The human history has witnessed a host of deadly and extremely contagious disease outbreaks that devastated humankind. For example, the plague pandemic has eradicated even a whole city in the history. Other devastating outbreaks, such as smallpox, severe acute respiratory syndrome (SARS) and human immunodeficiency virus (HIV) have caused great public panic and severe death toll.
Nevertheless, during the process of our fighting against these diseases, our understanding toward them has improved dramatically. Some of these conditions have already been eradicated (e.g., smallpox) by vaccines and some can be successfully treated and controlled (e.g., HIV) now.
So it is reasonably expected that these once prevalent and intimidating monsters would be finally cured or even completely eradicated.
Smallpox is thought to be present on the planet in the 3rd century BC, based on the findings of smallpox-like rash found on Egyptian mummies. Before the 15th century, smallpox was confined to the Eurasian landmass. However, the Western colonists introduced this disease to America, Africa and Australia.
Smallpox devastated the native Americans with a fatality rate over 90%. In 1796, Sir Edward Jenner developed a technique of using cowpox to protect vulnerable people from smallpox. With the development of smallpox vaccines, it was possible to protect massive people. Smallpox was officially declared to be eradicated by WHO in 1977.
Researchers believe that HIV originated in the Congo in around 1920 when HIV passed across species from chimpanzees to humans. In fact, people knew little about this condition between 1920-1980. In the 1980s, increasing cases of immune deficiency noted in gay or those who used illicit drugs were reported, so the initial name of HIV was “gay-related immune deficiency.”
People gradually recognized that this condition was caused by a virus that predominantly targets the CD4+ T cells, a critical component of your immune system that helps you to fight against infections. This virus is predominantly transmitted through unprotected sexual behaviors and/or unsafe needle or syringe use. The prognosis was very poor in the early years when this virus was detected.
However, with deeper understanding of HIV biology and virology, antiviral drugs started to be developed. In the late 1990s, “highly active antiretroviral therapy (HAAT)” was applied, which dramatically improved patients’ life expectancy.
Although HIV cannot be cured, it can be treated and controlled. For example, the life expectancy for a 20-year-old HIV patient before HAAT was invented was about 39 years, and it increased to 70 years in the 2010s.
The first case of SARS was first reported in Guangdong Province, China in 2002 as “atypical pneumonia (literally meaning pneumonia that is not typical). This disease spread to 4 continents (Asia, Europe, North America and South America). This condition was later demonstrated to be caused by a new strain of coronavirus, with which the coronavirus COVID-19 shared some similarities. This condition was transmitted through respiratory droplets from patients’ sneezes or coughs. This disease claimed 774 deaths in total, among 8,098 confirmed cases.
Through all these contagious diseases introduced above, you can see that people are improving in treating diseases, even severe ones. With the medical technology today, we can control the COVID-19 with efficient measures.