Why HIV succeeded where other zoonotic viruses failed

Zoonotic diseases vector medical poster, infection transmission from animals to humans. [iStockphoto]

If HIV and Ebola both began as zoonotic diseases, why did one evolve into a global sexually transmitted epidemic while the other remains primarily a disease spread through contact with infected body fluids? According to Dr Moses Masika, Consultant Infectious Disease Physician and Medical Microbiologist, the answer begins long before a virus reaches its first human host. It starts with biology.

There are thousands of viruses circulating in wildlife around the world. Most never infect humans. Even when they do, many fail to survive beyond the first infected person because they cannot effectively enter human cells or reproduce inside them. Only a tiny fraction successfully adapts.