Ebola.pptx 1243

Ebola

Nabina shrestha Roll no. 3039

Introduction  Ebola virus disease, Ebola haemorrhagic fever commonly    

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termed Ebola. One of many haemorrhagic fevers. The disease takes its name as it was identified in a village near Ebola river in Congo, in 1976. Viral disease with an acute, serious illness which is often fatal if untreated. Caused by Ebola virus (Filoviridae/RNA virus) Fatality upto 90% in outbreaks.

Transmission  Fruit bats – natural Ebola virus hosts.

 Introduced into the human population through close

with the blood, secretions, organs or other bodily fluids of infected animals such as chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead.  Spreads through human-to-human transmission via direct (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and with surfaces and materials (e.g. bedding, clothing) contaminated with these fluids.

 People remain infectious as long as their blood contains the

virus.  Health care workers –frequently infected while treating patients with suspected or confirmed EVD.  Burial ceremonies in which mourners have direct with the body of deceased person play role in disease transmission.

Risk factors :  Close s of Infected individuals  Family  Care givers

 Health care personnel  People involved in managing dead bodies

Epidemiology  Ebola virus first appeared in 1976, causing simultaneous

epidemics of severe hemorrhagic fever (550 human cases) in Zaire and Sudan. Later confirmed as 2 different epidemics.  Epidemics - usually begins with single case acquired from an unknown reservoir in nature (fruit bats), and spread mainly through close with sick person or their body fluids, either at home or in the hospital.  Associated with inter human spread (particularly in the hospital setting) and the use of unsterilized needles and syringes.

 After an interval of apparent inactivity of almost 20 years,

the Zaire Ebola virus recurred in a major epidemic (317 cases) in the DRC in 1995 with high mortality rate – 88%.  Smaller epidemics in Gabon in 1994–1996. The epidemic smoldered, when intense nosocomial transmission forced closure of the hospitals. The last case was reported in June 1995.

 Separate emergences of Ebola virus (Zaire) were detected in

Gabon in 1994–2003, usually in association with deep-forest exposure and subsequent familial and nosocomial transmission.  After its first documented activity in 1976, the Sudan Ebola species returned in epidemic form to cause an indolent outbreak in Uganda in 2000–2001. This outbreak claimed the lives of 224 (53%) of 425 patients.

Past important outbreaks of EHF Year

Country

Cases

Deaths

Case fatality

2012

DRC

57

29

51%

2012

Uganda

24

17

71%

2008

DRC

32

14

44%

2007

Uganda

149

37

25%

2007

DRC

264

187

71%

2005

Congo

12

10

83%

2003 (Jan-Apr)

Congo

143

128

90%

2000

Uganda

425

224

53%

1995

DRC

315

254

81%

1976

Sudan

284

151

53%

1976

DRC

90%

Clinical Manifestations  Incubation period 7-10 days(range 3-16 days)

 Abrupt development of fever, severe headache, malaise, myalgia, 

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nausea and vomiting. Continued fever is associated with diarrhoea (often severe), chest pain (accompanied by cough) and depressed mentation. Maculopapular rash appears around day 5-7 and is followed by desquamation; in light skinned people. Bleeding may begin about this time and is apparent from any mucosal site and into the skin. Additional findings include edema of the face, neck, and/or scrotum; hepatomegaly; flushing; conjunctival injection; and pharyngitis.

 Around 10–12 days after the onset of disease, the sustained

fever may break, with improvement and eventual recovery of the patient.  Recrudescence of fever may be associated with secondary bacterial infections or possibly with localized virus persistence.  Late hepatitis, uveitis, and orchitis have been reported, with isolation of virus from semen or detection of PCR products in vaginal secretions for several weeks.

Laboratory findings  Leokopenia - common early; neutrophilia onsets later

 Low platelet count- sometimes as low as 50,000/L.  High SGPT &SGOT; sometimes high bilirubin.  Elevated serum amylase level sometimes confusing with

pancreatitis.  protinuria  Derranged kidney function.  Evidence of DIC – raised FDP, d-dimer.

Diagnosis  Virus isolation by cell culture.

 Antigen detection with ELISA – robust diagnostic modality  Reverse transcription PCR  IgM and IgG in recovering patients.

 Indirect fluorescent antibody test.

Treatment  No virus specific therapy is available.

 ive treatment –treatment of shock

- Balancing the patient’s fluids and electrolytes -Maintaining their oxygen status and blood pressure -Treating them for any complicating infections  Early ive care with rehydration, symptomatic treatment improves survival.  There is as no licensed treatment proven to neutralize the virus but a range of blood, immunological and drug therapies are under development.

 An adenovirus-vectored Ebola glycoprotein gene has proved

protective in nonhuman primates and is undergoing phase 1 trials in humans.

Prevention & control  No vaccine or antiviral drug currently available

 Barrier nursing precautions – use of

personnel protective

equipments, gloves ,mask, isolation.  Community engagement is key to successfully controlling outbreaks.  Good outbreak control relies on applying a package of interventions, namely case management, surveillance and tracing, a good laboratory service, safe burials and social mobilisation.