Rift Valley Fever is an infectious, viral disease of sheep, cattle and humans that occurs mainly in East Africa. Rift Valley fever belongs to the group of hemorrhagic fever. How is Rift Valley Fever caught and treated?

Virus causingRift valley feverwas first isolated in 1931 from sheep in the Rift Valley in Kenya. The Rift virus has also been isolated from nearly 30 species of mosquitoes and flies. It is insects that transmit it to pets. Some scholars believe that there is no evidence that the infection was transmitted by food, despite the fact that the virus was isolated from an experimentally infected cow. Transmission of the virus to humans is possible by inhalation through inhalation of air containing blood particles of sick animals (veterinarians, slaughterhouse workers, laboratory staff). The infection can also be transmitted to humans through the bites of mosquitoes and bloodsucking flies. A sick person can be a threat to pets as mosquitoes and flies will transmit the virus from person to animal.

Contents:

  • Rift Valley Fever: Symptoms
  • Rift valley fever: recognition
  • Rift Valley Fever: Treatment
  • Rift Valley Fever: Prevention
  • Rift Valley Fever: Epidemics

Rift Valley Fever: Symptoms

The incubation period for Rift Valley fever is 2 to 6 days (some sources say 4 to 6 days). This disease occurs in many clinical forms:

  • asymptomatic,
  • flu-like infection - features: rapid temperature rise, general weakness, muscle aches and headaches, dizziness and a long recovery period,
  • hard.

Three syndromes are distinguished among the severe forms of the disease:

  • Ophthalmic syndrome- occurs in 0.5-2% of patients. The patient has visual disturbances, ecchymosis in the retina and macular edema. The most common complication of this form of the disease is viral damage to the retina, including the macula. There is also a frequent loss of central vision.
  • Encephalomyelitis syndrome- occurs in less than 1% of patients. Meningeal symptoms begin 5 to 15 days after the feverish period. For 1% of people infected with this formdiseases end in death; this mainly applies to people who are malnourished, debilitated by other diseases or are inadequately treated,
  • Hemorrhagic fever syndrome- develops in about 1% of patients. After a few days of fever, there is jaundice, bloody vomiting and tarry stools, bleeding gums and petechiae, or ecchymosis. These are small red, brown or purple spots, about 3 mm in diameter, caused by extravasation of blood from capillaries to the skin or mucous membranes. The lesions usually appear in groups and may resemble a rash.) Necrotic foci in the liver are found on necropsy. The mortality rate in this team is high, reaching even 50%.

Rift valley fever: recognition

The ELISA test is especially useful as it can detect IgM antibodies. The rt-PCR reaction also makes it possible to diagnose the disease at an early stage in animals and humans.

The diagnosis of Rift Valley fever in animals can also be based on a histopathological examination of a specimen from the liver. Pathognomonic changes occur in the diseased liver - the presence of necrosis and eosinophilic intranuclear inclusions.

Rift Valley Fever: Treatment

When the disease is not complicated, it is usually sufficient to treat the symptoms. In severe cases, intravenous administration of ribavirin may be warranted and has been shown to be effective in mice, cats and monkeys. The administration of immunized plasma and interferon therapy are also considered beneficial.

Rift Valley Fever: Prevention

Prevention of Rift Valley fever is to limit contact with sick animals and their excretions. You must protect yourself from mosquito and fly bites by wearing long-sleeved and leg-worn clothing and using insect repellent. When traveling to Africa, we do not go barefoot in places where there may be domestic animal excrement. People working in the handling of animals or in slaughterhouses, as well as in laboratories must follow safety rules. Although there is insufficient evidence of oral transmission, it is advisable to avoid food that is not cooked. This also applies to milk and foods containing meat or blood from sick animals.

Vaccination of animals is an important element in the prevention of Rift Valley fever. Such vaccinations are not carried out in Poland.

Rift Valley Fever: Epidemics

An epizootic has occurred on several occasions at irregular intervals since 1931, when the virus was isolated from sheep in the Rift Valley in Kenya(plague, plague), i.e. the animal equivalent of an epidemic among people. The most serious was the episode in South Africa in the summer of 1950-1951, during which around 100,000 people died. heads of sheep and cattle, and also recorded 20 thousand. In the years 1974-1976 another significant increase was observed in domestic animals and people in this area.

Until 1977, the disease was confined to countries south of the Sahara. In 2000, the disease spread beyond Africa. Her cases have been described, among others. in Yemen (over a thousand suspected disease, 121 deaths) and in Saudi Arabia (882 confirmed cases, 124 deaths).

Outbreaks of Rift Valley fever typically occur during the rainy season, as the carrier insects multiply rapidly under these conditions.

Anna Jarosz A journalist who has been involved in popularizing he alth education for over 40 years. Winner of many competitions for journalists dealing with medicine and he alth. She received, among others The "Golden OTIS" Trust Award in the "Media and He alth" category, St. Kamil awarded on the occasion of the World Day of the Sick, twice the "Crystal Pen" in the national competition for journalists promoting he alth, and many awards and distinctions in competitions for the "Medical Journalist of the Year" organized by the Polish Association of Journalists for He alth.

Category:

Infectious diseases