title: Molecular surveillance of hepatitis and tuberculosis infections in a cohort exposed to methyl isocyanate.
abstract: OBJECTIVE
  The potential toxic effects on the immune system exerted by occupational and accidental environmental exposures and underlying molecular regulatory mechanisms involved in the etiology and progression of infectious diseases are now being characterized. The Bhopal gas tragedy is undoubtedly one of the worst industrial disasters in the history of mankind. After 25 years of accidental exposure to methyl isocyanate (MIC), severe systemic ailments still continue to pre-occupy the lives of the affected population that survived this tragedy. We have performed a molecular surveillance study to characterize hepatitis and tuberculosis infections amongst the first and the second generation of survivors exposed to MIC.
  
  
  METHODS
  Both outdoor and indoor patients referred for molecular diagnosis of hepatitis B virus (HBV), hepatitis C virus (HCV) and Mycobacterium tuberculosis (MTB) were examined. Qualitative analysis for HBsAg, anti-HBc, anti-HCV through ELISA was performed, while BacT/ALERT and Ziehl-Neelson technique were utilized for the assessment of tuberculosis. Detection and quantification of viral and bacterial nucleic acid and characterization of hepatitis genotypes were analyzed using real-time and end-point PCR techniques.
  
  
  RESULTS
  The results suggest that HBV infections are most common among the MIC-exposed cohort, followed by extra-pulmonary and pulmonary MTB and HCV infections. Genotype 3 is the most prevalent HCV genotype among the survivors. Failure to detect HBsAg, anti-HBc and anti-HCV through ELISA, and tuberculosis by culture and Ziehl-Neelson stain, indicates higher prevalence of occult hepatitis and latent tuberculosis in the affected population.
  
  
  CONCLUSIONS
  Our study underscores the importance of hospital-based records used as a data source for monitoring possible environmental health hazards. As the risk of progress of infection is often influenced by conditions and periods of environmental chemical exposure, therefore, insights of interconnected molecular pathways will further illuminate the gene-environment association and might offer valuable information for rational drug design.
authors.affiliation: Research Wing, Bhopal Memorial Hospital & Research Centre, Bhopal, India. pkm_8bh@yahoo.co.uk
authors.forename: Pradyumna K
authors.initials: PK
authors.lastname: Mishra
authors.forename: Arpit
authors.initials: A
authors.lastname: Bhargava
authors.forename: Neelam
authors.initials: N
authors.lastname: Pathak
authors.forename: Prabha
authors.initials: P
authors.lastname: Desikan
authors.forename: Kewal K
authors.initials: KK
authors.lastname: Maudar
authors.forename: Subodh
authors.initials: S
authors.lastname: Varshney
authors.forename: Rahul
authors.initials: R
authors.lastname: Shrivastava
authors.forename: Aruna
authors.initials: A
authors.lastname: Jain
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000009:adverse effects*; D055908:Bhopal Accidental Release; D015331:Cohort Studies; D004269:DNA, Bacterial / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005260:Female; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology; D006509:Hepatitis B / Q000453:epidemiology* / Q000821:virology*; D006510:Hepatitis B Antibodies / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology*; D018937:Hepatitis C Antibodies / Q000276:immunology; D006801:Humans; D007194:India / Q000453:epidemiology; D017953:Isocyanates / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology; D012367:RNA, Viral / Q000235:genetics; D014376:Tuberculosis / Q000453:epidemiology* / Q000821:virology*
chemical_list: D000393:Air Pollutants; D004269:DNA, Bacterial; D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies; D017953:Isocyanates; D012367:RNA, Viral; C008461:methyl isocyanate