Corona Virus VS Influenza Virus, COVID-19 Virus

Difference between Coronavirus (COVID-19) and Influenza virus:

Coronavirus (COVID-19) has similar signs and symptoms to H.influenza, and both are more common in the winter season.

Coronavirus is a single-stranded linear RNA virus. This gives S/S like the common cold.

No doubt that Coronavirus gives more severe disease than the Influenza virus.

Influenza virus:

1. Influenza viruses are of three types A, B, and C. Type A infects humans, and the other two types infect mammals, swine, and birds. Type B and C are isolated from humans.
2. Structure: Influenza virus measure 80 to 120 nm, enveloped single-stranded RNA virus.
3. Influenza causes a self-limited disease. But it can cause pneumonia and serious illness in elderly patients.
4. The incubation period is 2 days, and it may range from 1 to 4 days.
5. It can resolve in 3 to  7 days.
6. Still, there is a devastating Influenza infection in history in 1918, when 548,452 persons in the USA, 12.5 million people in India, and 20 million people worldwide died from the Influenza virus.
7. The complication of Influenza:
   1. Older adults and immunocompromised patients may suffer severe complications and have pneumonia.
   2. This viral makes patients more susceptible to bacterial infections.
   3. These patients may have bacterial pneumonia with Staph. Aureus and Strep. pneumoniae.
8. Diagnostic test for the Influenza infection:
   1. Isolation of the virus on culture. This will give genetic and antigenic analysis.
   2. Detection of the viral proteins and will help to decide the antiviral drugs.
   3. Diagnosing viral nucleic acid (RNA) by reverse transcriptase enzyme (PCR). This is a susceptible method.
   4. Serological test: Specific antibody >4 times the normal in 2 weeks.
9. Vaccine for Influenza: The virus grows in chick embryos, which are then inactivated, purified, and used as vaccines.
   1. This vaccine contains Influenza A and B.
   2. The vaccines should be given to the elderly, immunocompromised people, and healthcare workers.
   3. The protection by vaccinations is around 70%.

Coronaviruses:

1. Coronaviruses are 100 to 150 nm, enveloped, single-stranded viruses.
2. These viruses are named because of their club-shaped surface projections, which resemble a crown.
   

   Coronavirus structure

3. There are three respiratory coronaviruses.”
   1. Coronavirus 229E (α- coronavirus).
   2. Coronavirus NL63 (α- coronavirus).
   3. Coronavirus OC43 (β-coronavirus).
   4. Other viruses are:
      1. MERS-CoV is β-coronavirus that causes Middle East Respiratory Syndrome (MERS).
      2.  SARS-CoV is β-coronavirus causes severe acute respiratory syndrome (SSRS).
      3. SARS-CoV-2 (the Novel coronavirus that caused coronavirus disease in the 2019 epidemic, so-called COVID-19).
   5. The most common viral infection in this epidemic was caused by 229E, NL63, OC43, and HKUI.
4. These are the most common causes of the common cold.
5. Coronaviruses give rise to 4% to 15% of respiratory diseases per year, and this may reach 35% at peak time.
6. Most of the coronavirus infections occur in winter and early spring.
7. But these cases are detected throughout the year.
8. Immunity to infection is incomplete, and reinfection is common.
9. Incubation period:
   1. The appearance of the common cold due to coronaviruses ranges from 2 to 5 days.

Signs and symptoms of Coronavirus:

A typical infection is presented as coryza (common cold) and can not be distinguished from other viruses.

Watch for the following S/S:

1. History of fever and chills.
2. There is a sore throat.
3. There is congestion of the nose and congestion.
4. The patient may have a cough.
5. There is fatigue.
6. Headache.
7. Muscle or body pain and aches.
8. Sore throat.
9. Nausea and vomiting.
10. There Ia loss of smell and taste.
11. The patient will develop shortness of breath or difficulty in breathing.
12. The patient may develop diarrhea.

SARS  Coronaviruses

1. SARS-CoV is a novel coronaviruses identified as a clinical syndrome.
2. This was first identified as a cause of atypical pneumonia in Guangdong province, China, in November 2002.
3. In the next 6 months, the virus spread to various parts of the world, 8000 cases were reported sick, and 774 patients died.
4. The most affected countries were China, Hong Kong, Canada (Toronto), Taiwan,  and Singapore.
5. The source was animals, but the primary reservoir not certain. It was found in the living animals market.
6. The spread of the SARS-CoV is efficient between humans.
   1. The most common mode of spread is personal close contact.
   2. This spread by the infectious droplets from the cough or sneezing from the infected person.
      

      Mode of Coronavirus spread.

   3. Other modes of spreads are:
      1. Fomites.
      2. Contaminated hands (self-inoculation).
      3. Small particles in aerosols.
      4. Feco-ornal transmission.
      5. Transmission may take place through endotracheal intubation, bronchoscopy, and treatment with aerosolized medications.
      6. Person to person spread is more common in health care workers and hospitals.
      7. Spread not documented before the onset of symptoms or more than 10 days after the settling of fever.
7. Clinical features:
   1. The incubation period is typically  2 to 7 days.
   2. In some cases, the incubation period maybe 10 days and rarely is 14 days.
   3. Chest X-Rays show evidence of pneumonia in 60% to 100% of the cases.
      1. Typically, the peripheral lung tissue’s involvement is unilateral (usually right lung), and there is no cavitation.
   4. There may be pleural effusion.
   5. There is lymphadenopathy.
   6. 67% of the case with normal X-Ray shows changes on high-resolution CT scan.
8. Diagnosis:
   1. RNA detection by the RT-PCR (reverse transcriptase-PCR).
   2. The virus may be cultured.
   3. Serological tests.
   4. Viruses can be detected from the:
      1. Nasopharynx.
      2. Throat.
      3. Nose.
      4. Lower respiratory tract.
      5. This can also be found in the stool, serum, and plasma.
9. Prognosis:
   1. 1/3 of the cases of corona improve clinically.
   2. The rest of the patients have a progressive disease with diarrhea, increasing tachypnea, shortness of breath.
   3. There are abnormal findings on pulmonary examination and X-Rays of the chest.
   4. 20% to 30% of patients need admission to the ICU. Usually, mechanical ventilation and roughly 10% may not survive.
   5. Death is usually due to respiratory failure, multiple organ failures, sepsis, or other complications.
   6. Prognosis is poor in older patients and with underlying disease.

The major differences between Coronaviruses and Influenza virus: