Causative agent, transmission, symptoms, pathogenesis, diagnosis, treatment, control

1. TRANSMISSION
Human-to-human transmission via direct contact
Sexual contact
Blood or body fluids of infected or dead person
Contaminated objects
Incubation: 3-14 days
EBOLA
SYMPTOMS
Incubation period: 2- 21 days.
A person infected with Ebola cannot spread the disease until they
develop symptoms.
Fever, fatigue, headache, Muscle and joint pain, abdominal pain,
malaise, sore throat, red eyes, conjunctivitis, weakness
Vomiting, diarrhea, rash
Complications
• Impaired kidney and liver function,
• Internal and external bleeding
• low white blood cell and platelet counts
• elevated liver enzymes.
• EVD is a rare but severe and often deadly disease.
• Recovery depends on good supportive clinical care and the
patient’s immune response.
• Survivors of Ebola virus infection have antibodies that can be
detected in the blood up to 10 years after recovery.
TREATMENT
• No specific medicine
• Take rest, drink plenty of fluids
• Blood products, immune therapies and drug therapies
• The rVSV-ZEBOV vaccine is being used in the ongoing 2018-2019 Ebola
outbreak in DRC.
CAUSATIVE AGENT
Ebola virus (Family:Filoviridae)
Affects humans and non human primates( monkeys,
chimpanzees and bats)
Morphologically similar to Marburg virus but
antigenically different.
Named after Ebola river in Sudan.
Three strains: Zaire strain; Fatality- 90%
Sudan strain ; Fatality- 50%
Mild Reston strain
DIAGNOSIS
• Antibody-capture enzyme-linked immunosorbent assay (ELISA)
• Antigen-capture detection tests, serum neutralization test
• Nucleic Acid Testing(NAT)
• Reverse transcriptase polymerase chain reaction (RT-PCR) assay
• Electron microscopy
• Virus isolation by cell culture.
CONTROL
Reducing the risk of wildlife-to-human transmission and human-to-human
transmission
PATHOGENESIS
• The virus enters through mucous membranes, breaks in the skin, or
parenterally and infects many cell types- monocytes, macrophages,
dendritic cells, endothelial cells, fibroblasts, hepatocytes, adrenal
cortical cells, and epithelial cells.
• The virus migrates from the initial infection site to regional lymph
nodes and subsequently to the liver, spleen, and adrenal gland.
• Lymphocytes undergo apoptosis resulting in decreased lymphocyte
counts. Hepatocellular necrosis and dysregulation of clotting factors
and subsequent coagulopathy.
• Adrenocortical necrosis associated with hypotension and impaired
steroid synthesis.
• Ebola virus appears to trigger a release of pro-inflammatory
cytokines with subsequent vascular leak and impairment of clotting
ultimately resulting in multiorgan failure and shock.
Ebolahemorrhagicfever