Schaefer BA, et al. – Aim was to confirm immunogenicity of Diphtheria Tetanus acellular Pertussis (DTaP) vaccines administered subcutaneous (SQ) to individuals <6 years old with haemophilia. In a pilot study of Haemophilia patients, SQ administration of diphtheria and tetanus vaccination appeared to be immunogenic. Findings supported this practice as the standard of care for this population.

Methods

• Among patients evaluated at the Haemophilia Treatment Centre between 2015-2016, a retrospective and prospective pilot study of tetanus and diphtheria antibody titres, was conducted.
• The eligibility criteria were met by children with haemophilia who had received three to four doses of DTaP containing vaccine administered SQ.

Results

• Inclusion criteria were fulfilled by eight children.
• In addition, the mean age at the time of diphtheria and tetanus antibody testing was 21.1±17.8 months.
• A positive antibody titre to both antigens was developed in all children who received SQ diphtheria and tetanus.
• No statistically significant difference was observed in distribution of titre values.
• Among SQ vaccinated subjects, the average time between the last dose of vaccine and antibody testing was 6.6±3.9 months.
• It was found that minor injection site reactions were common with SQ vaccines.