When it comes to infectious diseases, perhaps the first thing that many people think of is pneumonia, influenza, and cholera. However, if you look back at the previous cases of infectious diseases, you will find that there are six major infectious diseases that make the world remember, namely smallpox, cholera, malaria, the Black Death, pneumonia and influenza.
Of course, these infectious diseases are different and have their own characteristics. First of all, let's talk about smallpox, this infectious disease has a very significant feature, that is, "delicious and lazy to do", to what extent is it "lazy"? In the thousands of years that it has survived, there has been no mutation, let alone an evolution.
According to records, smallpox, which evolved from rodent pox viruses more than 3,000 years ago, was first found in mummies. Once landed in India in the 6th century BC, it became a "hotbed" for the spread of smallpox due to the dense population of the region. There is even news that the demise of ancient Rome had a lot to do with smallpox.
Then smallpox landed in Eurasia, and what was everywhere on the streets of Europe at that time was that the faces of Europeans were not actually pimples, but had suffered from smallpox. The time of entry into China should be traced back to 1,000 years ago, reaching its peak during the Qing Dynasty. Eventually smallpox appeared on the American continent, so it also completed the circumnavigation of the world, and even Queen Elizabeth I of the United Kingdom and Washington, then the president of the United States, suffered from smallpox.
Eventually, after humans developed a vaccinia vaccine, the momentum of smallpox continued to spread was curbed. This is followed by malaria, a graded infectious disease that is said to have originated 500,000 years ago, but the real outbreak came at the end of the 19th century.
According to original records, malaria claimed nearly 100 million lives between 1900 and 1950. Then by 2015, malaria was spreading across 87 regions and countries around the world, infecting 200 million people in a year. Therefore, in the early days of the founding of New China, about 80% of the areas were infected with malaria.
In the end, tu youyou, a mainland scientist, developed artemisinin and successfully solved malaria. Next, let's talk about the famous cholera, an infectious disease that is very special. It is mainly transmitted in areas with poor sanitation conditions and can be transmitted through fecal mouths through drinking water contamination. It first appeared in 1817 and first in the Ganges Valley of India.
According to records at the time, the water of the Ganges was indeed sweet at first, and Indians often bathed in the water of the Ganges and drank the water of the Ganges. Unfortunately, as indians gradually destroyed the water quality of the Ganges, not only washing clothes in the river, but even taking out garbage, eventually making the river the most polluted. And with the outbreak of cholera in India, the death toll in the country reached 38 million. Cholera then made its influx in Europe, the Americas and Asia, and is now rarely seen.
Then there is viral pneumonia, the most intuitive manifestation of this pneumonia, which was originally SARS, and once entered Guangdong, China in 2002. Fortunately, after the national consensus and fight against SARS, it took about half a year to successfully curb the spread of SARS.
But another partner of pneumonia, which is still spreading around the world, does not know when it is a head. In addition, it is the Black Death, which can be said to have changed medieval Europe, although it was spread from 541 to 542 AD, only one year, but it caused 100 million people to die of the Black Death, and it appeared three times in total, and once landed in China.
Finally, there is the flu, which first appeared in Spain in 1918, and the rate of transmission was very fast, two years after the outbreak, directly caused 50 million to 100 million people to die from the flu, this data surpassed, the first world war human deaths.
Although a hundred years have passed so far, influenza still exists, such as the previous H1N1 flu and H7N9. It can also be argued that the flu has been accumulating strength and is ready to make a comeback. Therefore, it can be said that the above six major infectious diseases are enough to make the global human memory deep, and it is not known whether they will reappear in the future.