How did the once rampant trachoma disappear? The whole world should thank this Chinese man

Because the human body's constant body temperature provides reliable "living" conditions for many pathogens, many terrible infectious diseases have appeared in human history, and even the driving force behind human migration around the world are these infectious diseases.

At the beginning of the founding of New China, due to the explosive population growth and limited sanitary conditions, which provided good conditions for the spread of infectious diseases, many of the oldest and most terrible infectious diseases in human history began to wreak havoc, including trachoma, one of the most common blinding eye diseases in humans.

It is believed that the incidence rate in rural areas with poor sanitary conditions at that time could reach over 90%, and even in Shanghai with good sanitary conditions, the incidence rate of trachoma was about 50%, so there was a saying at that time that "nine out of ten people have trachoma."

The group most susceptible to trachoma is children. In my memory, when I was a child, as long as my eyes were slightly red and swollen, my family would be horrified and think that I had trachoma.

I remember that many people at that time believed that trachoma could be transmitted through eye contact, so people with red and swollen eyes would be regarded as aliens and no one dared to look them in the eye; what’s more interesting is that everyone also believed that plucking eyelashes could cure trachoma, so as soon as their eyes turned red, they would pull out their eyelashes frantically.

Trachoma has left a deep impression on generations. In 2014, China announced that it had met the World Health Organization's requirements for eradicating blinding trachoma. In March of this year, the World Health Organization confirmed that China had eliminated trachoma.

So, what kind of disease is trachoma, and how did China successfully eliminate trachoma?

Trachoma, source: Flickr

Trachoma: One of the oldest infectious diseases in human history

Although trachoma has been completely eliminated in China, it is still wreaking havoc around the world. Currently, at least 157 million people still live in trachoma risk areas, most of which are in African countries.

Approximately 1.9 million people are still blind or have reduced vision due to trachoma. Overall, trachoma remains one of the leading causes of blindness worldwide.

In fact, trachoma is one of the oldest known infectious diseases in humans. The oldest case of trachoma discovered by scientists can be traced back to 10,000 years ago. The eye bones of an Australian Aboriginal showed obvious sequelae of trachoma.

Trachoma patients will have blisters inside their eyelids, and their eyes will feel uncomfortable as if sand has entered them. This may be the origin of the name "trachoma".

Once a person gets trachoma, it is basically difficult to heal on his own. Trachoma will accompany the patient throughout his life, causing pain to the patient's eyes all the time, and will not stop until the patient becomes completely insomniac.

In the early stages of infection, the eyes will have a stronger reaction, the eyes will be congested and accompanied by secretions, and will be very painful and itchy.

However, the symptoms will be alleviated after the acute symptoms because scar tissue is formed. Many people may think that they are cured, but in fact they have just entered a chronic scarring process. In the scarring process, some permanent damage will occur, the most obvious of which is entropion. The cause of blindness caused by trachoma is entropion, which causes the eyelashes to scrape the cornea and eventually damage the cornea - this is an irreversible blindness process.

The average person needs to blink more than 15,000 times a day. For trachoma patients, every blink is very painful and wears out their cornea.

Perhaps it is because trachoma patients' eyelashes often scrape the cornea and cause pain, so many of us believe that plucking eyelashes can cure trachoma (I have seen such claims in other countries as well). After all, having no eyelashes can indeed alleviate this pain.

In fact, in addition to plucking out eyelashes, there are many strange "folk remedies" for trachoma. In some areas of China, doctors will even put a knife into the eyes to scrape off the trachoma follicles in an attempt to treat trachoma (it's scary to think about it).

The reason for these strange trachoma treatments was simple: people at the time had no idea what caused trachoma.

The first person to isolate the trachoma pathogen was a Chinese scientist, Tang Feifan. He accomplished this feat under extremely harsh scientific research conditions, which was truly remarkable at the time.

Photo: Tang Feifan

Trachoma pathogen

At the beginning of the 20th century, the scientific community was actually very eager for quick success and instant benefits, because the world at that time was like a "Panther's Box" that had just been opened, with many subversive facts waiting to be discovered.

Many researchers are afraid that their hard-earned research projects will be published by others first, so they publish papers directly without sufficient data, which leads to many mistakes.

There are many people researching a global disease like trachoma and the competition is very fierce. At that time, a Japanese researcher, Hideyo Noguchi, announced that his team had isolated the trachoma pathogen without much factual support.

Picture: Tang Feifan is the third from the right in the front row

Tang Feifan felt that Noguchi Hideyo's method was not capable of obtaining the trachoma pathogen. After returning to China in the spring of 1929, the first thing he did was to isolate the trachoma pathogen according to Noguchi Hideyo's method.

Then, he experimented on monkeys with the isolated "pathogen", and the monkeys still showed no symptoms of trachoma after 7 months, so he concluded that the Japanese scientists' method was not capable of isolating the trachoma pathogen.

However, China's scientific research capabilities were not recognized by the world at that time, and the denial of Japanese scientists' approach immediately pushed Tang Feifan to the forefront.

Even though he encountered a lot of criticism in the scientific community and the situation in China was very unstable at the time, none of these stopped Tang Feifan from stopping his research on trachoma pathogens.

It was not until 1955, after seven failures, that Tang Feifan and his team finally successfully isolated a "virus" (thought to be a virus at the time) in the eighth experiment and named it TE8.

Figure: Chlamydia trachomatis

Now we know that the pathogen of trachoma is neither a virus nor a bacterium, but Chlamydia. If a trachoma patient glares at you, the Chlamydia will not fly into other people's eyes, and plucking eyelashes cannot remove the Chlamydia.

Chlamydia is a prokaryotic organism like bacteria, but unlike bacteria it cannot synthesize ATP on its own. All energy for its life processes is provided by the host cells.

On the other hand, the size and survival mode of Chlamydia are more like viruses, but compared to viruses, Chlamydia has two nucleic acids, DNA and RNA, and a membrane similar to a cell wall.

Because chlamydia is more like bacteria in structure, the disease was easy to treat when antibiotics were already widely available, and it could be cured using broad-spectrum antibiotics.

In addition, after knowing the causative factors of trachoma, the plan to block the spread of trachoma becomes very obvious. Just wash your hands frequently, rub your eyes less, and use separate hygiene products such as towels.

Therefore, in the following years, the incidence of trachoma dropped significantly. By the 21st century, trachoma had basically disappeared from China.

at last

In fact, after Tang Feifan questioned the Japanese scientists, many scientific teams in the world have been committed to finding new methods to isolate trachoma pathogens, but all to no avail.

Tang Feifan was the first scientist to isolate Chlamydia, so he is recognized worldwide as the "Father of Chlamydia".

In fact, after obtaining Chlamydia trachomatis, he also conducted experiments on his own eyes to obtain the most valuable clinical data.

In addition, as one of the earliest microbial researchers in China, Tang Feifan's achievements go far beyond Chlamydia trachomatis. He is also the "Father of Vaccines" in China.

We mentioned earlier that the first thing he did after returning to China in 1929 was to start research on trachoma, but it was not until 1955 that he obtained Chlamydia trachomatis. In fact, during this period of time, he also successfully isolated penicillin and the cowpox vaccine, both of which were the first in China.

Under the promotion of Tang Feifan, New China's epidemic prevention "equipment" went from nothing to having the vital penicillin and various vaccines, making terrible diseases such as smallpox, measles, rabies and so on disappear in China ahead of schedule.

Source: Weird Luo