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Old vaccines and new vaccines explained

I am a strict constructionist on the necessity of vaccines. Since Edward Jenner produced a vaccine for smallpox in 1799, millions, perhaps billions of lives have been saved by vaccines. The search for new vaccines will never end because infectious organisms constantly evolve. Influenza viruses evolve to escape last year’s immune defenses. We have yet to master HIV with a vaccine. 

From the time of Edward Jenner, there has been resistance to vaccination.  Resistance to measles vaccine is currently high. I do not know the reason for this rejection of vaccines. Some people believe that the diseases we vaccinate against are not so bad. Others think that good parenting will protect their kids, or some vaccines are more dangerous than the disease they are designed to prevent, or worse, that the vaccines cause the disease. Some people are infuriated that government, through public health authorities, has control over their families. Some people feel that scientists and physicians condescend to them, which nobody likes.

Let me explain how to make a vaccine and show that it works. The first thing we must do with any infectious disease, whether Ebola, measles or anthrax, is to identify and purify a virus or bacteria that causes the disease under question. The rules for establishing this connection were worked out by the German bacteriologist Robert Koch in the 1880s. 

 

The second, third, and fourth vaccines came 80 years after Jenner’s smallpox vaccine (this 80 years contains multitudes.) They were to counter chicken cholera, anthrax, and rabies — rabies being the first treatment of a feared human disease. Louis Pasteur and his students grew these pathological organisms, realized that they could weaken them, that the weakened forms could still provoke resistance, and that the animals or humans (in the case of rabies) would be protected against future infection. 

They knew nothing about the immune system — only that they could make animals resistant. It was neither simple nor safe to make and test these vaccines, but in doing it, they worked out the principles of microbiology that have been the foundation for infectious disease research ever since. They faced strong opposition, but Pasteur was a warrior and defended his new science fiercely.     

There followed, by the 1930s, vaccines to diphtheria, tetanus and whooping cough that were gradually administered across Europe and the United States with reductions in these diseases. In the 1950s, the polio vaccines (Salk and Sabin) became available and then in 1963, measles, followed by mumps and rubella. These are the familiar DPT and MMR vaccines.   

 

Let’s concentrate on measles. In 1963, there were about 500,000 cases of measles in American children. Almost every child got infected, but the virus was not (and is not) benign. Some infections led to complications, mostly encephalitis, and there were about 400 deaths. 

In 1963, a measles vaccine was developed and in a few years the disease disappeared in the United States and other countries, with only sporadic cases.  Now, with refusal to take the vaccine, hundreds of cases have appeared. According to the Centers for Disease Control, there were 880 cases from Jan. 1 to May 17 this year in the U.S., a large increase from 2018 when there were 372. Almost none of these patients had been vaccinated. 

The MMR vaccine also provides resistance to mumps and Rubella, and predictably, new cases have appeared. Mumps has its own set of complications, including sterility. Rubella causes birth defects. MMR does not cause autism, though that remains a fear among some parents. 

The pediatrician and infectious disease physician Paul Offit has made the point that a dreadful epidemic might convince people to vaccinate, but until then there may be little change. Still, it would be a shame to ignore evidence for the efficacy of the 20 vaccines we now give to children.

Could such a major epidemic erupt? Influenza or other respiratory virus is always a possibility. The H1N1 flu pandemic of 2009-2010 mercifully collapsed, unlike that of 1918-1919, which killed about 50 million people worldwide. For sheer terror consider the case of Ebola, which this column has covered extensively. (Go to www.tricornernews.com or and search for Richard Kessin Ebola.)

Two-thirds of Ebola victims die. We now have what appears to be an effective vaccine. For various reasons there is unlikely to be a large outbreak of Ebola in the United States, but if there were, my guess is that as Dr. Offit suggested, a lot of minds would change. 

Richard Kessin, PhD, is professor emeritus of pathology and cell biology at The Columbia University Irving Medical Center.  If you have a group that would like further explanations of infection and immunity or other biological subjects, he would be happy to come talk with you. Email him at Richard.Kessin@gmail.com.