Anthrax
...xplore is the finding of two studies. One was done on the virulence of anthrax. One on the treatment methods i.e.: anthrax vaccines and finally and finally how sever is the threat of anthrax from a biological warfare standpoint? Virulence Virulence studies of anthrax are important for many reasons, information is one also what we learn from the virulence studies can be useful in the case of biological warfare. Virulence studies can lead to the development of more efficient vaccines. According to the journal of clinical microbiology, B. anthraces virulence is associated with the clonality and virulence of plasmids PXOI and PXO2. Plasmid PXO2 carries the genes required for synthesis of antiphagoctyic poly-D-glutamic and acid capsule facilitating host immune. PXO1 is required for the synthesis of three anthrax toxic protein antigen These proteins in return act in binary combination to produce the two anthrax toxins, edema toxin and lethal toxin. For this experiment anthrax toxins were not the main focus as they have been explored and researched extensively in the past, it is the copy number of plasmids that are the center of attention. For this study they used guinea pigs vaccinated with the human vaccine (AVA) they also used 20 genetically diverse B. anthraces isolates. To determine the plasmid copy numbers present per cell (one for PXO1, second for PXO2) they also used absolute QPCR analysis. By the combining data from challenge studies of AVA vaccinated guinea pigs and data from the plasmids PXO1 and PXO2 copy numbers from a genetically diverse set of isolates. Using all this they were able to come up with a model this is predictive of virulence. They then used model to compare the predicted and observed survival rates of AVA-vaccinated guinea pigs when challenged with a set of randomly chosen isolates. The integrity of the model was validated by using a randomly chosen set of 12 additional B. anthraces isolates. Since plasmid copy numbers is an area that the science community has not explored very often they were able to make significant discoveries. 1. Using the relatively new molecular detection system QPCR, they were able to put to sleep a common theory which was that B. anthraces contains only one copy of each plasmid. Their results showed that there are as much as 243 copies of PXO1 and 32 copies of PXO2 per cell. 2. Their results also indicated that the number of PXO2 plasmids in each bacterial cell contributes to the level of virulence associated with the isolate. PXO2 plays a significant role in the virulence and can contribute to observed variations in virulence. 3. The model they developed indicated that PXO1 numbers does not have significant contribution to virulence. Vaccine Anthrax vaccine works the same way as tetanus, rabies and other common vaccines. Anthrax vaccine causes the body to make protective antibodies. Then the antibodies protect the person by circulating in the blood stream and hunting down anthrax germs. The antibodies attack anthrax germs long after the person has been vaccinated. Anthrax vaccine is made from a strain of anthrax bacteria that cannot cause anthrax, for this reason it is referred to as an inactive vaccine. Study after study has shown that anthrax vaccine’s is safe. The anthrax vaccine licensed for people requires a six dose primary series. Anthrax vaccine absorbs (AVA) has an aluminum hydroxide-precipitated bacillus anthraces cell-free filtrate and was licensed in 1970 by the FDA. The only problem with the current vaccine is that it requires three inoculations given at first day, 14th day and 28th day. This is followed by three booster inoculations. Given at 6th month, 12th month and 18th month. In a recent study scientists set out to come up with a less reactogenic vaccine requiring fewer inoculations and boosters. This would lead to an anthrax vaccine that would be more practical, more benefical and easier to administer to patients. Not to mention the mass public should there be a biological attack on a major city. Venezuelan equine encephalitis (VEE) virus has been configured for the use as a vaccine vector for a wide variety of immunogens. VEE is made up of self replicating RNA called replicon. ...