Other various Hib disease and vaccine issues:
This is about the old Hib polysaccharide vaccine (a vaccine very different from the Hib vaccine used at present, the Hib conjugate vaccine) that was used from the late 1980′s untill 1990. It was effective in Finland, but had an effectiveness as low as negative 58% in the United States.
http://jama.ama-assn.org/cgi/content/abstract/260/10/1423
We evaluated the efficacy of Haemophilus b polysaccharide vaccine in children in Minnesota using a case-control study. The vaccine became available in Minnesota in August 1985. During the subsequent 28 months, 88 cases of invasive H influenzae type b disease were identified in children 24 to 71 months of age, the group targeted for vaccination. Of the 88 cases, 36 (41%) occurred in vaccinated children. Fifty-eight (33%) of 176 controls were vaccinated during a similar period. The vaccine’s protective efficacy for children with any history of vaccination was -58% (95% confidence interval = -204% to 18%). The vaccine’s protective efficacy for children who were most likely to be protected by vaccination was -55% (95% confidence interval = -238% to 29%). Our results indicate that vaccination with Haemophilus b polysaccharide vaccine had no effect in preventing H influenzae type b disease in Minnesota children
Interestingly, there is an old pneumococcal polysaccharide vaccine (different from Prevnar, but still given to older folks over 50) which is also ineffective.