The vampire myths comes from many differnt countries and many differnt ages you probably know  that there are many different versions of vampires like folklore or modern fiction and the modern vampire type appears often in books, TV and movies and their weaknesses are also very different.  

The virus called vampirism can in many ways it depends on what story you hear or what movie you are watching or what book you read what I heard is to be bitten, drink a vampire's blood or both ways at the same time  at the same time, or a blood transfusion,witchcraft,and it takes some days before you are fully transformed 

 Vampire weaknesses   i've heard about 

 A VAMPIRE CAN'T ENTER  A HOME  WITHOUT AN INVITATION  so you are save in your home 

CRUCIFIX used for protection. vampires can't look at a crucifix  without getting hurt 

HOLY WATERholy water acid for vampire the skin burn  by a toch og holy water 

SILVERsilver can kill vampires and it burns on their skin

A VAMPIRE IS A 

GARLICgarlic is like poison  for vampires 

SUNLIGHTwhen the sunlight hits the vampire  it burns up literally

STAKE  just drive a stake through the heart

HOLY BIBLE you just quote from the bible

FIRE 

MIRRORyou kan use this to identify a vampire because  vampire don't have any reflexion 

the combination of the human species and the vampire species is called Dhampir or hybrid because a combination of species is called hybrid and dhampir means only a combination of the vampire species and the human species