Hemorrhagic fever South American

**Geographical South American Fever**:

South American geographic fever or hemorrhagic typhus (HST) is an acute febrile infectious disease caused by hantaviruses and manifested by erythema migrans syndrome. This disease is endemic in South America, where it has been known for many decades and is widespread among Indian tribes. In developed countries, hemorrhagic typhus is rare, most often as a result of importation of the disease from endemic regions or by persons from South America and Africa. The infection is transmitted to humans through the bites of mosquitoes belonging to the family of blood-sucking larvae.

Hantaviruses are closely related in size and protein structure to the Eastern chronic tick-borne encephalitis virus (TCEV). However, these two viruses are clearly differentiated by a set of characteristics - the composition of viral antigens, the characteristics of their interaction with cells, sensitivity to chemical and biological influences, etc.

In terms of morphological and qualitative characteristics, the hantavirus antigenic community is much more complex than that of TBEV. Moreover, it is not identical

South American hemorrhagic fever is a serious infectious disease that can lead to severe complications and even death. This disease is caused by a virus called RLFV - Rhabdo-Like Fever Virus. It is transmitted through blood or other body fluids, such as insect bites or contaminated water. However, in addition to this channel of transmission of infection, the disease is also transmitted through contact through touching a contaminated surface or objects, as well as through airborne droplets from a sick person when he coughs or sneezes.

Symptoms of South American hemorrhagic fever include high body temperature, headache, muscle aches, weakness, loss of appetite, diarrhea, vomiting, bleeding from the nose or mouth, abdominal pain and allergic reactions to insect bites. In more severe forms of the disease, there may be problems with blood clotting, bleeding problems such as internal rupture of blood vessels that can lead to bleeding, and disruption of vital functions.

South American hemorrhagic fever

South American hemorrhagic fever is an acute zoonotic viral disease from the group of hemorrhagic fevers, characterized by damage to small vessels and manifested by hemorrhagic syndrome against the background of hyperthermia. The causative agent of the disease is the Coxsackie virus, family Togaviridae

The virus has a spherical shape with a size of about 70–80 nm. Contains single-stranded RNA surrounded by a layer of protein. Virions are covered with a lipid supercapsid.

The reservoir and source of the pathogen are sick people, virus carriers and domestic animals. Infection occurs through mucous membranes or skin, as well as through inhalation of inoculated droplets of infected saliva. After invasion, the Coxsackie virus multiplies in the cells of the reticuloendothelial system, where its largest amount accumulates. From damaged macrophages, the virus enters the blood, spreads throughout the body and is released with the contents of the gastrointestinal tract.

After the end of the infectious process, lifelong post-infectious antibodies remain as a result of recovery. They do not provide immunity against re-infection with the virus, but may have a preventive effect upon contact with the pathogen.

The incubation period is from 3 to 7 days (in rare cases, it lasts up to 21 days). The disease is accompanied by chills and fever. Symptoms of infection with coronavirus and influenza are often similar, but with the hemorrhagic type of the disease, exanthematous hemorrhages are observed on the mucous membranes of the cheeks, tongue, gums, tonsils, and lips. Lesions are accompanied by vomiting, diarrhea, and sometimes nosebleeds are observed. A general blood test reveals a decrease in hemoglobin and platelets, leukocytosis, and accelerated ESR. Complications of South American hemorrhagic fever spread to the kidneys, spleen, and meninges. The most favorable prognosis is for young people; for older patients, the likelihood of death is much higher. The disease is rarely completely cured.