What is Ebola ?

Ebola is a virus that causes a severe and often fatal disease in humans and nonhuman primates (such as monkeys, gorillas, and chimpanzees). The virus is named after the Ebola River in the Democratic Republic of Congo (formerly Zaire), where it was first identified in 1976.

Ebola is a viral hemorrhagic fever, which means it causes fever and bleeding (hemorrhage) inside and outside the body. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.

Symptoms of Ebola usually appear 8-10 days after infection, but they can appear anywhere from 2 to 21 days after infection. Early symptoms include fever, muscle pain, headache, and sore throat. As the disease progresses, it can cause severe bleeding (hemorrhage), organ failure, and death.

There is no specific treatment for Ebola, but supportive care can help manage the symptoms. This can include providing fluids and electrolytes to prevent dehydration, maintaining oxygen levels and blood pressure, and treating other infections if they occur.

Ebola outbreaks have occurred primarily in Africa, but there have been a small number of cases in other parts of the world. The 2014-2016 Ebola outbreak in West Africa was the largest and most complex Ebola outbreak since the virus was first identified. It was declared over by the World Health Organization (WHO) in June 2016, but it has flared up again in the Democratic Republic of Congo and other countries.

Genomic Organization of Ebola Virus

Ebola virus is a negative-sense single-stranded RNA virus. This means that the viral genome is made up of a single strand of RNA (ribonucleic acid) that is in the opposite sense to the viral mRNA. The viral genome encodes for seven structural proteins and several nonstructural proteins.

The structural proteins of Ebola virus include:

1. nucleoprotein (NP)
2. polymerase cofactor (VP35)
3. matrix protein (VP40)
4. glycoprotein (GP)
5. RNA-dependent RNA polymerase (L)
6. small RNP-specific protein (VP30)
7. transcription activator (VP24)

The NP protein is the major structural protein and is involved in virus assembly and maturation. The VP35 protein is a multifunctional protein that is involved in viral replication and the evasion of the host immune response. The VP40 protein is involved in the formation of virus-like particles and is important for virus budding and release. The GP protein is the viral envelope protein and is involved in virus attachment and entry into host cells. The L protein is the viral RNA-dependent RNA polymerase and is responsible for synthesizing the viral mRNA. The VP30 protein is involved in viral transcription and replication. The VP24 protein is involved in the regulation of viral gene expression.

Ebola virus also has several nonstructural proteins, including:

1. VP15
2. VP19c
3. VP24-associated protein (VAP)
4. VP25

The functions of these nonstructural proteins are not well understood, but they are thought to be involved in the regulation of viral gene expression and the evasion of the host immune response.

Symptoms of Ebola

Symptoms of Ebola usually appear 8-10 days after infection, but they can appear anywhere from 2 to 21 days after infection. Early symptoms include:

1. Fever: A high fever is one of the most common symptoms of Ebola. The fever can be accompanied by chills and sweats.
2. Muscle pain: Ebola can cause muscle pain, especially in the back, legs, and arms. The pain can be severe and may get worse over time.
3. Headache: A headache is a common symptom of Ebola, and it can be severe. The headache may be accompanied by a feeling of pressure in the head.
4. Sore throat: Some people with Ebola may have a sore throat, which can make it painful to swallow.

As the disease progresses, it can cause more severe symptoms, such as:

5. Vomiting and diarrhea: Both of these symptoms can cause a person to lose a lot of fluids and can lead to dehydration.
6. Rash: Some people with Ebola develop a rash, which can be made up of small bumps or larger patches of red, raised skin.
7. Bleeding: Ebola can cause bleeding (hemorrhage) inside and outside the body. This can include bleeding from the gums, nose, eyes, or rectum.
8. Organ failure: As the disease progresses, it can cause organ failure, which can be life-threatening.

If you think you may have Ebola, you should seek medical attention immediately. The earlier treatment is started, the better the chances of survival.

What is Zika?

Zika is a virus that is transmitted to people through the bite of an infected mosquito. The virus was first identified in Uganda in 1947 and is found in tropical and subtropical regions of the world, including parts of the Americas, Africa, and Asia.

Most people who are infected with Zika do not have symptoms, or the symptoms are mild. The most common symptoms of Zika are fever, rash, joint pain, and conjunctivitis (red eyes). These symptoms usually last for a few days to a week.

Zika can also cause serious complications, including:

1. Birth defects: If a pregnant woman is infected with Zika, the virus can cause birth defects in the baby, including microcephaly (a small head and brain) and other brain abnormalities.
2. Guillain-Barré syndrome: This is a rare condition in which the body’s immune system attacks the nerves, causing weakness and tingling sensations. Zika has been linked to an increased risk of developing Guillain-Barré syndrome.
3. Other neurological complications: Zika has been linked to other neurological complications, including inflammation of the brain (encephalitis) and inflammation of the spinal cord (myelitis).

There is no specific treatment for Zika, but symptoms can be managed with rest, hydration, and pain medication. There is no vaccine to prevent Zika. To reduce the risk of getting infected with Zika, people should use insect repellent, wear long-sleeved shirts and pants, and take other steps to avoid mosquito bites.

Genomic Organization of Zika Virus

Zika virus is a positive-sense single-stranded RNA virus. This means that the viral genome is made up of a single strand of RNA (ribonucleic acid) that is in the same sense as the viral messenger RNA (mRNA). The viral genome encodes for a single polyprotein, which is then cleaved by viral and host proteases into smaller functional proteins.

The genomic organization of Zika virus is similar to that of other flaviviruses, such as dengue virus and West Nile virus. The Zika virus genome is about 10,800 nucleotides in length and is organized into three structural proteins (C, prM, and E) and seven nonstructural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5).

The C protein is the major structural protein and is involved in virus assembly and maturation. The prM protein is also involved in virus assembly and is present in immature virions. The E protein is the viral envelope protein and is involved in virus attachment and entry into host cells.

The nonstructural proteins are involved in various functions, including replication, transcription, and modulation of the host immune response. The NS1 protein is a glycoprotein that is involved in the evasion of the host immune response. The NS2A and NS2B proteins are involved in the cleavage of the viral polyprotein. The NS3 protein has enzymatic activities, including protease and helicase activities. The NS4A and NS4B proteins are involved in the replication of the viral genome. The NS5 protein is the viral RNA-dependent RNA polymerase and is responsible for synthesizing the viral mRNA.

Symptoms of Zika Virus

Most people who are infected with Zika virus do not have symptoms, or the symptoms are mild. The most common symptoms of Zika are:

1. Fever: Some people with Zika virus have a low-grade fever.
2. Rash: Many people with Zika virus develop a rash, which can be made up of small bumps or larger patches of red, raised skin. The rash often appears on the face, chest, and arms.
3. Joint pain: Some people with Zika virus have joint pain, especially in the hands and feet. The pain can be severe and may last for a few days to a week.
4. Conjunctivitis (red eyes): Some people with Zika virus have red eyes, which can be accompanied by pain, itching, and discharge.

Symptoms of Zika virus usually last for a few days to a week. If you think you may have Zika virus, you should seek medical attention. There is no specific treatment for Zika, but symptoms can be managed with rest, hydration, and pain medication. If you are pregnant or planning to become pregnant, you should talk to your healthcare provider about the potential risks of Zika virus.

Similarities Between Ebola and Zika

Here are some similarities between Ebola and Zika:

1. Both viruses are transmitted through contact with bodily fluids (for Ebola) or the bite of an infected mosquito (for Zika).
2. Both viruses can cause fever, muscle pain, and fatigue.
3. Both viruses can cause serious complications, including organ failure (for Ebola) and birth defects (for Zika).
4. There is no specific treatment for either virus, but supportive care can help manage the symptoms.
5. Both viruses have been responsible for outbreaks in different parts of the world.
6. Both viruses are RNA viruses and have a similar genomic organization, with structural and nonstructural proteins.
7. Both viruses have been linked to neurological complications, including inflammation of the brain (encephalitis) and inflammation of the spinal cord (myelitis).
8. Both viruses are classified as neglected tropical diseases, which means they receive little attention and funding for research and control efforts.

Difference Between Ebola and Zika

1. Definition: Zika is a mosquito-borne flaviviral disease that causes birth abnormalities, whereas Ebola is a fatal virus disease that occurs periodic epidemics primarily in Africa.
2. Transmission: Ebola is primarily transmitted through contact with the bodily fluids of an infected person, while Zika is primarily transmitted through the bite of an infected mosquito.
3. Symptoms: Both viruses can cause fever, muscle pain, and fatigue, but there are some key differences in the symptoms they cause. Ebola can also cause severe bleeding, while Zika is more likely to cause a rash and conjunctivitis (red eyes).
4. Associate with: Ebola virus disease is associated with a high mortality rate and a very high pregnancy and neonatal loss rate, whereas zika virus disease is associated with zika syndrome in newborns.
5. Complications: Both viruses can cause serious complications, but the complications they cause differ. Ebola can cause organ failure and death, while Zika is more likely to cause birth defects in babies born to infected mothers and neurological complications in adults.
6. Treatment: There is no specific treatment for either virus, but supportive care can help manage the symptoms.
7. Geographical distribution: Both viruses are found in different parts of the world. Ebola is found in certain parts of Africa, while Zika is found in tropical and subtropical regions of the Americas, Africa, and Asia.

Conclusion

In summary, Ebola and Zika are two different viruses that can cause severe illness in humans. They have different modes of transmission, different sets of symptoms, and different complications. Ebola is transmitted through contact with bodily fluids and can cause bleeding and organ failure, while Zika is transmitted through the bite of an infected mosquito and can cause birth defects and neurological complications. There is no specific treatment for either virus, but supportive care can help manage the symptoms. They are also found in different parts of the world, with Ebola being found in certain parts of Africa and Zika being found in tropical and subtropical regions of the Americas, Africa, and Asia.