General characteristics of the disease
Yellow fever is an acute hemorrhagic (accompanied by hemorrhage) disease has a viral etiology.
The source of infection with the virus are wild animals, usually possums and monkeys, as well as the sick people it. Carriers of yellow fever mosquitoes are, while directly from person-to-person virus is not transmitted. This disease is endemic in Latin America and tropical areas of Africa.
It is estimated that in the world every year the virus affects about 200 thousand. People for 30 th. Of which outcome is fatal in nature. Over the past twenty years there has been a trend of increasing cases of infection with yellow fever, which is caused by low immunity of the population, urbanization, deforestation, migration and climate change.
The most effective prevention of the disease today is a vaccination against yellow fever.
Yellow fever virus in the incubation period is about 3-6 days, after which the infection begins to emerge.
The disease may have one or two stages. For the first stage characterized by fever, chills, back pain, muscle aches, headache, loss of appetite, vomiting or nausea.
For most patients the disease is limited to this stage - after 3-4 days the symptoms of yellow fever are. However, in 15% of cases a day after remission of patients awaiting a second stage, the more toxic than the previous one. At this stage, the body temperature rises again, there is a loss of body systems, rapidly begins to develop jaundice, a patient suffering from vomiting and abdominal pain.
Characteristic symptoms of yellow fever at this stage are bleeding from the nose, mouth and eyes. Perhaps the bleeding from the stomach, which is manifested in the form of blood in the feces and vomiting. Furthermore, at this stage of the disease is worsening renal function. About 50% of patients faced with toxic stage of the disease die within 10-14 days, and in most cases the rest recover without significant organ damage. Only occasionally are the possible complications of the disease in the form of pneumonia, myocarditis, gangrene limb or soft tissue. It is also possible the development of sepsis caused by secondary bacterial flora.
The symptoms of yellow fever are similar to the symptoms of severe malaria, leptospirosis, viral hepatitis, and other hemorrhagic fevers, poisoning, so to diagnose the disease is very difficult. Identify the yellow fever virus can only be qualified health workers by conducting laboratory tests or blood samples taken postmortem liver tissue.
Treatment of yellow fever
Specific treatments for yellow fever to date have not been developed, so can only be symptomatic treatment of the disease.
Patients are encouraged to comply with bed rest and observe gentle diet rich in high-calorie foods. Treatment of yellow fever involves massive vitamin therapy, the use of non-steroidal anti-inflammatory drugs (except acetylsalicylic acid) infusion administration of plasma expanders and absorbent products. When expressed bleeding can be assigned to a blood transfusion.
Prevention of disease
Vaccination against yellow fever is the most important and effective way of preventing the disease. Vaccination is necessary not only living in endemic areas, but also those traveling to the edge of the tourists.
The certificate of vaccination against yellow fever is necessary for all persons traveling to Africa or Latin America. If for medical reasons a traveler, vaccination is contraindicated, an exemption must be certified by the competent authorities.
Yellow fever vaccine containing attenuated virus allows for a week in 95% of vaccinees develop a reliable immunity to the disease, which persists for 30-35 years and sometimes for life. Despite the fact that the vaccine is recognized as one of the most highly effective and safe in the history of vaccinology, a yellow fever vaccination and contraindications. This vaccine is not intended for:
- children younger than 9 months in the case of routine immunization;
- children younger than 6 months if the epidemic;
- pregnant women - are the exception to the outbreak;
- persons with severe allergy to egg protein;
- individuals with severe immunodeficiency caused symptomatic HIV / AIDS or other causes, or suffer from diseases of the thymus gland.
An infected person, even in the mild form of yellow fever is a danger to others, so in order to prevent further spread of the virus, the patient provides maximum protection from mosquito bites. Isolation of the patient is suitable only for the first 4 days later because he is no longer a source of infection for mosquitoes.
Non-specific way to prevent yellow fever is a mosquito control, including the destruction of breeding these insects, insecticide spraying to destroy adult, as well as the addition of these chemicals in water sources where mosquitoes are beginning to develop.