Ebola Virus

Definition/Description

“Ebola virus disease (EVD) is a severe and often fatal zoonotic infection caused by viruses of the Filoviridae family (genus Ebolavirus)” [1]. Ebola virus disease is a hemorrhagic fever that is common in central and eastern Africa. The disease is caused by a single-stranded RNA flavivirus It tends to replicate on dendritic cells, macrophages and monocytes. The virus then uses multiple mechanisms to invade its host, including migration to the spleen, liver, and lymph nodes, resulting in widespread infection. [1] There are five known strains of Ebola virus disease: Ebola virus (formerly known as Zaire Ebola virus) Bundibugyo virus Sudan virus Tay Forest virus and Reston virus. Of the five strains, only Reston virus did not affect humans. Other strains have a fatality rate of between 30-90%, depending on the specific outbreak. [2]

EVD originates in animals and is transmitted to humans through hunting and eating bushmeat or exposure to bat droppings. Once humans become infected with Ebola virus disease, the virus spreads through contact with bodily fluids or reuse of needles that have not been properly decontaminated. [1] “Central Classification Disease control as a Category A agent has also designated EBOV as a bioterrorism threat, making this virus a priority for biodefense research” [3].

Source: www.youtube.com/watch

Prevalence

There have been 25 Ebola outbreaks since the first Ebola virus was identified in humans in 1976 [4]. The epidemic is mainly concentrated in West African countries, and there are also some outbreaks in the eastern and central regions. There have been more than 26,000 cases of the highly fatal virus Documented in West Africa [5]. “The Ebola virus disease (EVD) outbreak in West Africa has been described as one of the most devastating health crises of the 21st century. It has killed more than 11,000 people” [6]. The three largest outbreaks are in Sierra Leone and Guinea Liberia[5][7]. Available statistics for each outbreak are variable and may underestimate disease prevalence due to lack of healthcare reporting. Another contributing factor to this problem is lack of education. Recovering from the Civil War, the recession led to migration of the population to the cities. Overcrowding or migration to isolated rural communities and lack of transport to healthcare facilities. [6]

Source commons.wikimedia.org/wiki/File:EbolaSubmit2.png

This photo is used with permission from creativecommons.org/licenses/by-sa/3.0/deed.en

Source www.cdc.gov/vhf/ebola/outbreaks/history/chronology.html

Characteristics/Clinical Presentation

Ebola virus has the following signs and symptoms:

1. Early Stage

• abdominal pain
• anorexia
• arthralgia
• asthenia (extreme)
• back pain
• diarrhea
• fatigue
• fever (>37.5⁰C)
• headache
• myalgia
• sore throat
• vomiting

2. Mid Stage

• capillary leak
• confusion
• Dyspnea/respiratory distress
• headache
• low blood pressure
• nausea and vomiting
• rash (macropapular)

3. Late Stage

• delirium
• hemorrhage (external/internal)
• hiccups
• multi-organ failure
• shock (hypovolemic and septic)

Other symptoms of EVD although rare include encephalopathy hepatomegaly lymphadenopathy and seizures.[1][2][4][8]

Source:commons.wikimedia.org/wiki/File:Ebola_Symptoms_a.png

Licensed: creativecommons.org/publicdomain/zero/1.0/deed.en

Associated Co-morbidities

There are very few studies on the comorbidities seen in patients with Ebola. The most common co-morbidity seen in patients with Ebola is malaria. A study of epidemiologic clinical and outcome materials revealed that 72% of 90 patients with Ebola also developed malaria. Just one other one the comorbidity found in the study was diabetes mellitus (2% of the 90 patients).[9]

Medications

There is currently no licensed vaccine or treatment for the Ebola virus. But recent research has focused on experimental drugs and antiretroviral therapy and many other drugs are used to treat the many symptoms experienced by Ebola patients. The following are the current drugs and treatments against the Ebola virus:

1. Prevention and treatment of infections with antibiotics:[4][5]

• Cefixime
• Ceftriaxone
• Ertapenem
• Levofloxacin
• Meropenem
• Metronidazole
• Piperacillin-tazobactam
• Vancomycin

2. Antidiarrheal:[5]

• Diphenoxylate-atropine

3. Antifungal:[5]

• Micafungin

4. Rehydration:[4]

• Oral rehydration solution
• Ringer lactate

5. Sedative:[5]

• Propofol

6. Supportive care and analgesics for treatment of all symptoms:[1][4][5]

• Acetaminophen
• Diphenhydramine
• Electrolyte supplements
• Hydrocodone
• Meperidine
• Ondansetron
• Opioid analgesics (ex. morphine)
• Pantoprazole
• Paracetamol
• Phenazopyridine
• Protein-rich oral supplements
• Vitamins

The following are experimental drugs and therapies currently being tested by researchers for potential utility in the treatment of Ebola:

Emerging treatments:[1][2]

• ZMapp (best known emerging drug to date; experimental drug that has shown therapeutic benefit for Ebola in humans) .
• TKM-Ebola (proven to be protective in non-human primates and administered to a limited number of patients under emergency programs);
• Brincidofovir (shown activity against Ebola in vitro; administered to patients under emergency plan; future trials planned in west Africa)
• Favipiravir (effective against Ebola in mice; future human trials planned to start in West Africa)
• BCX-4430 (not yet studied in humans, but has shown activity against Ebola virus in nonhuman primates and rodents)
• AVI-7537 (increased survival in non-human primates infected with Ebola virus)
• Interferons amiodarone clomiphene and chloroquine (other agents under investigation with uncertain benefit against Ebola in humans) .
• cAd3-ZEBOV and rVSV-ZEBOV (two experimental vaccines currently undergoing human trials in the US) .
• Convalescent whole blood or plasma (limited evidence that blood transfusion may reduce mortality in convalescent patients but a pilot study is planned) .

Diagnostic Tests/Lab Tests/Lab Values

The gold standard for confirmation of Ebola is the reverse transcription polymerase chain reaction (RT-PCR)[4]. It can detect the virus in patients in the early and late stages of the disease. Another useful diagnostic test with high specificity but not universality available is antigen capture enzyme linked immunosorbent assay (ELISA)[1]. Laboratory tests that have been used for the molecular diagnosis of Ebola in addition to RT-PCR are the QIAGEN QIAamp Viral RNA Mini Kit and the MagMAX Pathogen RNA/DNA Kit (Life Technologies). Both of these methods used to purify RNA from whole blood. Tests for Ebola virus-specific antibodies (IgM and IgG) can also be performed to confirm the presence or absence of the disease.[5]

Laboratory test results that do not confirm the presence of Ebola virus but may be abnormal if an individual has the disease include: Elevated serum creatinine or urea levels Elevated serum glucose levels and elevated serum aspartate aminotransferase levels. Chest radiographs may also be performed in patients with respiratory symptoms. [1][5][10]

Etiology/Causes

Ebola virus disease (EVD) is primarily found in Africa, where it originated in some species of bats and primates such as gorillas and apes. Both hosts are known “hosts” of Ebola virus disease and both can be affected by the disease. Spread to humans in two ways: hunting and eating Bushmeat or eating food contaminated with bat droppings. Once a human is infected, Ebola virus disease is spread through contact with bodily fluids (blood, sweat, vomiting, diarrhea, saliva, feces, urine, genital secretions, and breast milk). Risk remains even if disease develops on its own due to viral shedding Spread through contact with semen, breast milk, saliva, feces, tears and possibly urine. Other transmission mechanisms include reuse of improperly sterilized needles and lack of clean water for handwashing. [1]

While this is the scientific explanation for Ebola, there are myths surrounding the disease and causing distrust among African people. The first myth is that a plane full of witches crashed and caused the first outbreak. The second myth is that a snake is released from a covered place An unsuspecting husband’s boxes and snakes continue to kill. [6] As such, there is a stigma surrounding the disease.

Source: www.cdc.gov/vhf/ebola/resources/virus-ecology.html

Systemic Involvement

Ebola virus can affect most systems throughout the body, including but not limited to:[1][4][11]

Cardiovascular System:

• Coagulopathy (increased fibrin degradation products, decreased clotting factors, and thrombocytopenia)
• sepsis
• tachycardia

Endocrine System:

• Adrenal insufficiency (impaired hormone secretion, leading to hypotension, hypovolemia, and renal sodium loss)
• pancreatitis

Gastrointestinal System:

• GI hemorrhage (lower and upper)
• hematemesis
• melena

Hepatic System:

• hepatitis
• hepatocellular lesions
• hepatocellular necrosis
• hepatomegaly
• liver damage

Immune System:

• lymphadenopathy
• systemic inflammatory response

Neurological System:

• aggression
• confusion
• hiccups
• metabolic encephalopathy
• neurotropism
• seizures

Ocular System:

• conjunctival infection
• uveitis

Renal System:

• acute kidney injury
• renal dysfunction

Medical Management

Medical management is a careful process of isolating symptom management and experimental drug therapy. Ebola has an incubation period of up to 21 days, during which time patients may be asymptomatic. There are three stages of Ebola with different symptoms. this The first stage is usually less symptomatic and may include headache, myalgias, and fever >37.5°C. The second stage includes various gastrointestinal symptoms such as nausea, vomiting, diarrhea and dehydration. The final stage is recovery or deterioration, including neurological changes Collapse and internal or external bleeding lead to death. [1]

Once a patient is suspected to have Ebola, he or she will be quarantined to prevent the spread of the virus. The patient is then tested for the presence of Ebola virus (see Diagnostic tests for more information). At the same time, anyone entering the patient Contact tracing over the past 21 days and a temperature reading BID is required to detect fever, which may indicate that the virus has spread. Normally, the virus does not spread until symptoms appear, but lack of medical facilities and Subtle early symptoms of EVD may not be noticed until days after symptoms appear. [1] “The most common symptoms reported between symptom onset and case detection in the 2014 outbreak were fever (87.1%) fatigue (76.4%) loss of appetite (64.5%) vomiting (67.6%) Diarrhea (65.6%) headache (53.4%) abdominal pain (44.3%) and unexplained bleeding (18%)” [1].

After the patient is isolated, a comprehensive medical screening will be performed to rule out other diseases and confirm the presence of Ebola virus. Screening includes, but is not limited to, temperature, blood pressure, pulse, respiratory rate, and physical examination. After patient visit Confirmed symptom management begins. Fluid and electrolyte supplementation is initiated to counteract dehydration from vomiting and diarrhea. Medications such as paracetamol and opioid pain relievers are given to counteract the initial side effects of fever and myalgia. Antiemetics Give orally or intravenously to reduce vomiting. In addition to these drugs, other drugs may be given as the virus progresses, depending on the symptoms the patient develops. There is no vaccine proven to prevent Ebola, but there are two A beta phase that may be open to the public in the future. Several emerging therapies have been developed to combat Ebola. Most were created during the recent Ebola outbreak. Because of the emergency, many treatments were not given Tests are done to see if they help or if there are any long-term side effects. [1] (See Diagnostic Tests and Medications for more information)

Source: www.youtube.com/watch

Physical Therapy Management

A very important aspect of physical therapy management associated with Ebola is the ability to recognize early signs and symptoms of disease and refer patients to physicians for treatment [1]. A key part of this is taking a deep dive into the patient’s medical history, paying special attention to Information about recent travel to areas where Ebola is endemic, or if the patient has been in contact with someone diagnosed with Ebola. Another factor that can aid in early identification is knowing the possible signs and symptoms of the virus (especially since These can be vague and nonspecific in the early stages of the disease) and the patient should be thoroughly examined [1]. Physiotherapists may also need to educate patients planning to travel to areas of Africa where Ebola is present about infection risk information. Exposure and Prevention. The best resource for individuals to obtain this information is the Centers for Disease Control and Prevention website: www.cdc.gov/vhf/ebola/

Another way that physical therapy management may be relevant to Ebola cases is in treating patients who have survived the virus and are recovering. Post-Ebola syndrome is present in nearly all survivors of the disease who report symptoms that persist or develop after an acute episode After illness and discharge from the hospital [4] 70% of patients experience musculoskeletal pain consisting of myalgia and arthralgia, which becomes a major health concern for these individuals [4][8]. Difficulty walking with unexplained pain in specific areas (such as knees, thighs, and back) Extensive musculoskeletal and joint pains have been reported as problems experienced by these patients affecting their function. Most musculoskeletal symptoms are currently treated with analgesics. [8] However, since physiotherapists specialize in treating musculoskeletal Condition and ability to restore and improve an individual’s function It stands to reason that Ebola survivors with post-Ebola syndrome would benefit greatly from physical therapy.

Differential Diagnosis

Ebola initially has many nonspecific symptoms, and once symptoms begin, they can resemble many different diseases. Some of these symptoms include fever, fatigue, nausea, vomiting, abdominal pain, diarrhea, rash, headache, muscle pain and general weakness. symptomatic disease Similar to what Ebola might be mistaken for:

Campylobacter and related infections [5]: www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/i-campylobacter-i-and-related-infections

Oki worm disease [5]: www.merckmanuals.com/professional/infectious-diseases/intestinal-protozoa/cryptosporidiosis

登革熱 [12]：www.merckmanuals.com/professional/infectious-diseases/arboviridae-arenaviridae-and-filoviridae/dengue

Giardiasis [5]: www.merckmanuals.com/professional/infectious-diseases/intestinal-protozoa/giardiasis

流感 [8]：www.merckmanuals.com/professional/infectious-diseases/respiratory-viruses/influenza

拉沙熱[6]：www.merckmanuals.com/professional/infectious-diseases/arboviridae-arenaviridae-and-filoviridae/lassa-fever

Malaria [5]: www.physio-pedia.com/Malaria

Septic shock [4]: www.merckmanuals.com/professional/critical-care-medicine/sepsis-and-septic-shock/sepsis-and-septic-shock

黃熱病 [6]：www.merckmanuals.com/professional/infectious-diseases/arboviridae-arenaviridae-and-filoviridae/yellow-fever

Source: www.cdc.gov/vhf/ebola/resources/infographics.html

Case Reports/ Case Studies

1. Kreuels B Wichmann D Emmerich P Schmidt-Chanasit J de Heer G Schmiedel S et al. A case of severe Ebola virus infection complicated by Gram-negative bacterial sepsis. New England Journal of Medicine 2014;371(25):2394-2401. Available from: CINAHL. [12]

www.nejm.org/doi/full/10.1056/NEJMoa1411677

2. Liddell A Davey R Mehta A Varkey J Kraft C Uyeki T et al. Characteristics and Clinical Outcomes of 3 Patients with Ebola Virus Infection Including First Domestic Acquisition in the United States. Annals Of Internal Medicine 2015;163(2):81-90. Available from: MEDLINE.[5]

annals.org/article.aspx

3. Lopaz M Amela C Ordobas M Dominguez-Berjon M Alvarez C Astray J et al. Second Ebola outbreak outside Africa: epidemiological characteristics and surveillance networks Spain September to November 2014. Euro Surveillance: Bulletin Européen Sur Les Maladies Transmissibles = European Infectious Disease Reports 2015;20(1). Available from: MEDLINE.

www.eurosurveillance.org/images/dynamic/EE/V20N01/art21003.pdf

4. Lyon G Mehta A Varkey J Brantly K Plyler L Ribner B et al. Treatment of two patients with Ebola virus infection in the United States. New England Journal of Medicine 2014;371(25):2402-2409. Available from: MEDLINE.[10]

www.nejm.org/doi/full/10.1056/NEJMoa1409838