A seemingly innocent question that once confounded an array of people, resulting in much controversy and dispute, yet now in contemporary times, this question is considered by the vast majority to be ludicrous and nonsensical; no more then mere ineffable trash, with evidence being non-existent, however this has never been the case.
Evidence supporting the existence of vampires has always existed in our society, since the spawning of these creatures. They have simply been well-hidden from the public as have many things… (aliens/UFOs and werewolves)
One obvious piece of evidence would be the fact that there are descriptions of vampires from an array of existing and pre-existing cultures across the world. Drawings and written descriptions of human-like creatures that would draw blood from their victims, with uncanny strength, speed, elongated fangs, varying skin pigmentation, aversion to sunlight and allergic to garlic. The underlying, rudimentary characteristics as described above all correlate and remain consistent amongst different cultures. There are descriptions of vampires extending across the globe from places such as Africa to India to China.
The existence of vampires in an array of cultures is an obvious indication that there is something similar if not identical to the creatures described in our world.
Eye testaments are few and limited to hundreds and seldom thousands each year overall with encounters described also having strong correlations with one and another. Overall, the evidence supporting the existence of vampires is sparse, yet effectively strong. Eye testaments still dwell within the hundreds and even if a strong percentage of these encounters are the result of hoaxes, conjectures of the mind, etc… the remaining portion accumulated by time, is still substantial itself. The existence of vampires in cultures also suggest that they were (if not are) abundant and thriving.
Anyway, if we are to accept the existence of vampires, then there are a set of explanations suggesting why they are seldom seen, however before we can acknowledge these we need to first accept the different species or types of vampires and their characteristics:
(The following set of explanations have been intentionally adjusted to be brief, succinct and concise and were derived from authentic sources.)
1. True vampires: These were the vampires that were first, supposedly spawned from the ruins of hells by Lucifer himself, sent forth to bestow evil and suffering on the earth. They were strong once, but god punished them and caused them to suffer, making them sensitive to light and garlic, as well as diminishing their strength and longevity. These vampires are the true ones, whose blood hasn't been tainted with the human gene and are pure. There are few of them left in our modern society and most of them are in stasis (long periods of hibernation extending from years to centuries). They have differing skin pigmentation to us and have retractable, elongated teeth, aversion to the sun and are sensitive to garlic. They also may have pointed ears and slant eyes.
2. Modern vampires: These vampires are a hybrid amalgamation of vampires and humans, sharing varying characteristics as a consequence of the different gene ratios. In most modern vampires, the vampire gene is weak, having been tainted by the human genes and compared to a true vampire, they are almost nothing. The most common characteristics include: retractable elongated teeth, slight aversion to light and possibly an aversion to garlic. They are almost indistinguishable from humans. There are different species of the common modern vampire.
3. Psychic vampires: These vampires drain energy rather then blood and are homo sapiens biologically speaking.
4. Sanguinarians: Humans who simply drink blood…
Vampires reproduce in the same means as we do, and fawn offspring with shared DNA through the union of male and female parts, however they were also able to fawn offspring through biting them, however these offspring didn't share common DNA with the vampire that bit them. The transferal of the vampiric virus was a technique that became abandoned as the number of true vampires dwindled. The vampiric virus still exists in true vampires (but they are undergoing stasis) and would have undergone mutations, making it weaker, whilst remaining in the host. (The strength of true vampires has dwindled dramatically)
The stereotype notions surrounding the vampires were once authentic yet can't be appropriately applied to vampires today (mainly modern), i.e. driving a wooden stake through their heart was a biblical technique introduced by a priest whom received a message from god, when his monastery was being attacked at night and his brothers slaughtered by vampires, that the wooden stake would drive their souls back to hell.
There are various sub-species of modern vampires (Homo Wampyrus) too, i.e. Homo Wampyrus Draco.
Anyway, now that the general background information on vampires has been covered, a list of reasons why these vampires aren't frequently seen in public will subsequently follow:
1. True vampires aren't seen because they are all enduring stasis and are hidden in dark places where sunlight can't penetrate or is at an effective minimal.
2. Modern vampires are virtually indistinguishable physically from humans.
3. Vampire attacks are infrequent because most vampires obtain blood through friends or from donors. Government agencies, supposedly support, them too by providing sustenance.
4. Most vampire sightings are from professionally trained vampire hunters (often working in distinction to governments, thereby maintaining effective secrecy). They are also experts at readily distinguishing vampires from humans.
5. MOST VAMPIRES DON'T EVEN KNOW IF THEY ARE VAMPIRES! (The aversion to sun is natural and coincides with many diseases and the craving for blood may be seen as a mental disorder, whilst the agility and grace and any other athletic traits may be considered natural. Modern vampires, may not even possess athletic qualities, depending upon the strength of the vampiric gene residing in them)
In general, vampires do exist and have always existed. Historical records of vampires are present and sightings/encounters do exist, but biological variations may not necessarily be picked up due to the technology we have present being inferior to what is required. The overall view of vampires being strange, eccentric creatures is fallacious. They can simply be viewed as people with different needs and functions to us. (the terms true vampires and modern vampires are often used interchangeably due to the lack of true vampires present)