Here is the full list of all 16 The Infecting 3 achievements.
Finished Custom Survival Chapter 1
Complete Campaign
Shoot for the first time in Campaign
Beat the Lambda Trials Chapter 1
Reload for the first time in Campaign
Finished Custom Survival Chapter 2
Beat the Lambda Trials Chapter 2
Start Custom Survival Chapter 2: The Lambda Transaction
Kill 32,000 Enemies
Kill 64,000 Enemies
Take a Life
Kill 1,024,000 Enemies
Kill 48,064,000 Enemies
Kill 3 Enemies, you are going down a dark path
Complete Be the Zombie Chapter 1