Measles vaccines: follow up

Since last year when we discussed protection against measles with vaccines and gamma globulin,1 three vaccines have become available in Britain. All are ultimately derived from the Edmonston strain of virus: Mevilin-L (Glaxo) and Wellcovax (BW) are preparations of live attenuated virus, and Mesavac (Pfizer) is a formalin-killed virus. Clinical trials in Britain2 3 indicate that these vaccines give effective protection against measles. Mevilin-L and Wellcovax have not been directly compared, but seem to be about equal in effectiveness and in their liability to cause fever and other constitutional disturbance. The basic NHS cost of Wellcovax is marginally less (14/-) than that of Mevilin-L (14/3).

Immunity of Guinea-pigs to Diphtheria Toxin and its Effect upon the Offspring

1. A male guinea-pig which has received a single injection of a mixture of diphtheria toxin-antitoxin causing severe constitutional disturbance, may beget offspring of slightly lower resistance than normal to diphtheria toxin2. This effect is generally restricted to young born within twelve months after the injection of the father, being rarely noticed in the young of later litters.3. An increased susceptibility to diphtheria toxin is likewise observed in the offspring of male or female guinea-pigs which have received a large dose of horse serum. The greater susceptibility to diphtheria toxin of the young of male guinea-pigs which have been treated with toxin-antitoxin may therefore be non-specific in character.4. The injection of diphtheria toxin-antitoxin mixtures into guinea-pigs whether male or female reduces their rate of breeding and lowers the vitality of their young.5. These effects are most pronounced when the toxin-antitoxin mixture produces severe constitutional disturbance or contains excess of horse serum

Immunity of Guinea-Pigs to Diphtheria Toxin and its Effect upon the Offspring

(1) The young of parents both of which have been injected with an immunising mixture of diphtheria toxin and antitoxin, show immunity of the same order as that of young from similarly treated mothers and normal fathers.(2) The injection of certain foreign substances into a female guinea-pig appears to have a direct effect on the offspring in diminishing their resistance to diphtheria toxin, shown equally well by the young of mothers injected, (a) before the attainment of sexual maturity, (b) during pregnancy, and (c) after birth during the period of lactation.(3) A single injection of diphtheria toxin may give rise to a condition of active immunity (as tested by the resistance of the young) in guinea-pigs possessing hereditarily transmitted passive immunity. Should this injection of toxin give rise to great constitutional disturbance, the young may show lowered resistance, whereas, if it give rise to but slight constitutional disturbance, the young show a high degree of immunity. These effects appear to be accentuated if similar injections are repeated in the next generation.