What is Ebola  virus  and why the scare?

(This post has been updated following new breakthrough in prevention of Ebola virus infection)

 

Ebola is a RNA. virus belonging to the filoviridae group.Marburg is the  other virus  belonging to this group which causes a similar disease but is antigenically distinct. Ebola causes Haemorrhagic fever.

Ebola virus Infection.Image  courtesy sscreations at Freedigitalphotos.net

It has 4 distinct family member all of which are of African origin . Ebola is a category 4 pathogen , due to its high associated mortality and potential for aerosol spread. No aerosol spread of Ebola has been documented in the current epidemic  . There has been more than 20 Haemorrhagic fever outbreaks due to these 2 viruses but none has documented transmission before  patient is  symptomatic. Zaire Ebola virus is responsible for the 2014  West Africa outbreak. Experts opine that the current epidemic , occurred mainly due to lack of personal protection and absence of   universal barrier nursing care .2 things which are unfortunately often the cause behind epidemics in  developing countries.  

Ebola virus Infection can cause Epidemics.Image  courtesy Stuart Miles at Freedigitalphotos.net

Current status Ebola

As per data available with CDC  the total number of laboratory confirmed cases (till 7th December 2014) is 11288.Of these the total number of deaths reported is 6388.This outbreak of Ebola haemorrhagic fever is the worst documented epidemic in West Africa in recent history.Grim stats no doubt but protection is possible.Knowledge like always is power if applied properly.

Who can spread Ebola?

Bats are  reservoirs  with transmission from bats to other wild animals and humans

• Symptomatic cases are contagious.
• Incubation period 7 to 10days ( range 3 to days)

• Symptoms:fever, severe headache, malaise , myalgia, nausea, vomiting, diarrhea,chest pain, cough.
• Bleeding may begin about days later from. any mucosal site and into the skin.

Ebola virus infection.Image courtesy kjnnt at Freedigitalphotos.net 

 

• Even when patient is declared cured virus may persist in semen and some other body fluids for several  weeks.

How is Ebola virus spread?

Direct contact of mucous membrane, cut skin with:

• Blood products of Ebola cases
• Body fluids like sweat, saliva vomit, urine, faeces, semen of Ebola cases
• Needles, syringes etc  contaminated with blood , body fluids of Ebola cases.

How does Ebola virus spread

• Meat of infected animals
• Viral load increases with severity of illness of patients.

Ebola virus is a Biosafety level 4 pathogen  as it is associated with high fatality rate  and potential  for aerosol infectivity. However generally sick patients rarely generate sufficient amount of aerosols to pose a significant hazard. But large droplets ( in the form of splashes or sprays) may cause potential hazard to exposed mucosa.Thus personal protective equipment for all healthcare workers  is the best way to control spread.

Who needs protection?

High Risk Exposure:

Risk of Ebola virus Infection .Image courtesy Stuart Miles at Freedigitalphotos.net

 

• All family members in direct  contact with symptomatic cases.
• All care givers  of symptomatic  cases.
• Healthcare workers  exposed to  Ebola   cases .
• Travellers travelling to region  with Ebola cases.
• All staff responsible for waste disposal of Ebola cases.All high risk

All high risk exposure cases need to be monitored,   together  with restriction of  travel and general public activity.

 

How to protect yourself?

Ebola virus infection prevention.Image courtesy Stuart Miles at Freedigitalphotos.net

 

• Ebola virus is said to be inactivated by heat at about  60 degree celsius.It is also  sensitive to household bleach etc.Personal protective equipment is essential for protection in a healthcare setup.Important guidelines  to ensure  your safety includes:
• Wash hands, use hand sanitizer
•  Use household bleach , disinfectants on surfaces contaminated with blood, body fluids
• Use personal protective gear/ equipments if you are working in a healthcare setup / caring for patients with Ebola virus disease
• Dispose  of used  contaminated,needles, bedding, clothing in a hygienic manner.
• Do inform appropriate health care authority in case ,you are returning from travel in country with known outbreak of Ebola cases and running fever  or any other symptoms  of Ebola within 21 days of return.
• Inform appropriate healthcare authority  in case you have been in direct ,unprotected contact with any patient of Ebola.

Diagnosis

• Real Time PCR
• Antigen detection by ELISA
• Virus isolation
• immunohistochemistry  and HPE
• Serology for IgM and IgG antibodies (only in confirmed cases)

 

Treatment

• Supportive care is the mainstay of treatment
• Maintenance of fluid,  electrolyte  levels and acid -base balance
• Monitoring vital parameters
• Management of Shock and other complications when they appear

Human convalescent serum is a potential mode of treatment which is currently under evaluation by WHO.There exists no vaccine , antivirus drug ,immune mediated or any other definitive treatment for the Ebola virus.

 

Update on Ebola  Virus management

A ray of hope .Prevention of Infection during epidemics of Ebola virus is under investigation. A  rVSV -vectored  ebola vaccine which is expressing the Ebola surface glycoprotein is  being .

 

Initial results indicate that  the rVSV-ZEBOV vaccine will be highly  efficient in preventing Ebola virus disease. 

It’s safety profile isgood.It is most likely be given to the population at risk by a ring vaccination strategy during Ebola outbreaks.

 

Hope, Pray and Prevent   …. take home message

As always PREVENTION is  better than cure.Extensive healthcare support provided by Doctors without borders and WHO has been possible due to strict adherence of these basic guidelines. Humane behaviour ,care  towards those affected  together with your own personal protection  will help in fighting  this  fatal disease destroying Africa , with potential to destroy the world. Case fatality rate is as high as 50%to 70 % in the current epidemic.Significantly this rate is much lower when there is  a good healthcare setup with intensive  care facilities. Strict isolation and management of index cases is the best way to combat the  disease  when it appears in new territories. Training of airport staff who are screening travellers  and  exhaustive  isolation   and treatment  protocols should be in place for all facilities responsible for taking care of cases and suspected cases. Above all Personal protective gear  and training  should be provided for all healthcare workers faced with the responsibility of caring for the sick. Unnecessary public hysteria , panic and social shunning of those suspected of this disease in other parts of the world will only help to spread the disease beyond its natural habitat. Stay informed, avoid  panic and take care, the rest is God’s Will!

References

Harrison Internal Medicine

www.cdc.gov/vhf/ebola/  

Disclaimer:The purpose of this article is strictly for educational interest and is not meant as a replacement for professional opinion.

 

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