Prophylactic or Therapeutic Vaccine Options
A potential leprosy vaccine can be either prophylactic (preexposure) or therapeutic (postexposure). Dr. Tom Gillis, Chief of the National Hansen’s Disease Programs Lab Research, remarks that it is not necessarily easier to create either version of the vaccine. However, in America, because of the low incidence of leprosy, it makes much more sense to focus on a therapeutic vaccine to administer only to those who are actually affected by the disease.
Pros of a Prophylactic Vaccine:
- An effective prophylactic vaccine could break transmission by giving individuals immediate as well as extended protection from infection of leprosy.
- A prophylactic vaccine should also help stop the emergence of drug resistance since it would protect against both drug-susceptible and drug-resistant strains.
- Can be given to all newborns as the BCG vaccine is to provide protective immunity against future infection.
Pros of a Therapeutic Vaccine:
- A therapeutic vaccine could improve a patient’s response to multidrug therapy by possibly reducing the occurrence of relapse cases.
- A therapeutic vaccine can be given in conjunction with multidrug therapy for people already infected with leprosy, therefore targeting only those who actually have the disease and saving money (may be more helpful for areas where leprosy is not a major problem, where it does not make sense to vaccinate everyone).
- Easier to test because you can target subjects easier (people who already have leprosy and are in the process of treatment).
- Could speed treatment and recovery for those already infected with M.leprae.