Trend analysis in seroprevalence of dengue, chikungunya and malaria: A seven-year serological study from a tertiary care hospital of Maharashtra, India.

BACKGROUND & OBJECTIVES: Dengue, chikungunya and malaria are mosquito-borne infections, which have shared endemicity and similar clinical presentation. Simultaneous co-infection with more than one infectious agent complicates the diagnosis and further course of treatment. This study aims to determine the seroprevalence and trend of malaria, dengue and chikungunya from 2014-2020 in a tertiary care hospital of western India. METHODS: The present study was retrospective descriptive record-based. Serum samples from clinically suspected dengue and chikungunya were subjected to both IgM antibody capture ELISA kits produced by National Institute of Virology (NIV), Pune, India. They were also subjected to ELISA based NS1Ag testing. In Suspected malaria cases, blood collected in EDTA tubes was subjected for Rapid Malaria antigen testing. Statistical analysis was performed using MS Excel and JMP Software. RESULTS: Seropositivity of malaria was comparatively higher in 2014 (5.53%) and a decreasing trend was observed in subsequent years. Majority of malarial infections were caused by Plasmodium vivax (81.67%). There is drastic increase in seropositivity of chikungunya from 2016 (23.67%) and thereafter as compared to 2014 (6.57%) and 2015 (7.29%) indicating its re-emergence. The dengue seropositivity in 2019 (40.19%) was highest in last seven years. Males were predominantly affected, and most affected age group was 21-30 years. Peak transmission was observed in post-monsoon seasons. Dengue and chikungunya co-infection was observed to be 5.79%. INTERPRETATION & CONCLUSION: This study emphasizes the importance of surveillance studies to understand the trend of vector-borne diseases for prompt diagnosis, management of patients in hospital setup and for early detection and curtailment of outbreaks and epidemics by public health sectors through appropriate vector control programs.

Bacteriological Study Among Influenza-like Illness Cases in a Community Setting in Pune, India.

Influenza-like illness (ILI) and acute respiratory infection (ARI) are common presentations during winter, and indiscriminate antibiotic use contributes significantly to the emerging post-antibiotic era. Although viral agents causing ILI are predominant, they are indistinguishable from the bacterial agents based on the clinical features alone. The present study was aimed at determining the bacterial agents associated with ILI and their susceptibility pattern during a study done in a community setting in Pune during a surveillance of ILI between March 2013 to November 2016. Throat swabs from 512 suspected ILI cases were processed, and organisms were identified by the standard conventional method. An antimicrobial susceptibility testing was done as per the Clinical Laboratory Standard Institute (CLSI) guidelines. The patients comprised 238 males and 274 females with the majority (38.7%) in the age group of ≤10 years. Bacteria could be isolated from 9.8 % of the patients. The predominant bacteria included beta-hemolytic Streptococcus (42%) followed by group G Streptococcus (30%) and group A Streptococcus (20%). All organisms were sensitive to Penicillin except two isolates of Staphylococcus aureus (50%). Tetracycline (98.8%) and ciprofloxacin (87%) were the next most effective drugs. Overall resistance was observed for erythromycin (37%) and co-trimoxazole (32%).

Prevalence and characterization of rotaviruses in children hospitalized for diarrheal disease in a tertiary care hospital, Pune.

BACKGROUND: Diarrhoea remains the second most common cause of death among children below 5 years globally. Among various enteric pathogens, rotavirus appears to be the most important aetiological agent of acute gastroenteritis in infants and young children. Increased understanding of epidemiology of rotavirus infections is needed to improve the vaccine efficacy. AIM: This study aims to determine prevalence rotavirus infection and prevalent circulating strains of rotavirus in and around Pune. SETTING AND DESIGN: Prospective hospital-based study. The study was approved by Institutional Ethical Committee. MATERIALS AND METHODS: Stool samples (n = 100) were collected from children aged <5 years, hospitalised for acute diarrhoea in paediatric ward at a tertiary care hospital. Samples were subjected for rotavirus antigen capture ELISA. The viral RNA was subjected to multiplex reverse transcription polymerase chain reaction to amplify VP7 genotypes G1-G4, G8-G10 and G12 and VP4 genotypes P[4], P[6], P[8], P[9], P[10] and P[11]. Nontypable rotavirus strains were sequenced. RESULTS: About 35% stool samples were positive for rotavirus antigen by ELISA. G9P[4] (28.6%) was found to be the most prevalent rotavirus strain. The detection of emerging strain G12P[6] (14.3%) and rare reassortant strain G9P[4] was the significant finding. CONCLUSION: Genotypes found in circulation are not present in the currently used vaccine. Thus, an emergence of newer genotypes over a period calls for the continued surveillance and genomic characterisation of rotaviruses to improve the vaccine efficacy.

Evaluation of high performance liquid chromatography purified leptospiral antigen for the diagnosis of leptospirosis.

Leptospirosis is a re-emerging infection, and often occurs in outbreaks. Early diagnosis is important for appropriate control measures and treatment. The sensitivity and specificity of the diagnostic test depends on the antigen, which is used for the detection of antibodies. In the present study, an effort was made to purify and characterize leptospiral antigens, and their performance in the laboratory was assessed. Leptospira biflexa semaranga, Patoc was subjected to processing by the heat extraction method, and the crude antigenic preparation was subjected to high-performance liquid chromatography for purification. The purified antigen fractions were subjected to enzyme-linked immunosorbant assay (ELISA) to determine their reactivity. Only the reactive fractions were tested for specificity by ELISA by allowing the fractions to react with positive sera of patients with non-leptospiral illness. H1, the purified antigen fraction of the heat-extracted preparation, was found to be the most reactive and specific of all fractions tested. The protein was found to have a molecular weight of 50 kDa. The performance of H1 in the laboratory was assessed by formulating an in-house ELISA using the H1 antigen. The results were compared with those of microscopic agglutination testing and commercial ELISA. The specificity and sensitivity of in-house ELISA using the H1 antigen were found to be 93.3 and 85.0%, respectively.

Concurrent outbreak of leptospirosis and dengue in Mumbai, India, 2002.

This prospective study was undertaken to investigate the possibility of a concurrent outbreak of leptospirosis and dengue and to describe the clinical illnesses. From 20 June to 14 November 2002, children who presented to our hospital with a suspected diagnosis of leptospirosis or dengue were admitted. In every child with suspected leptospirosis, a screening latex agglutination test was carried out to detect anti-Leptospira antibodies. The diagnosis of leptospirosis was confirmed by a positive enzyme-linked immunosorbent assay (ELISA) test or microagglutination test. The diagnosis of dengue was confirmed by a positive IgM antibody capture ELISA test. Clinical features in the leptospirosis and leptospirosis-negative groups, and dengue and dengue-negative groups were analysed. Of 90 children screened, 15 (16.7 per cent) had leptospirosis. Two children with Weil's disease died and the remaining 13 responded well to intravenous penicillin. Five clinical features were significantly associated with leptospirosis, namely conjunctival suffusion (p=0.007), haemorrhage (p=0.020), abdominal pain (p=0.011), hepatosplenomegaly (p=0.044), and oedema (p=0.007). As the number of these five features concomitantly present increased, the chances of the child having leptospirosis also increased significantly (p<0.0001). Of 90 children screened, 16 (17.8 per cent) had dengue. All responded well to the treatment and went home. Two clinical features were significantly associated with dengue, namely arthralgia (p=0.020) and thrombocytopenia (p=0.001). If both these features were present, the chances of the child having dengue increased significantly (p=0.001). Our study shows that a concurrent outbreak of leptospirosis and dengue had occurred in the slums of Mumbai city.

Leptospiral pneumonia.

Severe leptospirosis rarely presents with primary pulmonary manifestations, without any associated jaundice or renal dysfunction. The authors report a nine-year-old boy who presented with complaints of abrupt onset of high fever; with myalgia, headache, and pain in right chest region, productive cough with hemoptysis and vomiting developing over the past 72 hours. Chest radiograph showed consolidation in the right upper lobe with air bronchogram. A history of contact with sewage water and presence of conjunctival suffusion in a child with pneumonia made us suspect leptospirosis. Following prompt initiation of parenteral penicillin therapy the child's complaints resolved over the next five days. Dri-Dot test to detect anti-Leptospira antibodies was positive. The diagnosis of leptospirosis was confirmed by a positive microagglutination test to Leptospira interrogans serovar Australis by a fourfold rise in antibody titer in paired sera collected during convalescence. Leptospirosis presenting with pulmonary hemorrhage has been associated with significant mortality but it can be successfully treated with early clinical suspicion of alveolar hemorrhage and prompt therapy.

An urban outbreak of leptospirosis in Mumbai, India.

An outbreak of leptospirosis occurred during the rainy season in the city of Mumbai, India. Out of 169 suspected cases, 74 (43.7%) were determined serologically positive by microagglutination test (MAT) carried out with a battery of eight pathogenic serovars, while 78 (46.1%) were shown positive for IgM antibodies to leptospira by enzyme-linked immunosorbent assay. On the basis of MAT, serovar Copenhageni accounted for 66 (89.1%) out of the 74 cases admitted during the period of the outbreak. Myalgia, conjunctival suffusion, cough with hemoptysis, icterus, and oliguria were significantly more common in patients whose samples were determined positive by MAT. The presence of pulmonary signs and symptoms and renal failure were significantly associated with mortality in patients presumed to be suffering from leptospirosis.