Resistencia a nitrofuranos en Salmonella enterica aisladas de carne para consumo humano / Nitrofuran resistance in Salmonella enterica isolated from meat for human consumption

RESUMEN En el presente estudio, se analizaron los mecanismos de resistencia a nitrofuranos en 18 muestras cár nicas con Salmonella enterica (15 de pollo, 2 de ternera y 1 de cerdo) de mercados de Lima (Perú). Determinaron los serotipos de los aislamientos y la sensibilidad a furazolidona y nitrofurantoina (con y sin el inhibidor de bombas de expulsión Phenyl-Arginine-β-Naphthylamide [PAβN]), las mutaciones en los genes snrA y cnr por PCR y la transferabilidad de la resistencia por conjugación. Se identificaron 15 muestras con S. infantis (13 muestras de pollo), 2 con S. enteritidis y 1 con S. anatum. Todos los aisla mientos, excepto S. anatum, fueron resistentes a ambos nitrofuranos (concentración mínima inhibidora [CMI] a furazolidona: 32-64 µg/mL, CMI a nitrofurantoina: 128-256 µg/mL), sin diferencias al adicio narse PAβN. Todos los aislamientos resistentes a nitrofuranos presentaron sustituciones en snrA y cnr (S. infantis: snrA STOP-151; cnr STOP-137; S. enteritidis: snrA STOP-180; cnr STOP-179). No se detectaron mecanismos transferibles de resistencia a nitrofuranos.

ABSTRACT The mechanisms of resistance to nitrofurans from 18 meat samples with Salmonella enterica (chicken: 15; beef: 2; pork: 1) collected in Lima (Peru) were analyzed. The isolates were serotyped and the susceptibility levels to furazolidone and nitrofurantoin [with and without the efflux pump inhibitor Phenyl-Arginine- β-naphthylamide (PAβN)], the presence of mutations in the snrA and cnr genes and the transferability of resistance by conjugation were established. Fifteen samples with S. infantis (13 from chicken samples), 2 with S. enteritidis and 1 with S. anatum were identified. All isolates except the S. anatum were resistant to both nitrofurans showing MICs (minimum inhibitory concentration) of furazolidone and nitrofurantoin of 32-64 μg/mL and 128-256 μg/mL, respectively. The addition of PAßN had no effect on the MIC levels. All nitrofuran-resistant isolates showed amino acid codon alterations at both snrA and cnr (S. infantis: snrA STOP-151; cnr STOP-137; S. enteritidis: snrA STOP-180; cnr STOP-179). No transferable mecha nisms of nitrofuran resistance were detected.

A common Salmonella Enteritidis sequence type from poultry and human gastroenteritis in Ibagué, Colombia / Un tipo de secuencia común de Salmonella Enteritidis de origen aviar y de humano con gastroenteritis en Ibagué, Colombia

Abstract Introduction: Salmonella Enteritidis is a major cause of human salmonellosis in the world, with contaminated eggs and raw chicken meat as the main routes of infection. The main Salmonella spp. serovars circulating in laying hen farms, the surface of eggs, and in raw chicken carcasses have been identified in Ibagué, Colombia. However, it is unknown whether those serovars are responsible for human gastroenteritis. Objective: To evaluate the genetic relationship between gastroenteritis and Salmonella Enteritidis isolates from poultry and humans using multilocus sequence typing (MLST). Materials and methods: Salmonella spp. was isolated from clinical cases of gastroenteritis (n=110). Antibiotic susceptibility tests, followed by serotyping and MLST were conducted and S. Enteritidis was compared to those from laying hen farms and marketed eggs. Results: Ten isolates of Salmonella spp. were obtained from the stools of people with gastroenteritis. The prevalence of Salmonella spp. in human stools was 9.09%, and S. Enteritidis (n=4), S. Typhymurium (n=2), S. Newport (n=1), S. Uganda (n=1), S. Grupensis (n=1), and S. Braenderup (n=1) were the main serotypes. MLST indicated that a common S. Enteritidis sequence type (ST11) was present in all three sources and showed the same antibiotic resistance pattern. Conclusion: Salmonella Enteritidis ST11 constitutes a link between consumption and manipulation of contaminated eggs and human gastroenteritis in Ibagué. Additional studies would be required to establish if other Salmonella serovars isolated from raw chicken meat are also associated with human gastroenteritis.

Resumen Introducción. Salmonella Enteritidis es una de las mayores causas de salmonelosis en el mundo; los huevos contaminados y la carne de pollo cruda son sus principales fuentes de infección. En Ibagué, Colombia, se han identificado los principales serovares que circulan en granjas, superficies de huevos y canales de pollo, pero se desconoce si esos serovares son responsables de la gastroenteritis. Objetivo. Evaluar la relación genética entre los aislamientos de Salmonella Enteritidis de aves de corral y de humanos con la gastroenteritis mediante tipificación de multiloci de secuencias (Multilocus Sequence Typing, MLST). Materiales y métodos. Se aisló Salmonella spp. de casos clínicos de gastroenteritis (n=110). Se hizo la prueba de sensibilidad antibiótica, así como la serotipificación y la tipificación mediante MLST, y se comparó S. Enteritidis de humanos con la hallada en granjas de gallinas ponedoras y en huevo comercializado (n=6). Resultados. Se aislaron 10 cepas de Salmonella spp. a partir de heces de humanos con gastroenteritis. Se obtuvo una prevalencia de Salmonella spp. de 9,09%, y se identificaron los serotipos S. Enteritidis (n=4), S. Typhymurium (n=2), S. Newport (n=1), S. Grupensis (n=1), S. Uganda (n=1) y S. Braenderup presentes en pacientes con gastroenteritis. Mediante la MLST, se comprobó que un tipo de secuencia común (ST11) de S. Enteritidis estuvo presente en todas las tres fuentes y presentó el mismo patrón de resistencia antibiótica. Conclusión. Salmonella Enteritidis ST11 constituye un vínculo entre el consumo y la manipulación de huevos contaminados, y la gastroenteritis en humanos en Ibagué. Se requieren estudios complementarios para conocer si otros serovares de Salmonella aislados de carne de pollo cruda también se asocian con la gastroenteritis en humanos.

Desenvolvimento e caracterização de nanocápsulas poliméricas contendo carvacrol para inibição de Salmonella enteritidis / Development and characterization of polymeric nanocapsules containing carvacrol for inhibition from Salmonella enteritidis

Avaliou-se caracterização físico-química, ação bactericida e estabilidade de nanocápsulas poliméricas de Eudragit contendo carvacrol preparadas utilizando técnica de deposição interfacial do polímero pré-formado. As nanocápsulas apresentaram diâmetro médio de 146 nm, PDI de 0,181 e potencial zeta de + 23,44 mV e a concentração bactericida mínima necessária para inativar Salmonella Enteritidis foi de 0,331 mg/mL. A solução contendo nanocápsulas manteve suas características físico-químicas e atividade bactericida inalteradas durante os 45 dias do teste de estabilidade, demonstrando características promissoras para o desenvolvimento de um sanitizantes para uso em indústria produtora de ovos e frigorífico de aves.

Increasing prevalence and dissemination of invasive nontyphoidal Salmonella serotype Typhimurium with multidrug resistance in hospitalized patients from southern Brazil

ABSTRACT Introduction: Nontyphoidal Salmonella serotypes are the main cause of human food-borne infection, including several hospitalization cases in the developing countries. Aim: To detect the main serotypes and to characterize the antibiotic resistance of human non-enteric and enteric nontyphoidal Salmonella from clinical isolates in Brazil. Methods: Salmonella serotypes were identified by microbiological and molecular methods. Susceptibility testing to antibiotics was performed by agar disk diffusion. Real-time PCRs were carried out for the detection of the genus Salmonella as well as serotypes Typhimurium and Enteritidis. Results: A total of 307 nontyphoidal Salmonella were isolated from 289 different patients in a reference laboratory (LACEN-RS) from Southern Brazil in a six-year period (2010-2015). There were 45 isolates from emerging cases and 244 from sporadic cases in hospitalized patients. Non-enteric isolates were detected in 42.6% of the patients from sources such as urine, blood and other clinical fluids. Serological and PCR-specific tests demonstrated that Typhimurium (48.4%) and Enteritidis (18.3%) were the most frequent serotypes. Typhimurium isolates were generally resistant to three or more antibiotic classes, while Enteritidis isolates to one or two classes. Typhimurium was the most frequent serotype in all samples (48.4%), mainly among the hospitalized patients (55.6%), and presented the highest rates of multidrug resistance (59.3% of the isolates of this serotype). Further, the prevalence of this serotype increased along the years of the study in comparison to other nontyphoidal Salmonella serotypes. Conclusion: Greater public health attention should be given to prevent salmonellosis in the community and in hospital settings to reduce the rates of Typhimurium strains with multidrug resistance.

The sensitivity of bacterial foodborne pathogens to Croton blanchetianus Baill essential oil

The aim of this study was to assess the activity of essential oil extracted from the leaves of C. blanchetianus Baill, popularly known as "marmeleiro", in inhibiting the growth and survival of pathogenic microorganisms in food by determining their survival in vitro and by observing the behaviour of Listeria monocytogenes inoculated into a food model (meat cubes) that was stored at refrigeration temperature (7 ± 1 ºC) for 4 days. The results indicated a bactericidal effect against Aeromonas hydrophila and Listeria monocytogenes and bacteriostatic action against Salmonella Enteritidis. A bacteriostatic effect on meat contaminated with L. monocytogenes was found for all concentrations of essential oils tested. These results showed that essential oil from the leaves of C. blanchetianus Baill represents an alternative source of potentially natural antimicrobial agents that may be used as a food preservative.

Assessing the growth and recovery of Salmonella Enteritidis SE86 after sodium dichloroisocyanurate exposure

The objective of the present study was to assess the growth and the recovery of Salmonella (S.) Enteritidis SE86 in different diluents, culture media and using different plating methods after the exposure to 200 mg/kg sodium dichloroisocyanurate (NaDCC). Before and after NaDCC exposure, SE86 was cultured at 30 °C and 7 °C in the following diluents: Peptone water (P), Saline solution (SaS), Peptone water+Saline solution (P+SaS), Peptone water+Tween 80+Lecithin+Sodium thiosulfate (P+N) and Saline solution+Tween 80+Lecithin+Sodium thiosulfate (SaS+N). The SaS diluent was chosen because it was able to maintain cells viable without growth and was further used for plating SE86 on non selective medium (Tryptic Soy Agar-TSA) and on selective media (Mannitol Lysine Crystal Violet Brilliant Green Agar-MLCB; Brilliant Green Agar-BGA; Salmonella Shigella Agar-SS and Xylose Lysine Dextrose-XLD). The Thin Agar Layer method (TAL) i.e., selective media overlayed with non selective TSA was also evaluated. Results indicated that SE86 not exposed to NaDCC was able to grow in P, P+N, SaS+N and P+SaS, but not in SaS, that was able to maintain cells viable. SE86 exposed to NaDCC demonstrated similar counts after dilution in SaS and the plating on non selective TSA, selective media MLCB, BGA, SS and XLD and on TAL media. SE86, S. Typhimurium and S. Bredeney, exposed or not exposed to NaDCC, showed no significant differences in counts on TSA, XLD and XLD overlayed with TSA, suggesting that all those media may be used to quantify NaDCC-exposed Salmonella by plating method.

Antimicrobial activity of yerba mate (Ilex paraguariensis St. Hil.) against food pathogens / Antimicrobial activity of yerba mate (Ilex paraguariensis St. Hil.) against food pathogens.

Yerba mate (Ilex paraguariensis St. Hil.) has been studied for its important biological activities mainly attributed to phenolic compounds. This study evaluated the antimicrobial activity of methanolic and ethanolic extracts of yerba mate against food pathogens, such as Staphylococcus aureus, Listeria monocytogenes, Salmonella Enteritidis and Escherichia coli through minimum inhibitory (MIC) and bactericidal (MBC) concentrations, in addition to the determination of chemical composition by gas chromatography with mass spectrometry (GC-MS) and phenolic content. The most effective extract had its activity evaluated under different pH conditions by growth curve analysis. All microorganisms except E. coli were inhibited. The ethanolic extract showed the lowest MIC/MBC (0.78/0.78 mg/ml), the highest phenolic content (193.9 g.GAE/kg) and the presence of chlorogenic acid derivatives, especially 3-O-caffeoylquinic and caffeic acid. This extract was able to inhibit microbial growth at pH 7 and 8.

Recurrent meningitis due to Salmonella enteritidis: A case report from Kashmir India.

Recurrent bacterial meningitis in children is potentially life-threatening and induces psychological trauma to the patients through repeated hospitalization. Here we report a case of recurrent meningitis in a one month old baby. The CSF and blood culture grew Salmonella enteritidis. Injection ciprofloxacin and ceftriaxone were given for 3 weeks. Baby became symptomatically better and was afebrile at discharge. Twenty eight days after discharge baby got readmitted with complaints of fever and refusal of feeds. Blood and CSF culture again showed growth of Salmonella enteritidis. Physicians should be educated about the possibility of recurrence which may occur days or even weeks after apparent successful antibiotic treatment.

Prevalence and antimicrobial resistance of Salmonella in chicken carcasses at retail in 15 Brazilian cities / Prevalencia y resistencia a los antimicrobianos de Salmonella en polloscongelados de venta al por menor en 15 ciudades del Brasil

Objetivo. Describir la prevalencia y la resistencia a los antibióticos de Salmonella spp. en canales de pollo congeladas de venta al por menor en 15 ciudades del Brasil. Métodos. Entre septiembre del 2004 y julio del 2006 se llevó a cabo un estudio descriptivo de los datos del Programa Nacional Brasileño de Vigilancia de la Prevalenciade la Resistencia Bacteriana en el Pollo (PREBAF). Durante el programa serecolectaron canales de pollo en 15 capitales estatales del Brasil, en las cinco regiones geográficas del país. Para aislar Salmonella spp. e identificar los serotipos, se usaron las técnicas convencionales. Para evaluar la resistencia frente a 18 antibióticos, se usó el método de la concentración inhibitoria mínima. Resultados. En las 2 679 canales de pollo examinadas, la prevalencia de Salmonella spp. fue de 2,7% (amplitud, 0,0%–8,9%). El 50,6% de las muestras positivas provinieron del estado de São Paulo. Se identificaron 18 serotipos. Los más frecuentes fueron Salmonella Enteritidis (48,8%), Salmonella Infantis (7,6%), Salmonella Typhimurium (7,2%) y Salmonella Heidelberg (6,4%). Las 250 cepas evaluadas fueron resistentes auno o más antibióticos, y 133 (53,2%) fueron multirresistentes (≥ 3 clases de antibióticos). Salmonella Heidelberg fue resistente a la ceftriaxona (75,0%) y al ceftiofur (43,8%). Conclusiones. La prevalencia de Salmonella spp. en este estudio fue relativamente baja. Sin embargo, hubo una proporción elevada de cepas multirresistentes, inclusivea las cefalosporinas de tercera generación usadas para tratar la salmonelosis invasora. Los resultados confirman la relevancia del programa PREBAF, el cual se recomienda mejorar, por ejemplo, mediante un análisis oportuno de los datos. También es necesario revisar los límites permitidos de Salmonella spp. en el pollo que se vende al por menor en el Brasil.

Objective. To describe the prevalence and antimicrobial resistance of Salmonella spp. in frozen chicken carcasses at retail from 15 Brazilian cities. Methods. A descriptive study of data from the Brazilian National Program for Monitoring the Prevalence of Bacterial Resistance in Chicken (PREBAF) was conducted from September 2004 to July 2006. The program collected chicken carcasses in 15 state capitals of Brazil inthe five geographic regions of the country. Standardized methodologies were used to isolate Salmonella spp. and identify serotypes. The minimal inhibitory concentration method wasused to test resistance to 18 antimicrobials. Results. In 2 679 carcasses examined, the prevalence of Salmonella spp. was 2.7% (range0.0%–8.9%). São Paulo State produced 50.6% of positive samples. Eighteen serotypes were identified. The most frequently occurring were Salmonella Enteritidis (48.8%), Salmonella Infantis (7.6%), Salmonella Typhimurium (7.2%), and Salmonella Heidelberg (6.4%). All 250 strains tested were resistant to one or more antibiotics, and 133 (53.2%) were multidrug resistant (≥ 3 classes). S. Heidelberg was resistant to ceftriaxone (75.0%) and to ceftiofur (43.8%).Conclusions. The prevalence of Salmonella spp. found in this study was relatively low. However, there were a high proportion of multidrug-resistant strains, including thirdgenerationcephalosporins used to treat invasive salmonellosis. The results confirm the relevance of the PREBAF program. It is recommended that PREBAF be improved, including a timely data analysis. A review of permitted limits for Salmonella spp. in retail chicken in Brazil is also needed.

Serovariedades y patrones de susceptibilidad a los antimicrobianos de cepas de Salmonella aisladas de alimentos en Cuba / Serotypes and antimicrobial susceptibility patterns of Salmonella strains isolated from food in Cuba

The serotypes of 178 isolates of Salmonella enterica taken from food in different regions of Cuba between January 2008 and December 2009 were identified, and the antimicrobial susceptibility pattern of 100 selected isolates was determined by stratasampling. A total of 20 Salmonella serotypes were identified, with a predominance of S. Enteritidis (23%), S. Agona (13.5%), and S. London (11.2%). Of all the strains, 75%were resistant or presented intermediate resistance to at least one of the drugs tested, in the following order: tetracycline (70.7%), ampicillin (22.7%), and nalidixic acid (14.7%). Ten different resistance patterns were identified. The most frequent patternscorresponded to strains that were either drug-resistant or had intermediate resistance (89.3%). Three strains (identified as S. Infantis, S. Derby, and S. Enteritidis) were multiresistant, and one of them, S. Enteritidis, was not sensitive to either nalidixic acid or ciprofloxacin. To control salmonellosis, the importance of maximizing integrated health surveillance is emphasized.

Se describen los serotipos de 178 cepas de Salmonella enterica aisladas de alimentos en diferentes regiones de Cuba entre enero de 2008 y diciembre de 2009, y el patrón de susceptibilidada los antimicrobianos de 100 aislados seleccionados mediante muestreo por estratos. Se identificaron 20 serovariedades de Salmonella entre las que predominaron S. Enteritidis (23%);S. Agona (13,5%) y S. London (11,2%). Del total, 75% de las cepas fueron resistentes o presentaronresistencia intermedia a al menos uno de los fármacos probados, en el siguiente orden, según su frecuencia: tetraciclina (70,7%); ampicilina (22,7%) y ácido nalidíxico (14,7%). Seidentificaron 10 patrones de resistencia diferentes y predominaron las cepas resistentes o con resistencia intermedia a un fármaco (89,3%). Tres cepas (S. Infantis, S. Derby y S. Enteritidis)fueron multirresistentes y una, de S. Enteritidis, dio un resultado no sensible al ácido nalidíxico y la ciprofloxacina. Se destaca la necesidad de extremar la vigilancia sanitaria integrada en el país para el control de la salmonelosis.

Antibacterial effect (in vitro) of Moringa oleifera and Annona muricata against Gram positive and Gram negative bacteria / Efeito antibacteriano (in vitro) de Moringa oleifera (moringa) e Annona muricata (graviola) frente a bactérias Gram-negativas e Gram-positiva

Antibacterial effects of aqueous and ethanolic extracts of seeds of moringa (Moringa oleifera) and pods of soursop (Annona muricata) in the concentration of 1:5 and 1:10 in volumes 50, 100, 150 and 200 µL were examined against Staphylococcus aureus, Vibrio cholerae, Escherichia coli (isolated from the organism and the aquatic environment) and Salmonella Enteritidis. Antibacterial activity (inhibition halo > 13 mm) against S. aureus, V. cholerae and E. coli isolated from the whiteleg shrimp, Litopenaeus vannmaei, was detected in aqueous and ethanolic extracts of moringa. E. coli isolated from tilapiafish, Oreochromis niloticus, was sensitive to the ethanolic extract of moringa. The aqueous extracts of soursop showed an antibacterial effect against S. aureus and V. cholerae, but the antibacterial activity by the ethanol extracts of this plant was not demonstrated.

Para avaliação do efeito bactericida frente à Staphylococcus aureus, Vibrio cholerae, Escherichia coli (isolada de pescados e ambiente aquático) e Salmonella Enteretidis, foram testados extratos aquosos e etanólicos de sementes de moringa (Moringa oleifera) e casca de graviola (Annona muricata) na concentração de 1:5 e 1:10, nos volumes de 50, 100, 150 e 200 µL. Os resultados mostraram efeito antibacteriano (halo de inibição > 13mm) dos extratos aquosos e etanólicos de moringa frente a S. aureus, V. cholerae e E. coli isoladas de camarão cinza Litopenaeus vannmaei. A cepa de E. coli isolada do pescado Oreochromis niloticus apresentou sensibilidade frente ao extrato etanólico de moringa. Os extratos aquosos de graviola apresentaram efeito bactericida frente a S. aureus e V. cholerae, entretanto, os extratos etanólicos dessa planta não mostraram atividade antibacteriana.

Evaluación del efecto del cultivo probiótico Lactobacillus rhamnosus adicionado a yogurt natural y con probi6ticos comerciales sobre poblaciones de Staphylococcus aureus, Escherichia coli O157: H7, Listeria monocytogenes y Salmonella enteritidis / Evaluation of the effect of Lactobacillus rhamnosus probiotic culture added to yogurt over Staphylococcus aureus, Escherichia coli O157: H7, Listeria monocytogenes and Salmonella enteritidis populations

Se evaluó el efecto de diferentes tipos de cultivos probióticos en yogurt sobre poblaciones conocidas de Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes y Salmonella enteritidis. Los tres tipos diferentes de yogurt comercial utilizados fueron: sin probióticos adicionados, con probióticos CHR HANSEN® (Lactobacillus casei CRL_431 y L. acidophilus CRL_730) y otro con los mismos probióticos mencionados anteriormente, adicionado con cultivo de Lactobacillus rhamnosus (LR-35). Se inoculó aproximadamente 109 UFC/mL de cada bacteria potencialmente patógena en los diferentes tipos de yogurt, se mantuvo en refrigeración a 4ºC durante la vida útil de cada uno de estos alimentos (aproximadamente 30 días) y se realizó un recuento bacteriano cada cuatro días incluyendo el mismo día de la inoculación. Los resultados obtenidos demuestran que, existe diferencia en cuanto a inhibición entre los yogures sin probióticos y el yogurt comercial con probióticos, observándose un efecto inhibitorio evidente, por parte del segundo sobre las poblaciones de S. aureus, E. coli O157:H7 y L. monocytogenes. Con respecto a los yogures comerciales con probióticos más L. rhamnosus, no se observó alguna diferencia con respecto al efecto inhibitorio que poseen los yogures con probióticos L. casei y L. acidophilus . En los yogures en que se evaluó S. enteritidis se obtuvo la muerte de ésta al cabo de cuatro días. El presente estudio confirma el efecto antagónico que poseen los cultivos probióticos sobre bacterias potencialmente patógenas para el ser humano y animales que pueden estar contenidas en los alimentos.No obstante, el uso del probiótico Lactobacillus rhamnosus no ejerce un efecto inhibitorio adicional.

The effect of different types of probiotics present in yogurt over known populations of Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enteritidis was evaluated. The three types of yogurt used were: without added probiotics, with added probiotics (Lactobacillus casei CRL_431 and L. acidophilus CRL_730 CHR HANSEN®) and another one with the same probiotics mentioned above and Lactobacillus rhamnosus (LR-35) culture. About 109 CFU/ mL of each potentially pathogenic bacteria was added to each type of yogurt tested, and kept in refrigeration at 4ºC during its shelf life, about 30 days. Bacterial count was done the initial day and every four days. Results obtained show that there is a difference in the inhibition between yogurts without added probiotics and the commercial yogurt with added probiotics; there is a clear inhibitory effect of the last one over S. aureus, E coli O157:H7 and Listeria monocytogenes. The yogurt with added probiotics and L. rhamnosus did not show any additional inhibitory effect over the bacteria tested when compared with the yogurt with added probiotics. S. enteritidis could not be evaluated because it was not detectable in any yogurt samples evaluated four days after its inoculation. This study confirms the antagonic effect of probiotic cultures over potentially pathogenic bacteria for human beings and animals that may be present in food. Nevertheless, the use of L. rhamnosus did not produce any additional inhibitory effect.

Analysis of Salmonella enterica serotype Enteritidis isolated from human and chickens by repetitive sequence-PCR fingerprinting, antibiotic resistance and plasmid profiles

A total of 22 Salmonella enterica serotype Enteritidis (S. Enteritidis) strains isolated from human and chicken were subjected to DNA fingerprinting by repetitive sequence PCR using ERIC and BOX primers, antibiotic resistance and plasmid patterns. Both ERIC and BOX PCR amplification data revealed a highly genetic homogeneity between isolates from human and chicken except one isolate, which originated from chicken and showed a different DNA band pattern from others. Eleven of 22 S. Enteritidis isolates (50%) were resistant to more than one antibiotics and characterized by 5 resistance patterns. The most common pattern was penicillin resistant (63.6%). Only one isolate from chicken showed a multiple drug resistance patterns to 4 antibiotics. All 22 S. Enteritidis isolates harbored more than two plasmids with eight different plasmid profiles including two to six plasmids with approximate molecular size ranging from 1.9 to 21 kb. A band of 15 kb size was detected in all isolates tested, however, the band sizes smaller than 15 kb were found only in isolates from chicken.

Antibacterial effects of Carica papaya fruit on common wound organisms

The purpose of the study was to investigate antibacterial activity of ripe and unripe Carica papaya on selected micro-organisms. Cultures of micro-organisms were routinely maintained in nutrient agar slants at 4 degrees C. Extracts of immature, mature and ripe Carica papaya fruit were obtained by separately grinding factions of the epicarp, endocarp and seeds and filtering them through gauze. Sensitivity tests were conducted by adding 0.06 ml of extract to agar wells (6 mm diameter) prepared from 20 ml agar seeded with 10(6) cells/ml suspension of one of the eight organisms per plate. The inoculated plates were allowed to equilibrate at 4 degrees C for 1 hour, incubated at 37 degrees C for 24 hours, and zones of inhibition measured in millimetres. Anti-bacterial activity was expressed in terms of the radius of zone of inhibition. Seed extracts from the fruit showed inhibition in the following order: B cereus > E coli > S faecalis > S aureus > P vulgaris > S flexneri. No significant difference was found in bacterial sensitivity between immature, mature and ripe fruits. No inhibition zone was produced by epicarp and endocarp extracts. Carica papaya seeds contain anti-bacterial activity that inhibits growth of gram-positive and gram-negative organisms. Observed activity was independent of stage of fruit maturity. Carica papaya has antibacterial effects that could be useful in treating chronic skin ulcers to promote healing

Susceptibility patterns and serotypes of non-typhoidal salmonella in Trinidad

To study the serotype distribution of non-typhoidal salmonella isolated from clinical specimens and to evaluate their susceptibility patterns to the most commonly prescribed antimicrobial agents used in this region. A retrospective study during the period 1993- 1999 was carried out at the Eric Williams Medical Sciences Complex Microbiology Laboratory, a teaching hospital in the northwestern part of Trinidad. Strains of non-typhoidal salmonella were serogrouped with polyvalent Salmonella O antiserum and sent to the local Public Health Laboratory for confirmation and further serotyping. A total of 412 strains of non-typhoidal salmonella were serotyped. Of the 13 serotypes, Salmonella enteritidis was the most prevalent 57%, followed by Salmonella typhimurium, 25%, Salmonella virchow 5% and Salmonella heidelberg, 4%. Three hundred and sixty-two [87.5%] non-typhoidal salmonella were isolated from stool, 38 [9%] from blood, 8 [2%] from urine and 4 about 1% from infected wounds. Of the 13 serotypes only Salmonella enteritidis, Salmonella typhimurium, Salmonella virchow and Salmonella heidelberg were simultaneously isolated from blood and stool. One serotype, Salmonella aberdeen, was encountered for the first time in 1993. All isolates were fully sensitive to chloramphenicol, gentamicin, cefuroxime and ceftrioxone. Resistance to ampicillin, augmentin and co-trimoxazole was less than 4%. One third of all non-typhoidal salmonella isolates were resistant to tetracyclines. The most prevalent serotypes were Salmonella enteritidis and Salmonella typhimurium which accounted for 82% of all isolates. The prevalence of resistance of non-typhoidal salmonella to antibiotics was very low [5%]. Therefore, due to this low prevalence of resistance, we did not provide details of resistance in relation to serotype. However, it was observed that of the 137 non-typhoidal salmonella resistant to tetracycline, more than 80% were Salmonella enteritidis and Salmonella typhimurium strains. Of the 9 antibiotics, tetracycline was the only drug to which one-third of the non-typhoidal salmonella were resistant. Due to the risk of resistance continued surveillance of susceptibility patterns of non-typhoidal salmonella to antibiotics must be maintained and encouraged

Immunopharmacological activity of polysaccharide from the pericarb of mangosteen garcinia: phagocytic intracellular killing activities.

Polysaccharides from the pericarbs of mangosteen, Garcinia mangostana Linn., was obtained by treating the dried ground pericarbs with hot water followed by ethanol precipitation (M fraction). The extract was fractionated by anion exchange chromatography on a DEAE-cellulose column as MDE1-5 fractions. The fractions of MDE3 and MDE4 composed of mainly D-galacturonic acid and a small amount of neutral sugar (L-arabinose as the major one and L-rhamnose and D-galactose as the minor ones) were studied for immunopharmacological activities by phagocytic test to intracellular bacteria (Salmonella enteritidis) and nitroblue tetrazolium (NBT) and superoxide generation tests. The results showed that the number of S. enteritidis in cultured monocyte with extract of pericarb of mangosteen (MDE3) was killed. Activating score (mean +/- SD) of NBT test of 100 polymorphonuclear phagocytic cells were 145 +/- 78, 338 +/- 58, 222 +/- 73, 209 +/- 77, 211 +/- 63, 372 +/- 19, 369 +/- 20, 355 +/- 34 in normal saline control, phorbol myristate acetate (PMA), MDE3, MDE4, indomethacin (I), PMA + MDE3, PMA + MDE4 and PMA + I, respectively. Superoxide generation test was also done by color reduction of cytochrome c. Both MDE3 and MDE4 stimulate superoxide production. The number of S. enteritidis in cultured monocyte with extract of pericarb of mangosteen was killed. This paper suggests that polysaccharides in the extract can stimulate phagocytic cells and kill intracellular bacteria (S. enteritidis).

An institutional outbreak of Salmonella enteritidis in Singapore.

A large outbreak of food poisoning occurred in Singapore in March 1995 when a total of 188 inmates in an institution was taken ill. Salmonella enteritidis was isolated from the stool cultures of 35 inmates (16 symptomatic and 19 asymptomatic). All the isolates were of the serotype profile 0:1, 9, 12 and H:g, m (antigen phase I); all were sensitive to ampicillin, ceftriaxone, chloramphenicol, co-trimoxazole and ciprofloxacin. Plasmid profile analysis and restriction enzyme fragmentation patterns (REFPs), as generated with EcoRI and HindIII, of a 60 kb plasmid obtained from these isolates were all identical, confirming that the outbreak resulted from a single source of infection. Stratified statistical analysis of food-specific attack rates strongly implicated imported canned luncheon pork consumed by the inmates on 26 March 95 as the single most probable cause of the food poisoning [p < 10(6), Mantel-Haenszel weighted odds ratio (OR) = 14.33; 95% confidence interval (CI) = 6.20-33.15]. The median incubation period of this outbreak was 19.3 hours and the median duration of illness was three days. The outbreak was rapidly brought under control through prompt implementation of epidemic control measures which comprised active search for diarrheal cases, rectal swabbing of asymptomatic inmates, isolation of those found to be infected, and maintenance of a high standard of personal, food and environmental hygiene.

Salmonella group-E (Senftenberg) lung abscess: a case report.

A male patient presented with complaints of fever, cough with expectoration, burning micturition and 5-6 semisolid motions per day for the past 6 days. Skiagram chest (PA view) revealed lung abscess in the left mid zone. There was no improvement, symptomatically and radiologically, after an empirical course of antibiotics (IV ampicillin and gentamycin). Sputum, urine and stool cultures grew salmonella group E organisms sensitive only to cefotaxime. The patient was treated with IV cefotaxime and responded well clinically, radiologically and bacteriologically.

Resistencia antimicrobiana actual de Salmonella typhy, Salmonella enteritidis y shigella sp / Present antimicrobial resistance to Salmonella typh, Salmonella enteritidis y Shigella sp

Mediante el método de dilución en placa, se probó la sensibilidad a ampicilina, cloranfenicol, trimetoprim-sulfametoxazol (TMP/SMX), furazolidona y cefotaxima, en 305 cepas de Salmonella typhi, 358 cepas de Salmonella enteritidis y 187 cepas de Shigella sp obtenidas de aislamientos clínicos en el Hospital de Pediatría del Centro Médico Nacional, de 1982 a 1985. En 212 cepas se obtuvo además la concentración mínima inhibitoria (CMI) y se calculó la CMI50 la CMI90 y el porcentaje acumulado de acuerdo a la CMI. La resistencia de S. typhi fue de 4.6% para el cloranfenicol, del 2.6% para furazolidona, del 9.4% para ampicilina y del 16.3% para TMP/SMX. La resistencia encontrada para S. enteritidis fue muy elevada (20 a 50%) para todos los antibióticos, excepto para cefotaxima). Aproximadamente un 30% de las cepas de Shigella fueron resistentes a la ampicilina, cloranfenicol y TMP/SMX y un 20% para furazolidona. Sólo se encontró una cepa de cada género resistente a cefotaxima. Se considera que el cloranfenicol continúa siendo el antimicrobiano de elección para la fiebre tifoidea y la furazolidona es la mejor alternativa. Para las infecciones extraintestinales por S. enteritidis es conveniente contar siempre con el antibiograma y en tanto, se puede iniciar con TPM/SMX. Para la diarrea moderada a grave por Shigella, iniciar con ampicilina y cambiar a TMP/SMX. De acuerdo a la evolución clínica y al resultado del antibiograma. Aún cuando la sensibilidad "in vitro" de cefotaxima fue muy buena, se deben de realizar estudios clínicos prospectivos para demostrar su utilidad terapéutica en las infecciones causadas por estos gérmenes