Exploring ex vivo biofilm dynamics: consequences of low ampicillin concentrations on the human oral microbiome.

Prolonged exposure to antibiotics at low concentration can promote processes associated with bacterial biofilm formation, virulence and antibiotic resistance. This can be of high relevance in microbial communities like the oral microbiome, where commensals and pathogens share a common habitat and where the total abundance of antibiotic resistance genes surpasses the abundance in the gut. Here, we used an ex vivo model of human oral biofilms to investigate the impact of ampicillin on biofilm viability. The ecological impact on the microbiome and resistome was investigated using shotgun metagenomics. The results showed that low concentrations promoted significant shifts in microbial taxonomic profile and could enhance biofilm viability by up to 1 to 2-log. For the resistome, low concentrations had no significant impact on antibiotic resistance gene (ARG) diversity, while ARG abundance decreased by up to 84%. A positive correlation was observed between reduced microbial diversity and reduced ARG abundance. The WHO priority pathogens Streptococcus pneumoniae and Staphylococcus aureus were identified in some of the samples, but their abundance was not significantly altered by ampicillin. Most of the antibiotic resistance genes that increased in abundance in the ampicillin group were associated with streptococci, including Streptococcus mitis, a well-known potential donor of ARGs to S. pneumoniae. Overall, the results highlight the potential of using the model to further our understanding of ecological and evolutionary forces driving antimicrobial resistance in oral microbiomes.

An algorithmic approach to identifying the aetiology of acute encephalitis syndrome in India: results of a 4-year enhanced surveillance study.

BACKGROUND: Annual outbreaks of acute encephalitis syndrome pose a major health burden in India. Although Japanese encephalitis virus (JEV) accounts for around 15% of reported cases, the aetiology of most cases remains unknown. We aimed to establish an enhanced surveillance network and to use a standardised diagnostic algorithm to conduct a systematic evaluation of acute encephalitis syndrome in India. METHODS: In this large-scale, systematic surveillance study in India, patients presenting with acute encephalitis syndrome (ie, acute onset of fever with altered mental status, seizure, or both) to any of the 18 participating hospitals across Uttar Pradesh, West Bengal, and Assam were evaluated for JEV (serum and cerebrospinal fluid [CSF] IgM ELISA) per standard of care. In enhanced surveillance, JEV IgM-negative specimens were additionally evaluated for scrub typhus, dengue virus, and West Nile virus by serum IgM ELISA, and for Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, dengue virus, herpes simplex virus, and enterovirus by CSF PCR across five referral laboratories. In 2017, chikungunya and Leptospira serum IgM by ELISA and Zika virus serum and CSF by PCR were also tested. FINDINGS: Of 10 107 patients with acute encephalitis syndrome enrolled in enhanced surveillance between Jan 1, 2014, and Dec 31, 2017, 5734 (57·8%) of 9917 participants with available data were male and 6179 (62·7%) of 9856 were children aged 15 years and younger. Among patients who provided a sample of either CSF or serum in enhanced surveillance, an aetiology was identified in 1921 (33·2%) of 5786 patients enrolled between 2014 and 2016 and in 1484 (34·3%) of 4321 patients enrolled in 2017. The most commonly identified aetiologies were JEV (1023 [17·7%] of 5786 patients), scrub typhus (645 [18·5%] of 3489), and dengue virus (161 [5·2%] of 3124). Among participants who provided both CSF and serum specimens, an aetiology was identified in 1446 (38·3%) of 3774 patients enrolled between 2014 and 2016 and in 936 (40·3%) of 2324 enrolled in 2017, representing a 3·1-times increase in the number of patients with acute encephalitis syndrome with an identified aetiology compared with standard care alone (299 [12·9%]; p<0·0001). INTERPRETATION: Implementation of a systematic diagnostic algorithm in an enhanced surveillance platform resulted in a 3·1-times increase in identification of the aetiology of acute encephalitis syndrome, besides JEV alone, and highlighted the importance of scrub typhus and dengue virus as important infectious aetiologies in India. These findings have prompted revision of the national testing guidelines for this syndrome across India. FUNDING: US Centers for Disease Control and Prevention.

India's need for long-term solutions to COVID-19-like pandemics: A policy paper by Organized Medicine Academic Guild.

The entire world seems to have responded to COVID-19 pandemic in a knee-jerk manner with a short mindset without building on the existing strengths of public health infrastructure. National governments cannot be blamed for this as we are dealing with a crisis that comes once in a lifetime. Realising this, the Organized Medicine Academic Guild (OMAG) an association of major health associations in this country has suggested measures for long-term solutions to COVID-19-like pandemics in the form of a policy paper by OMAG.

The Barts Health NHS Trust COVID-19 cohort: characteristics, outcomes and risk scoring of patients in East London.

BACKGROUND: Barts Health National Health Service Trust (BHNHST) serves a diverse population of 2.5 million people in London, UK. We undertook a health services assessment of factors used to evaluate the risk of severe acute respiratory coronavirus 2 (SARS-CoV-2) infection.METHODS: Patients with confirmed polymerase chain reaction (PCR) test results admitted between 1 March and 1 August 2020 were included, alongwith clinician-diagnosed suspected cases. Prognostic factors from the 4C Mortality score and 4C Deterioration scores were extracted from electronic health records and logistic regression was used to quantify the strength of association with 28-day mortality and clinical deterioration using national death registry linkage.RESULTS: Of 2783 patients, 1621 had a confirmed diagnosis, of whom 61% were male and 54% were from Black and Minority Ethnic groups; 26% died within 28 days of admission. Mortality was strongly associated with older age. The 4C mortality score had good stratification of risk with a calibration slope of 1.14 (95% CI 1.01-1.27). It may have under-estimated mortality risk in those with a high respiratory rate or requiring oxygen.CONCLUSION: Patients in this diverse patient cohort had similar mortality associated with prognostic factors to the 4C score derivation sample, but survival might be poorer in those with respiratory failure.

Comparative genetic variability in HIV-1 subtype C p24 Gene in early age groups of infants.

It is important to study the molecular properties of vertically transmitted viruses in early infancy to understand disease progression. P24 having an important role in virus assembly and maturation was selected to explore the genotypic characteristics. Blood samples, obtained from 82 HIV-1 positive infants, were categorized into acute (≤ 6 months) and early (> 6-18 months) age groups. Of the 82 samples, 79 gave amplification results for p24, which were then sequenced and analysed. Amino acid heterogeneity analysis showed that substitutions were more frequent. Several substitution mutations were present in some of the sequences of both the age groups in the functional motifs of the gene namely Beta hairpin, CyPA binding loop, residues L136 and L190, linker region and major homology region. In the acute age group, an insertion of Asparagine residue (N5NL6) was observed in the ß hairpin region in one of the sequences. This insertion was accompanied with analogous substitutions of N5Q, Q7L and G8R. In the early age group, a deletion of two residues; VK181-182, was observed at the C-terminal end in one of the sequences. These mutations may impair the structure of the protein leading to defective virus assembly. Protein variation effect analyzer software showed that deleterious mutations were more in the acute than the early age group. Variability analysis revealed that the amino acid heterogeneity was comparatively higher in the acute than the early age group. Variability in the virus was decreasing with the increasing age of the infants indicating that the virus is gradually evolving under positive selection pressure. HLA class 1 binding peptide analysis showed that the epitopes TPQDLNTML and RMYSPVSIL may be helpful in designing epitope based vaccine.

Persistent diarrhoea in a 5-month-old baby carrying Vibrio cholerae nonO1/nonO139 producing Haitian cholera toxin.

Cholera toxin (CT) is the principal virulence factor of Vibrio cholerae for fatal cholera diarrhoea. Serogroups O1 and O139 harbour CT and are known to be epidemic strains. The remaining serogroups (nonO1/nonO139) are non-toxigenic and may be associated with mild disease. O1 serogroup emerged with a variant of CT known as Haitian cholera toxin (HCT). The HCT strains are hypervirulent and have been associated with severe cholera outbreaks in India, Western Africa and Haiti. Here, we report the presence of HCT (ctxB7) in a nonO1/nonO139 isolate causing persistent diarrhoea.

Adaptation of a malaria surveillance system for use in a visceral leishmaniasis elimination programme.

Background: Successful public practice relies on generation and use of high-quality data. A data surveillance system (the Disease Data Management System [DDMS]) in use for malaria was adapted for use in the Indian visceral leishmaniasis elimination programme. Methods: A situational analysis identified the data flows in current use. Taxonomic trees for the vector of visceral leishmaniasis in India, Phlebotomus argentipes, were incorporated into the DDMS to allow entry of quality assurance and insecticide susceptibility data. A new quality assurance module was created to collate the concentration of DDT that was applied to walls during the indoor residual spraying (IRS) vector control programme. Results: The DDMS was implemented in Bihar State and used to collate and manage data from sentinel sites in eight districts. Quality assurance data showed that DDT was under-applied to walls during IRS; this, combined with insecticide susceptibility data showing widespread vector resistance to DDT prompted a national policy change to using compression pumps and alpha-cypermethrin insecticide for IRS. Conclusions: The adapted DDMS centralises programmatic data and enhances evidence-based decision making and active policy change. Moving forward, further modules of the system will be implemented, allowing extended data capture and streamlined transmission of key information to decision makers.

Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study.

BACKGROUND: Outbreaks of unexplained illness frequently remain under-investigated. In India, outbreaks of an acute neurological illness with high mortality among children occur annually in Muzaffarpur, the country's largest litchi cultivation region. In 2014, we aimed to investigate the cause and risk factors for this illness. METHODS: In this hospital-based surveillance and nested age-matched case-control study, we did laboratory investigations to assess potential infectious and non-infectious causes of this acute neurological illness. Cases were children aged 15 years or younger who were admitted to two hospitals in Muzaffarpur with new-onset seizures or altered sensorium. Age-matched controls were residents of Muzaffarpur who were admitted to the same two hospitals for a non-neurologic illness within seven days of the date of admission of the case. Clinical specimens (blood, cerebrospinal fluid, and urine) and environmental specimens (litchis) were tested for evidence of infectious pathogens, pesticides, toxic metals, and other non-infectious causes, including presence of hypoglycin A or methylenecyclopropylglycine (MCPG), naturally-occurring fruit-based toxins that cause hypoglycaemia and metabolic derangement. Matched and unmatched (controlling for age) bivariate analyses were done and risk factors for illness were expressed as matched odds ratios and odds ratios (unmatched analyses). FINDINGS: Between May 26, and July 17, 2014, 390 patients meeting the case definition were admitted to the two referral hospitals in Muzaffarpur, of whom 122 (31%) died. On admission, 204 (62%) of 327 had blood glucose concentration of 70 mg/dL or less. 104 cases were compared with 104 age-matched hospital controls. Litchi consumption (matched odds ratio [mOR] 9·6 [95% CI 3·6 - 24]) and absence of an evening meal (2·2 [1·2-4·3]) in the 24 h preceding illness onset were associated with illness. The absence of an evening meal significantly modified the effect of eating litchis on illness (odds ratio [OR] 7·8 [95% CI 3·3-18·8], without evening meal; OR 3·6 [1·1-11·1] with an evening meal). Tests for infectious agents and pesticides were negative. Metabolites of hypoglycin A, MCPG, or both were detected in 48 [66%] of 73 urine specimens from case-patients and none from 15 controls; 72 (90%) of 80 case-patient specimens had abnormal plasma acylcarnitine profiles, consistent with severe disruption of fatty acid metabolism. In 36 litchi arils tested from Muzaffarpur, hypoglycin A concentrations ranged from 12·4 µg/g to 152·0 µg/g and MCPG ranged from 44·9 µg/g to 220·0 µg/g. INTERPRETATION: Our investigation suggests an outbreak of acute encephalopathy in Muzaffarpur associated with both hypoglycin A and MCPG toxicity. To prevent illness and reduce mortality in the region, we recommended minimising litchi consumption, ensuring receipt of an evening meal and implementing rapid glucose correction for suspected illness. A comprehensive investigative approach in Muzaffarpur led to timely public health recommendations, underscoring the importance of using systematic methods in other unexplained illness outbreaks. FUNDING: US Centers for Disease Control and Prevention.

Pharmacovigilance of Miltefosine in Treatment of Visceral Leishmaniasis in Endemic Areas of Bihar, India.

Miltefosine, the only oral drug for visceral leishmaniasis (VL), is being used as the first-line drug under the VL elimination program in the Indian subcontinent. Miltefosine is an oral drug which was used as a topical application for skin metastasis of breast cancer. It was found to be effective against Leishmania donovani The main adverse events (AE) reported previously with miltefosine use includes diarrhea, vomiting, and dehydration. Other AEs include, raised serum alanine transaminase/aspartate aminotransferase and renal parameters such as creatinine. In this study, we report AEs in a large patient cohort of VL treated with miltefosine. The purpose of this pharmacovigilance study was to assess adverse drug reactions (ADRs)/AE of miltefosine treatment under unrestricted condition in the field setup. Patients were followed up to 6 months for therapeutic effectiveness. Outcomes of a larger data set of patients treated with this regimen from April 2012 to March 2015 were recorded. In the present study, 646 patients of VL were given miltefosine. Majority of the study subjects (58%) were male. Relapse occurred in 7% during follow-up period. Main causes of death were VL-pulmonary tuberculosis coinfection, extreme diarrhea, and acute pancreatitis which were reported in 1.7% subjects. Of 553 (85.6%) patients completing full course of treatment, 463 (83.7%) showed ADR with miltefosine during the study period. About 2.3% were suffering severe ADR, 51% from moderate, and the rest had mild ADR. The initial and final cure rate was 97.4% and 85.6%, respectively.

Malaria situation in India with special reference to tribal areas.

BACKGROUND & OBJECTIVES: In India, malaria is a major public health problem in States having predominantly tribal population. The objective of this analysis was to find out the incidence of malaria in various States/districts having varied proportions of tribal population using National Vector Borne Disease Control Programme (NVBDCP) data. METHODS: States and districts were classified into three categories based on proportions of Scheduled Tribes (ST) population as <10, 10-29.9 and 30 per cent + ST population. Five year average (2008-2012) of all important malaria indicators collected by NVBDCP was taken to normalize the effect of annual fluctuations in malaria incidence. RESULTS: State level analysis revealed that ten States/UTs with 30 per cent or more tribal population comprising only three per cent of total population, contributed 14 per cent of total malaria, 21 per cent Plasmodium falciparum and 29 per cent of deaths due to malaria. Similarly, district level analysis showed that districts with 30 per cent or more tribal population comprising about eight per cent country's population contributed to 46 per cent of total malaria cases, 70 per cent P. falciparum and 47 per cent malarial deaths in the country. INTERPRETATION & CONCLUSIONS: Our analysis showed that the neglect of the ethnic communities in tribal areas would be detrimental to the overall reduction of morbidity and mortality due to malaria. The fight against the increasing burden of malaria in tribal belt requires adoption of multiple approaches and socio-economic development of the tribal communities.

Sildenafil in pediatric pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a life-threatening disease of varied etiologies. Although PAH has no curative treatment, a greater understanding of pathophysiology, technological advances resulting in early diagnosis, and the availability of several newer drugs have improved the outlook for patients with PAH. Sildenafil is one of the therapeutic agents used extensively in the treatment of PAH in children, as an off-label drug. In 2012, the United States Food and Drug Administration (USFDA) issued a warning regarding the of use high-dose sildenafil in children with PAH. This has led to a peculiar situation where there is a paucity of approved therapies for the management of PAH in children and the use of the most extensively used drug being discouraged by the regulator. This article provides a review of the use of sildenafil in the treatment of PAH in children.

Outbreaks of unexplained neurologic illness - Muzaffarpur, India, 2013-2014.

Outbreaks of an unexplained acute neurologic illness affecting young children and associated with high case-fatality rates have been reported in the Muzaffarpur district of Bihar state in India since 1995. The outbreaks generally peak in June and decline weeks later with the onset of monsoon rains. There have been multiple epidemiologic and laboratory investigations of this syndrome, leading to a wide spectrum of proposed causes for the illness, including infectious encephalitis and exposure to pesticides. An association between illness and litchi fruit has been postulated because Muzaffarpur is a litchi fruit-producing region. To better characterize clinical and epidemiologic features of the illness that might suggest its cause and how it can be prevented, the Indian National Centre for Disease Control (NCDC) and CDC investigated outbreaks in 2013 and 2014. Clinical and laboratory findings in 2013 suggested a noninflammatory encephalopathy, possibly caused by a toxin. A common laboratory finding was low blood glucose (<70 mg/dL) on admission, a finding associated with a poorer outcome; 44% of all cases were fatal. An ongoing 2014 investigation has found no evidence of any infectious etiology and supports the possibility that exposure to a toxin might be the cause. The outbreak period coincides with the month-long litchi harvesting season in Muzaffarpur. Although a specific etiology has not yet been determined, the 2014 investigation has identified the illness as a hypoglycemic encephalopathy and confirmed the importance of ongoing laboratory evaluation of environmental toxins to identify a potential causative agent, including markers for methylenecyclopropylglycine (MCPG), a compound found in litchi seeds known to cause hypoglycemia in animal studies. Current public health recommendations are focused on reducing mortality by urging affected families to seek prompt medical care, and ensuring rapid assessment and correction of hypoglycemia in ill children.

Colistin: re-emergence of the 'forgotten' antimicrobial agent.

The treatment of the emerging multidrug resistant (MDR) gram-negative organisms is a challenge. The development of newer antibiotics has recently slowed down. This has led to the re-emergence of the 'old forgotten' antibiotic "Colistin", whose use had almost stopped (after 1970's) due to the high incidence of nephrotoxicity and neurotoxicity. Colistin (polymyxin E) is a polypeptide antibiotic belonging to polymyxin group of antibiotics with activity mainly against the gram-negative organisms. Use of colistin has been increasing in the recent past and newer studies have shown lesser toxicity and good efficacy. Colistin acts on the bacterial cell membrane resulting in increased cell permeability and cell lysis. Colistin can be administered orally, topically, by inhalational route, intramuscularly, intrathecally, and also intravenously. Parenteral Colistin (in the form of colistimethate sodium) has been used to treat ventilator-associated pneumonia (VAP) and bacteremia caused by MDR bacteria such as Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Inhaled Colistin is used for treating pneumonia/VAP due to MDR gram-negative organisms and also used prophylactically in patients with cystic fibrosis. This manuscript is a brief review of Colistin and its clinical applications in the pediatric population.

Monitoring antimalarial drug resistance in India via sentinel sites: outcomes and risk factors for treatment failure, 2009-2010.

OBJECTIVE: To describe India's National Antimalarial Drug Resistance Monitoring System, measure the efficacy of first-line malaria treatments, and determine risk factors for treatment failure. METHODS: In 2009-2010, prospective studies with 28 days of follow-up were conducted at 25 sentinel sites. Patients infected with Plasmodium falciparum were given artesunate plus sulfadoxine-pyrimethamine (AS+SP); those infected with P. vivax were given chloroquine. Polymerase chain reaction was used to distinguish post-treatment reinfection from treatment failure. Isolates of P. falciparum were checked for dhfr and dhps mutations. FINDINGS: Overall, 1664 patients were enrolled. Kaplan-Meier survival analysis showed an efficacy of 98.8% for AS+SP. Most patients with P. falciparum parasitaemia cleared their parasitaemias within 24 hours of treatment initiation, but six, including four with treatment failure, remained parasitaemic after 72 hours. Double mutants in dhfr were found in 68.4% of the genotyped isolates. Triple or quadruple mutants in dhfr and mutations in dhps were rare. A daily dose of artesunate of < 3 mg per kg of body weight, age of less than 5 years, and fever at enrolment were associated with an increased risk of treatment failure. Chloroquine remained 100% efficacious and generally cleared P. vivax parasitaemias within 48 hours. Vomiting (seen in 47 patients) was the most common adverse event. CONCLUSION: India's National Antimalarial Drug Resistance Monitoring System provides wide coverage. The first-line antimalarials used in the country remain safe and efficacious. The treatment of malaria in young children and the relative benefits of age- and weight-based dosing need further exploration.

Impact of mass drug administration on elimination of lymphatic filariasis in Surat city, India.

Lymphatic filariasis (LF) is one of the major public health problems in some of the endemic districts in India including Surat city of Gujarat province. Historical data reveals that in 1960s, Surat city had infection rate of about 23% and infectivity rate of 1.6%. Since then, Surat city has been reporting the cases of Lymphoedema and hydrocele. Filaria Control Unit was established under National Filaria Control Programme to detect and provide treatment to the cases. Based on the reports of NFCP, Surat City has been considered as LF endemic. During 2004, the country launched campaign of Elimination of Lymphatic Filariasis through Mass Drug Administration (MDA) with annual single dose of 6 mg/kg body weight of DEC tablets in all LF endemic districts including Surat city. Four rounds of MDA (2004-2007) had shown 41% reduction in mf rate, with drastic reduction in infection rate of 88% and 100% in infectivity rate. Serious adverse effect (SAE) after 4th round of MDA was insignificant (< 0.5%) during 2007. An assessment by surveying 5058 people in different parts of Surat city revealed the drug distribution coverage of more than 95% but actual drug compliance between 70-90%. Analysis of the data revealed that though the overall Microfilaria rate has been reduced due to MDA, higher Microfilaria rate was noticed in North zone of city where the migrant populations influx is higher. The observation and analysis of the data in Surat city towards elimination of Lymphatic filariasis has been discussed in this paper.

Estimation of malaria mortality of A District in India during 2010 by using three models.

There is no standard method for estimating annual malaria deaths in India. The degree of under-reporting in routine system is uncertain with a varied picture of 10, 15, 25 and 200 times as found in different studies/models. During October 2010 a community based cross-sectional survey was conducted by National Vector Borne Disease Control Programme (NVBDCP) in 32 villages of West Garo Hills district of Meghalaya. 'Gap filling', 'fever survey' and 'verbal autopsy' models, developed in NVBDCP were used on the data obtained from two surveys done simultaneously: 'fever survey' with 2 weeks recall period and 'death survey' with one year recall period. Inputs from demographic and epidemiological data of the district were also given. During 2010, the district has reported 32 malaria deaths. Degrees of under-reporting found in the study were 6.93, 7.53 and 12 times in three models respectively. The first two models yielded closer estimates. But, verbal autopsy model gave inflated value as the method was unreliable for diagnosing malaria deaths. First two models, if found to be replicable, can be incorporated in NVBDCP activities to evaluate malaria control measures at district level. Verbal autopsy model may be used after concordance study in those districts where Pf malaria cases occur but no death is reported.

Media scanning and verification system as a supplemental tool to disease outbreak detection & reporting at National Centre for Disease Control, Delhi.

Media scanning for unusual health events can efficiently supplement conventional communicable disease surveillance systems for early detection and response to outbreaks. There is a need to rapidly process and appropriately disseminate the media reports on unusual health events for timely action. Hence to address this need in India a Media Scanning & Verification Cell (MSVC) was established in July 2008 at the National Centre for Disease Control, Delhi. MSVC is supervised by Epidemiologists working in Central Surveillance Unit of IDSP. This unique system monitors Global and National Media sources such as National and Regional print media, news on internet, news wires and websites, news channels and news shared by partners like Global Public Health Intelligence Network (GPHIN), Canada, WHO and other International and national agencies. The information is shared to the districts affected and District Surveillance Officer (DSO) and his team is expected to investigate and revert through the internet about the correctness and action taken. A mean number of 4 Media Alert reports are generated each day. A total of 1685 alerts were reported in a period between July 2008 to December 2011. Of these 1241 (73.7%) were verified as real events and 183 (10.9%) were considered outbreaks by local health officials. Most events were captured through internet (57%) followed by the print media (24%). The most common disease events identified were food-borne and diarrhea (29.1%), dengue (10.68%), influenza & respiratory disease (8.1%) and malaria (7.4%). The sensitivity of MSVC to detect outbreaks was 14.8% with more than half of outbreaks detected before they were identified by the conventional surveillance system. It has proven to be a highly effective supplemental tool to official surveillance system in the detection of early warning signals and hence timely detection and management of public health threats in India.