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A list of infectious diseases that are the easiest to contract has been compiled
Last reviewed: 01.07.2025
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As long as pathogens live in nature, we will get sick, supporting the existence of infection. It is a kind of vicious circle. Among all the microorganisms capable of causing disease, there are those that are characterized by particularly high contagiousness. This is the ability of pathogens to infect people, causing disease.
The most worrisome diseases are influenza, tuberculosis, and measles. But beware of other contagious diseases, too.
1. Hepatitis A
As is known, the causative agent of the disease is a virus, the target of which is the liver. Failure to comply with sanitary and hygienic standards helps the disease to penetrate the body. The virus is transmitted with poorly washed hands, vegetables, fruits, and also when drinking untreated water. The disease manifests itself in a number of symptoms: fatigue, fever, abdominal pain, nausea, diarrhea, loss of appetite and jaundice.
Europeans, Americans and residents of other so-called "highly developed" countries practice vaccination against hepatitis A. Artificial immunity lasts for 15 years. As for the rest, they should remember the basic rules of hygiene to avoid getting sick.
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2. Malaria
This disease, known since ancient times, takes more than one million lives annually. The pathogen is carried by a mosquito of the genus Anopheles. Through its bite, the malaria plasmodium enters the human blood and attacks red blood cells, destroying them. Characteristic manifestations of malaria are fever, chills, nausea, anemia and convulsions. Without treatment, the prognosis for life is very disappointing.
It is easiest to become infected with malaria in tropical and subtropical latitudes, and generally anywhere where there are conditions for the reproduction of the carrier - the malaria mosquito. Today, the main problem of treatment has become the resistance of the pathogen to antimalarial drugs.
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3. Measles
Many people become familiar with this disease in childhood. And all because of the very high contagiousness of the measles virus.
The pathogen is known to be transmitted by airborne droplets with an efficiency of 90%. That is, 90% of those who come into contact with a patient with measles and are not vaccinated against the pathogen will fall ill. The disease manifests itself in the form of fever, catarrhal symptoms of the respiratory tract (runny nose, cough), through conjunctivitis and a rash on the skin and mucous membranes characteristic of measles. Dangerous complications of measles are pneumonia and encephalitis.
If you decide to get natural immunity, go to kindergarten - there is the highest probability of catching this disease. Actually, it is better to get measles in childhood - adults have a hard time with the disease. The only good thing is that the immune memory remains for life.
4. Tuberculosis
Every second someone encounters the tuberculosis pathogen; in general, a third of people in the world are infected. Meeting with the infection does not necessarily entail development into disease. By the way, the transmission route can be both airborne and alimentary (with food).
Symptoms of the most common form of tuberculosis - pulmonary consumption - in the early stages may include fatigue, weight loss, fever, loss of appetite, and cough.
The problem of tuberculosis is most acute in developing countries. In Ukraine, an epidemic of this disease has been declared since 1995. Control over the incidence of tuberculosis is achieved through BCG vaccination.
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5. Flu
Who doesn't know this insidious virus? Just recently, in the last century, millions of people died from the "Spanish flu" (according to some estimates, about 40 million between 1918 and 1920). It was the largest pandemic in history.
The flu virus is an RNA virus, it mutates easily, and this causes new strains to emerge. That is why we get the flu more than once in our lives, because we are infected with a different strain of flu each time.
The virus is transmitted by airborne droplets. It is easier to prevent the disease if you refrain from contact with sick people and do not visit crowded places during seasonal outbreaks of infection.