Wed | Feb 22, 2017

Ebola the beginnings of a deadly disease

Published:Wednesday | August 13, 2014 | 12:00 AM
Medical workers roll patient Nancy Writebol, the second American aid worker infected with Ebola, into Emory University Hospital in Atlanta last week.
Dr Fenton Ferguson, minister of health, and Dr Marion Bullock DuCasse, principal medical officer and director, Emergency, Disaster Management and Special Services, the Ministry of Health, giving an update on Jamaica's Preparedness and Response Strategy. - Rudolph Brown/ Photographer
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Anastasia Cunningham, Health Coordinator

Formerly known as Ebola haemorrhagic fever, the Ebola virus disease is a grave, often deadly disease, with a case-fatality rate of up to 90 per cent, although the 2014 outbreak has killed around 55 to 60 per cent of those infected. It is one of the world's deadliest diseases, with no proven cure or vaccines to treat or prevent the disease.

According to the last update from the World Health Organisation (WHO), in this recent outbreak, Ebola has, so far, killed 961 persons in West Africa, with approximately 1,779 suspected and reported cases across Guinea, Liberia, Nigeria and Sierra Leone; and it continues to spread. This is currently the largest Ebola outbreak ever recorded.

Ebola tests were recently done on suspected persons in the United States and Canada, but the results were negative.

Due to the scale of the current outbreak, WHO has declared it a "public health emergency of international concern".

Countries around the world, including Jamaica, have moved their Ebola-response level to high alert.

"Every country has to put in place a response mechanism for the virus. Jamaica already has a plan in place that is now being further developed," noted Dr Marion Bullock DuCasse, director, Emergency, Disaster Management and Special Services in the Ministry of Health.

History

Ebola first appeared in 1976 in two closely spaced outbreaks - in Zaire, Sudan and in Yambuku, Democratic Republic of Congo in Africa. The latter was in a village situated near the Ebola River, from which the disease takes its name.

The first outbreak of Ebola (Ebola-Sudan) infected more than 284 people, with a mortality rate of 53 per cent. Months later, the second Ebola virus emerged (Ebola-Zaire - EBOZ), infecting 318 persons, with the highest mortality rate of any of the Ebola viruses of 90 per cent.

The third strain of Ebola, Ebola Reston (EBOR), was first identified in 1989, when infected monkeys were imported into Reston, Virginia, in the United States from Mindanao in the Philippines.

While the last known strain of Ebola, Ebola Cote d'Ivoire (EBO-CI), was discovered in 1994, when a female ethologist performing a necropsy on a dead chimpanzee from the Tai Forest, Cote d'Ivoire, accidentally infected herself during the necropsy.

In October 1976, Dr Frederick Murphy, then chief of the viral pathology branch at the Centers for Disease Control and Prevention, was the first to see this new deadly disease upfront while studying it in Atlanta.

However, despite tireless efforts and numerous and intense research since it first surfaced, Ebola's natural reservoir was never identified, so how humans were first infected is unknown. Researchers theorised that the first human became infected through contact with an infected animal.

TRANSMISSION/SPREAD

Ebola is not contagious like common viruses such as colds, flu or measles. This virus is transmitted through direct contact with broken skin, tissue, blood, or other bodily fluid (secretion such as stool, saliva, urine, and semen) of infected persons.

The Ebola virus first spreads to humans by contact with the skin or bodily fluids of an infected animal (like a monkey, chimpanzee or fruit bat), then it moves from person to person through the same means. Persons with Ebola are most contagious in the later stages of the disease.

Persons are infectious as long as their blood and secretions contain the virus. In one case, the Ebola virus was isolated from semen 61 days after onset of the disease in a man who was infected in a laboratory.

Men who have recovered from the disease can still transmit the virus through their semen for up to seven weeks after recovery from the illness.

Those who care for a person with the virus, prepare or come in contact with or touch the body of someone who died from Ebola are also at high risk of getting the disease. The bodies of persons who died from Ebola are still contagious.

Ebola can also be contracted by touching contaminated needles or surfaces (for example, soiled clothing, bed linen).

During an outbreak, the diseasecan spread quickly in health-care facilities, hence the importance of quarantine areas for those with the virus, and adequate protective gear (such as a mask, gown, gloves, eye shield) for health-care workers and non-infected persons.

Proper cleaning and disposal of contaminated instruments, such as needles, syringes and gloves, is also important. If instruments are not disposable, they must be properly sterilised before being used again. Without adequate sterilisation of the instruments, the transmission can continue, and increase an outbreak.

The Ebola virus can also be transmitted to domestic animals, such as dogs and pigs.

Ebola cannot be transmitted through air, water, or food. A person who has Ebola, but has no symptoms, cannot spread the disease, either.

SYMPTOMS

The Ebola virus disease (sometimes called EVD) is a rare, but deadly virus that causes internal and external bleeding. Symptoms include the sudden onset of fever, intense weakness, muscle pain, headache, and sore throat.

This is followed by vomiting, diarrhoea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding. Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes.

The incubation period, that is, the time interval from infection with the virus to onset of symptoms, is two to 21 days.

It is difficult to know if a person has Ebola because the early symptoms mimic other diseases such as typhoid, malaria, hepatitis, meningitis, cholera. or leptospirosis, that is why it is important to visit a doctor as soon as possible, if you suspect you may have it.

If for any reason a person believes that he/she has been exposed to the virus, they should seek immediate medical treatment and reduce contact with other persons as much as possible.

DIAGNOSIS

If a person is suspected to have Ebola, that person should be isolated and immediately taken to a health-care facility. Samples will then be collected from the patient and tested for the virus.

If infection is confirmed, the patient will remain isolated and treatment administered. Severely ill patients require intensive supportive care.

Early diagnosis and proper treatment can make a difference between life and death.

TREATMENT/VACCINE

Although they are currently working on a vaccine, so far, no antiviral medications have proven effective in treating Ebola.

Care of patients with the disease include, providing fluids (oral and intravenous), maintaining normal blood pressure, providing oxygen as needed, blood transfusion, and treating other infections that develop.

According to pharmaceutical company GlaxoSmithKline, a clinical trial of an experimental preventative vaccine against Ebola is set to begin next month, and may be available for use by next year.

"We are targeting September for the start of clinical trials, first in the United States, and certainly in African countries, since that's where we have the cases," Jean-Marie Okwo Bele, the WHO's head of vaccines and immunisation, said last week.

"We think that if we start in September, we could already have results by the end of the year. And since this is an emergency, we can put emergency procedures in place, so that we can have a vaccine available by 2015."

GlaxoSmithKline is co-developing the vaccine with US scientists.

Several vaccines are also being tested, and a treatment made by San Diego-based Mapp Biopharmaceutical, ZMapp, has shown promising results on monkeys and may have been effective in treating two Americans recently infected in Africa.

PREVENTION/CONTROL

In the absence of effective treatment or a vaccine, public awareness of the risk factors for Ebola infection and the preventative measures persons can take is the only way to control and prevent infection, and possibly death.

Persons are being advised to:

Avoid travelling to areas with known outbreaks.

Wash hands frequently with soap, or use sanitiser if needed.

Avoid eating meat of wild animals.

Avoid contact with infected persons.

Avoid contact with wild animals, especially monkeys, gorillas, chimpanzees, or fruit bat.

If you have to be in contact with infected persons, especially health-care workers, always wear protective gear (gloves, mask, gown, eye shield).

Properly dispose of contaminated equipment, such as needles, syringes, gloves.

Properly sterilise instruments and contaminated areas (such as soiled clothing, bed linen, etc).

Keep infected persons isolated from non-infected persons.

Don't touch or handle the remains of persons who died from the disease. The bodies of persons who die from Ebola are still contagious. Allow specially trained persons to properly take care of the remains.

Infected persons who have recovered should not travel until at least 21 days after recovery, or when there are two negative Ebola tests done 48 hours apart.

Men who have recovered from the disease can still transmit the virus through their semen for up to seven weeks after recovery, so avoid sexual intercourse during that period or use a condom.

JAMAICA'S RESPONSE

Giving an update on Jamaica's Ebola Preparedness and Response Strategy last week, minister of health, Dr. Fenton Ferguson stated that Jamaica's points of entry are currently under surveillance, and vigilance and preparedness for the disease is in place. He also advised Jamaicans against non-essential travel to Ebola-infected countries.

"I would like to caution persons against non-essential travel to the affected areas, and to remind you of the importance of personal responsibility for health. The Ministry of Health has been keeping abreast of developments with respect to the Ebola situation in West Africa through the reports issued by the World Health Organization. I would like to stress that Jamaica does not at this time fall into the category of high-risk countries for transmission of the virus," Ferguson said.

"The capacity of our laboratory will be crucial in the event that we need to test for Ebola. I would like to assure you that we continue to enjoy the support of the University of the West Indies Virology Lab, the US Centres for Disease Control and Prevention, and the Caribbean Public Health Agency (CARPHA) for testing if needed."

For more information, persons may contact the Ministry of Health's Emergency Operations Centre at 1-888-663-5683 or 1-888-ONE LOVE.

yourhealth@gleanerjm.com