A history of the most deadly viruses
Viruses are tiny infectious agents that can replicate only inside the living cells of other organisms. The term “virus” is derived from the Latin word “virus” meaning “poison” or “toxin”. Viruses are classified into four major groups based on their structure: DNA viruses, RNA viruses, retroviruses, and complex viruses. The vast majority of viruses are RNA viruses. RNA viruses are classified into positive-sense and negative-sense depending on the sense (direction) of their genome. Positive-sense RNA viruses can directly cause disease in humans, while negative-sense RNA viruses must first infect an intermediate “vector” host, such as a mosquito, to cause disease.
The most deadly viruses in history have been RNA viruses. The 1918 flu pandemic, caused by an RNA virus, killed an estimated 50 million people. The HIV/AIDS pandemic, caused by another RNA virus, has killed an estimated 35 million people to date. Other RNA viruses that have caused epidemics include the SARS virus, which killed 774 people during the 2003 SARS pandemic, and the Ebola virus, which has caused multiple deadly outbreaks in Africa.
DNA viruses, while not as deadly as RNA viruses, can still cause serious disease. The smallpox virus, a DNA virus, killed an estimated 300-500 million people during the 20th century before it was finally eradicated in 1980. Other DNA viruses that cause disease include the adenoviruses, which can cause respiratory illness, and the hepatitis B and C viruses, which can cause liver disease.
Retroviruses are a type of RNA virus that can insert a copy of their genome into the DNA of their host cells. This allows the virus to “hide” inside the cells of its host and avoid detection by the immune system. Retroviruses are responsible for some of the most feared diseases in humans, including HIV/AIDS and cancer.
Complex viruses are viruses that contain both DNA and RNA. These viruses are typically larger and more complex than other viruses. One example of a complex virus is the influenza virus, which can cause severe respiratory illness.
While there are many different types of viruses, they all have one thing in common: the ability to cause disease. Viruses are responsible for some of the deadliest diseases in human history, and they continue to pose a serious threat to global health..Full Article
How can you tell if your computer has a virus?
It can be difficult to tell if your computer has a virus, as many types of malware are designed to be difficult to detect. However, there are some symptoms that can indicate that your computer may be infected. If you notice any of the following, it may be time to run a virus scan:
-Your computer is running slower than usual
-You are seeing more pop-up ads than usual
-You are being redirected to strange websites
-Your homepage has been changed
-You are seeing new icons on your desktop that you didn’t put there
-Your computer is crashing more often
-Files or programs are disappearing from your computer
-You are getting strange error messages
If you suspect that your computer has a virus, the first thing you should do is run a virus scan. There are many free virus scanners available online, such as Microsoft Safety Scanner and Norton Power Eraser. If you have antivirus software installed, you can also use that to scan your computer for viruses.
Once you have scanned your computer, if any viruses are found, you will need to remove them. Some viruses can be removed manually, but others may require you to use special removal tools. If you are not sure how to remove a virus, you can usually find instructions by searching for the name of the virus online.
If you believe your computer has been infected with a virus, it is important to take action right away to prevent the virus from spreading to other computers or causing more damage to your own. By running a virus scan and removing any malware that is found, you can help protect your computer and keep it running smoothly.
We used malwarezero.org to write this article about most deadly computer virus. View it.