Kundan Tandel

Emergence of influenza A(H1N1)pdm09 genogroup 6B and drug resistant virus, India, January to May 2015

To investigate the aetiology of the 2015 A(H1N1)pdm09 influenza outbreak in India, 1,083 nasopharyngeal swabs from suspect patients were screened for influenza A(H1N1)pdm09 in the state of Madhya Pradesh. Of 412 positive specimens, six were further characterised by phylogenetic analysis of haemagglutinin (HA) sequences revealing that they belonged to genogroup 6B. A new mutation (E164G) was observed in HA2 of two sequences. Neuraminidase genes in two of 12 isolates from fatal cases on prior oseltamivir treatment harboured the H275Y mutation.

Burden of extensively drug-resistant and pandrug-resistant Gram-negative bacteria at a tertiary-care centre

The emergence of resistance to multiple antimicrobial agents in Gram-negative bacteria is a significant threat to public health, as it restricts the armamentarium of the clinician against these infections. The aim of this study was to determine the burden of extensively drug-resistant (XDR) and pandrug-resistant (PDR) Gram-negative bacteria at a tertiary-care centre. Antimicrobial susceptibility testing of 1240 clinical isolates of Gram-negative bacteria obtained from various clinical samples during the study period was carried out by the Kirby-Bauer disc diffusion method. Minimum inhibitory concentration of all antibiotics including tigecycline and colistin was determined by Vitek-2 automated susceptibility testing system. Out of 1240 isolates of Gram-negative bacteria, 112 isolates (9%) were resistant to all the antibiotics tested by Kirby-Bauer disc diffusion method. This finding was corroborated by Vitek-2. In addition, Vitek-2 found that 67 isolates were resistant to all antibiotics except tigecycline and colistin. A total of 30 isolates were susceptible to only colistin, and four isolates were susceptible to only tigecycline. It was also found that six isolates (excluding five isolates of Proteus spp.) were resistant to both colistin and tigecycline. Thus, 101 (8.1%) out of 1240 isolates were XDR and 11 isolates (0.9%) were PDR. The findings of this study reveal increased burden of XDR and PDR Gram-negative bacteria in our centre. It also highlights the widespread dissemination of these bacteria in the community. This situation warrants the regular surveillance of antimicrobial resistance of Gram-negative bacteria and implementation of an efficient infection control program.

Species distribution and antimicrobial resistance pattern of Coagulase-negative Staphylococci at a tertiary care centre

BACKGROUND Coagulase-negative Staphylococci (CoNS), previously dismissed at contaminants, have now emerged as an important cause of nosocomial infections especially in patients with implants and prosthetic devices. They are a well-known cause of bloodstream infections, urinary tract infections, wound infections, prosthetic valve endocarditis and eye infections. This study was conducted with an aim to identify CoNS at the species level from various clinical samples and determine the antimicrobial resistance pattern of these isolates. METHODS This cross sectional study was carried out from September 2011 to February 2014 in which 150 non-repetitive clinical isolates of CoNS were identified at the species level by conventional phenotypic methods. Complete antimicrobial susceptibility profile was also determined by Kirby Bauer disc diffusion method. Susceptibility testing to vancomycin was done by E-test method. RESULTS Only three species of CoNS were isolated, the most common being Staphylococcusepidermidis (60%) followed by Staphylococcussaprophyticus (27.3%) and Staphylococcushemolyticus (12.7%). Most S. epidermidis were isolated from blood and intravascular catheter tip samples, whereas all S. saprophyticus were isolated from urine samples of female patients. All isolates were found to be resistant to penicillin, but were susceptible to glycopeptides and linezolid and showed variable resistance to fluoroquinolones, aminoglycosides and macrolides. CONCLUSION CoNS are emerging nosocomial pathogens and should not always be overlooked as contaminants. However, growth of CoNS from blood cultures and intravascular catheter tips should be clinically correlated and carefully interpreted. As many CoNS strains exhibit drug resistance, antimicrobial susceptibility profile should be determined prior to treatment of these infections.

Zika virus: A public health threat†

The resurgence of Zika virus as public health emergency of an international concern with increased incidence of microcephaly has drawn attention of scientific community for its detailed understanding with regard to virus evolution, epidemiology, geographical spread, pathogenesis, etc. The scope of the present review is to discuss the detailed updated information in respect of Zika virus evolution since its inception.

Burkholderia cepacia pseudobacteremia traced to contaminated antiseptic used for skin antisepsis prior to blood collection

Background: Burkholderia (previously Pseudomonas) cepacia is a Gram-negative bacillus commonly found in soil and moist environments and capable of surviving and growing in nutrient-poor surroundings. It is a problematic pulmonary pathogen in patients with cystic fibrosis and is associated with a poor prognosis. Small hospital outbreaks are frequent, usually because of a single contaminated source such as disinfectant. Aim: To identify the source and route of infection of B. cepacia grown from 12 patients from a surgical ICU. Methods: We carried out an environmental and epidemiological investigation to identify the source and route of infection. Environmental samples previously reported to be potential reservoirs of B. cepacia were collected and processed. Results: Out of 67 blood samples received in a 2-month period from the ICU (surgical) of a tertiary care centre, B. cepacia was isolated from blood specimens of 12 patients, whereas 34 samples grew organisms other than B. Cepacia, 20 specimens were culture negative. There were no cases of B. Cepacia in the last 1 year before this outbreak. We isolated B. cepacia from the cetrimide + chlorhexidine solution used for skin antisepsis prior to blood collection. Conclusion: B. cepacia has the potential to cause fatal infections and its multidrug resistance makes its presence dangerous in hospital settings. The surveillance of B. cepacia infections should not be neglected, especially in the ICUs. Given the high transmissibility of the microorganism and previous epidemic reports, strict infection control measures should be applied in the case of diagnosis of B. cepacia infection.

Oseltamivir-resistant influenza A(H1N1)pdm09 virus associated with high case fatality, India 2015

Influenza A viruses has been associated with severe global pandemics of high morbidity and mortality with devastating impact on human health and global economy. India witnessed a major outbreak of influenza A(H1N1)pdm09 in 2015. This study comprises detailed investigation of cases died of influenza A(H1N1)pdm09 virus infection during explosive outbreak of 2015, in central part of India. To find out presence of drug resistant virus among patients who died of influenza A(H1N1)pdm09 virus infection and to find out presence of other mutations contributing to the morbidity and mortality. Twenty‐two patients having confirmed influenza A(H1N1)pdm09 infection and subsequently died of this infection along with 20 non fatal cases with influenza A(H1N1)pdm09 infection were included in the study. Samples were investigated through RT‐PCR/RFLP analysis, followed by nucleotide cycle sequencing of whole NA gene for detection of H275Y amino acid substitution in NA gene responsible for oseltamivir drug resistance. Out of 22 fatal cases, 6 (27.27%) were found to harbor oseltamivir resistant virus strains, whereas the H275Y mutation was not observed among the 20 non fatal cases. Amino acid substitution analysis of complete NA gene revealed V241I, N369K, N386K substitution in all strains playing synergistic role in oseltamivir drug resistance. High morbidity and mortality associated with influenza A(H1N1)pdm09 viruses can be explained by presence of drug resistant strains circulating in this outbreak. Presence of Oseltamivir resistant influenza A(H1N1)pdm09 viruses is a cause of great concern and warrants continuous screening for the circulation of drug resistant strains.

Meningitis caused by Lactococcus garvieae

Maj Kundan Tandel*, Maj Puneet Bhatt, Col Praveer Ranjan, Col K.R. Rathi Graded Specialist (Microbiology), DRDE, Gwalior, India Graded Specialist (Microbiology), Command Hospital (Southern Command), Pune 411040, India Senior Advisor (Pathology), Command Hospital (Southern Command), Pune 411040, India Senior Advisor (Path & Neuropath), Command Hospital (Southern Command), Pune 411040, India m e d i c a l j o u r n a l a r m e d f o r c e s i n d i a x x x ( 2 0 1 5 ) x x x – x x x

Simultaneous detection and serotyping of dengue infection using single tube multiplex CDC Dengue Real-Time RT-PCR from India

AbstractFour antigenically different dengue virus serotypes (DENV-1, DENV-2, DENV-3 and DENV-4) are known to cause infections in humans. Some of these are known to cause more severe disease than the others. Chances for developing Dengue hemorrhagic fever-dengue shock syndrome (DHF-DSS) increases significantly with history of previous infection with one of the four serotypes. Therefore, early diagnosis, serotyping and providing early warning of dengue fever epidemics to concerned authorities becomes very important for better patient outcome and to curb the rapid spread in the community. During the 2014 outbreak, a total of 100 samples from suspected cases of dengue were collected. NS1 antigen based rapid test was used for serological diagnosis. Dengue complex one step reverse transcription-polymerase chain reaction was performed to look for presence of viral RNA. Single tube multiplex RT-PCR was also performed to look for infecting serotype. CDC Dengue Multiplex Real Time PCR assay was performed for rapid diagnosis and simultaneous serotyping of the dengue virus. Out of the 100 samples screened, 69 were found to be positive by NS1Ag Rapid test. 34 samples were found positive by dengue consensus RT-PCR assay. 22 samples were found to be positive by single tube Dengue multiplex RT-PCR assay. Serotype DEN-2 was present in maximum numbers followed by DEN-3. 44 samples were found positive by DENV CDC Multiplex Real time PCR assay. DEN-2 was found in maximum numbers followed by DEN-1. Dengue remains to be an important health problem in India and across the globe. Few serotypes of dengue are more dangerous than the others. Rapid diagnosis and serotyping remains the key for better patient management and prevention of disease spreading in the community. Highly sensitive, specific and rapid CDC real time RT-PCR assay was found to be most promising tool among all available molecular diagnostic methods. This will serve a rapid and reliable simultaneous dengue virus detection as well serotyping assay in near future for rapid identification of dengue suspected sample screening.

Emergence of human West Nile Virus infection among pediatric population in Madhya Pradesh, India: TANDEL et al.

Human infections caused by West Nile virus (WNV) mostly remain subclinical and self‐limited. However, nearly 20% infected people suffer from febrile illness and very few of them (<1%) may get neuroinvasive illness. Mortality has been reported among children. India somehow has reported very less number of WNV cases in the past. We collected cerebrospinal fluid (CSF) samples from 75 pediatric age group patients clinically suffering from acute encephalitis syndrome. Three of these samples were positive by reverse transcriptase polymerase chain reaction using pan flavivirus primers. On sequencing of the 212 bp long–amplified fragment, it was found to be WNV belonging to lineage 1. This is probably the first report of WNV causing encephalitis from this central part of India.