The most terrible diseases of all time

Many people think that plague, leprosy and polio . are diseases of the past, no longer affecting us, it is a wrong thought.

The influenza A / H1N1 virus of the years 1918-1919 caused millions of people to die now still in existence, threatening our lives.

Recently in China, people had to quarantine a town within 10 days after discovering 3 people with plague died. This is one of the signs that the disease has never disappeared from the ground.

' There are many diseases that we rarely mention but are very difficult to eradicate, ' said Dr. DA Henderson, the first person to work with the World Health Organization (WHO) to eliminate the virus.

' There are many infectious diseases that still exist with us forever, ' said Dr. Peter Hotez, professor and chairman of the Department of Microbiology and Immunology at George Washington University.

' Most of these diseases are more common in rural areas than in urban areas, ' Dr. Hotez said. ' Where there is poverty, there is no doubt that there will be these pathogens in existence .'

Dangerous diseases come from the past but today still exist in the human world

1. Bubonic plague

People with plague and bacteria cause plague.(Photo: ABC News)

The plague was born by a bacterium called Yersinia pestis , which can be spread from person to person. Plague bacteria are usually found in wild mice and fleas, when they get close to humans, fleas will spread germs to humans more easily than mice.

The disease can be treated with antibiotics but cannot be eliminated.

' Yersinia pestis bacteria are in the wild, ' says Howard Markel, a pediatrician and a medical historian at the University of Michigan. ' It still exists on the body of fleas and rat family, and no one knows how to kill all the fleas and mice in the world, so this disease has, is and will remain '.

2. H1N1 swine flu

The outbreak of a disease called Spanish influenza A in the winter of 1918-1919 caused thousands of thousands of deaths. This is probably the pandemic that caused the most deaths. And almost a century has passed, we still cannot eliminate them. Currently, according to the latest statistics from WHO, the number of deaths caused by influenza A / H1N1 is 1,462 people.

The 1918 flu pandemic claimed tens of millions of lives

Certainly the number of people dying from this disease will continue to increase. And although there are different names for type A flu from the 1918s, they all share the same basic structure, H1N1. This type of virulent virus has changed and survived even though people have tried their best to curb their development.

' We cannot know the exact location of these viruses, ' said Dr. Patricia Winokur, a professor at the University of Iowa who is studying vaccines against swine flu. ' They lie dormant somewhere that we cannot know, then enter the human world .'

Influenza viruses have changed over time, changing every year and destroying the human immune system.

"Every year, they just change a bit," says Ms. Winokur. "And the proteins change a bit and the immune system is no longer as perfect as it was, no longer able to resist the invasion of the micro." this bacterium '.

She also added that scientists have also developed a vaccine to help prevent influenza and flu prevention to reduce infection but not very effective. ' Every year it changes a bit to adapt and survive, to continue to harm people.'

Flu viruses exist in birds and pigs so 'it is very difficult to eradicate this disease ', Ms. Winokur said. ' We cannot vaccinate all birds and all pigs as vaccines against human smallpox'.

3. Polio

Like smallpox, polio also has vaccines , so many people think it can make it go away forever.

' WHO has a campaign to eliminate the disease in the belief that it could be eliminated like smallpox,' Hotez said. But the truth is that polio has a number of different characteristics from smallpox and cannot be eliminated.

Polio can cause paralysis on the body or even paralysis.

But he added that ' only 1 out of 100 people have germs that develop into paralysis. Many people will have no symptoms' .

In order to prevent the spread of smallpox, people injected with people living around the patient a specialized vaccine. But polio is not so, this disease has no clear signs, so it is difficult to determine who has the germ. Therefore, this disease is very unpredictable.

4. Diseases of the drill bit

(Photo: ABC News)

' Bacterial nose disease is an infection caused by parasites. It is a disease of the poor, 'said Dr. Carlos Franco-Paredes, a specialist in the treatment of infectious diseases at Atlanta hospital. Parasites of this disease reproduce on insects, live in dilapidated houses, attack people at night.

When being attacked by a virus that attacks the drill, people will be sad, irritable and it can be spread from person to person when the infected person scratches the skin and the skin is in contact with others.

Hotez estimates in Latin America, the number of people infected with this disease is 8-9 million people and in the US, this number is 400,000 people. It is also transmitted through blood transfusions . And a study conducted by Franco-Paredes in 2006 showed that in some fruits and sugarcane in South America, there exists a type of bacteria that has been drilled.

The bacteria will gradually attack the heart or develop symptoms of liver pain or spleen swelling. But up to 95% of infected people show no signs within 20 to 30 years.

' If the disease is already in a complicated stage, the bacteria have entered the heart, there is no treatment, ' he said.

' The only treatment is heart transplantation ,' he said, but when the disease progresses to the end, it cannot be cured. ' It is necessary to discover it early ,' Hotez said.

This is called a disease that reflects ' social inequality ', Hotez said: ' If there is no redistribution of rich and poor in Latin American countries, then we will not be able to reduce this disease '.

These are diseases that have existed in the past, still exist today, harming human life.

5. Leprosy

Leprosy bacteria erode hands(Photo: ABC News)

This is one of the oldest diseases in the human world caused by Hansen bacteria . Because there are no spores, the bacteria are not transmitted through intermediate hosts. When outside, it only lasts 1 to 2 days.

The disease attacks the skin and nerve cells on the body. Flesh of infected people often boils, sores. When more severe, the wound is concave in the skin, the eyebrows fall, the eyes are exposed, the larynx is sore so the voice is hoarse.

When nerves in some parts of the body become infected, the skin appears to have a loss of sensation. After that, the muscles that go away, the tendons shrink, make the hands twitch. At the level of heavy fingers, the toes fell gradually .

'The disease is curable, but to this day, we do not know how leprosy is spread ,' said Franco-Paredes.

' There is no evidence that this disease spreads from person to person, ' he added.

' We now have good and widespread treatments ,' said Franco-Paredes. ' But leprosy will continue to exist in the human world until we know its spread. I'm sure that in the next few centuries, we will still face leprosy . '

6. Hookworms

Hookworm (Photo: ABC News)

In the early twentieth century, hookworm disease spread in rural areas of South America with a very high rate. Lack of nutrients and parasitic infections have caused this epidemic, and it not only exists in South America but also in many other poor areas of the world.

Hookworm eggs follow the soil, having favorable conditions in terms of temperature, humidity and soil will hatch into larvae, living in soil for weeks. Meet people, larvae crawl through the skin, often in the instep, interstitial toe, causing red, itchy rashes, sometimes with inflamed succulent nodules. This symptom lasts 3-4 days and then goes away.

The larvae pass through the skin into the lymph and blood, then into the lungs, enter the alveoli, move to the bronchi and throat and then swallow into the small intestine. When larvae enter the lungs, patients often have mild fever or when fever is not.

Hookworm parasites attack people, causing anemia . Hotez has studied a vaccine to treat hookworm but need to invent a better kind.

7. Tuberculosis

(Photo: ABC News)

' It is difficult to eradicate tuberculosis and so far, it is still living with humans . before history is written, ' said Douglas Hornick, PhD, who studies tuberculosis-related problems at the University. Iowa said.

' This is a disease that develops silently, the bacteria attack so slowly that the patient only coughs for a long time .' Severe symptoms are patients who can develop continuous fever, fatigue and rapid weight loss.

There are no specific signs to discover that someone has been infected with tuberculosis , so when a person does not know he or she has it, some others have been infected.

Currently, tuberculosis has become more complicated and a disaster because they are complicated, resistant to TB medicines.

' We can cure tuberculosis, but it is hard to cure cases of complications ,' Markel said. ' It is a serious disease, especially in cases where bacteria are resistant to many drugs. If this is the case, no medicine can be cured . '

In the United States, people often get skin scans to determine if they have TB infection but this method has not been implemented in other countries around the world, even in countries with high rates of TB infection.

Scientists estimate that about one-third of the world's population is infected with TB.

" 80-90% of people with this virus do not know they are infected because TB has no specific symptoms, it is easy to identify ," Hornick said.

' I don't feel very optimistic. I think tuberculosis will remain with us forever, 'he said.