Yellow fever

Historians of medicine differ in the definition of the oldest source, in which it is a question of yellow fever ^[3] . Some are inclined to consider as such a 1598 record of the deaths of the warriors of George Clifford, Earl of Cumberland , on the island of Puerto Rico , from "tropical fever" ^[4] . However, this record could also be about malaria , which in those days was also called “tropical fever” and the epidemics of which also flared up during the “rainy season”. Therefore, they usually count on the description of the epidemic on the Yucatan Peninsula in 1648 .

At that time, the population of Central America and the islands of the Caribbean region suffered from severe, recurring epidemics , and it was then that the British doctors suggested the name of the disease, yellow fever, on the island of Barbados . The Spaniards used the name "black vomit" ( isp. Vomito negro ). Among the English sailors and soldiers who were the most painful for her, the name Yellow Jack was in circulation ^[3] .

On August 14, 1881, at a public meeting of the Havana Academy of Sciences, Cuban physician Carlos H. Finlay set out his hypothesis that yellow fever is transmitted by a certain type of mosquitoes .

Two decades later, fighting the yellow fever epidemic in Havana in 1900, Walter Reed and James Carroll confirmed that the yellow fever was transmitted by the bite of the Aedes aegypti mosquito, and the detachment led by William Crawford Gorgas eliminated all the mosquito breeding centers of the mosquitoes. there was not a single case of yellow fever - for the first time in two hundred years ^[5] .

In 1915, after the success of William Crawford Gorgas in Havana and Panama, the Rockefeller Foundation launched an action to eradicate yellow fever in the Western Hemisphere ^[6] and, indeed, urban centers of yellow fever were practically eliminated in North and South America. But in 1928, a severe epidemic broke out again in Rio de Janeiro , followed by epidemics in other cities in central South America. The investigation into the origins of these epidemics led to the discovery of forest foci and the realization that yellow fever existed in America even before Columbus ^[3] .

In 1937, the American virologist Max Teiler created a vaccine against yellow fever, for which he was awarded the Nobel Prize in Physiology and Medicine in 1951.

A female mosquito sucking the patient's blood with yellow fever becomes infectious after 4 days at 30 ° C and 20 days at 23 ° C ^[7] .

Yellow fever exists in two epidemiological forms: jungle fever (transmitted by mosquitoes from infected monkeys) and village fever (transmitted by the Aedes aegypti mosquito from a sick person to a healthy person). The latter causes the majority of outbreaks and epidemics ^[8] .

Each year, yellow fever affects about 200 thousand people, of which 30 thousand die ^[9] . About 90% of all cases are diagnosed in Africa ^[10] .

The causative agent is the arbovirus Viscerophilus tropicus from the flavivirus family. The diameter of the virus particles - 17-25 nm. Able for a long time (more than a year) to remain frozen and during drying. The virus quickly dies when heated to 60 ° C, under the influence of ultraviolet rays, ether, chlorine-containing drugs and when exposed to conventional disinfectants.

The incubation period ranges from 3 to 6 days, occasionally up to 10 days.

The clinical picture of the disease is characterized by a biphasic course.

The course of the disease varies in severity from mild fever to severe hepatitis with hemorrhagic fever. Severe flow is characterized by a sudden onset, accompanied by fever up to 39–41 ° C, chills, severe headache, pain in the muscles of the back and limbs, nausea, and vomiting. The patient's appearance is typical: icteric staining of the skin due to liver damage (hence the name of the disease); face red, puffy, eyelids swollen. After a short light period, shock can occur, hemorrhagic syndrome with the development of acute renal failure, acute hepatic failure develops. When the disease develops at lightning speed, the patient dies in 3-4 days.

Mortality of the disease ranges from 5-10% to 15-20%, and during epidemic outbreaks - up to 50-60%.

Specific drugs for the treatment of yellow fever does not exist. Assistance is reduced to symptomatic treatment, including rest, infusion solutions , painkillers. Non-steroidal anti-inflammatory drugs ( acetylsalicylic acid , naproxen , ibuprofen , etc.) should be avoided, which may increase the risk of bleeding ^[11] .

Vaccination of people traveling to endemic areas. The vaccine contains a weakened (attenuated) virus strain 17D ^[12] . Yellow fever vaccine is considered one of the safest and most effective vaccines in vaccine history ^{[13] [14]} . Reliable immunity develops within one week in 95% of the vaccinated and lasts for 30–35 years (possibly for life) ^[15] . Currently, in many countries revaccination is performed every 10 years.

Vaccine is contraindicated:

• children under the age of 9 months with regular immunization (or up to 6 months during the epidemic);
• pregnant women - with the exception of yellow fever outbreaks, when the risk of infection is high;
• persons with severe egg white allergy;
• persons with severe immunodeficiency as a result of symptomatic HIV / AIDS or other causes, or in the presence of diseases of the thymus gland.

The patient is a source of infection, even in light forms of the disease and must be completely protected from mosquito bites. To this end, around the bed set grid, metal or gauze. Such isolation of the patient is necessary during the first 4 days, since after this period he is no longer a source of mosquito infection.

Non-specific prophylaxis includes the prevention of mosquito bites and disinsection of nearby water bodies .

A list of countries endemic for yellow fever is available on the CDC website.

A list of countries requiring an international certificate of yellow fever vaccination.

• 1. Benin
• 2. Burkina Faso
• 3. Gabon
• 4. Ghana
• 5. Democratic Republic of Congo
• 6. Cameroon
• 7. Congo
• 8. Costa Rica
• 9. Côte d'Ivoire
• 10. Liberia
• 11. Mauritania
• 12. Mali
• 13. Niger
• 14. Peru (only when visiting jungle areas)
• 15. Rwanda
• 16. Sao Tome and Principe
• 17. Togo
• 18. French Guiana
• 19. Central African Republic
• 20. Bolivia

The list of countries with endemic areas for this infection, upon entry to which it is recommended to have an international certificate of vaccination against yellow fever:

South American countries

• 1. Venezuela
• 2. Bolivia
• 3. Brazil
• 4. Guyana
• 5. Colombia
• 6. Panama
• 7. Suriname
• 8. Ecuador

African countries

• 1. Angola
• 2. Burundi
• 3. The Gambia
• 4. Guinea
• 5. Guinea-Bissau
• 6. Zambia
• 7. Kenya
• 8. Nigeria
• 9. Senegal
• 10. Somalia
• 11. Sudan
• 12. Sierra Leone
• 13. Tanzania
• 14. Uganda
• 15. Chad
• 16. Equatorial Guinea
• 17. Ethiopia

International initiatives

At the initiative of the World Health Organization (WHO), preventive vaccination against yellow fever is carried out. The initiative is supported by UNICEF and includes regular immunization of children from 9 months of age, as well as mass vaccination campaigns in high-risk areas for all age groups 9 months and older, epidemiological surveillance and outbreak response ^[15] .

Vaccination, storage and distribution of vaccines are carried out by the International Coordinating Group (ICH) for the provision of yellow fever vaccines. The group was created at the initiative of WHO, it also includes Doctors Without Borders , the , and the United Nations Children's Fund (UNICEF). The ICG maintains an emergency reserve of yellow fever vaccines to ensure rapid outbreak response in high-risk countries ^{[16] [17]} .

The WHO Expert Council at regular meetings approves the list of manufacturers whose vaccines are officially used to combat yellow fever. This list includes ^[18] :

• Institut Pasteur de Dakar (Senegal) (status: active)
• Sanofi Pasteur (France) (status: active)
• Bio-Manguinhos / Fiocruz (Brazil) (status: suspended)
• FSBI "FNTSIRIP named after MP Chumakov of the Russian Academy of Sciences" (Russia) ^[19] (status: temporarily suspended)

• Epidemics of yellow fever in Buenos Aires

• on the CDC website
• on the Russian-language website of WHO
• Yellow Fever (Febris flava) Herald of Infectology and Parasitology
• Yellow fever // Brockhaus and Efron Encyclopedic Dictionary : 86 tons (82 tons and 4 extras). - SPb. , 1890-1907.