Today, The Grandma has been reading about computer viruses. She has remembered ElkCloner, one of the first known microcomputer viruses written by Richard Skrenta on a day like today in 1982.
Elk Cloner is one of the first knownmicrocomputerviruses that spread in the wild,i.e., outside the computer system or laboratory in which it was written. It attached itself to the Apple II operating system and spread by floppy disk. It was written around 1982 by programmer and entrepreneur Rich Skrenta as a 15-year-old high school student, originally as a joke, and put onto a game disk.
Elk Cloner spread by infecting the Apple DOS 3.3 operating system usinga technique now known as a boot sector virus. It was attached to a game which was then set to play.
The 50th time the game was started, the virus was released, but instead of playing the game, it would change to a blank screen that displayed a poem about the virus. If a computer booted from an infected floppy disk, a copy of the virus was placed in the computer's memory. When an uninfected disk was inserted into the computer, the entire DOS (including Elk Cloner) would be copied to the disk, allowing it to spread from disk to disk. To prevent the DOS from being continually re-written each time the disk was accessed, Elk Cloner also wrote a signature byte to the disk's directory, indicating that it had already been infected.
The poem that Elk Cloner would display was as follows:
ELK CLONER: THE PROGRAM WITH A PERSONALITY IT WILL GET ON ALL YOUR DISKS IT WILL INFILTRATE YOUR CHIPS YES IT'S CLONER! IT WILL STICK TO YOU LIKE GLUE IT WILL MODIFY RAM TOO SEND IN THE CLONER!
Elk Cloner did not cause deliberate harm, but Apple DOS disks without a standard image had their reserved tracks overwritten.
Elk Cloner was created by Skrenta as a prank in 1982. Skrenta already had a reputation for pranks among his friends because, in sharing computer games and software, he would often alter the floppy disks to shut down or display taunting on-screen messages. Due to this reputation, many of his friends simply stopped accepting floppy disks from him.
Skrenta thought of methods to alter floppy disks without physically touching or harming them. During a winter break from Mt. Lebanon High School in Mt. Lebanon, Pennsylvania, Skrenta discovered how to launch the messages automatically on his Apple II computer. He developed what is now known as a boot sector virus, and began circulating it in early 1982 among high school friends and a local computer club. Twenty-five years later, in 2007, Skrenta called it some dumb little practical joke.
According to contemporary reports, the virus was rather contagious, successfully infecting the floppies of most people Skrenta knew, and upsetting many of them.
Part of the success was that people were not at all wary of the potential problem, nor were virus scanners or cleaners available. The virus could be removed using Apple's MASTER CREATE utility or other utilities to re-write a fresh copy of DOS to the infected disk.
Furthermore, once Elk Cloner was removed, the previously-infected disk would not be re-infected since it already contained the Elk Clonersignature in its directory. It was also possible to inoculate uninfected disks against Elk Cloner by writing the signature to the disk; the virus would then think the disk was already infected and refrain from writing itself.
I think computer viruses should count as life. I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image.
The Grandma is knocked out. She's suffering the consequences of the flu and she's totally destroyed. Yesterday, she started feeling the first symtomps and she went to her local medical center.
While she was waiting for her turn, she had enough force to study a new lesson of her Elementary Language Practice manual (Grammar 23).
After visiting the doctor, The Grandma is following her instructions: stay at bed, take warm drinks and take some medicines. It's a matter of time, more or less seven days, to stay fine again and ready to continue with her normal life.
Influenza, commonly known as the flu, is an infectious disease caused by an influenza virus. Symptoms can be mild to severe. The most common symptoms include: high fever, runny nose, sore throat, muscle pains, headache, coughing, sneezing, and feeling tired. These symptoms typically begin two days after exposure to the virus and most last less than a week. The cough, however, may last for more than two weeks.
In children, there may be diarrhea and vomiting, but these are not common in adults. Diarrhea and vomiting occur more commonly in gastroenteritis, which is an unrelated disease and sometimes inaccurately referred to as stomach flu or the 24-hour flu. Complications of influenza may include viral pneumonia,secondary bacterial pneumonia, sinus infections, and worsening of previous health problems such as asthma or heart failure.
Analyzing flu symptoms
Three of the four types of influenza viruses affect people, Type A, Type B, and Type C. Type D has not been known to infect people, but is believed to have the potential to do so. Usually, the virus is spread through the air from coughs or sneezes. This is believed to occur mostly over relatively short distances. It can also be spread by touching surfaces contaminated by the virus and then touching the mouth or eyes.
A person may be infectious to others both before and during the time they are showing symptoms. The infection may be confirmed by testing the throat, sputum, or nose for the virus. A number of rapid tests are available; however, people may still have the infection even if the results are negative. A type of polymerase chain reaction that detects the virus's RNA is more accurate.
Frequent hand washing reduces the risk of viral spread. Wearing a surgical mask is also useful. Yearly vaccinations against influenza are recommended by the WorldHealth Organization for those at high risk. The vaccine is usually effective against three or four types of influenza. It is usually well-tolerated. A vaccine made for one year may not be useful in the following year, since the virus evolves rapidly. Antiviral drugs such as the neuraminidase inhibitor oseltamivir, among others, have been used to treat influenza. The benefit of antiviral drugs in those who are otherwise healthy do not appear to be greater than their risks. No benefit has been found in those with other health problems.
Following the doctor's advice
Influenza spreads around the world in yearly outbreaks, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths. About 20% of unvaccinated children and 10% of unvaccinated adults are infected each year. In the northern and southern parts of the world, outbreaks occur mainly in the winter, while around the Equator, outbreaks may occur at any time of the year. Death occurs mostly in the young, the old, and those with other health problems. Larger outbreaks known as pandemics are less frequent.
In the 20th century, three influenza pandemics occurred: Spanish influenza in 1918, ~50 million deaths, Asian influenza in 1957, two million deaths, and Hong Kong influenza in 1968, one million deaths. The World Health Organization declared an outbreak of a new type of influenza A/H1N1 to be a pandemic in June 2009. Influenza may also affect other animals, including pigs, horses, and birds. Approximately 33% of people with influenza are asymptomatic.
Symptoms of influenza can start quite suddenly one to two days after infection. Usually the first symptoms are chills and body aches, but fever is also common early in the infection, with body temperatures ranging from 38 to 39 °C, approximately 100 to 103 °F. Many people are so ill that they are confined to bed for several days, with aches and pains throughout their bodies, which are worse in their backs and legs.
-Reddened eyes, skin (especially face), mouth, throat and nose
-Petechial rash
In children, gastrointestinal symptoms such as vomiting, diarrhea, and abdominal pain, may be severe in children with influenza B.
It can be difficult to distinguish between the common cold and influenza in the early stages of these infections. Influenza is a mixture of symptoms of common cold and pneumonia, body ache, headache, and fatigue. Diarrhea is not usually a symptom of influenza in adults, although it has been seen in some human cases of the H5N1 bird flu and can be a symptom in children.
Surviving the flu at home
When an infected person sneezes or coughs more than half a million virus particles can be spread to those close by. In otherwise healthy adults, influenza virus shedding, the time during which a person might be infectious to another person, increases sharply one-half to one day after infection, peaks on day 2 and persists for an average total duration of 5 days, but can persist as long as 9 days. In those who develop symptoms from experimental infection, only 67% of healthy experimentally infected individuals, symptoms and viral shedding show a similar pattern, but with viral shedding preceding illness by one day.
Children are much more infectious than adults and shed virus from just before they develop symptoms until two weeks after infection. In immunocompromised people, viral shedding can continue for longer than two weeks.
-By direct transmission, when an infected person sneezes mucus directly into the eyes, nose or mouth of another person;
-The airborne route, when someone inhales the aerosols produced by an infected person coughing, sneezing or spitting;
-Through hand-to-eye, hand-to-nose, or hand-to-mouth transmission,either from contaminated surfaces or from direct personal contact such as a hand-shake.
Reasonably effective ways to reduce the transmission of influenza include good personal health and hygiene habits such as: not touching your eyes, nose or mouth; frequent hand washing, with soap and water, or with alcohol-based hand rubs; covering coughs and sneezes; avoiding close contact with sick people; and staying home yourself if you are sick. Avoiding spitting is also recommended. Although face masks might help prevent transmission when caring for the sick, there is mixed evidence on beneficial effects in the community.
Smoking raises the risk of contracting influenza, as well as producing more severe disease symptoms.
