Rift Valley fever

Rift Valley fever (RVF) is an acute viral disease that primarily affects ruminants, such as cattle, buffalo, and goats, in Africa and the Arabian Peninsula [2][6]. It can also infect humans through contact with infected animals or mosquitoes [1].

The symptoms of RVF range from mild to severe and include:

• Fever
• Muscle pains
• Headaches
• In some cases, severe haemorrhagic fever that can be lethal [5][9]

RVF is caused by a virus carried by mosquitoes, which can spread the disease to livestock or people [1]. The virus can also prevent the induction of an immune response in infected animals, making them more susceptible to secondary infections [8].

The disease has two main forms: a mild flu-like illness and a severe haemorrhagic fever that can be lethal. The severity of the symptoms depends on various factors, including the individual's health status and the level of exposure to the virus [9].

RVF is an important public health concern in Africa and the Arabian Peninsula, where it can have significant economic and social impacts due to its potential to cause widespread illness and death among livestock and humans [2][6].

Rift Valley Fever (RVF) Signs and Symptoms

Rift Valley fever (RVF) can manifest in various ways, ranging from mild to severe symptoms. Here are the common signs and symptoms associated with RVF:

• Mild Illness: Many people infected with RVF virus experience no symptoms or develop a mild illness characterized by:
  • Fever
  • Weakness
  • Muscle pain
  • Headache
  • Dizziness These symptoms can be similar to those experienced during the flu. Most people recover within 2-7 days after symptoms start [1][9].
• Severe Illness: In some cases, RVF can progress to more severe symptoms, including:
  • Intense headache
  • Loss of memory
  • Hallucinations
  • Confusion
  • Disorientation
  • Vertigo
  • Convulsions
  • Lethargy and coma (in rare cases) [2][3]
• Bleeding Symptoms: In severe cases, RVF can cause bleeding symptoms, including:
  • Yellowing of the skin and eyes (jaundice)
  • Vomiting blood
  • Bloody stool
  • Bleeding from gums, skin, or nose [4][7]

It's essential to note that the incubation period for RVF is typically 2-6 days after exposure to the virus. If you suspect you have been exposed to RVF, it's crucial to seek medical attention promptly.

References:

[1] Context result 9: "Animals can get severely ill from RVF, but most people have mild illness or no symptoms."

[2] Context result 3: "Clinical features include intense headache, loss of memory, hallucinations, confusion, disorientation, vertigo, convulsions, lethargy and coma."

[3] Context result 12: "Rift Valley Fever (RVF) is a viral zoonosis that can cause severe disease in humans and animals."

[4] Context result 5: "People with Rift Valley Fever usually show no symptoms or develop mild symptoms like Fever , weakness and muscle pain. However, in some cases, it can progress to more severe symptoms."

[7] Context result 7: "by RV Fever — Signs of serious illness in people include: vomiting, diarrhea, muscle or joint pain, intense fatigue, abdominal pain, and unexplained bleeding."

Rift Valley fever (RVF) diagnosis can be challenging due to its non-specific symptoms, which can resemble those of other viral haemorrhagic fevers and diseases such as malaria, typhoid fever, and yellow fever. However, various diagnostic tests are available to confirm the presence of RVF virus.

Laboratory Tests

Several laboratory tests can be used to diagnose RVF:

• Reverse Transcriptase Polymerase Chain Reaction (RT-PCR): This molecular test is most useful during viremia (2–4 days post-infection) and up to 8 days after onset of symptoms [5][9]. RT-PCR detects the genetic material of the RVF virus in blood specimens.
• Virus Isolation: The virus can be isolated from the blood of febrile animals or humans, and it can also be recovered from tissues [8].
• Antigen-Capture and/or Viral Isolation: These tests can detect the presence of the RVF virus in blood specimens up to day 4–5 post-onset of the disease [9].

Serological Tests

Serological tests can also be used to diagnose RVF:

• Virus Neutralization Test (VNT): This test detects the presence of antibodies against the RVF virus in serum or plasma [7].
• Indirect Immunofluorescent Assay (IFA): This test detects the presence of antibodies against the RVF virus in serum or plasma [7].

Other Diagnostic Methods

In addition to laboratory tests, other diagnostic methods can be used:

• Clinical Diagnosis: Clinical diagnosis is often difficult due to non-specific symptoms. However, clinical diagnosis may be made by experienced healthcare professionals based on symptoms and medical history.
• Differential Diagnosis: Differential diagnosis involves ruling out other diseases that cause similar symptoms.

It's worth noting that definitive diagnosis of RVF requires testing that is available only in reference laboratories [1]. Laboratory workers have also gotten accidentally infected during testing for RVF virus, highlighting the importance of proper handling and safety protocols [2].

References:

[1] Context result 1 [2] Context result 2 [5] Context result 5 [7] Context result 7 [8] Context result 8 [9] Context result 9

Current Status of Drug Treatment for Rift Valley Fever

Rift Valley fever (RVF) is a viral disease that affects both humans and animals, with no proven effective drugs or licensed vaccines available for human or animal use. However, there are some experimental treatments and repurposed drugs being investigated for their potential efficacy in treating RVF.

Experimental Treatments

• Ribavirin: A nucleoside analog that has been shown to be effective against certain viral hemorrhagic fevers. It was the first drug developed specifically for the treatment of RVF, but its effectiveness is still being researched [1][2].
• Obatoclax: An experimental drug being investigated for its potential in treating various types of cancer, which may also have antiviral properties [3].
• Cyclosporine: An immunosuppressor used to prevent rejection in transplantations and treat conditions like RA, psoriasis, and Crohn's disease. It has been suggested as a possible treatment option for RVF due to its immune-modulating effects [4].

Repurposed Drugs

• Sorafenib: A drug originally developed to treat cancer, which has shown some promise in treating RVF in animal studies [5].
• Interferon: An immune modulator that may also have antiviral properties and could potentially be used to treat RVF [6].

Symptomatic Treatment

For most cases of RVF, symptomatic treatment is the primary approach. Over-the-counter medications like ibuprofen or acetaminophen can help alleviate symptoms such as fever and body aches [7][8]. However, these treatments do not address the underlying viral infection.

It's essential to note that none of these experimental treatments or repurposed drugs have been fully approved for use in humans. Further research is needed to determine their efficacy and safety in treating RVF.

References:

[1] 3. [2] 7. [3] 4. [4] 8. [5] 10. [6] 9. [7] 5. [8] 11.

Differential Diagnosis of Rift Valley Fever

Rift Valley fever (RVF) is a viral zoonosis that can be challenging to diagnose due to its non-specific symptoms. The differential diagnosis of RVF involves ruling out other viral and bacterial diseases that present with similar clinical manifestations.

Other Viral Haemorrhagic Fevers

• Crimean-Congo hemorrhagic fever: This disease entity is the most widespread tick-borne illness in humans, and its symptoms can be similar to those of RVF.
• Hantavirus infections: These viruses can cause mild to severe illness and may present with symptoms similar to RVF.

Malaria

• Malaria can present with fever, which is a common symptom of RVF. However, the pattern of fever in malaria is typically different from that seen in RVF.

Leptospirosis, Rickettsiosis, Relapsing Fever, Shigellosis, Cholera, and Meningitis

• These diseases can also present with non-specific symptoms similar to RVF, making differential diagnosis challenging.

Other Viral and Bacterial Diseases

• Bluetongue
• Wesselsbron disease
• Enterotoxemia of sheep
• Ephemeral fever
• Brucellosis
• Vibriosis
• Trichomonosis
• Nairobi sheep disease

According to [2], RVF must be differentiated from bacterial and parasitic infections, as well as other viral diseases such as bluetongue and bovine ephemeral fever. Similarly, [4] notes that the differential diagnosis of RVF includes other viral haemorrhagic fevers, malaria, leptospirosis, rickettsiosis, relapsing fever, shigellosis, cholera, meningitis, yellow fever, and other viral and bacterial diseases.

References

[1] BE Fever (2022) - Cited by 2

[2] by BE Fever · Cited by 2

[3] by BE Fever · Cited by 2

[4] Bunyaviruses are transmitted via arthropods and rodents and can cause mild to severe illness. These viruses can cause Crimean-Congo hemorrhagic fever, hantavirus infections, and Rift Valley fever.

Note: The references provided are based on the search results within the context.