Detection of Oxacillinase Genes that confers Carbapenem Resistance in Acinetobacter Baumannii, in Hospital Acquired Infections.

INTRODUCTION : Acinetobacter calcoaceticus-baumannii is a non fermenting gram negative bacilli or cocco bacilli belonging to the family Moraxellaceae. It is a ubiquitous organism found in soil, sewage, and dry surfaces. They can be readily isolated from areas of moist skin such as toe webs, groin, and the axilla. The organism can be identified from hospital equipment such as ventilators, curtains, telephones, door handles. It was until recently, dismissed as a non pathogen, contaminating clinical specimens. Of late the organism has been recognized as a nosocomial pathogen and has been, increasingly so, in patients admitted in intensive care units, on mechanical ventilation and on central venous catheters. It has emerged as a leading cause of Ventilator Associated pneumonia (VAP). The organism has low virulence potential, but with the emergence of multidrug and pan drug resistant strains, this organism has emerged as a leading cause of mortality, morbidity, and increased hospital cost and duration of hospitalization. In the year 1984, Acinetobacter spp. was classified in the family Neisseriaceae, but more recently the molecular taxonomic studies have resulted in the reclassification of the organism in the new family of Moraxellaceae in 1991. AIM & OBJECTIVES : Aim: To detect the various genes those encodes for carbapenem resistance in clinical isolates of A.baumannii and ascertain the molecular marker for rapid detection for the same. Objectives: 1. To identify A.baumannii phenotypically. 2. To evaluate OXA-51 for identification of A.baumannii. 3. To determine the gene encoding for carbapenem resistance (OXA-51 and OXA-23). 4. To determine the prevalent antimicrobial susceptibility profile among our study isolates. 5. To determine the susceptibility of carbapenem resistant A.baumannii to Tigecycline by disc diffusion method. 6. To determine the baseline MIC value for drugs of renewed interest (Polymyxins, Sulbactam) against carbapenem resistant nosocomial A.baumannii. 7. To investigate for presence of other resistance genes in representative isolates. 8. To correlate the outcome in patients infected with carbapenem and Tigecycline Resistant strains. 9. To correlate clinically the outcome using Clinical Pulmonary Infection Score (CPIS) and Charlson Co-morbidity Index (CCI). MATERIALS AND METHODS : A total of 100 isolates of Acinetobacter calcoaceticus-baumannii complex were enrolled in this study. The isolates were from various clinical materials sent to the Clinical Microbiology department for bacteriological culture, biochemical identification, and antibiotic susceptibility testing. Isolates included in this study were obtained from blood, sputum, Endo tracheal aspirate, tracheal aspirate, central lines, cerebrospinal fluid, wound swabs, infected tissue. The isolates were collected form patients, who were diagnosed to have nosocomial infections defined as infections developing 48 hours after hospital admission. Samples collected for a period of 1 year, i.e. samples coming during the time period from, December 2006 to December 2007 were included in this study. CONCLUSIONS : Conclusions and summary The total number of nosocomial A.baumannii isolates included in this study was one hundred. 78% of the isolates included in this study were isolated from nosocomial pneumonia. This indicates that A. baumannii is a leading cause of nosocomial pneumonia. The resistance to β-lactam agents was 100%, to amino glycosides and fluoroquinolones was 85% and to the β-lactam +β-lactamase inhibitor combination was 79%. The number of PDR A.baumannii was 57% and MDR A.baumannii was 43%. The number of isolates being resistant to so many anti microbial agents is indeed concerning. Efficacy of the newer drug being advocated as a treatment option for carbapenem resistant A.baumannii - Tigecycline was evaluated in our study isolates. None of the isolates tested, were susceptible to Tigecycline with only seven of the isolates being intermediately susceptible. The lack of standard break points for defining susceptibility or resistance has also partially lead to varied results across the world

Determinants and impact of giardia infection in the first 2 years of life in the MAL-ED birth cohort

Background: Giardia are among the most common enteropathogens detected in children in low-resource settings. We describe here the epidemiology of infection with Giardia in the first 2 years of life in the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED), a multisite birth-cohort study.Methods: From 2089 children, 34916 stool samples collected during monthly surveillance and episodes of diarrhea were tested for Giardia using an enzyme immunoassay. We quantified the risk of Giardia detection, identified risk factors, and assessed the associations with micronutrients, markers of gut inflammation and permeability, diarrhea, and growth using multivariable linear regression.Results: The incidence of at least 1 Giardia detection varied according to site (range, 37.7%-96.4%) and was higher in the second year of life. Exclusive breastfeeding (HR for first Giardia detection in a monthly surveillance stool sample, 0.46 [95% confidence interval (CI), 0.28-0.75]), higher socioeconomic status (HR, 0.74 [95% CI, 0.56-0.97]), and recent metronidazole treatment (risk ratio for any surveillance stool detection, 0.69 [95% CI, 0.56-0.84]) were protective. Persistence of Giardia (consecutive detections) in the first 6 months of life was associated with reduced subsequent diarrheal rates in Naushahro Feroze, Pakistan but not at any other site. Giardia detection was also associated with an increased lactulose/mannitol ratio. Persistence of Giardia before 6 months of age was associated with a -0.29 (95% CI, -0.53 to -0.05) deficit in weight-for-age z score and -0.29 (95% CI, -0.64 to 0.07) deficit in length-for-age z score at 2 years.Conclusion: Infection with Giardia occurred across epidemiological contexts, and repeated detections in 40% of the children suggest that persistent infections were common. Early persistent infection with Giardia, independent of diarrhea, might contribute to intestina

Pathogen-specifi c burdens of community diarrhoea in developing countries: a multisite birth cohort study (MAL-ED)

Background Most studies of the causes of diarrhoea in low-income and middle-income countries have looked at severe disease in people presenting for care, and there are few estimates of pathogen-specifi c diarrhoea burdens in the community. Methods We undertook a birth cohort study with not only intensive community surveillance for diarrhoea but also routine collection of non-diarrhoeal stools from eight sites in South America, Africa, and Asia. We enrolled children within 17 days of birth, and diarrhoeal episodes (defi ned as maternal report of three or more loose stools in 24 h, or one loose stool with visible blood) were identifi ed through twice-weekly home visits by fi eldworkers over a follow-up period of 24 months. Non-diarrhoeal stool specimens were also collected for surveillance for months 1–12, 15, 18, 21, and 24. Stools were analysed for a broad range of enteropathogens using culture, enzyme immunoassay, and PCR. We used the adjusted attributable fraction (AF) to estimate pathogen-specifi c burdens of diarrhoea. Findings Between Nov 26, 2009, and Feb 25, 2014, we tested 7318 diarrhoeal and 24 310 non-diarrhoeal stools collected from 2145 children aged 0–24 months. Pathogen detection was common in non-diarrhoeal stools but was higher with diarrhoea. Norovirus GII (AF 5·2%, 95% CI 3·0–7·1), rotavirus (4·8%, 4·5–5·0), Campylobacter spp (3·5%, 0·4–6·3), astrovirus (2·7%, 2·2–3·1), and Cryptosporidium spp (2·0%, 1·3–2·6) exhibited the highest attributable burdens of diarrhoea in the fi rst year of life. The major pathogens associated with diarrhoea in the second year of life were Campylobacter spp (7·9%, 3·1–12·1), norovirus GII (5·4%, 2·1–7·8), rotavirus (4·9%, 4·4–5·2), astrovirus (4·2%, 3·5–4·7), and Shigella spp (4·0%, 3·6–4·3). Rotavirus had the highest AF for sites without rotavirus vaccination and the fi fth highest AF for sites with the vaccination. There was substantial variation in pathogens according to geography, diarrhoea severity, and season. Bloody diarrhoea was primarily associated with Campylobacter spp and Shigella spp, fever and vomiting with rotavirus, and vomiting with norovirus GII. Interpretation There was substantial heterogeneity in pathogen-specifi c burdens of diarrhoea, with important determinants including age, geography, season, rotavirus vaccine usage, and symptoms. These fi ndings suggest that although single-pathogen strategies have an important role in the reduction of the burden of severe diarrhoeal disease, the eff ect of such interventions on total diarrhoeal incidence at the community level might be limited

Epidemiology and Risk Factors for Cryptosporidiosis in Children from 8 Low-income Sites : Results from the MAL-ED Study

Funding Information: The MAL-ED study is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the National Institutes of Health (NIH), and the NIH Fogarty International Center. This work was also supported by the National Institute of Allergy and Infectious Diseases of the NIH (grant numbers K23 AI087910 to P. K. and K23 AI087910 to W. A. P.) and by the Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases Discovery Program (to P. D.).Peer reviewedPublisher PD

Persistence of G10P[11] neonatal rotavirus infections in southern India

BACKGROUND: Neonatal rotavirus infections are predominantly caused by distinct genotypes restricted to this age-group and are mostly asymptomatic. METHOD: Stool samples from neonates admitted for >48 h in neonatal intensive care units (NICUs) in Vellore (2014–2015) and Chennai (2015–2016) in southern India, and from neonates born at hospitals in Vellore but not admitted to NICUs (2015–2016) were tested for rotavirus by ELISA and genotyped by hemi-nested RT-PCR. RESULTS: Of 791 neonates, 150 and 336 were recruited from Vellore and Chennai NICUs, and 305 were born in five hospitals in Vellore. Positivity rates in the three settings were 49.3% (74/150), 29.5% (99/336) and 54% (164/305), respectively. G10P[11] was the commonly identified genotype in 87.8% (65/74), 94.9% (94/99) and 98.2% (161/164) of the neonates in Vellore and Chennai NICUs, and those born at Vellore hospitals, respectively. Neonates delivered by lower segment cesarian section (LSCS) at Vellore hospitals, not admitted to NICUs, had a significantly higher odds of acquiring rotavirus infection compared to those delivered vaginally [p = 0.002, OR = 2.4 (1.4–4.3)]. CONCLUSIONS: This report demonstrates the persistence of G10P[11] strain in Vellore and Chennai, indicating widespread neonatal G10P[11] strain in southern India and their persistence over two decades, leading to interesting questions about strain stability

Determinants and Impact of Giardia Infection in the First 2 Years of Life in the MAL-ED Birth Cohort

Background. Giardia are among the most common enteropathogens detected in children in low-resource settings. We describe here the epidemiology of infection with Giardia in the first 2 years of life in the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED), a multisite birth-cohort stu dy. Methods. From 2089 children, 34 916 stool samples collected during monthly surveillance and episodes of diarrhea were tested for Giardia using an enzyme immunoassay. We quantified the risk of Giardia detection, identified risk factors, and assessed the associations with micronutrients, markers of gut inflammation and permeability, diarrhea, and growth using multivariable linear regression. Results. The incidence of at least 1 Giardia detection varied according to site (range, 37.7%–96.4%) and was higher in the sec - ond year of life. Exclusive breastfeeding (HR for first Giardia detection in a monthly surveillance stool sample, 0.46 [95% confidence interval (CI), 0.28–0.75]), higher socioeconomic status (HR, 0.74 [95% CI, 0.56–0.97]), and recent metronidazole treatment (risk ratio for any surveillance stool detection, 0.69 [95% CI, 0.56–0.84]) were protective. Persistence of Giardia (consecutive detections) in the first 6 months of life was associated with reduced subsequent diarrheal rates in Naushahro Feroze, Pakistan but not at any other site. Giardia detection was also associated with an increased lactulose/mannitol ratio. Persistence of Giardia before 6 months of age was associated with a −0.29 (95% CI, −0.53 to −0.05) deficit in weight-for-age z score and −0.29 (95% CI, −0.64 to 0.07) deficit in length-for-age z score at 2 years. Conclusions. Infection with Giardia occurred across epidemiological contexts, and repeated detections in 40% of the children suggest that persistent infections were common. Early persistent infection with Giardia , independent of diarrhea, might contribute to intestinal permeability and stunted growth

Immune predictors of oral poliovirus vaccine immunogenicity among infants in South India.

Identification of the causes of poor oral vaccine immunogenicity in low-income countries might lead to more effective vaccines. We measured mucosal and systemic immune parameters at the time of vaccination with oral poliovirus vaccine (OPV) in 292 Indian infants aged 6-11 months, including plasma cytokines, leukocyte counts, fecal biomarkers of environmental enteropathy and peripheral blood T-cell phenotype, focused on gut-homing regulatory CD4+ populations. We did not find a distinct immune phenotype associated with OPV immunogenicity, although viral pathogens were more prevalent in stool at the time of immunization among infants who failed to seroconvert (63.9% vs. 45.6%, p = 0.002). Using a machine-learning approach, we could predict seroconversion a priori using immune parameters and infection status with a median 58% accuracy (cross-validation IQR: 50-69%) compared with 50% expected by chance. Better identification of immune predictors of OPV immunogenicity is likely to require sampling of mucosal tissue and improved oral poliovirus infection models

The effect of probiotics and zinc supplementation on the immune response to oral rotavirus vaccine: A randomized, factorial design, placebo-controlled study among Indian infants.

BACKGROUND: Strategies are needed to improve oral rotavirus vaccine (RV), which provides suboptimal protection in developing countries. Probiotics and zinc supplementation could improve RV immunogenicity by altering the intestinal microbiota and immune function. METHODS: Infants 5weeks old living in urban Vellore, India were enrolled in a randomized, double-blind, placebo-controlled trial with a 4-arm factorial design to assess the effects of daily zinc (5mg), probiotic (1010Lactobacillus rhamnosus GG) or placebo on the immunogenicity of two doses of RV (Rotarix®, GlaxoSmithKline Biologicals) given at 6 and 10weeks of age. Infants were eligible for participation if healthy, available for the study duration and without prior receipt of RV or oral poliovirus vaccine other than the birth dose. The primary outcome was seroconversion to rotavirus at 14weeks of age based on detection of VP6-specific IgA at ?20U/ml in previously seronegative infants or a fourfold rise in concentration. RESULTS: The study took place during July 2012 to February 2013. 620 infants were randomized equally between study arms and 551 (88.9%) completed per protocol. Seroconversion was recorded in 54/137 (39.4%), 42/136 (30.9%), 40/143 (28.0%), and 37/135 (27.4%) infants receiving (1) probiotic and zinc, (2) probiotic and placebo, (3) placebo and zinc, (4) two placebos. Seroconversion showed a modest improvement among infants receiving probiotic (difference between groups 1, 2 and 3, 4 was 7.5% (97.5% Confidence Interval (CI): -1.4%, 16.2%), p=0.066) but not zinc (difference between groups 1, 3 and 2, 4 was 4.4% (97.5% CI: -4.4%, 13.2%), p=0.272). 16 serious adverse events were recorded, none related to study interventions. CONCLUSIONS: Zinc or probiotic supplementation did not significantly improve the low immunogenicity of rotavirus vaccine given to infants in a poor urban community in India. A modest effect of combined supplementation deserves further investigation. TRIAL REGISTRATION: The trial was registered in India (CTRI/2012/05/002677)

Impact of maternal antibodies and microbiota development on the immunogenicity of oral rotavirus vaccine in African, Indian, and European infants: a prospective cohort study

Identifying risk factors for impaired oral rotavirus vaccine (ORV) efficacy in low-income countries may lead to improvements in vaccine design and delivery. We measured maternal rotavirus antibodies, environmental enteric dysfunction (EED), and bacterial gut microbiota development among infants receiving two doses of Rotarix in India (n = 307), Malawi (n = 119), and the UK (n = 60), using standardised methods across cohorts. ORV shedding and seroconversion rates were significantly lower in Malawi and India than the UK. Maternal rotavirus-specific antibodies in serum and breastmilk were negatively correlated with ORV response in India and Malawi, and this was mediated partly by a reduction in ORV replication. In the UK, ORV replication was not inhibited despite comparable maternal antibody levels. In both India and Malawi, pre-vaccination microbiota diversity was negatively correlated with ORV immunogenicity, suggesting that high early-life microbial exposure may contribute to impaired vaccine efficacy

Early Life Child Micronutrient Status, Maternal Reasoning, and a Nurturing Household Environment have Persistent Influences on Child Cognitive Development at Age 5 years : Results from MAL-ED

Funding Information: The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the NIH, and the National Institutes of Health/Fogarty International Center. This work was also supported by the Fogarty International Center, National Institutes of Health (D43-TW009359 to ETR). Author disclosures: BJJM, SAR, LEC, LLP, JCS, BK, RR, RS, ES, LB, ZR, AM, RS, BN, SH, MR, RO, ETR, and LEM-K, no conflicts of interest. Supplemental Tables 1–5 and Supplemental Figures 1–3 are available from the “Supplementary data” link in the online posting of the article and from the same link in the online table of contents at https://academic.oup.com/jn/. Address correspondence to LEM-K (e-mail: [email protected]). Abbreviations used: HOME, Home Observation for Measurement of the Environment inventory; MAL-ED, The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project; TfR, transferrin receptor; WPPSI, Wechsler Preschool Primary Scales of Intelligence.Peer reviewe