Coronavirus

What is Coronavirus disease( COVID19)?

• Newly discovered corona virus is a highly infectious virus. It spreads through droplets of saliva, discharge from the nose, cough or sneeze of an infected person.
• Majority of people have only mild respiratory symptoms such as sore throat, dry cough,headache, bodyache, fever or loss of taste/smell.  Some people may not have symptoms but they can still spread virus through saliva/nasal discharge.
• People with preexisting illness such as diabetes, heart disease, high BP, lung disease can have severe respiratory symptoms/ shortness of breath.
• Elderly(>60 year) people are at high risk of developing serious illness/death.
• Children are least affected, they are not at risk of developing serious disease.
• Any one with symptoms of covid19 must wear a mask and isolate themselves from others for atleast 2 weeks.

Pathophysiology:

• Virus enters our body through inhalation by nose. It stays in the lining of nose and throat in the surface receptor called ACE2 and replicate (7,8). During this stage we get fever,sore throat, body pain. If our immunity is strong enough, then we will get cured without any further progression. In some people virus goes down through wind pipe in to the lungs and alveoli, and pneumonia develops. So, cough and difficulty in breathing starts. Oxygen and other supportive treatments are needed. In some people its very severe where whole lungs gets infiltrated with fluid filled pus (ARDS-acute respiratory distress syndrome) and patients needs to be on ventilator to support breathing in intensive care setting. 
• ACE2 receptors are also present in Gastrointestinal lining (can cause diarrhoea), Blood vessels (hypotention / thrombosis), kidney (renal failure), and brain (encephalitis).

Among patients who are positive for COVID19, their symptoms/severity of disease can be categorized in 3 level.

1. Mild (75%): These people only have symptoms of cough, cold and fever in mild degree. They just need supportive care. No hospitalization needed.

Category 2 and 3 needs hospitalization(25%).

2. Moderate(15-20%) : These people have shortness of breath along with other symptoms. Their oxygen saturation is low. They need to get admitted to the hospital and need intra-nasal oxygen support. But, usually gets better in 3-4 days and can be safely discharged home with isolation order. 

3. Severe(10-15%): These people have difficulty in breathing and requires intubation and to be on Ventilator support (artificial respiration support) as their lungs get infiltrated. They can get cured in 7-10 days or they can become worse. There is possibility of severe progression of disease and development of stroke, heart attack, GI bleeding or severe hypotention which can lead to death. 

{% are calculated based on data at CDC and WHO. (1,2,3)}

Prevention: 

• Wear face mask to protect yourself and others. (2) It reduce touching of mouth and nose and less chances of spread. Any face mask is better than none. Someone posted this on facebook.

• This shows any type of face mask is better than none. 
• A systematic review by Maclntyre at el.(4) of 19 studies about face mask shows following findings:

-  Wearing mask can be beneficial to prevent community spread
- Mask is beneficial to Healthcare worker when worn continuously during the shift.

• Frequent hand washing with soap and water kills virus on surface of hand. 
  
  
  
• Avoid touching nose/ rubbing eyes/ eat without washing hands with soap and water. 
• Use hand sanitizer (>60% alcohol) in absence of soap and water

Other alternative possible preventive measures/ measure that boost immunity:

• Drinking a glass of Hot water everyday as a first drink in the morning
• Eating food/fruits that have high antioxidents such as Oranges, blueberry, amla(indian Gooseberry), ginger, and turmeric.

Treatment:

-For mild cases no treatment needed. For moderate cases observation and nasal oxygen is given.
- Serious cases need ventilation support and ICU level care.

1. Hydroxychloroquine :

Its the gold standerd medicine for treatment of malaria and its prophylaxis. In previous SARS outbreak it showed effective in laboratory study. Its in debate weather or not to use this drug for prophylaxis and treatment of covid19 (5). It goes in acidic environment/ in lysosomes and increase the pH. That's how it prevents virus replication and decrease inflammation. While arrythmia is one of its side effect which debates its use, its wide spread use in tropical county should allow them to consider it as a cheaper prophylactic alternative against Covid19.

As an inference, any person who have previously tolerated chloroquine (example:malaria prophylaxis/ other use) and doesn't have any heart problems, should take it as covid19 prophylaxis if they are health care workers or have Covid-19 positive family members. 

2. Antivirals:

a. Ramdesivir: used in Ebola virus: Showed efficacy in monkeys and later in human trials. Its broad spectrum antiviral against RNA viruses. Its more effective than lopinavir in decreasing lung pathology, improve pulmonary function and decreasing viral load.

b. Lopinavir/Ritonavir: 2-10% Decreased death rate in animal model.Not very effective

3. Streroids:
It is not shown to be beneficial in previous covid19 like infection like MERS, instead it showed to be harmful in critical patients. But, several recent study showed short course of steroid might be beneficial in moderate to severe cases of Covid 19.


Reference:

1.https://www1.nyc.gov/site/doh/covid/covid-19-data.page
2.https://www.worldometers.info/coronavirus/
3.https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/cases-in-us.html
4. MacIntyre CR, Chughtai AA. A rapid systematic review of the efficacy of face masks and respirators against coronaviruses and other respiratory transmissible viruses for the community, healthcare workers and sick patients [published online ahead of print, 2020 Apr 30]. Int J Nurs Stud. 2020;108:103629. doi:10.1016/j.ijnurstu.2020.103629
5. Pal A, Pawar A, Goswami K, Sharma P, Prasad R. Hydroxychloroquine and Covid-19: A Cellular and Molecular Biology Based Update [published online ahead of print, 2020 Jun 10]. Indian J Clin Biochem. 2020;1‐11. doi:10.1007/s12291-020-00900-x
6.Zhai P, Ding Y, Wu X, Long J, Zhong Y, Li Y. The epidemiology, diagnosis and treatment of COVID-19. Int J Antimicrob Agents. 2020;55(5):105955. doi:10.1016/j.ijantimicag.2020.105955
7. https://www.sciencemag.org/news/2020/04/how-does-coronavirus-kill-clinicians-trace-ferocious-rampage-through-body-brain-toes
8. Zemlin AE, Wiese OJ. Coronavirus disease 2019 (COVID-19) and the renin-angiotensin system: A closer look at angiotensin-converting enzyme 2 (ACE2) [published online ahead of print, 2020 Jun 2]. Ann Clin Biochem. 2020;4563220928361. doi:10.1177/0004563220928361
9. https://health.clevelandclinic.org/heres-the-damage-coronavirus-covid-19-can-do-to-your-lungs/