14. COVID and Science

Question 1

Why are some people asymptomatic?

Answer 1

(1) Pre-exposure: presence of T cells from other coronaviruses such as the common cold, providing some degree of immunity
(2) Vaccination: some observational studies recognized a 28% reduction in COVID infection risk through recent pneumonia vaccines and 43% through polio vaccines. Causation yet to be determined.
(3) Personal characteristics: younger age, fit and healthy, absence of co-morbidities mean immune system is stronger to deal with symptoms

Question 2

Age

Answer 2

(1) Immune system weakens according to age. This reduces ability to fight off pathogen.
(2) Old age associated with medical conditions such as heart disease, diabetes, both of which are medium risk categories which can exacerbate symptoms

Question 3

Diabetes

3.7x more likely to have a critical case of COVID

Answer 3

(1) Health conditions associated with diabetes e.g. cardiovascular and kidney conditions. Flu and pneumonia are more common and serious in older individuals with type 2 diabetes
(2) Chronic inflammation: increased coagulation activity, immune response impairment and potential direct pancreatic damage by SARSCOV2

Question 4

Heart disease and hypertension

Answer 4

Virus depletes body’s supply of oxygen so heart must work harder to pump oxygenated blood throughout the body

Question 5

Smokers

Answer 5

Damage tissues of respiratory system and triggers chronic inflammation

Question 6

Obesity

Answer 6

(1) Obesity = risk factor for severe infection
(2) Reduced lung capacity
(3) Increased inflammation in human body = harmful immune response