Most diseases do not appear just like that, but are transmitted from the source to a he althy person. We suggest that you familiarize yourself with the types of transmission of infections, as well as understand in more detail the vector-borne diseases. This is especially true in the warm season.
Types of transmission
Infection can be transmitted to humans in the following ways:
- Alimentary. The route of transmission is the digestive system. The infection enters the body with food and water containing pathogens (eg, intestinal infections, dysentery, salmonellosis, cholera).
- Airborne. The route of transmission is inhaled air or dust containing the pathogen.
- Contact. The route of transmission is the source of infection or disease (for example, a sick person). You can become infected by direct contact, sexual contact, as well as household contact, that is, through the use of common household items (for example, a towel or dishes) with an infected person.
- Blood:
- vertical, during which the mother's illness passes through the placenta to the baby;
- transmissible transmission of the disease - infection through the blood with the help of live carriers (insects);
- blood transfusion, when infection occurs through insufficiently processed instruments in the dental office, various medical institutions (hospitals, laboratories, and so on), beauty salons and hairdressers.
Transmissive transmission method
The transmissible way of transmission of infection is the entry of infected blood containing pathogens into the blood of a he althy person. It is carried out by live carriers. The transmission route involves the transmission of pathogens with the help of blood-sucking insects:
- directly at the bite of an insect;
- after rubbing against damaged (e.g. scratched) skin of a dead insect vector.
Without proper treatment, vector-borne diseases can be fatal.
Modes of transmission and vector classification of vector-borne diseases
Transmissible transmission of the disease occurs in the following ways:
- Inoculation - a he althy person becomes infected during an insect bite through his oral apparatus. This transmission will occur several times if the vector does not die (for example, this is how malaria spreads).
- Contamination - a person becomes infected by rubbing the feces of an insect into a bitten place. Infectioncan also be repeated many times, until the death of the carrier (an example of a disease is typhus).
- Specific contamination - infection of a he althy person occurs when an insect is rubbed into damaged skin (for example, when there are scratches or wounds on it). Transmission occurs once, as the carrier dies (an example of a disease is relapsing fever).
Carriers, in turn, are divided into the following types:
- Specific, in the body of which pathogens undergo development and have several stages of life.
- Mechanical, in whose body pathogens do not develop, but only accumulate over time.
Types of diseases that are transmissible
Possible infections and diseases transmitted by insects:
- relapsing fever;
- anthrax;
- tularemia;
- plague;
- encephalitis;
- human immunodeficiency virus;
- Chagas disease, or American trypanosomiasis;
- yellow fever (viral disease of the tropics);
- various types of fevers;
- Crimean-Congo hemorrhagic fever (high mortality rate - from ten to forty percent);
- dengue fever (typical of the tropics);
- lymphatic filariasis (typical of the tropics);
- river blindness, or onchocerciasis, and many other diseases.
There are about two hundred types of diseases that are transmissible.
Specific vectors for vector-borne diseases
We wrote above that there are two types of carriers. Consider those in whose organisms pathogens multiply or go through a development cycle.
| Blood-sucking insect | Disease |
| Female malarial mosquitoes (Anopheles) | Malaria, wuchereriosis, brugiasis |
| Mosquito Biters (Aedes) | Yellow fever and dengue, Japanese encephalitis, lymphocytic chorionmeningitis, wuchereriosis, brugiasis |
| Culex mosquitoes | Brugiasis, wuchereriosis, Japanese encephalitis |
| Mosquitoes | Leishmaniasis: cutaneous, mucocutaneous, visceral. Pappatachi Fever |
| Lice (clothes, head, pubic) | Rapid and relapsing fever, Volyn fever, American trypanosomiasis |
| Human fleas | Plague, tularemia |
| Bug | American trypanosomiasis |
| Bitches | Filariotosis |
| Mosquitoes | Onchocerciasis |
| Tse-tse fly | African trypanosomiasis |
| Gidflies | Loazosis |
| Ixodid ticks |
Fever: Omsk, Crimean, Marseille, Q fever. Encephalitis: tick-borne, taiga, Scottish. Tularemia |
| Argas mites | Q fever, relapsing fever, tularemia |
| Gamas mites | Rat fever, encephalitis, tularemia, Q fever |
| Red heifer ticks | Tsutsugamushi |
Mechanical vectors of vector-borne infections
These insects transmit the pathogen as received.
| Insect | Disease |
| Cockroaches, house flies | Helminth eggs, protozoan cysts, various viruses and bacteria (for example, causative agents of typhoid fever, dysentery, tuberculosis, and so on) |
| Autumn burner | Tularemia, anthrax |
| Bitches | Tularemia |
| Gidflies | Tularemia, anthrax, polio |
| Aedes mosquitoes | Tularemia |
| Mosquitoes | Tularemia, anthrax, leprosy |
Transmission of human immunodeficiency virus
The number of infecting units in onemilliliter of blood of an HIV-infected person - up to three thousand. This is three hundred times more than in seminal fluid. The human immunodeficiency virus is spread in the following ways:
- sexually;
- from pregnant or breastfeeding mother to child;
- through blood (injection drugs; during a transfusion of infected blood or transplantation of tissues and organs from an HIV-infected person);
Transmissible transmission of HIV infection is almost impossible.
Prevention of vector-borne infections
Preventive measures to prevent transmission of vector-borne infections:
- deratization, that is, the fight against rodents;
- disinsection, that is, a set of measures for the destruction of vectors;
- a set of procedures for improving the area (for example, melioration);
- use of individual or collective methods of protection against blood-sucking insects (for example, special bracelets soaked in aromatic oils, repellents, sprays, mosquito nets);
- immunization activities;
- placement of the sick and infected in a quarantine zone.
The main goal of preventive measures is to reduce the number of possible vectors. Only this can reduce the likelihood of contracting diseases such as relapsing fever, transmissible anthroponoses, phlebotomy fever and urban cutaneous leishmaniasis.
The scale of preventive work dependson the number of infected and characteristics of infections. So they can be held within:
- streets;
- district;
- cities;
- areas and the like.
The success of preventive measures depends on the thoroughness of the work and the level of examination of the source of infection. We wish you good he alth!
