“Designing Tomorrow’s Vaccines” is a fascinating assessment of the success of vaccines as well as a look into the what future vaccines may accomplish (NEJM 2013; 368: 551-60).
First, I like the quote from Thomas Jefferson noted in the article:
“I avail myself of this occasion of rendering you a portion of the tribute of gratitude due to you from the whole human family. Medicine has never before produced any single improvement of such utility…mankind can never forget that you have lived. Future nations will know by history only that the loathsome small-pox has existed and by you has been extirpated.” Letter to Edward Jenner (May 14, 1805).
Jefferson’s enthusiasm was not without merit. “In the 20th century alone, smallpox claimed an estimated 375 million lives.” Yet, “since 1978, not a single person has died from smallpox.” Unfortunately, at this time, every year “more than 1.5 million children (3 per minute) die from vaccine-preventable diseases.”
Previous success in the U.S: Comparison of the estimated number of cases per year in the 20th century with the number of deaths in the year 2002 from the same diseases:
- Poliomyelitis: 1.63 million vs 0
- Diptheria: 17.6 million vs 0
- Measles: 5.03 million vs 36
- Pertusis: 1.47 million vs 6632
- Rubella: 4.77 million vs 20
- Smallpox: 4.81 million vs 0
Despite these advances, vaccines have “yet to realize their full potential.” Effective vaccines are needed for malaria, HIV, and tuberculosis. Vaccines for influenza which rely on 50-year-old technology need to be improved.
So how can this be achieved?
- Improved knowledge of atomic structure/structural biology has provided new insights into neutralizing antibodies along with specific antibody reactions. This can counter immune evasion by targeting highly conserved regions
- Millions of gene sequences encoding antibodies within a single individual can be analyzed to improve vaccine design
- Genomewide sequencing of microbes has improved selection of vaccine targets
- Improvements in delivery systems, like using viruslike particles or nanoparticles; alternatively, gene-based delivery of vaccines is feasible
- Recombinant techniques has allowed a shift from egg-based methods
What is not on the horizon — a vaccine for the half-truths that permeate the discussion.