 |
| About Bioline | All Journals | Testimonials | Membership | News |
|
||||||
|
||||||
Indian Journal of Medical Microbiology, Vol. 23, No. 4, October-December, 2005, pp. 271-272 Correspondence Strengthening microbial forensics to counter bioterrrorism Pattnaik P Corresponding author (email:< p.pat@rediffmail.com>) Code Number: mb05082 Dear Editor, A number of bacteria, viruses and toxins pose serious health concerns to humans, that threatens country′s agricultural economy and food supply and affects the environment. The potential for use of any of these pathogenic agents as biological weapon has been demonstrated.[1] There are examples of well-developed practices for handling and analyzing pathogenic agents. However, many of these assays address epidemiological concerns and do not provide sufficient information on the strain or isolate and source of the pathogen so that the law enforcement authorities can better identify the source or culprit. In the arena of emerging microbial diseases, these critical issues are addressed with increasing frequency using molecular microbial signatures. Criminal justice system experienced a shift from reliance on biological phenotypes of the suspected perpetrator, such as finger prints, towards more reliable and quantifiable molecular markers, such as polymorphisms (variation) in the DNA sequence. Microbial forensics is for detection of reliably measured molecular variations between related microbial strains and their use to infer the origin, relationships and, transmission routes of the particular isolate. These variations or markers include genome sequence polymorphisms, which can be detected by direct sequencing or by hybridization based methods. Genome wide patterns of gene expression can be easily measured with DNA microarray and differences in protein or small-molecule patterns can be detected by spectroscopic or other methods. Application of molecular markers in microbial forensic studies has led to some high profile discoveries. Sequencing of amplified viral fragments from the dentist and the infected patients of Florida, USA led to the discovery of transmission of HIV from the dentist to several patients.[2] Anthrax spores recovered from a vial of slime scraped 10 years ago from the walls of a Japanese doomsday cult′s Tokyo headquarters pinpointed the specific strain harbored by the terrorists. The same was confirmed by using multiple-locus variable number tandem repeat (VNTR) analysis and the Aum Shinrikyo B. anthracis bioterror strain was identified as Sterne 34F2.[3] The investigation on the West Nile virus outbreak in the northern US in the year 1999 eventually revealed a single strain from birds and humans in New York with greatest similarity to a strain originally isolated from dead goose in Israel, leading to the conclusion that the outbreak was of natural origin.[4] Comparative evaluation of full-genome sequencing of two related B. anthracis strains revealed comprehensive identification of genetic polymorphism.[5] Other than whole genome sequencing, many a times comparative evaluation of specific gene targets having more number of synonymous mutations has been explored for molecular typing and tracing the source of pathogens in disease outbreaks. The new discipline of microbial forensics is a conglomeration of an array of well established fields, such as microbial genomics, phylogenetics, forensic informatics and classical microbiology. Unlike public health investigations, microbial forensic investigation goes further to associate the source of the causative agent with a specific individual or group. Microbial forensics will be most effective if there is sufficient basic scientific information concerning microbial genetics, evolution, physiology and ecology. A scientific assessment on microbial forensics released by American Academy of Microbiology pointed out that, simply studying the pathogen without understanding biotic and abiotic environmental backgrounds will lead to false confidence in our ability to detect it. Molecular techniques have been used for years to trace outbreaks of microbial diseases, a practice called molecular epidemiology. In fact, there are currently surveillance systems that store and make available DNA fingerprints for microbes that are likely to be involved in nosocomial infections and food borne infections. PulseNet of the U.S. Centre for Disease Control (CDC), is one of such surveillance system for tracking infections such as Salmonella . Clearly, biological weapons are assigned high priority in homeland security, defence, counterproliferation, nonproliferation, intelligence and counterterrorist programmes, resources and policies. In order to strengthen its active defence against intentions, development, and use of these weapons, it is now time for the world community to establish a comprehensive forensic capability to effectively attribute biological weapons for investigative, intelligence, prosecutive, diplomatic, and policy purposes. Nevertheless, aggressive research programme are needed for forensic trace, microchemical analysis, trace evidence analysis coupled with microbial forensics so that the discipline of microbiology and/or forensic science will grow and bear fruit for national security References
Copyright 2005 - Indian Journal of Medical Microbiology |
| |||||||||
