South African people are vaccinated with Yellow fever. First, SA is strict in the implementation proof of vaccination in travelers coming in the country. The vaccination card must show vaccination at least ten days prior to travel. This is to prevent reintroduction of the disease to SA people. Second, In the list of Center for Disease Control, South Africa is not included in the countries with an endemic Yellow fever which means that the disease is wiped out if not controlled through vaccination.
Answer:
Make sure everyone meets criteria.
Not taking supplements( As some may contain Vit D)
No tanning beds
make sure no one has a hypoactive response to vitamin d through whatever way. Injection, capsule, spray.
Check for genetic conditions or cancers like melanoma which indirectly affect vitamin d levels
Explanation:
These are some of the main things to look out for
Symbiosis is the relationship of 2 organisms. The 3 major types are commensalism, mutalism, and parasitism. Hope that this helps!