Most often vaccination technology is traced back to 1796 when Edward Jenner had success in England protecting people against smallpox. However, it wasn't until the 20th century that vaccines really made an impact on the public's health. Beginning early in the century, and accelerating after WWII, the great microbial scourges were de-clawed in a stunning triumph of scientific ingenuity. The incidence of smallpox, polio, measles, diphtheria, whooping cough, mumps, and rubella all declined by about 100% in the 100 years ending in 2000. This was important in the dramatic increase of U.S. life expectancy from about 42 years in 1900 to about 78 today. People survived these threats to children and lived to almost complete their genetic potential for life expectancy. Ironically, this allowed our bodies to live long enough to develop chronic diseases of aging. Nevertheless, no one should pine for the bad old days when at least one in ten infants, and many older children perished, mostly from infections.
In recent years there has been a persistent myth in the popular media that vaccines are the cause of autism. Let's be clear: no valid science exists to link vaccination with autism. This is another case where people have trouble with uncertainty, but look for something to blame when unknown is less satisfying.
Some of the interesting new vaccination innovations include the HPV vaccine, which protects young people against papilloma virus infections, and subsequently, protects women against cervical cancer. This is a fairly new vaccine, and some people feel there was too much hurry bringing the vaccine to market. There is no evidence of danger, but the effectiveness may be less than was hoped. Another new vaccine is one for shingles, and recommended for people over the age of 60, when shingles becomes quite common. Because shingles is rarely life threatening, or even severe enough to require hospitalization, some insurance companies are limiting coverage. Their attitude is "Quit being such a wimp about it. You'll get over it and be just fine." Perhaps as the vaccine grows in popularity the price will drop.
There is research being done on a vaccine to prevent smoking initiation and discourage continued smoking. The mechanism is to modify the nicotine molecule so that it is not able to enter the brain and stimulate the receptors which make the drug so reinforcing. In this case, smoking would not provide any benefit, leading youth not to go beyond experimenting and confirmed smokers to extinguish their habits. Stay tuned. Were this technology ever to reach the market, it would be great news for millions of smokers. There is parallel research going on to harness vaccine manipulation of the endocrine system, making food less reinforcing. At this point, there is only preliminary evidence that such an approach could actually work; it is probably many years away in any case.
The two elephants in the room for traditional vaccine applications are HIV/AIDS and malaria. These two diseases result in about 2 million and 850,000 deaths each year on planet earth. We don't have exact statistics because the regions of the world where they wreak the most havoc, such as sub-Saharan Africa, have inadequate systems to monitor incidence and causes of death. The good news is that there is research to develop vaccines for each of these infections, and there is some optimism that in the not too distant future there will be success. In terms of public health impact, a Nobel Prize will be in order.
Unfortunately, in spite of the tragic toll taken by HIV and malaria, any vaccines would be considered "orphan drugs." The lion's share of pharmaceutical research is done in the private sector, and this is one of the most profitable enterprises. This industry without doubt is responsible for true "wonder" drugs which have improved the lives of millions of patients. However, a market-driven drug industry means there is a whole category of drugs, so called "orphans" which because their market potential is limited, are never brought to market. For this reason there are illness for which we have drug solutions, but because they are rare, there is no business incentive to make the investments needed to bring them to market. HIV and malaria are in this category. The largest market for any vaccines would be in places where most of the patients live-places where people can't pay, and even if they could, it is a one time payment. Companies are most interested in drugs which people take on a daily basis for years at a time. Vaccines are usually not like that. It is likely that HIV and malaria vaccine research will have to be largely subsidized by governments and humanitarian organizations, and their distribution will not be sponsored by corporations.
Life without vaccines would be unfathomable. There is reason to expect that they will make life even better, promoting health for all in the future.
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