Viral load is how much your own body makes more viruses that then circulate in your own body.

The virus inserts mRNA into your cells by binding to ACE2 receptors (which vary depending on persons). Thus someone with many ACE2 receptors "receive" much more virus. Once mRNA is in the cytoplasm it then then replicates and transferred to ribosomes which pump out more viruses. The virus then are exported outside the cell to infect more. The amount circulating your system is the viral load.

Keeping away from others will not drastically affect this number.

Each person will vary on how they can prevent this from happening depending on their own unique immune systems.

The mRNA is NOT changing. I just ran a nucleotide comparison to the last sequenced RNA structure done in April and compared it to the first one done in China in December by using the BLAST RNA sequence comparison which available to the general public.