiHAV, Dengue IgM and Leptospira IgM ECLIA were all negative. His blood culture grew Salmonella Paratyphi A on the third day of hospital stay. CPK levels were grossly elevated at 791,000 IU/L. He was diagnosed as Paratyphoid sepsis with severe rhabdomyolysis, acute renal failure, acute hepatitis and acute pancreatitis. He was treated with a combination of Piperacillin-Tazobactam and Azithromycin along with hemodialysis for his oliguric renal failure. He later developed weakness and paraesthesia of bilateral lower legs with generalized areflexia. His NCS showed acute bilateral upper and lower limb demyelinating polyradiculoneuropathy, which was treated conservatively. He developed malena the next day, colonoscopy showed ileocaecal bleeding and was controlled with local adrenaline injections. He improved significantly with treatment and was discharged from the hospital with complete resolution of all the complications of his Paratyphoid septicaemia. Discussion: Paratyphoid infection presenting with rhabdomyolysis, renal failure, liver failure, pancreatitis, gastrointestinal bleed and AIDP in one patient which resolved with treatment is not reported before. Conclusion: This case suggests that a vigilant approach to look for multi-system complications in Enteric fever and its timely management is justifiable.

Diagnostic Value of Clinical Features to Distinguish Enteric Fever From Other Febrile Illnesses in Bangladesh, Nepal, and Pakistan.

BackgroundEnteric fever, a bacterial infection caused by Salmonella enterica serotypes Typhi and Paratyphi A, frequently presents as a nonlocalizing febrile illness that is difficult to distinguish from other infectious causes of fever. Blood culture is not widely available in endemic settings and, even when available, results can take up to 5 days. We evaluated the diagnostic performance of clinical features, including both reported symptoms and clinical signs, of enteric fever among patients participating in the Surveillance for Enteric Fever in Asia Project (SEAP), a 3-year surveillance study in Bangladesh, Nepal, and Pakistan.MethodsOutpatients presenting with ≥3 consecutive days of reported fever and inpatients with clinically suspected enteric fever from all 6 SEAP study hospitals were eligible to participate. We evaluated the diagnostic performance of select clinical features against blood culture results among outpatients using mixed-effect regression models with a random effect for study site hospital. We also compared the clinical features of S. Typhi to S. Paratyphi A among both outpatients and inpatients.ResultsWe enrolled 20 899 outpatients, of whom 2116 (10.1%) had positive blood cultures for S. Typhi and 297 (1.4%) had positive cultures for S. Paratyphi A. The sensitivity of absence of cough was the highest among all evaluated features, at 65.5% (95% confidence interval [CI], 55.0–74.7), followed by measured fever at presentation at 59.0% (95% CI, 51.6–65.9) and being unable to complete normal activities for 3 or more days at 51.0% (95% CI, 23.8–77.6). A combined case definition of 3 or more consecutive days of reported fever and 1 or more of the following (a) either the absence of cough, (b) fever at presentation, or (c) 3 or more consecutive days of being unable to conduct usual activity--yielded a sensitivity of 94.6% (95% CI, 93.4–95.5) and specificity of 13.6% (95% CI, 9.8–17.5).ConclusionsClinical features do not accurately distinguish blood culture–confirmed enteric fever from other febrile syndromes. Rapid, affordable, and accurate diagnostics are urgently needed, particularly in settings with limited or no blood culture capacity.

Differentiating Entamoeba hystolytica, E. disparandE. moshkovskii in stool sample from rural community of Nepal using nested-PCR

Background: Salmonella enteric serovar Typhi is a gram-negative, rod-shaped facultative anaerobe that only infects humans which is major causative agent for typhoid fever. Enteric fever is a systemic infection of reticuloendothelial system caused by the human adapted pathogens Salmonella enterica serotype Typhi and Salmonella enterica serotype paratyphi A, B. However, the prevalence of Salmonella enterica B and C infection has not been reported in Nepal so for. Methods and materials: A total of 270 faecal samples were collected from south eastern terai region of Nepal after the informed consent form. The samples were processed for microscopic examination of Entamoeba species along with other intestinal parasites. Additionally, Nested- PCR was carried out for characterisation of microscopically positive fecal samples containing the E complex. Results: Of the 270 stool sample from diarrheal patients, 67.3% were male whereas only 32.7% were female. Microscopy-positive fecal samples containing the E complex (n = 56) were subject to PCR for confirmation of the diagnosis of E complex whereas PCR products were detected in 46 samples. Surprisingly, out of 46 PCR-positive samples, only 3 samples were reported to contain E. histolytica. Likewise, among total sample, viral diarrheal was most significant form of diarrhoea found in 76.67% of patients. Among different organisms, As. Lumbricoids and E. histolytica, G. lambia and H. nana were identified in most of the patients accounting for 11.11%, 8.52%, 2.59% and 1.11% respectively. However, Lumbricoids, G. lambia, Teniasoliumand E. histolytica were present in an individual patient while two patient was found with both As. Lumbricoids and G. lambia.Among several symptoms, diarrhoea seems to be the common symptoms infecting all of the patients which is followed by fever and vomiting which accounts for 55.1% and 46.2% correspondingly. Whereas, nausea appears to be the least common symptoms infecting only 14.4% of patients. Conclusion: Molecular techniques are indeed promising tools for epidemiological studies, particularly in discriminating the pathogenic from the non-pathogenic species, which is beneficial for proper diagnosis, immunological assay and drug testing. This is the first study in Nepal using molecular techniques to determine the true incidence of E complex and highlights the molecular methods to differentiate among the species.