Ebola

Ebola and Marburg

• Ebola and Marburg are severe zoonotic multisystem febrile diseases caused by RNA viruses. They are notifiable diseases.

• Morphology : The Ebola virus is filamentous, often resembling a “U” or “S” shape. It measures approximately 2 μm (micrometers) in length and 70-80 nm (nanometers) in diameter. It has an internal structure (nucleoprotein core) enclosed within an external envelope studded with numerous glycoprotein spikes.
• Multiplication : The virus replicates by budding from its internal structures.

Types of Ebola Viruses:

Ebola Virus (EBOV) : This is the species most commonly associated with severe outbreaks in humans.

• EBO-Zaire (EBO-Z) : This subtype has a high fatality rate, averaging around 89%.
• EBO-Sudan (EBO-S) : This subtype has a fatality rate of 41.65%, although this can vary depending on factors like treatment and location.

Vectors :

• Mosquitoes and Termites : While there have been theories suggesting these insects could play a role in transmission, there is no definitive evidence to support their role as vectors for Ebola.
• Bats : The most likely primary reservoir for Ebola viruses. They can harbor the virus without showing symptoms and transmit it to other animals or humans.
• Dogs : While some sources mention dogs, there is no clear evidence to suggest they are a significant reservoir for Ebola.

Human-to-Human :

• Direct contact with infected bodily fluids, such as blood, vomit, feces, urine, and saliva.
• Contact with contaminated materials like clothing, bedding, needles, and medical equipment.
• Sexual contact with a survivor who is still shedding the virus in semen (this can last for months after recovery).

Animal-to-Human : Contact with infected animals (particularly primates like chimpanzees and gorillas) or their bodily fluids.

Mosquitoes : As mentioned above, mosquitoes are not considered reliable vectors for Ebola virus transmission.

The Ebola virus affects multiple tissues throughout the body, not just a specific organ. It causes widespread damage, including:

• Necrotic Lesions: The virus leads to cell death (necrosis) in various organs, affecting their functionality.
• Immune System Suppression: Ebola weakens the immune system, making individuals vulnerable to other infections.

Incubation Period:

• Primary Infection: The incubation period typically ranges from 2 to 21 days after exposure.
• Secondary Infection: For transmission from human to human, the incubation period is the same, 2 to 21 days.

Causes :

Ebola Virus : The causative agent is the Ebola virus, a member of the Filoviridae family. There are five known species of Ebola virus:

• Zaire ebolavirus (responsible for the most severe outbreaks)
• Sudan ebolavirus
• Reston ebolavirus (not known to cause disease in humans)
• Taï Forest ebolavirus
• Bundibugyo ebolavirus

Marburg : Marburg virus

• Communities Around Game Parks: Proximity to wildlife increases the risk of exposure.
• Endemic Areas : Regions with a history of EVD outbreaks.
• Cultural Practices: Burial rituals involving close contact with the deceased can facilitate transmission.
• Poor Infection Control : Inadequate sanitation and hygiene practices in healthcare settings can increase the spread.
• History of Exposure: Contact with infected individuals within 2-21 days prior to symptom onset (e.g., sexual partners, breastfeeding mothers).
• Contact with Infected Animals : Handling infected animals (like monkeys, bats, and infected game meat).

Early Signs (Non-Specific):

• Sudden Feve r: A rapid onset of high fever (often exceeding 101.5 °F / 38.6 °C).
• Weakness : General feeling of weakness and exhaustion.
• Headache : Intense headache.
• Muscle Pain : Pain in muscles and joints.
• Loss of Appetite : Decreased appetite or inability to eat.
• Conjunctivitis : Inflammation of the conjunctiva (white part of the eye).

Late Signs :

• Diarrhea : Profuse diarrhea, sometimes with blood.
• Vomiting : Severe vomiting.
• Mucosal and Gastrointestinal Bleeding : Bleeding from the nose, gums, eyes, and rectum.
• Chest Pain : Pain in the chest area.
• Respiratory Distress : Difficulty breathing.
• Circulatory Shock: Low blood pressure and impaired blood flow.
• CNS Dysfunction: Confusion, seizures, and coma.
• Miscarriage in Pregnancy : EVD can cause miscarriage or stillbirth in pregnant women.
• Elevated AST and ALT: Elevated levels of liver enzymes, indicating liver damage.
• Kidney Injury : Damage to the kidneys, potentially leading to kidney failure.
• Electrolyte Abnormalities : Imbalances in electrolytes (minerals like potassium and sodium) in the body.

Other clinical presentations include;

• Sudden Onset : Symptoms usually appear abruptly.
• Severe Headache : Intense headache is a common initial symptom.
• Myalgia and Fever: Muscle pain (myalgia) and high fever (often exceeding 38.5 °C).
• Conjunctival Inflammation : Inflammation of the conjunctiva (white part of the eye).
• Gingival Bleeding : Bleeding from the gums.
• Sore Throat: Sore throat with associated chest pain.
• Abdominal Pain: Pain in the abdomen.
• Nausea, Vomiting, and Diarrhea : These symptoms are prominent features of EVD, with diarrhea often being profuse and watery.
• Signs of Dehydration : Dehydration can develop due to fluid loss from vomiting and diarrhea.
• Severe Bleeding : Internal and external bleeding may occur from the gastrointestinal tract, gums, nose, and other orifices. This typically develops between the 5th and 7th days.
• Morbiliform Rash : A rash similar to measles may appear on the 7th day.
• Neurological Manifestations: Neurological complications such as psychosis and hemiplegia (weakness or paralysis on one side of the body) can occur.
• Death : Death often occurs around the 9th day, but can happen between the 2nd and 21st days.

Note: Hemorrhage is not always a prominent feature of EVD. It’s important to remember that EVD symptoms can vary significantly.

• Malaria : A parasitic disease that also causes fever, headache, and muscle aches.
• Meningitis : Inflammation of the membranes surrounding the brain and spinal cord.
• Shigellosis : A bacterial infection causing diarrhea, abdominal cramps, and fever.
• Typhoid Fever : A bacterial infection causing high fever, headache, and constipation.
• Anthrax : A bacterial infection causing skin lesions, fever, and respiratory problems.
• Sepsis : A serious bacterial infection causing fever, chills, and rapid heart rate.
• Viral Hepatitis : Inflammation of the liver caused by viruses like hepatitis A, B, or C.
• Dengue Fever : A viral infection transmitted by mosquitoes, causing fever, headache, and muscle pain.

Blood Sample for Specific Testing : Blood samples from suspected EVD cases should be collected by trained healthcare professionals wearing proper PPE.

• Laboratory Testing : The blood sample needs to be sent to a reference laboratory for specific tests to identify the Ebola virus.
• Real-Time PCR: This is the preferred method for detecting Ebola virus.
• Antigen and Antibody Detection : ELISA (enzyme-linked immunosorbent assay) and other antibody tests can identify Ebola virus antigens and antibodies.

Postmortem : If an individual dies from EVD, postmortem examination is critical for confirmation and to prevent further spread.

Notification : Immediately notify the district surveillance focal person if you suspect a case of EVD.

Management Aims:

• Fluid Replacement: Maintain adequate hydration to compensate for fluid loss.
• Prevention of Spread : Isolate the patient and implement strict infection control measures.
• Conservation of Energy : Provide rest and supportive care to conserve energy.
• Symptom Relief: Administer medications to manage symptoms like fever, pain, and vomiting.

Specific Management:

1. Admission : Admit the patient to an isolated room in a medical ward, providing complete bed rest.

• Bed Preparation: Use a freshly prepared bed, with a comfortable position for the patient (supine or semi-recumbent depending on their condition).

2. Protection :

• Handwashing : Strict handwashing before and after attending to the patient.
• Isolation : Isolate the patient in a designated room, and implement barrier nursing techniques. Healthcare workers and patient attendants should wear gowns, gloves, goggles, and gumboots to prevent contact with bodily fluids.
• Identification Tag: Place an “INFECTIOUS” tag on the door to alert others about the infectious nature of the room.

3. Fluid Replacement: Administer intravenous fluids (N/S, RL, and Dextrose 5%) according to the doctor’s prescription.

4. Hygiene :

• Patient Hygiene : Maintain cleanliness of the patient’s skin, secretions, and stool. Disinfect with bleach solutions before disposal.
• Bed Pans : Scrub bed pans thoroughly with strong detergent, rinse, and dry.
• Patient’s Orifices: Wash and dry the patient’s orifices. Apply perineal pads if needed for profuse diarrhea.
• Linens : Disinfect linens in a bleach solution for at least 6 hours. Label and transport them in “infected linen” bags to be sluiced, boiled, dried, and ironed.
• Room Disinfection : Mop the room, scrub the floors and walls, disinfect lockers, and wash and boil patient utensils for at least 10 minutes.
• Refuse Disposal : Place food and hospital refuse in polythene bags and incinerate.

5. Diet : Provide a fluid diet in the acute stage, primarily through IV fluids and oral fluids as much as possible.

6. Terminal Disinfection : Thoroughly disinfect the room and all contaminated materials after the patient is discharged.

7. Notification : Report the case to health authorities to inform the public health system about the outbreak.

Health Education:

• Patient Attendants : Educate patient attendants about the infection, its mode of transmission, and prevention measures.
• General Public : Inform the general public about the disease, its signs and symptoms, and preventative measures.
• Patient Care: Ensure the patient feels supported and understood, preventing isolation and stigma.

• Avoid Contact: Minimize contact with the patient’s blood and secretions.
• Personal Protective Equipment: Wear proper PPE (gowns, gloves, masks, eye protection) when providing care.
• Safe Burial Practices: Use safe burial practices to prevent transmission during funerals.
• Vaccination : The Ebola vaccine is available and should be considered for high-risk individuals.
• Isolation : Isolate infected individuals in designated Ebola treatment centers.
• Contact Tracing : Identify and monitor individuals who have come into contact with infected persons.

• Shock : Monitor for signs of shock (low blood pressure, rapid heart rate, weakness, and cool, clammy skin).
• Organ Failure : Monitor for signs of organ failure (e.g., jaundice for liver failure, decreased urine output for kidney failure).
• Disseminated Intravascular Coagulation (DIC): Be aware of the signs of DIC (bleeding from multiple sites, bruising, and difficulty controlling bleeding).
• Meningitis : Monitor for signs of meningitis (stiff neck, headache, fever).
• Encephalitis : Monitor for signs of encephalitis (confusion, seizures).
• Secondary Infections : Monitor for signs of secondary infections (fever, cough, difficulty breathing).
• Psychological Trauma : Provide psychological support to patients and their families to address potential psychological trauma.