Intradermal hepatitis B immunization with yeast-derived vaccine: serological response by sex and age.

The efficacy and acceptability of yeast-derived recombinant hepatitis B vaccine given by the intradermal route was investigated in 221 health care volunteers. Two hundred and sixteen received a full course of three doses of vaccine. Only one subject was withdrawn because of a significant adverse reaction (psoriasis). The vaccine stimulated an antibody response in 81%. The response to the vaccine was better in women than in men (87% compared with 71%, p = 0.007) and in women below the age of 40 years compared with older women (94% compared with 76%, p = 0.01). For men the response showed a sequential decline with age for each decade (90% responders from age 29 or less, 72% aged 30-39 and 65% aged 40 or more, p = 0.04). Retrospective enquiry showed that over 90% had found the intradermal route acceptable and 59% would prefer vaccine by the intradermal route in preference to intramuscular notwithstanding local reactions. Although the seroconversion rate was of a high order in younger women the antibody titres were not high with only 9 of 215 recipients developing titres greater than 1000 mIU/ml, a level which could be expected to ensure prolonged immunity. A fourth intradermal dose of vaccine given to 60 volunteers who had shown a low response (less than 38 mIU/ml) or no serological response to a three-dose course stimulated a good booster effect (to 150-600 mIU/ml) in only 5 (8%).

Problems in the disinfection of class 1 microbiology safety cabinets.

Microbiology safety cabinet disinfection procedures using formaldehyde have been tested. Tubercle bacilli were killed by concentrations of formaldehyde obtained by heating commercial formalin irrespective of whether the bacilli were in the cabinet free space or above the prefilters. However, Bacillus stearothermophilus spore papers for for the testing of low temperature steam/formaldehyde sterilisers were almost never sterilised and a strain of Staphylococcus epidermidis (NCTC 7944) showed a resistance intermediate between the B stearothermophilus spores and the tubercle bacilli. Tests using a vaccine strain of poliovirus type 3 indicated a considerable degree of resistance of the virus to the action of formaldehyde. No such resistance was demonstrated by vaccinia virus or echovirus 14. Chemical and biological evidence is presented which indicates that filter paper discs are an unsuitable carrier material for a challenge organism in testing the efficiency of any formaldehyde sterilising process. Recommendations are made towards developing a satisfactory test procedure.

Recombinant WRL 105 strain live attenuated influenza vaccine. Immunogenicity, reactivity, and transmissibility.

The immunogenicity, reactivity, and transmissibility of recombinant WRL 105 (H3N2) (A/Okuda/57XA/Finland/4/74) strain live attenuated influenza virus vaccine were studied in adult male volunteers in a residential community in rural England. Thirteen volunteers received a single dose of 10(7.0) E.I.D.50 recombinant WRL 105 vaccine administered as nose drops, and twelve volunteers received placebo. Nine (82%) of eleven volunteers with initial antibody titres of less than or equal to 1/96 showed a significant antibody response to vaccination, but there was no evidence of transmission of vaccine virus to those who received placebo. The incidence and nature of reactions were similar in those who received vaccine and placebo. The vaccine was shown to confer protection against natural infection with a strain exhibition antigenic characteristics equivalent to those of A/Scotland/840/74.