Blood injury and injection (BII) phobia is a subtype of specific phobias. It is the unique phobia in which fainting occurs. The purpose of this study was to report the age of onset of BII phobia. Period of persistence of fear in BII phobic patients, the percentage of inheritance from generation to generation and the percentage of BII phobic patients who suffer spontaneously were analysed. A survey was performed among five sample populations and a total of 3261 individuals were interviewed for blood injury and injection phobia using a semi-structured questionnaire according the DSM V. A significantly higher number of subjects who are suffering from BII phobia had a familial history of the same phobia. Patients were analysed for three groups, those having persistence of BII phobia from 1-10 years, >10-20 years and more than 20 years. It was found that 5.74±2.49 (% mean ±SD), 5.94 ±1.09 and 4.89±0.69 of BII phobic patients have persistence of fear related to this phobia within these three groups. The pedigree analysis of the families of BII phobic patients reveals that 61.1%, (SD±9.30) showing more than one family member with this phobia, 13.85% (SD±9.39) were discontinuous expressions and 25.02, SD ±5.46 were spontaneous expressions whose Phobia is considered due to environmental factors. The persistence of fear related to BII phobia shows that a greater number of populations suffering from BII phobia are completely living in fear of blood, injury and injection or their related ques which make them inept in daily life. Patients suffering from BII phobia continuously live in fear and anxiety which decreases their efficiency in daily activities. This is a public health issue which must be addressed to create the chance for patients of BII phobia to become the productive members of the society.

Keywords: Blood Injury Injection, Phobia, persistence, Inheritance