What we need to know about the Swine Flu, The origin. It is well known that most higher organisms carry the genomes of certain viruses that normally lie dormant in a quiescent state until they become activated by different factors and causing a number of problems. However in most cases, after infecting their hosts, viruses are cleared by an immunological response mounted by the host or eventually they kill their host this way putting an end to their replication cycle. Yet in either case, the newly produced virus can infect other hosts and start the reproductive cycle once more. Although most viruses have a restricted number of host species that they can infect, some viruses can infect other animal species. The infection of man by viruses from another animal species is known as zoonosis. Influenza virus is one of the best examples known of virus capable of causing a zoonosis, as the infectious virus can also originate from ducks or pigs. Moreover, influenza viruses from humans, swine and different birds can recombine to create new strains with new properties as well as more infectious, virulent and deathly.
About Mexico City. This is a city with over 22 million people, the largest in the western hemisphere and the second largest in the world. It sits at 7,349 feet above sea level in a high plateau. Due to its geographic location, there is no good air movement across it, and high levels of smog hangs over it; thus its inhabitants suffer from a number of respiratory ailments. So perhaps it is no surprising that swine flu started its spread form this city.
How the across species jump may occur? Fluid to fluid contact is what most scientist suspect; animal handlers that are in daily contact slaughtering animals, get the animals blood splashed on them and if an open cut is present on them, then the animal blood can infect them. Over the years, this kind of interaction may be responsible for the virus jumping to a new host, where it can mutate and become pathogenic to the new host.
Transmission. At this point, the infected human can get sick and transmit the virus via aerosolized micro drops of saliva produced during coughing, and he is also capable of passing the virus by direct contact with non-infected people.
About vaccines against it. Currently there are not vaccines against the new swine flu virus strain and producing a vaccine can take 6-9 months. Vaccines against the influenza virus are strain specific, however because the virus has a high rate of mutations in those regions responsible for initiating the infection process there is a need to develop new vaccines every year.
Virulence. The ability for a virus to be more potently infectious; swine flu is intriguing, because it seems that its virulence is of greater power, as compared to other flu’s.
About Tamiflu. ; This drug manufactured by Roche appears to be effective against the swine flu; influenza virus initiates the infection process by latching to sialoglycoproteins present of the cell surface via their neuraminidase. Inhibition of the viral neuraminidase interferes with the infection process contributing to reduce symptoms and complications.
About the Centers for Disease Control. This is a government backed research outfit slocated in Atlanta, Georgia, whose principal mission is to evaluate , research and advise on any and all infectious agents that afflict not only the continental US but the rest of the world also; as the most serious diseases can become pandemic in nature and affect the entire world.. Their website is: www.cdc.gov
Recommendations. What can one do to lower the odds of contacting swine flu?
- Avoid crowded areas
- Avoid contact with infected people
- Wash hands as often as possible
- Avoid captive areas if at all possible, such as planes trains and the like.
Molecular biology of the swine flu. The influenza virus is an enveloped RNA virus and its genome is split between 7 to 8 RNA fragments, each encoding for one to two genes. This large number of RNA fragments allows their mixing or reassorment if more than one virus strain is infecting a cell, to yield new viral strains containing genetic information from different viral strains. As indicated above, the capacity of influenza viruses from different species to exchange genetic information is quite high. Thus as the virus passes from one host species to the next one it would exchange pieces of its gene with other virus to create a genome that is a mosaic of all the viruses from each of the species.
Although the protective immunity stimulated by the vaccines is humoral and mediated by neutralizing antibodies there is significant body of evidence pointing to the crucial role of T cell immunity. In effect, the increased susceptibility of young children and older people correlates well with a low Th1 immunity. A viral peptide responsible for the susceptibility of infected cells to CTLs has been identified. Yet all of the epitopes in the virus responsible for susceptibility to T cell immunity are buried inside the particle and for that reason not available to the action of T cell immunity mediators.