Question 1. A and C (Yes and Maybe; more, below)
Question 2. C. Specific IgG and IgM testing
Most pediatric neurologists in 1955 would have recognized the cause of this child’s slow deterioration, subacute sclerosing panencephalitis (SSPE), a rare complication of measles occurring in about 1 in 10,000 measles cases. It typically develops 6 to 15 years after infection and is thought to be persistent infection in the CNS with an aberrant viral gene expression. It is diagnosed by elevated IgG antibodies in the blood and CSF along with the characteristic EEG. His measles IgM antibodies were negative, as is expected with SSPE. Epidemiologic studies suggest SSPE is more common following infections in younger children and, interestingly, in milder initial measles infections.
Measles vaccine is not usually given until a child’s first birthday since circulating maternal measles antibody may interfere with an immune response. This child clearly was not protected from a dose of MMR given at 8 months of age. MMR vaccine has to be kept frozen and given within 30 minutes after reconstitution or thawing. Proper vaccine storage is presumably more of a problem in third world countries. At the same time, in high risk situations the vaccine can be given to children as young as 6 months of age but this dose does not count toward the two-dose series currently recommended.
Theoretically, since the MMR shot is a live attenuated vaccine it might be able to cause SSPE but if it does, it does so at a much lower rate than natural measles disease. The number of annual cases has plummeted in the US since the introduction of the MMR vaccine suggesting a protective effect from the vaccine.
Was this child’s disease vaccine-preventable?
I think the best answer is "yes," but an argument could be made for “maybe.” If a child contracts a vaccine preventable disease before the usual age of vaccination, then in a sense the disease was not vaccine preventable since the child wasn’t yet eligible for that vaccine. The report of this case in the MMWR did not mention the exact age in months when this unfortunate child developed measles, just that he was a year of age. If he contracted measles shortly after turning one year of age then he may have been too young to get his next dose of MMR. I wonder if he had gotten a second dose at age 12 months if this tragedy could have been averted. The reason, however, that the best answer is "Yes, this was vaccine preventable" is that this young boy caught the measles from a person most likely unvaccinated.
There is no reason why measles cannot follow smallpox, becoming a disease now eradicated from the world. No animal reservoir exists. You only get the measles after being exposed to another human with measles.
Liko J, Guzman-Cottrill JA, Cieslak PR. Notes from the Field: Subacute sclerosing panencephalitis death — Oregon, 2015. MMWR Morb Mortal Wkly Rep. 2016;65:10–11.
Krugman S, Ward R. Infectious Diseases of Children and Adults. 5th ed. Saint Louis, MO: The C. V. Mosby Company; 1973.
Note: This older Krugman, Ward infectious disease textbook was published at a time when many cases of SSPE were still popping up since the MMR vaccine was first approved in 1971.