Variation is when different genes are expressed but variation can also be due to

Crossing over (genetic recombination) and random segregation during meiosis can result in the production of new alleles or new combinations of alleles. Furthermore, random fertilization also contributes to variation.

this disease is :

* endemic (present in a defined area that is a village)

* a bacterial infection (treated with antibiotic)

* communicable by contact (by the hands)

manu-porterage is the most common mode of transmission, it transmits germs from one individual to another via the hands. this concerns infections of exogenous origin.

endemic disease, or endemic disease, refers to a disease that is constantly present in a given population, often tied to a specific geographic origin, as opposed to a pandemic that is not a sporadic disease.

antibiotics are molecules that have the property of killing (bactericidal) or limiting the spread (bacteriostatic) of bacteria.