Elephants rarely get cancer: less than 5% of captive elephants die of cancer, compared to 20% of humans. Elephant genomes have at least 20 copies of the tumour suppressor, p53, which may explain their low cancer rates relative to humans, who have only one copy.
European colonisation of America began in 1492. But how did the Europeans exactly colonise America? What were their tactics? You may be thinking it was due to the help of the Conquistadors or the advanced weaponry. But, something much smaller, in fact microscopic helped Europe colonise America: the Variola virus.
When the Europeans travelled to America, they transmitted a virus which was foreign to the Native Americans. Why was this virus so significant? This virus caused a disease called small pox; a lethal disease that killed thousands of Native Americans and ultimately helped the Europeans colonise America.
What is the Variola virus? The Variola virus is a pathogen which is a member of the genus Orthopoxvirus. The dumbbell shaped core contains the double stranded DNA. Surface tubules are found on the outside of the outer envelope. These surface tubules attach to the host cell’s membrane receptors allowing the virus to bind onto the host cell. How did this dangerous virus spread to the Native Americans from the Europeans? Small pox is an extremely contagious disease. The Variola virus can be easily transmitted when an infected person sneezes or coughs. Contaminated clothing and contact with smallpox scabs can also spread the Variola virus.
We now know how the Variola virus can be transmitted. But how do these microscopic particles drastically take over the body?
To begin with, the Variola virus attaches to the host cell and the host cell takes in the virus. The DNA of the Variola virus is then released into the cell, and these will start to replicate. Subsequently, the new strands of DNA are taken in by the developing spherical viral particles; as a result these particles will mature. Most of these mature viral particles will remain inside the host cell as intracellular mature viruses. Intracellular mature viruses are released from the host cell when the cell breaks down. The intracellular mature viruses can enter new host cells inside the infected person’s body, by fusing with the cell membrane. This is how the Variola virus infected the Native Americans and caused smallpox. Small pox has frightening array of symptoms. The initial symptoms of smallpox are headaches, high fevers and muscle aches. Shortly after, the Variola virus activity in the skin cells will cause pustules to develop across the skin. Haemorrhagic smallpox can cause fatality because this type of smallpox causes excessive bleeding of the skin, mucous membrane and the gastrointestinal track. To conclude, thousands of Native Americans died because they were exposed to a new virus (the Variola virus), when the Europeans travelled to America. Europe didn’t colonise America because of their clever political tactics or military strategies - it was due to a minute particle and its devastating effects on the Native American population.
The NCS (Newham Collegiate Sixth Form Centre)
My name is Sadiyah Zaman and I wrote this article because I have a passion for health care and I'm fascinated by diseases, the human anatomy and medicine.