Valsan Philip Verghese

Immunogenicity of a single dose of tetravalent meningococcal serogroups A, C, W-135, and Y conjugate vaccine administered to 2- to 10-year-olds is noninferior to a licensed-ACWY polysaccharide vaccine with an acceptable safety profile

Background: Meningococcal disease remains an important cause of invasive bacterial infections in children less than 5 years of age. Immunogenicity and safety of the investigational ACWY vaccine conjugated with tetanus toxoid (ACWY-TT, GlaxoSmithKline Biologicals) were evaluated in 1501 healthy 2- to 10-year-old children in the Philippines, India, Lebanon, and Saudi Arabia. Methods: Children were randomized (3:1) to receive ACWY-TT or licensed tetravalent meningococcal polysaccharide vaccine (Mencevax, GlaxoSmithKline, Men-PS). Diary cards were used to collect solicited symptoms for 4 days after vaccination. Serious adverse events were reported for 6 months. Serum bactericidal activity (rSBA, rabbit complement) was measured before and 1 month after vaccination in the first 75% of subjects enrolled in each country. Results: The statistical criteria for noninferiority in terms of rSBA vaccine responses were reached. Exploratory analyses showed that postvaccination rSBA titers ≥1:8 and ≥1:128 were significantly higher after ACWY-TT than Men-PS for serogroups C, W-135, and Y, and rSBA vaccine responses and geometric mean antibody titers were significantly higher for all 4 serogroups after administration of ACWY-TT. Noninferiority in terms of incidences of grade 3 general symptoms was not demonstrated. ACWY-TT was well tolerated with grade 3 events reported in <1% of subjects per group. No serious adverse events were considered related to vaccination. Conclusion: ACWY-TT was immunogenic in children between 2 to 10 years of age with a clinically acceptable safety profile that resembled licensed Men-PS. These data support a positive benefit/risk ratio for the ACWY-TT vaccine.

Does 3-day course of oral amoxycillin benefit children of non-severe pneumonia with wheeze: a multicentric randomised controlled trial.

Background WHO-defined pneumonias, treated with antibiotics, are responsible for a significant proportion of childhood morbidity and mortality in the developing countries. Since substantial proportion pneumonias have a viral etiology, where children are more likely to present with wheeze, there is a concern that currently antibiotics are being over-prescribed for it. Hence the current trial was conducted with the objective to show the therapeutic equivalence of two treatments (placebo and amoxycillin) for children presenting with non-severe pneumonia with wheeze, who have persistent fast breathing after nebulisation with salbutamol, and have normal chest radiograph. Methodology This multi-centric, randomised placebo controlled double blind clinical trial intended to investigate equivalent efficacy of placebo and amoxicillin and was conducted in ambulatory care settings in eight government hospitals in India. Participants were children aged 2–59 months of age, who received either oral amoxycillin (31–54 mg/Kg/day, in three divided doses for three days) or placebo, and standard bronchodilator therapy. Primary outcome was clinical failure on or before day- 4. Principal Findings We randomized 836 cases in placebo and 835 in amoxycillin group. Clinical failures occurred in 201 (24.0%) on placebo and 166 (19.9%) on amoxycillin (risk difference 4.2% in favour of antibiotic, 95% CI: 0.2 to 8.1). Adherence for both placebo and amoxycillin was >96% and 98.9% subjects were followed up on day- 4. Clinical failure was associated with (i) placebo treatment (adjusted OR = 1.28, 95% CI: 1.01 to1.62), (ii) excess respiratory rate of >10 breaths per minute (adjusted OR = 1.51, 95% CI: 1.19, 1.92), (iii) vomiting at enrolment (adjusted OR = 1.49, 95% CI: 1.13, 1.96), (iv) history of use of broncho-dilators (adjusted OR = 1.71, 95% CI: 1.30, 2.24) and (v) non-adherence (adjusted OR = 8.06, 95% CI: 4.36, 14.92). Conclusions Treating children with non-severe pneumonia and wheeze with a placebo is not equivalent to treatment with oral amoxycillin. Trial Registration ClinicalTrials.gov NCT00407394

A Systematic Review of Hepatitis E Virus Infection in Children

A systematic review was conducted, seeking all literature relevant to the epidemiology, clinical and laboratory features, and outcome of hepatitis E virus (HEV) infection in children. Transmission is thought to be primarily from fecal-oral transmission, with the role of transmission from animal reservoirs not being clear in children. Worldwide, seroprevalence is <10% up to 10 years of age, with the exception of 1 of 5 studies from India and the sole study from Egypt. Seroprevalence increases with age, but it is not clear if it is increasing over time. The clinical presentation of HEV infection has broad similarities to hepatitis A virus (HAV) infection, with most cases being subclinical. However, HEV differs from HAV in that infectivity is lower, perinatal transmission can result in neonatal morbidity and even mortality, and a chronic carrier state exists, accounting for chronic hepatitis in some pediatric solid organ transplant recipients.

The frequency of HIV-I drug resistance mutations among treatment-naïve individuals at a tertiary care centre in south India

Antiretroviral treatment (ART) use in India requires information on baseline drug resistance mutations and polymorphisms in the protease (Pr) and reverse transcriptase (RT) genes of HIV-1 strains from treatment-naïve individuals. We report resistance predictor mutations and polymorphisms in the Pr and the RT sequence of non-clade B HIV-1 strains from ART naïve individuals. The genotypic resistance assay was done on 93 treatment-naïve individuals. The sequences were analysed by Stanford HIV drug resistance data for genotypic drug resistance analysis and REGA HIV-1 subtyping tool. Phylogenetic tree was generated with MEGA 4 for quality control. Ninety-two strains belonged to clade C and one to clade A (A1). Amino acid substitutions were seen at positions associated with drug resistance in Pr gene – 10, 24, 74 (each 3%) and position 82 (11%). Substitutions were seen at positions 41 (1%), 100 (1%), 101 (6%), 103 (2%), 179 (6%) and 181 (1%) of the RT sequence known to confer drug resistance in clade B. Polymorphisms in HIV-1 pol gene among treatment-naïve individuals were similar when compared with previous data. One strain each had Y181C substitution, T74S and E35G substitutions in the Pr and one had A98G, K101R and L210FL substitutions in RT.

Pneumococcal serotypes associated with invasive disease in under five children in India & implications for vaccine policy

Background & objectives: Streptococcus pneumoniae is a major cause of morbidity and mortality especially in children less than five years, particularly in India. We present data on S. pneumoniae infections in children less than five years age group, with response to its serotype distribution, antibiotic resistance profile and available vaccines expected coverage. Methods: Children aged less than five, who were suspected for invasive pneumococcal disease were included in the study and their sterile body fluids were investigated for the presence of S. pneumoniae. Invasive S. pneumoniae isolates from sterile body fluids were identified by bile solubility and optochin susceptibility test. Pneumococcal serotyping was performed with co-agglutination technique and reconfirmed with multiplex PCR. Results: The most common pneumococcal serotypes causing invasive infections in children less than five years of age were 14, 19F, 5, 6A and 6B. Of the 114 S. pneumoniae isolates studied, 110 (96.4%) were non-susceptible to co-trimoxazole and 30 per cent were non-susceptible to erythromycin, 5.2 per cent of the isolates were non-susceptible to penicillin and only 0.8 per cent was non-susceptible to cefotaxime. Interpretation & conclusions: Our results indicate that PCV-10 can protect against 64 per cent of serotypes causing invasive pneumococcal infections. Use of PCV-13 in this region can provide increase in protection upto 74.6 per cent against serotypes causing invasive pneumococcal infections. Incorporating PCV-13 in the Universal Immunization Programme may provide incremental protection against IPD serotypes in the southern region of the country.

Molecular detection and analysis of spotted fever group Rickettsia in patients with fever and rash at a tertiary care centre in Tamil Nadu, India

Abstract Background: Detection of specific targets by PCR is used to confirm a diagnosis of spotted fever, but serological tests are still widely used. In this prospective study, nested PCR was performed on skin biopsy specimens to confirm the diagnosis of spotted fever. Methods: In 58 clinically suspected cases of spotted fever, nested PCR, to detect gltA, 17 kDa lipoprotein antigen gene (17 kDa), ompA and ompB, from skin biopsy of the rash was performed. Sequencing was carried on amplicons representing the four targets to confirm specificity of amplification. This was followed by phylogenetic analysis using MEGA version 4.0 software. Results: The gltA, 17 kDa, ompA, and ompB genes were detected from skin biopsy specimens in 38, 23, 27, and 22 individuals. Sequence analysis revealed that the gltA, 17 kDa, ompA, and ompB sequences belonged to spotted fever group (SFG) rickettsia. Of the six partial ompA gene sequences, only one was dissimilar to the previously reported ‘Candidatus Rickettsia kellyi’. Conclusion: Further evidence indicates that SFG rickettsiae resembling ‘Candidatus Rickettsia kellyi’ cause fever and rash in southern India. More detailed phylogenetic analysis following isolation of rickettsia in culture is required for providing irrefutable proof for the occurrence of novel spotted fever rickettsiae in this region.

Drug resistant mutations detected by genotypic drug resistance testing in patients failing therapy in clade C HIV-1 infected individuals from India

PURPOSE There has been an increase in the number of individuals administered antiretroviral therapy (ART) in India but treatment outcome is hampered by increasing development of drug resistance. Previous reports from India have shown M184V as the commonest mutation in treated individuals. However, there is no evidence for any protease mutations in these reports. This study was done to observe the common/unique mutational patterns observed in reverse transcriptase (RT) and protease (Pr) genes of clade C HIV-1 strains from individuals showing treatment failure in India. MATERIALS AND METHODS The assay was done by sequencing the Pr and RT genes of the HIV-1 strains from 18 individuals failing ART. Analysis was carried out using Stanford HIV drug resistance database (SHDB). The sequences were also submitted to the calibrated population resistance tool of SHDB and Rega HIV-1 sub typing tool. Phylogenetic analysis and quality control were performed with Mega 4. RESULTS Among the 20 strains, 19 showed resistance to both nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), one strain to NNRTIs and five strains showed protease inhibitors (PI) resistance and 3-class resistance. The most common mutation conferring NRTI resistance was M184V (90%) while K103N (45%) was the most common mutation conferring NNRTI resistance. The M46I mutation was seen in 20% of the Pr sequences. CONCLUSION Resistance testing to check the prevalence of drug resistance mutations that arise following failure of the first line regimen to establish guidelines for second line regimens in India is a must. Studies are needed to confirm if mutation patterns that arise among clade C following failure of ART are the same as for clade B strains.

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in healthy infants and toddlers given with routine vaccines in India.

Background: The childhood burden of disease attributable to Streptococcus pneumoniae is particularly high in India. The immunogenicity and safety of 13-valent pneumococcal conjugate vaccine (PCV13) were compared with 7-valent pneumococcal conjugate vaccine (PCV7) in a randomized, active-controlled, double-blind trial conducted at 12 sites in India. Methods: Healthy infants received PCV13 or PCV7 at 6, 10, and 14 weeks of age (infant series) and at 12 months of age (toddler dose), along with routine pediatric vaccinations. Immunoglobulin G responses against the 13 pneumococcal serotypes were evaluated 1 month after the infant series and after the toddler dose. Pertussis and poliomyelitis immune responses were assessed 1 month after the infant series. Safety and tolerability also were assessed. Results: The immunogenicity results for the 7 common serotypes and the concomitant vaccines (whole-cell pertussis and oral poliovirus) were similar for subjects receiving PCV13 and subjects receiving PCV7. Immune responses to the 6 additional serotypes were higher in the PCV13 group compared with the PCV7 group. PCV13 and PCV7 had similar safety and tolerability profiles. Conclusions: PCV13 has immunogenicity similar to PCV7 in response to the 7 common serotypes, and has generally higher immunogenicity in response to the 6 additional serotypes. PCV13 may provide added protection against pneumococcal disease caused by the additional 6 serotypes and does not interfere with immune responses to whole-cell pertussis and oral poliovirus vaccines. PCV13 has an acceptable safety profile in both infants and toddlers, comparable with that of PCV7.

Immunogenicity, safety and reactogenicity of the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) when co-administered with the DTPw-HBV/Hib vaccine in Indian infants: a single-blind, randomized, controlled study

In India, pneumococcal diseases are major causes of child mortality, and effective vaccines against Streptococcus pneumoniae are needed. This single-blind, randomized study assessed the immunogenicity, reactogenicity, and safety of the 10-valent pneumococcal non-typeable Haemophilus influenzae (NTHi) protein D conjugate vaccine (PHiD-CV) co-administered with DTPw-HBV/Hib in Indian infants as 3-dose primary vaccination course. A total of 360 infants were randomized (2:1) to receive either PHiD-CV co-administered with DTPw-HBV/Hib (PHiD-CV group) or a Hib vaccine co-administered with DTPw-HBV (control group) at 6, 10, and 14 weeks of age. For each vaccine pneumococcal serotype, the percentage of infants in the PHiD-CV group with antibody concentrations ≥ 0.2 µg/mL one month after the third vaccine dose was at least 98.3%, except for serotypes 6B (77.7%) and 23F (89.5%), and opsonophagocytic activity titers ≥ 8 were measured in at least 95.7% of infants, except for serotypes 1 (90.5%) and 6B (84.5%). In addition, all the infants in the PHiD-CV group were seroprotected against diphtheria, tetanus, Hib, and hepatitis B or seropositive for antibodies against pertussis and NTHi protein D (except one infant). Incidences of solicited local and general symptoms were comparable between groups, except for fever (axillary temperature ≥ 37.5°C), which seemed to occur more frequently in the PHiD-CV group. In conclusion, PHiD-CV was shown to be immunogenic and well-tolerated when co-administered with DTPw-HBV/Hib in Indian infants. This study has been registered at www.clinicaltrials.gov NCT00814710.

Mechanisms of Carbapenem Resistance in K.pneumoniae and E. coli from Bloodstream Infections in India

Introduction: Emergence and global spread of carbapenemase producing Enterobacteriaceae (CPE) are of great concern in healthcare settings. Resistance to carbapenem is mostly conferred by metallo β-lactamase (IMP, VIM and NDM) and carbapenem hydrolyzing class D β-lactamase (OXA-48 like). The aim of this study was to characterise the molecular mechanism of resistance in the clinical isolates of Enterobacteriaceae causing bacteremia and showing resistance to β-lactams, including carbapenems. Materials and Methods: Isolates of E.coli (n=42) and K. pneumoniae (n=134) from blood culture collected during 2013-2015 were screened for carbapenemase production by using carba NP test and the presence of carbapenem resistant genes (KPC, IMP, VIM, NDM and OXA- 48 like). Sequencing was performed for the randomly selected isolates positive for NDM and OXA-48 like.Results: Of the 176 isolates, 97% of the isolates were found to be positive with carba NP test. Carba NP test has the sensitivity, specificity, PPV and NPV of 98%, 50%, 99% and 20% respectively. Each of blaNDM and blaOXA-48 like was seen in 32% of the tested isolates. Co-production of blaNDM and blaOXA48 like and blaVIM and blaOXA48 were seen in 13% and 8% of isolates respectively. Noticeably, 3% of isolates were identified as co-producers of blaNDM, blaVIM and blaOXA48 like. All of the sequenced NDM and OXA-48 like were identified as NDM-1 and OXA-181 variants. Conclusion: Increasing incidence of OXA-48 like is worrisome in developing countries. Because of its weak hydrolytic acivity against broad spectrum cephalosporin and carbapenems, these may go undetected in routine screening. In particular, blaOXA48 like gene is mostly identified on the plasmid and is implicated as the cause for silent spread and outbreaks in hospitalized patients.