Infectious diseases are still one of the most common causes of death worldwide. The causes, symptoms, treatment measures and consequences differ in a wide range of infectious diseases. Prevention is not possible in all cases.
What are infectious diseases?
Infectious diseases are contagious diseases caused by microorganisms and usually associated with fever. The pathogens usually transmitted from person to person are viruses, bacteria, parasites, fungi or prions.
However, it is also possible to transfer animals to humans. In addition, there are other infections that do not originate from living creatures. Infectious diseases are predominantly infected with viruses and bacterial infections. The infection is caused by contact, coughing or exhalation as well as by a smearing of body juices such as saliva, blood, sperm or pus.
The pathogens enter the body via the digestive tract, skin, mucous membranes or airways. The typical disease symptoms are only recognizable after a certain incubation period. Many infectious diseases usually heal after a certain time without medical treatment. Some infectious diseases have a high risk of infection and contamination and require
medical assistance. In order to combat certain infectious diseases, there is a legal obligation to report these diseases to health authorities. They are to take measures to prevent the spreading of the disease. These include disinfection, isolation, warnings and vaccination. After an infectious disease, there is often an immunity which prevents a repetition of the same disease.
The causes of infectious diseases are manifold. The development and transmission of the pathogens can be influenced by the personal immune system, by the effectiveness of a vaccination, by the hygienic conditions or by the environmental stress. The pathogens, which are responsible for an infection, are in each case in an infection source before transmission.
Living organisms that act as sources of infection are referred to as hosts. In animals, transgenes of pathogens are mainly pigs, rats, chickens, and cattle. In addition, birds, ticks or mosquitoes can also trigger infectious diseases. However, the cause of an infection may also be, for example, contaminated water.
Even over the air, transmissions of pathogens such as chickenpox or measles are possible. Likewise, spoiled foods can cause an infection. This can be done by bacteria such as salmonella disease and by viruses such as noroviruses. In the soil or dust, there may be exciters for tuberculosis.
Fungi can cause infections of the skin as well as the mucous membranes. In a weakened immune system, organs can also be attacked. Infectious diseases such as AIDS can be transmitted sexually. Bacterial infections in the area of the sexual organs are possible due to an insufficient genital hygiene.
Bacteria and parasites are often the cause of infectious diseases with diarrhea. Pulmonary infections can be caused by bacteria or by viruses. At the winter time, a flu virus is often transmitted by droplet infection by coughing and sneezing.
Symptoms and history
Typical symptoms of infectious diseases:
- Joint pain
- a headache
- difficulties swallowing
The characteristic symptoms of the infectious disease are usually fever, swelling, redness due to inflammation, pain or itching. In addition, defensive reactions of the irritated organs occur, such as a cough, hoarseness, runny nose, cramps or nausea.
The strength of the symptoms is also dependent on the condition of the personal immune system and the age of life. In the case of viral infections and bacterial infections, the symptoms may be diarrhea, increased the urge to urinate, discolouration of urine, swallowing difficulties, headache and limb pain.
In addition, it can also be caused by chills, rash, itching as well as difficulty breathing or fatigue. In some cases, it is difficult to detect the symptoms of infection in good time. This may, for example, be problematic in the development of a borreliosis.
Frequently, in this disease, the specific symptoms are either completely absent or are only difficult to assign. Some infectious diseases occur only in certain regions of the body, others affect the whole body.