The type of immunity that is present at the time of birth in humans is innate immunity.The two ways it can be accomplished are:
1.Certain types of leucocytes(WBCs) like neutrophils, monocytes and natural killer(lymphocytes) in the blood and marcophages in tissues can engulf microbes, viruses and cellular debris,etc.
2.Mucus secreted by mucous membrane traps the microorganisms and immobilize them.The skin is the physical barrier of the body.Its outer tough layer prevents the entry of bacteria and viruses.