A virus is a tiny submicroscopic parasitic agent which replicates inside an organism’s living cells. Viruses affect all living things, from plants and animals toacteria, including Archaea and eukaryotic bacteria. Most viruses are genetic in nature; this means that, unlike bacteria and other prokaryotes, a virus is coded by its genetic code as a single string of amino acids that can be repeated.
Because a virus is not a living organism (as most viruses are proteins), its location inside an individual organism is highly specific. The location of the virus is also highly related to the host cell it lives in, as is the ability of the virus to replicate and spread between host cells. In order for researchers to study a virus, it must be either bound to a protein or contain enough sequence to be detectable by a compatible sequencing DNA probe. In either case, the virus’ presence must be confirmed with a method called viral RNA detection.
There are three different kinds of DNA probes recommended for viral RNA detection. One is based on a restriction enzyme found in all living things. Another is based on the virus’ amino acid sequences. The last is based on direct fluorescent markers, which can provide results in less than one hour. Of these, the RFLP method is the fastest and most reliable. The restriction enzyme method can provide results in less than thirty minutes, but is not recommended for emergency use.
In the case of live virus-like particles, nucleic acid hybridization experiments are useful to determine if the particles are really virus-like or something else. A specific DNA probe hybridizes to a specific destination on the host cell. When this process occurs, the DNA sequence replicated by the host cell duplicates itself, creating copies of the targeted nucleic acid. In order to see if the target sequence is truly a virus, this technique must be combined with rRT-polymerase chain reactions, which also need to be done as quickly as possible.
It is very important to isolate the genetic material (genetic RNA or DNA) of the virus. For example, in herpes simplex virus infections, it is necessary to isolate the viral RNA or DNA in order to identify and treat infected cells. In addition, medical geneticists use genetic material from patients to try to understand their illnesses. This genetic material can also be used to develop drugs to fight against diseases and to test potential treatments before they are introduced into the market. In the case of emergency medicine, however, the samples of viral RNA or DNA may be collected during a patient’s recovery and used for other purposes.
Other types of bacteria, such as the E-coli and Lactobacillus species, are also studied. These study scientists focus on the ability of these organisms to produce antibodies. In an effort to stop the spread of a disease, researchers produce antibiotics that have been targeted on a particular strain of bacteria, which are then passed on to other susceptible organisms. The antibodies created by these bacteria stop the spread of the pathogen, and this method has been successful in fighting several different infectious agents. Finally, vaccines are developed to prevent several types of diseases. Although these vaccines have prevented several diseases over the years, researchers continue to look for ways to produce a vaccine that will stop the transmission of a particular pathogen.