Contextual Narratives Associated With Immunization Services During COVID-19 Disease Outbreak in Chennai, Tamil Nadu

Background: Essential health services including immunization were significantly impacted due to COVID-19 with devastating outcomes in low- and middle-income countries (LMIC). The disruption in immunization services due to global pandemic and measures undertaken at regional levels to overcome need to be studied as pandemic preparedness strategy. Objective: To document the contextual narratives related to immunization services during the Covid-19 disease outbreakby interviewing qualified paediatricians in the field practice area of private tertiary care teaching medical college Methodology: In-depth phone-based interviews were conducted with paediatricians in diverse settings during November 2020 to March 2021. Reflexive thematic analysis was performed, major themes identi-fied, and case studies documented. Results: Paediatricians shared rich experiences related to immunization services impacted due to COVID-19 especially during the earlier months due to imposition of lockdowns leading to discontinua-tion, disruption of services, decrease in volume of immunizations, modest transition to telehealth ser-vice delivery, facility-level changes brought in to ensure immunization services and capacity building measures for upskilling. Conclusions: Contextual narratives revealed in this study provide rich narrative about the disruption of immunization services due to COVID-19. These findings need to be understood and leveraged to be fu-ture ready and prevent further disruptions by identifying and scaling up key solutions piloted in this study.

Tobacco Harm Reduction Approach in Clinical Practice: A Qualitative Study among Multi-Specialty Healthcare Professionals in an Indian Metropolitan City

Background:Tobacco harm reduction when advocated by care providers as continuum of care towards the goal of tobacco cessation might result in long-term abstinence than it is currently seen. This study aimed to qualitatively explore the healthcare professionals approach and self-reported practices related to tobacco harm reduction and smoking cessation. Methods: A purposive sample (N=36) of multi-specialty healthcare professionals providing tobacco related cessation services at six private medical teaching institutes were engaged in semi-structured qualitative interviews between July 2020 and October 2020 in Chennai. Results: The results indicated that majority of the healthcare professional抯 lack conceptual understanding about tobacco harm reduction. Harm reduction was practised and nicotine replacement therapy was prescribed by psychiatrists in this study. Majority of the healthcare professionals were found to have misconceptions that promoting harm reducing practices instead of cessation might result in continued addiction to nicotine products among the clientele. Conclusions: The findings reveal that tobacco harm reduction remains an under-utilized clinical practise in Indian setting due to knowledge and awareness gaps among multi-specialty healthcare professionals. Improved sensitization through continuous medical education updates is needed to inform effective clinician-affirmative tobacco harm reduction practices.

Pneumococcal vaccines

Streptococcus pneumoniae continues to take a heavy toll on childhood mortality and morbidity across the developing world. An estimated 10.6 million invasive pneumococcal diseases (IPDs) occur every year, with nearly 1 million deaths in children under 5 years of age. Introduction of vaccines in the childhood immunisation programme in developed world has brought down the incidence of the disease considerably. However, childhood immunocompromising illnesses including HIV have increased the risk of IPD several folds. There is also a growing concern on the increasing antibiotic resistance among these invasive strains to penicillin, other beta-lactams and macrolides, making treatment difficult and expensive. It is estimated that about 62% of IPD worldwide is caused by the 10 most common serotypes. Although the ranking of individual pneumococcal serotypes causing serious disease varies among nations, the 7� serotypes included in pneumococcal conjugate vaccines (PCVs) may prevent 50%�% of all paediatric pneumococcal diseases globally. The World Health Organization has recommended the use of PCV-10/13 in the national immunisation programmes (NIPs) of developing countries. Four doses of PCV-13 have been recommended by the US Association of Pediatrics and Centers for Disease Control and Prevention, at intervals of each 2 months for the first 6 months and by the 12th to 15th months after birth. This is expected to reduce the morbidity and mortality associated with IPD and simultaneously decrease colonisation with circulating antibiotic-resistant strains in immunized communities. Nevertheless, continued surveillance of antimicrobial resistance in non-vaccine serotypes is necessary to prevent the resurgence of resistance. Other virulence factors which are not serotype specific also need to be studied to overcome the drawbacks of serotype-specific pneumococcal vaccines. PCV-13 was launched during May 2017 under the NIP of five Indian states with the highest pneumococcal diseases in the country and is expected to be rolled out in the other parts of the country in the coming days.

Multidrug resistance mediated by co‑carriage of extended‑spectrum beta‑lactamases, AmpC and New Delhi metallo‑beta‑lactamase‑1 genes among carbapenem‑resistant Enterobacteriaceae at five Indian medical centres.

In this study, we evaluated the coexistence of extended‑spectrum beta‑lactamases (ESBL), AmpC and New Delhi metallo‑beta‑lactamase‑1 (NDM‑1) genes among carbapenem‑resistant Enterobacteriaceae (CRE) recovered prospectively from patients at multiple sites. The study included 285 CRE strains from 2782 Gram‑negative Bacilli collected from multiple centres during 2007–2010, of which 87 were characterised. Standard and reference laboratory methods were used for resistance determination. Detection of blaNDM‑1, blaAmpC, blaTEM, blaSHV and blaCTX‑M was done by polymerase chain reaction. High levels of antimicrobial resistance observed among study isolates. Co‑carriage of ESBLs, AmpC and NDM‑1 was 26.3%. Nosocomial origin among the co‑carriage isolates was 64.3%, with 9.2% associated mortality.

Assessing effect of climate on the incidence of dengue in Tamil Nadu.

Incidence of dengue is reported to be influenced by climatic factors. The objective of this study is to assess the association of local climate with dengue incidence, in two geographically distinct districts in Tamil Nadu. The study uses climate data, rainfall and mean maximum and minimum temperature to assess its association if any, with dengue incidence in two districts of Tamil Nadu, South India. According to this study while precipitation levels have an effect on dengue incidence in Tamil Nadu, non-climatic factors such as presence of breeding sites, vector control and surveillance are important issues that need to be addressed.

Detection of metallo-β-lactamases producing Acinetobacter baumannii using microbiological assay, disc synergy test and PCR.

Background: One leading factor responsible for resistance in Acinetobacter baumannii, an important opportunist in health care institutions globally, is the production of carbapenamases like metallo-β-lactamases (MBLs), which hydrolyze a variety of β-lactams including penicillin, cephalosporins and carbapenems. However, neither any standard guidelines are available nor any method has been found to be perfect for their detection. Various methods have shown discordant results, depending upon the employed methodology, β-lactamase substrate and MBL inhibitor used. This study aims to evaluate two phenotypic methods against PCR as gold standard among carbapenem resistant A. baumannii for identifying MBL producers. Materials and Methods: A total of 130 A. baumannii were screened for imipenem and meropenem resistance by Kirby-Bauer disc diffusion method. Phenotypic expression of MBL was detected by EDTA-imipenem-microbiological (EIM) assay and extended EDTA disc synergy (eEDS) test and presence of bla-IMP and bla-VIM was detected by PCR in all the carbapenem resistant isolates. Results: Of the 43 imipenem and/or meropenem resistant A. baumannii isolates, 4 (9.3%) were found to be MBL producers by EIM and 3 (6.97%) by eEDS. Only bla-VIM gene was detected in 7 (16.28%) by PCR. In addition EIM detected 14 (32.56%) carbapenem resistant non-metallo enzyme producers. Conclusion: Of the two MBL genes targeted, bla-VIM was only detected and that too in isolates resistant to both imipenem and meropenem. Further, EIM was useful in differentiating MBL from non-metalloenzymes producers.

Detection and characterization of metallo beta lactamases producing Pseudomonas aeruginosa.

This study was undertaken to evaluate phenotypic and genotypic methods for detection of Metallo-Beta-Lactamases (MBLs) among nosocomial Pseudomonas aeruginosa. Sixty one among 176 P. aeruginosa isolates, collected as part of a multicentric study (2005-2007), were evaluated for carbapenem resistance (CARB-R; resistant to either imipenem/meropenem) and screened for MBL by Combination Disk Diffusion Test (CDDT) using imipenem (IMP), meropenem (MER) and ceftazidime (CAZ) with EDTA. MBL positives were further confirmed by IMP + EDTA Etest. Twenty strains (42.6%) were found to be MBL producers among the 61 P. aeruginosa. PCR for IMP and VIM MBL was performed on 48 of the 61, 15 were positive for VIM MBL type. CDDT using IMP + EDTA had the highest sensitivity and specificity of 87.8% and 84.4% when compared to Etest, which was higher than the values obtained for CAZ + EDTA and MER + EDTA. CDDT using IMP + EDTA also compared very well with the PCR (specificity = 90.9%, sensitivity = 93.3%). CARB-R among P. aeruginosa is mediated predominantly via MBL production. Clinical P. aeruginosa isolates can be screened routinely using the less expensive IMP + EDTA CDDT in clinical microbiology laboratories.

Rapid assay for detection of chloramphenicol acetyl transferase in Haemophilus influenzae.

BACKGROUND & OBJECTIVES: Haemophilus influenzae causes a variety of life threatening infections in humans. Early detection of antimicrobial resistance is of importance in the treatment and management of infection. The modified Slack's method, a simple assay, has been evaluated in this study for the early detection of chloramphenicol resistance. METHODS: Fifty isolates of H. influenzae from invasive and non-invasive sites were included. Antimicrobial susceptibility testing was done by disc diffusion method and minimum inhibitory concentration (MIC) determination was performed for chloramphenicol only. Modified Slack's method was used to test for the production of chloramphenicol acetyl transferase (CAT). RESULTS: Invasive isolates showed higher degree of resistance to chloramphenicol (72%) compared to non-invasive ones (28%). One hundred per cent association was found between results of disc diffusion, MIC and CAT production amongst strains resistant to chloramphenicol. INTERPRETATION & CONCLUSION: The findings suggested that chloramphenicol still remains the drug of choice for treatment for non-invasive infection caused by H. influenzae. Modified Slack's method is a simple, rapid, inexpensive and reliable method for the detection of chloramphenicol resistance amongst H. influenzae.

Systemic bacterial infections in bone marrow transplant patients.

The clinical microbiology department at CMC&H, Vellore in conjunction with the haematology department carries out routine surveillance of patients admitted to the hematology department. Since 1994 in a sample population of 55 patients with various underlying clinical conditions who have had bone marrow transplant, sepsis was observed in 16 patients (29%). The predominant Gram negatives associated with sepsis were non-fermenting Gram negative bacilli and all the 5 Gram positives were coagulase negative staphylococci. These organisms were susceptible to most of the routinely used antimicrobial agents. Continued surveillance is needed to determine changing trends with respect to organisms causing systemic infections and their susceptibility to antimicrobials.

Changing trend in susceptibility pattern of Streptococcus pneumoniae to penicillin in India.

Prior to 1995 all strains of Streptococcus pneumoniae isolated at a tertiary care hospital in south India were uniformly susceptible to penicillin. However, since late 1995 strains of S. pneumoniae with intermediate resistance to penicillin have been observed. Altogether there were 25 such isolates, 9 from invasive (5 from CSF as well as blood, 1 from pleural fluid and 3 from CSF alone) and 16 from noninvasive sites (6 from throat, 6 from sputum, 3 from eye and 1 from ear) respectively, thus 4.6 per cent of S. pneumoniae showed intermediate resistance of a total of 535 strains studied so far. The minimum inhibitory concentration (MIC) values of penicillin, erythromycin, chloramphenicol and cefotaxime were determined by agar dilution method and for confirmation, E test was carried out for penicillin alone. The MIC range obtained for penicillin was between 0.125-1.0 microgram/ml. Kirby-Bauer disc diffusion method was adopted for testing of erythromycin, chloramphenicol, co-trimoxazole, cefotaxime, tetracycline and vancomycin. We observed that none of the strains with intermediate resistance to penicillin were multidrug resistant. These strains belonged predominantly to serotype 14 (n = 10), 7B (n = 9), 19A (n = 3), 7F (n = 2) and 23F (n = 1). Clonality was not observed in the 5 representative strains subjected to Box A finger printing method.

Trend of Wuchereria bancrofti infection in Pondicherry urban agglomeration after the withdrawal of a five year vector control programme.

A study was undertaken to investigate the changes in the prevalence of bancroftian filariasis after six years of withdrawal of a five year (1981-85) vector control programme in Pondicherry and the results are presented in this paper. Though there was a drastic increase in the intensity of transmission of filariasis after the withdrawal of vector control operations in 1986, the prevalence of microfilaria (mf rate) of the population declined from 6.35% in 1986 to 4.80% in 1992 (P < 0.05). However, there was an appreciable increase in the mf rate and intensity in the children (0.5 year) born after the withdrawal of the control operations. The overall loss rate of infection was much higher than the gain rate. Many people found to be microfilaraemic six years before, became amicrofilaraemic now. The overall reduction in mf rate, higher loss rate of infection and microfilaraemic people turning amicrofilaraemic indicate that chemotherapy, which has been intensified during the last five years under the National Filaria Control Programme (NFCP), was playing a major role in reducing the infection. However, implementation of mass chemotherapy with annual single dose of DEC (6 mg/kg), combined with vector control may yield better results in further reducing the mf rate as the current approach of detection for treatment may become increasingly difficult with gradual fall in endemicity level. Mass chemotherapy will provide an opportunity to further reduce the mf rate and eliminate filariasis within a few years from Pondicherry urban agglomeration. The increase in the incidence of infection in children, born after the withdrawal of the vector control programme clearly indicates that transmission is continuing and if immediate action is not undertaken it would be difficult to sustain the gains.

In vitro activity of netilmicin against clinical isolates of methicillin resistant and susceptible Staphylococcus aureus.

BACKGROUND: The emergence of methicillin-resistant Staphylococcus aureus and its multidrug-resistant property has led to the search for an effective antibiotic to combat staphylococcal sepsis. At present, vancomycin remains the most effective antibiotic. This study evaluated the in vitro efficacy of netilmicin (an aminoglycoside) and compared its activity with 4 other antibiotics, viz. vancomycin, amikacin, tobramycin and ofloxacin. METHODS: The minimum inhibitory concentration of the antibiotics was determined by the agar dilution method. Thirty strains each of methicillin-resistant and -susceptible S. aureus isolated from pus and blood cultures were included. RESULTS: The susceptibility to netilmicin was found to be 100% and was the same as that observed for vancomycin. CONCLUSION: All the methicillin-resistant S. aureus strains tested showed 100% susceptibility to netilmicin, suggesting its use in patients with such infections as an alternative to vancomycin. However, this finding needs to be verified in the clinical setting.

Utility of catalytic models in the estimation of incidence and prevalence of malaria in a hyperendemic situation.

Simple catalytic models were used for estimating the true incidence of malaria in hyperendemic villages of Koraput District in Orissa State where Plasmodium falciparum is predominant. The hill top villages recorded a slide positive rate of 45.68. The daily rate of inoculation among infants was estimated to be 0.00781. The inoculation rate was so high that the recovery from one infection was compensated by the subsequent infection and hence the prevalence continued to increase with age. The model adequately represents the observed data for infants but could not be used for estimating the true prevalence in the adult population without incorporating other factors like immunity and superinfection.

Spatial and temporal variations in prevalence, intensity and aggregation of microfilaria in the human host.

The prevalence, intensity and the frequency distribution of microfilaria (mf) of Wuchereria bancrofti in the human blood and their variation in time (pre-vector control, control and post control periods) and space have been examined. The prevalence and intensity showed significant variation between time and different areas of urban Pondicherry. The significant reduction in the prevalence and intensity of microfilaremia in the areas of high endemicity indicated that the effect of vector control was well marked in these areas. The distribution of microfilaria in human population was adequately described by the truncated negative binomial prior to interruption of transmission, and the dispersion parameter 'k' of the negative binomial varied between 0.17 and 0.68. A change in the distribution was observed after the 5 years of vector control, during which the transmission was completely interrupted. The increased 'k' values suggest that the distribution of mf is influenced by the degree of exposure to infection. Therefore, comparison of changes in the parameter 'k' can be considered as an additional tool for evaluating the control operations aimed at interrupting the transmission.

Microlevel epidemiological variations in malaria & its implications on control strategy.

Microlevel epidemiological variations in designing malaria control strategies were studied. Quantitative and qualitative variations were observed between two physiographic zones and between four different ecotypes within the zones of the Koraput district. While the peak transmission occurred in rainy season in the 600 m plateau (Jeypore zone), the same was observed in cold season in 150 m plateau (Malkangiri zone). The age specific parasite prevalence indicated a high degree of transmission and high level of acquired immunity in top- and foot-hill villages of both zones as compared to plain and riverine villages. Transmission was perennial in top-hill and foot-hill villages while it was of short period (indicated by infant parasite rate) in others. Since the period and intensity of transmission vary, an uniform residual insecticidal spray schedule as followed at present is not necessary. Majority of fever patients in top-hill villages were positive for Plasmodium falciparum and therefore may be treated for malaria without slide collection and examination. Evaluations may be done by sample surveys. These steps can optimize the malaria control operation in the district.