References

Vitamin C:

https://www.consultdranderson.com/ 
​
Zinc:

Systematic review and meta-analysis shows a specific micronutrient profile in people with Down Syndrome: Lower blood calcium, selenium and zinc, higher red blood cell copper and zinc, and higher salivary calcium and sodium

Zn2+ Inhibits Coronavirus and Arterivirus RNA Polymerase Activity In Vitro and Zinc Ionophores Block the Replication of These Viruses in Cell Culture
​
Vitamin D

Determinants of vitamin d levels in children and adolescents with down syndrome.

Vitamin D for prevention of respiratory tract infections: A systematic review and meta-analysis

Lymphopenia:

Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study  - Table 1 shows the lab findings that include a low lymphocyte count.

Intrinsic abnormalities of lymphocyte counts in children with down syndrome.

Glucose metabolism in lymphocytes is a regulated process with significant effects on immune cell function and survival

Impaired brain glucose metabolism in patients with Down syndrome.

Histamine:

Mast cells contribute to coronavirus-induced inflammation: new anti-inflammatory strategy.

Impact of polyphenols on mast cells with special emphasis on the effect of quercetin and luteolin

Quercetin, Inflammation and Immunity