Antimicrobial resistance (AMR) continues to pose a significant public health problem in terms of mortality and economic loss. Health authorities of several countries including India have formulated action plans for its containment. In this fight against AMR, it is important to realize the contribution by all the following four spheres: humans, animals, food and environment. This review incorporates all the spheres of One Health concept from the Indian perspective. India has one of the highest rates of resistance to antimicrobial agents used both in humans and food animals. The environment, especially the water bodies, have also reported the presence of resistant organisms or their genes. Specific socio-economic and cultural factors prevalent in India make the containment of resistance more challenging. Injudicious use of antimicrobials and inadequate treatment of waste waters are important drivers of AMR in India. Use of sludge in agriculture, improper discard of livestock animals and aquaculture industry are considered AMR contributors in other countries but Indian data regarding these are lacking. Efforts to combat AMR have been initiated by the Indian health authorities but are still at preliminary stages. Keeping in view the challenges unique to India, future directions are proposed.
1 August 2017 in Journal of the Neurological Sciences
Introduction: With the increasing threat of multidrug-resistant organisms, such as Acinetobacter baumannii , the polymyxin class of drugs (colistin and polymyxin B) has become popular in clinical practice. A better understanding of antimicrobial susceptibility testing methods for colistin and polymyxin B is needed for optimal patient management. Materials and Methods: Forty-two carbapenem-resistant A. baumannii isolates were subjected to susceptibility testing for colistin and polymyxin B using the following methods: broth microdilution (BMD) (glass-coated plates [BMD-Gs] and polystyrene plates [BMD-Ps]), agar dilution (AD), E-test ® , Vitek ® , and disk diffusion. Using BMD as the gold standard, comparative analysis between different methods was carried out. Results: With BMD-Gs as reference, reliability was high for BMD-Ps and moderate for AD and Vitek for both the drugs. Similar results were obtained when the BMD-P was used as reference, but drug–polystyrene interaction was observed. Conclusion: Different susceptibility testing methods for polymyxins show great variation in their results and BMD using glass-coated plates can be considered the best candidate for gold standard.
Accurate and rapid identification of dipteran vectors is integral for entomological surveys and is a vital component of control programs for mosquito-borne diseases. Conventionally, morphological features are used for mosquito identification, which suffer from biological and geographical variations and lack of standardization. We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for protein profiling of mosquito species from North India with the aim of creating a MALDI-TOF MS database and evaluating it. Mosquito larvae were collected from different rural and urban areas and reared to adult stages. The adult mosquitoes of four medically important genera, Anopheles, Aedes, Culex and Armigerus, were morphologically identified to the species level and confirmed by ITS2-specific PCR sequencing. The cephalothoraces of the adult specimens were subjected to MALDI-TOF analysis and the signature peak spectra were selected for creation of database, which was then evaluated to identify 60 blinded mosquito specimens. Reproducible MALDI-TOF MS spectra spanning over 2–14 kDa m/z range were produced for nine mosquito species: Anopheles (An. stephensi, An. culicifacies and An. annularis); Aedes (Ae. aegypti and Ae. albopictus); Culex (Cx. quinquefasciatus, Cx. vishnui and Cx. tritaenorhynchus); and Armigerus (Ar. subalbatus). Genus- and species-specific peaks were identified to create the database and a score of > 1.8 was used to denote reliable identification. The average numbers of peaks obtained were 55–60 for Anopheles, 80–100 for Aedes, 30–60 for Culex and 45–50 peaks for Armigeres species. Of the 60 coded samples, 58 (96.67%) were correctly identified by MALDI-TOF MS with a score > 1.8, while there were two unreliable identifications (both Cx. quinquefasciatus with scores < 1.8). MALDI-TOF MS appears to be a pragmatic technique for accurate and rapid identification of mosquito species. The database needs to be expanded to include species from different geographical regions and also different life-cycle stages to fully harness the technique for entomological surveillance programs.
1 May 2016 in The International Journal of Tuberculosis and Lung Disease
Rapid and accurate diagnosis of tuberculous meningitis (TBM) is imperative for the optimal management of patients. Loop-mediated isothermal amplification (LAMP) is a promising nucleic-acid amplification assay, especially for resource-poor, endemic countries. Evaluating LAMP assay using insertion sequence (IS) 6110 and MPB64 targets for the Mycobacterium tuberculosis complex (MTC) for the rapid diagnosis of TBM. Results were compared with culture and the composite reference standard. The LAMP assay was performed using six MTC-specific primers each for IS6110 and MPB64 on the cerebrospinal fluid of 150 TBM patients (50 confirmed, 100 suspected) and 100 non-TBM control subjects. Multitargeted LAMP had a sensitivity and specificity of 96% and 100% for confirmed (50 culture-positive) TBM cases. The sensitivity of IS6110 polymerase chain reaction (PCR), IS6110 LAMP and MPB64 LAMP for probable cases was respectively 70 (70%), 78 (78%) and 82 (82%). In a total of 150 TBM patients, the overall sensitivity of microscopy, IS6110 PCR, IS6110 LAMP, MPB64 LAMP and the multitargeted LAMP was respectively 4%, 74.6%, 82.7%, 86.7% and 88%. The specificity for all was 100%. Six cases were missed by IS6110 LAMP and two cases by MPB64 LAMP. The LAMP assay using two targets is a promising and accurate technique for the rapid diagnosis of TBM.