Jadhav Santosh1*, Mali Audumbar1, Tamboli Ashpak2
Department of Pharmaceutics, Sahyadri College of Pharmacy, Methwade, Sangola-413307, Solapur, Maharashtra, India1.
Department of Pharmaceutical chemistry, Sahyadri College of Pharmacy, Methwade, Sangola-413307, Solapur, Maharashtra, India2.*

Since the current Ebola Virus Disease (also referred to as Ebola Haemorrhagic Fever) outbreak began in Guinea in December of 2013, the outbreak now involves trans-mission in Guinea, Liberia, Nigeria, and Sierra Leone. Ebola haemorrhagic fever (EHF) is a zoonosis affecting both human and non-human primates (NHP). Ebola virus (formerly officially designated Zaire Ebolavirus, or EBOV) was first seen infecting humans in African continent; especially  Sudan, Democratic Republican of Congo, Zaire and nearby countries. Fruit bats of the Pteropodidae family are considered to be the natural host of the Ebola virus. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. The World Health Organization (WHO) reports that this is the largest Ebola Virus Disease (EVD) outbreak ever recorded. EVD outbreaks have a case fatality rate ofup to 90%. The research is on-going on development of making vaccine to curb this virus yet licensed success or specific treatment is not achieved.


PharmaTutor (ISSN: 2347 - 7881)

Volume 3, Issue 4

Received On: 05/01/2015; Accepted On: 15/02/2015; Published On: 01/04/2015

How to cite this article: S Jadhav, A Mali, A Tamboli; Resources, Guidance, Control and Prevention for Ebola Virus Disease- An Overview; PharmaTutor; 2015; 3(4); 12-20

The disease is caused by infection with Ebola virus, named after a river in the Democratic Republic of the Congo (formerly Zaire) in Africa, where it was first recognized. The Ebola virus disease (EVD),  previously  known  as  Ebola  haemorrhagic  fever  (Ebola  HF)  is  a  severe condition caused by a virus belonging to genus Ebolavirus, family Filoviridae and order Mononegavirales. The virus is one of two members of a family of RNA viruses called the Filoviridae[1]. These five viruses are-

Bundibugyo virus (BDBV):

Ebola virus or Zaire Ebola virus (EBOV):
This  is most fatal among all fiveand  has  the  highest case-fatality  rate,  up  to  90%  in  some epidemics. The first outbreak took place on 26 August 1976 in Yambuku. MabaloLokela, a 44-year-old schoolteacher, became the first recorded case. The symptoms resembled malaria, and subsequent patients received quinine. The initial transmission was believed to be due to reuse of the needle for Lokela's injection without sterilization.  Subsequent transmission was also due to lack of barrier nursing and the traditional burial preparation method, which involves washing and gastrointestinal tract cleansing[2].

Sudan virus (SUDV):
The virus was the second species of Ebola emerging simultaneous with the Zaire virus. It was believed to have originated amongst cotton factory workers in Nzara, Sudan, with the first case reported as a worker exposed to a potential natural reservoir. The carrier is still unknown. The most recent outbreak occurred in May 2004. 20 confirmed cases were reported in Yambio County, Sudan, with five deaths resulting. The average fatality rates for were 54% in 1976, 68% in 1979, and 53% in 2000 and 2001[3].

Tai Forest virus (TAFV):
Also referred to as Ivory Coast Ebolavirus and Tai Ebola virus; it was first discovered among chimpanzees from the Tai Forest in Côte d'Ivoire, Africa. Studies of tissues taken from the chimpanzees showed results similar to human cases during the 1976 Ebola outbreaks in Zaire and Sudan. As more dead chimpanzees were discovered, with many testing positive to Ebola using molecular techniques. The source of contamination was believed to be the meat of infected Western Red Colobus monkeys, uponwhich the chimpanzees preyed. One of the scientists performing the necropsies on the infected chimpanzees contracted Ebola. She develops symptoms similar to those of dengue fever approximately a week after the necropsy, and was transported to Switzerland for treatment. She was discharged from hospital after two weeks and had fully recovered six weeks after the infection.

Reston virus (RESTV):
Is not thought to be disease-causing in humans. Discovered during an outbreak of Simian hemorrhagic fever virus (SHFV) in crab-eating macaques from Hazleton Laboratories (now Covance) in 1989.  Since  the  initial  outbreak  in  Reston, Virginia,  it  has  emerged  in  the  Philippines, Siena Italy, and Texas. It is non-pathogenic to humans however hazardous in monkeys[4].

The first Southern African Centre for Infectious Disease Surveillance (SACIDS) conference on ‘One Africa, One Health’ served as inspiration for this review to illustrate the concept through a typical emerging infection. Ebola haemorrhagic fever (EHF) is caused by any of above five genetically distinct members. Zaire Ebola virus has been associated with only one human case. Reston Ebola virus has only caused disease in non-human primates (NHP) and was found in swine suffering from porcine reproductive and respiratory disease syndrome. Zaire, Sudan and Bundibugyo Ebola viruses are responsible for most of the EHF outbreaks[5]. But ZEBOV constitutes a particularly serious threat to both human and NHPs in sub-Saharan Africa. Ebola haemorrhagic fever has been associated with large human outbreaks, with case fatality rates for ZEBOV as high as 90%. The case fatality rate of EBOV in NHP is unknown but some ecological data suggest that EBOV has contributed to declines of up to 98% of local great ape populations in Gabon and the Republic of Congo. EHF typically appears in sporadic outbreaks coinciding with the rainy season, and is usually spread in humans within a health-care setting[6].

Fig. 1 Ebola virus[7].

Etiology (causes)
Ebola virus belongs to the family Filoviridae, in the order Mononegavirales which includes Rhabdoviridae and Paramyxoviridae. Between people, Ebola disease spreads only by direct contact with the blood or body fluids of a person who has developed symptoms of the disease. Body fluids that may contain Ebola viruses include saliva, mucus, vomit, feces, sweat, tears, breast milk, and urine.Ebola viruses contain single-stranded, non-infectious RNA genomes. Bolavirus genomes contain seven genes including 3'-UTR-NP-VP35-VP40-GP-VP30-VP24-L-5'-UTR. As all filoviruses, ebolavirions are filamentous particles that may appear in the shape of a shepherd's crook, of a "U" or of a "6," and they may be coiled, toroid or branched. In general, ebolavirions are 80 nanometers (nm) in width and may be as long as 14,000 nm.It contains one molecule of linear, single-stranded, negative-sense RNA of 4.2x106 Da.

Person under investigation
A person who has both consistent symptoms and risk factors as follows:  1) Clinical criteria, which includes fever of greater than 38.6 degrees Celsius or 101.5 degrees Fahrenheit, and additional symptoms such as severe headache, muscle pain, vomiting, diarrhoea, abdominal pain, or unexplained haemorrhage; and 2) Epidemiologic risk factors within the past 21 days before the onset of symptoms, such as contact with blood or other body fluids or human remains of a patient known to have or suspected to have EVD; residence in—or travel to—an area where EVD transmission is active*; or direct handling of bats or non-human primates from disease-endemic areas.

Probable  case:
A PUI whose epidemiologic risk factors include high or low risk exposure.

Confirmed case:
A case with laboratory-con-firmed diagnostic evidence of Ebola virus infection.

Exposure  risk levels:
Levels of exposure risk are defined as follows:
* High- risk exposures
A high-risk exposure includes any of the following:
• Percutaneous (e.g., needle stick) or mucous membrane exposure to blood or body flu-ids of EVD patient
• Direct skin contact with or exposure to blood or body flu-ids of, an EVD patient without appropriate personal protective equipment (PPE)
• Processing blood or body fluids of a confirmed EVD patient without appropriate PPE or standard biosafety precautions.
• Direct contact with a dead body without appropriate PPE in a country where an EVD outbreak is occurring*

* Low-risk exposures
A low-risk exposure includes any of the following:

• Household contact with an EVD patient

• Otherclose contact with EVD patients in health care facilities or community settings. Close contact is defined as:
- Being within approximately 3 feet (1 meter) of an EVD patient or within the patient’s room or care area for a prolonged period of time (e.g., health care personnel, household members) while not wearing recommended personal protective equipment (i.e., standard, droplet, and contact precautions; see Infection Prevention and Control Recommendations) ebola  virus
- Having direct brief contact (e.g., shaking hands) with an EVD patient while not wearing recommended personal protective equipment

• Brief interactions, such as    walking by a person or moving through a hospital, do not constitute close contact

Early recognition is critical for infection control [8]:

According  to  the WHO  (World  Health  Organisation)  this  disease can  be  transmitted from close contact with  the blood,  secretions,  organs  or  other  bodily  fluids of  infected  animals  (commonly  monkeys, gorillas, chimpanzees, baboon and fruit bats). In humans  the  disease  can  be transmitted  by  the following methods [,9,10]. Filo viruses are believed to be zoonotic, meaning they are transmitted to humans by animals. The natural reservoirs, or animal hosts, of Ebola and Marburg viruses are not known. The viruses can replicate, or reproduce, in certain types of bats native to the areas where the viruses are found, so some researchers think that these bats could be the natural reservoirs.

Once the virus has been transmitted to a human, it can then be spread through person-to-person contact. People can be exposed to Ebola and Marburg viruses from direct contact with the blood or secretions of an infected person.

Nosocomial transmission, or the spread of disease within a healthcare setting, also occurs, making the use of protective clothing and the disposal of needles and syringes crucial to preventing the spread of infection.



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