Floyd S. Markham

Immunizing properties of live attenuated measles virus

Summary Early clinical trials indicate that it is possible to immunize children with live attenuated measles virus. The susceptible subjects develop either no symptoms at all or a modified measles with fever, leukopenia, and a faint eruption. Koplik spots are uncommon. These children have no catarrhal symptoms and do not appear toxic. All of the susceptible children developed a significant titer of neutralizing antibodies. No complications occurred in any of our cases. The urgent need of a measles vaccine is stressed, and there are indications that measles immunization as a routine procedure may not be too distant.

Simplified Indirect Complement-Fixation Test Applied to Newcastle Disease Immune Avian Serum

Summary 1. A simplified procedure for the indirect complement-fixation test is described. 2. The serums of 59 Newcastle disease immune chickens were tested by the simplified indirect complement-fixation and by the hem-agglutination-inhibition tests. 3. Good general agreement was observed between the titers obtained by the two methods.

Stabilizing Action of Glycerine on Hemagglutination of Egg-Adapted Mumps, Newcastle Disease and Influenza Viruses

Conclusions (1) Experimental observations based on the behavior of two strains of mumps virus having hemagglutinins of markedly different stability show that the addition of glycerin has a marked stabilizing action on the nonagglutinating antigen. Without glycerine, at 37°C the H strain of mumps virus in buffered saline containing 0.1% formalin, loses its hemagglutinating activity overnight and the E strain in 3 to 4 weeks. In contrast, the H strain in 50 per cent glycerine suspension, also containing 0.1 formalin, maintained useable titers for 2 to 3 weeks at 37°C, and under the same conditions the E strain showed little or no loss of activity at the end of 16 weeks. (2) Glycerine concentrations as low as 10% markedly enhanced the stability of the E strain while the stability of hemagglutinating activity of the H strain was dependent to a much greater degree upon an increased concentration of glycerine. (3) The hemagglutinating activity of antigens prepared from suspensions of Newcastle disease virus and influenza virus (PR8) was similarly stabilized by the addition of 50% glycerine.

Prospects for measles immunization with reference to the relationship between distemper and measles viruses

Summary The results of several cross-immunologic experiments in various animal species and in tissue culture failed to confirm the relationship between measles and distemper viruses that has been reported by others, dimming the hope that distemper virus might be used as an effective prophylactic against measles. In contrast, vaccination of children with attenuated measles virus promptly induced measles antibodies, even when the concentration of virus administered was only 6 TCD 50 . In most instances, vaccination evoked mild clinical symptoms similar to those in gamma globulin-modified measles, the most prominent of these being fever that ranged from 38° to 40° C. and lasted one or two days. Rash also was recorded in a number of children, but Koplik spots and catarrhal signs were unusual. Affected children did not appear to be toxic or acutely ill; this was the case even in those who had significantly elevated temperatures. No virus was recovered, either from nasopharyngeal swabs taken on the seventh, ninth, and eleventh days after vaccination or from third-day blood samples, and no cases of secondary measles occurred in either institutionalized children or those living with their families. Questions about the vaccine still to be answered concern the duration of the immunity provided, the possibility of postvaccination encephalitis, and the ability of vaccinees to transmit the infection. Answers depend on the gradual and careful extension of trials in susceptible children.