Severity of dengue illness and presence of anti DV IgG in serum of laboratory confirmed dengue cases.

BACKGROUND & OBJECTIVES: Presence of dengue is reported from India since 1960s. Secondary dengue infection may be more severe than primary, hence, distinction between primary and secondary dengue is essential. A way to detect secondary dengue is demonstration of anti DV IgG in patients' serum. In this study we explored the association of dengue severity with anti DV IgG positivity. METHODS: Laboratory confirmed cases of dengue (positive for anti DV IgM/ NS-1 Antigen/ DV -RNA), presenting to the hospital within 7 days of illness, were consecutively enrolled for a period of one month (September 1-30, 2018) and were tested for anti DV IgG in their serum. All PCR positive samples were serotyped. Cases positive for anti-dengue IgG were labeled as secondary cases. Clinical details were collected to assess the severity of illness. Association of dengue severity with anti DV IgG positivity was calculated. RESULTS: Of the 128 dengue positive cases, 89 (69.5%) were anti DV IgM positive, 72 (56.3%) were Dengue NS-1 positives and 37 (28.9%) were DV-RNA positive. Only 39 (30.5%) cases were having detectable anti-dengue IgG in their serum (secondary dengue). Anti-dengue IgM positivity was significantly higher in secondary dengue cases. No association of anti DV IgG positivity was seen with severity of dengue illness. INTERPRETATION & CONCLUSION: No association of IgG positivity with severity of illness was seen. D4 serotype is first time reported from Uttar Pradesh, India.

Observation on dengue cases from a virus diagnostic laboratory of a tertiary care hospital in North India.

BACKGROUND & OBJECTIVES: The epidemiology of dengue fever (DF) is complex in the Indian subcontinent as all the four serotypes are circulating. This study reports observations on dengue cases from a virus diagnostic laboratory of a north Indian tertiary care hospital catering to areas in and around Lucknow, Uttar Pradesh. METHODS: Serum samples were obtained from suspected cases of dengue referred to the virus diagnostic laboratory during 2011 to 2013, and detailed history was taken on a pre-structured datasheet. All samples were tested for anti-dengue virus (DV) IgM antibodies and DV-non structural protein 1 antigen (NS1Ag) by ELISA. NS1Ag positive samples were tested further by conventional RT-PCR for DV-RNA detection and serotyping. RESULTS: Of the 4019 suspected patients of dengue, 886 (22%) showed laboratory evidence of dengue virus infection. Of these, 19, 17 and 27 per cent were positive in 2011, 2012 and 2013, respectively. Children and adults were similarly affected by dengue in all the three years. Males were more commonly affected than females. The predominant DV serotype detected was DV-2, DV-1 and DV-3 in 2011, 2012 and 2013, respectively. DV-4 serotype was not detected. About half the cases positive for DV infection, showed symptoms of dengue with warning signs/ severe dengue. A distinct seasonality with increase in number of dengue cases in the post monsoon period was seen. INTERPRETATION & CONCLUSIONS: Change in circulating serotype of dengue virus; a distinct adult dengue involvement; and a remarkable number of cases presenting with severe dengue manifestations are the main findings of this study.

Molecular characterisation of Hepatitis E virus isolates from north India.

PURPOSE: Hepatitis E virus (HEV) is responsible for >50% of acute viral hepatitis (AVH) in developing countries. It has 4 major genotypes and various subtypes which vary in geographical distribution, clinical manifestations and epidemiological patterns. This study was conducted to characterise HEV isolates from north India to study the effect of host and viral factors on HEV infection. METHODS: Serum samples collected from 536 AVH patients admitted to Department of Medicine, King George's Medical University, Lucknow from July 2016 to June 2017 were screened for anti HEV IgM, anti HAV IgM, HBsAg and anti HCV antibodies using commercial ELISA kits. Samples either positive for anti HEV IgM antibodies (n â€‹= â€‹204) or negative for all 4 hepatotropic viruses (n â€‹= â€‹37) were enrolled and tested by real time PCR for HEV RNA. HEV RNA positive samples with high viral load were further subjected to nested PCR for amplification of capsid gene. Sequencing and phylogenetic analysis were performed. HEV strains isolated from this study were deposited to GenBank under accession numbers MG571274 to MG571283. RESULTS: Anti HEV IgM positivity was observed among 38% clinically suspected AVH cases. HEV RNA was detected in 31.8% seropositive HEV cases and additional 3 seronegative cases. Males outnumbered females and the most affected age group was of young adults. Maximum number of cases were seen during the months of June to September. Phylogenetic analysis showed that HEV strains in our study belonged to genotype 1a. Mortality in HEV infected pregnant females was 23.5% as compared to 2.4% in non-pregnant females. Adverse fetal outcome was recorded in 51% of HEV infected pregnancies. CONCLUSIONS: HEV genotype 1a is prevalent in our setting. HEV during pregnancy is associated with adverse maternal and fetal outcome.

Incidence and progression of Parvovirus B19 infection and molecular changes in circulating B19V strains in children with haematological malignancy: A follow up study.

The present study was planned to estimate the incidence of human Parvovirus B19 infection and understand its progression in children suffering with hematological malignancy. The circulating B19V genotypes and viral mutations occurring in strains of B19V over one-year period were also studied. Children with malignancies were enrolled consecutively and were followed up for one-year period. Serum sample was collected at the time of enrolment and each follow up visit and was tested for anti B19V IgG and IgM as well as for B19V DNA. At least one B19V DNA positive sample from each patient was processed for sequencing. For patients positive for B19V DNA >1 time and at least 6 months apart, last positive sample from the same patient was also sequenced to study the nucleotide change over time. We have found very high incidence of B19V infection (100%) in the study population. All the patients tested positive for at least one B19V infection parameter (either antibodies or DNA) at least once, over one year of follow up. Cumulative percent positivity of anti B19V IgG, anti B19V IgM and B19V DNA was 85.3%, 45.2% and 72.1% respectively. Genotype 3b was reported, with occasional nucleotide change over one year period. DNA clearance was delayed in spite of appearance of IgG antibodies. Appearance of IgM class of antibodies was either delayed or absent. To conclude, children with haematological malignancies have high incidence of B19V infection with late and short lived serological response and persistence of DNA for long duration.

Epidemiology and etiology of acute encephalitis syndrome in North India.

Acute encephalitis syndrome (AES) is a major public health problem in eastern Uttar Pradesh, claiming thousands of lives every year. Here we report the common viral etiologic agents of AES and its epidemiology in the vicinity of Lucknow in Uttar Pradesh, North India. Cerebrospinal fluid (CSF) samples collected from patients with AES, who were referred to a viral diagnostic laboratory from January 2011 to December 2012, were tested for IgM antibodies against Japanese encephalitis virus (JEV), dengue virus (DV), herpes simplex virus (HSV), measles virus, mumps virus, varicella zoster virus (VZV), and enterovirus using commercial enzyme immuno-assays. Of the 1,578 enrolled patients, JEV was the most commonly detected (16.2%), followed by DV (10.8%), HSV (9.3%), measles virus (8.9%), mumps virus (8.7%), VZV (4.4%), and enterovirus (0%). Co-positivity with more than 1 virus was observed in 12 patients. The demographic distribution of patients pertaining to age, sex, and geographic and seasonal variation is discussed. Maximum mortality was caused by JEV infection, while patients with HSV infection had maximum residual neuro-psychiatric disability. JEV and DV are the chief causative agents of AES in North India, although other viruses should also be considered in a differential diagnosis.

Co-positivity of anti-dengue virus and anti-Japanese encephalitis virus IgM in endemic area: co-infection or cross reactivity?

OBJECTIVE: To report high co-positivity of anti-dengue virus (DV) and anti-Japanese encephalitis virus (JEV) IgM in an area endemic for both the viruses and to discuss the possibilities of co-infection. METHODS: Serum samples from the patients who presented with fever, suspected central nervous system infection and thrombocytopenia, were tested for anti-DV IgM and anti-JEV IgM antibodies. Conventional reverse transcriptase polymerase chain reaction was done for detection of DV RNA and JEV RNA. RESULTS: Of 1 410 patient sera tested for anti-DV and anti-JEV antibodies, 129 (9.14%) were co-positive for both. This co-positivity was observed only in those months when anti-JEV IgM positivity was high. Titers of both anti-DV IgM and anti-JEV IgM were high in most of the co-positive cases. Among these 129 co-positive cases, 76 were tested by conventional reverse transcriptase polymerase chain reaction for both flaviviruses, of which eight cases were co-positive for DV and JEV. CONCLUSIONS: Co-infection with more than one flavivirus species can occur in hyperendemic areas.

Human parvovirus B19 associated dilated cardiomyopathy.

We describe two children presenting with acute left ventricular dysfunction. Both cases had evidence of dilated cardiomyopathy, requiring inotropic support and were tested for cardiotropic viruses by conventional or real-time polymerase chain reaction using specific primers for enteroviruses, human parvovirus B19, Adenoviruses, Epstein-Barr virus (EBV), herpes simplex viruses 1 and 2 (HSV), human herpes virus-6 (HHV-6) and cytomegalovirus (CMV). IgG and IgM antibodies against parvovirus B19, EBV, HSV and CMV were also tested by ELISA. One case tested positive for parvovirus B19 infection and recovered completely within 6 months in absence of any specific therapy. The other case tested positive for parvovirus B19 infection in association with hypocalcaemia and was cured following standard heart failure therapy along with calcium and vitamin D supplementation. Sequence analysis of DNA products from both patients revealed genotype 3. To best of our knowledge this is first report of circulating genotype 3 from India.