A History of Vaccines and How they Combat Disease

2020-03-31T18:13:55-07:00 February 28th, 2020|Book Review, Science and Society|

By Vishwanath Prathikanti, Political Science ‘23

Author’s note: The anti-vaccination movement has recently gained traction with many families across the nation and I wanted to tackle the idea of anti-vaccination and where it came from. I also wanted to see if there was any credit due to the anti-vaccinators and see if there was any truth to the idea that more vaccinations might be bad.

 

In April 2019, public health officials declared a measles outbreak in Los Angeles. To many, this sounded almost absurd; measles was eradicated in the United States in 2000 [4]. The outbreak highlighted the severity of a movement that many had declared irrelevant: the anti-vaccination movement. In light of this event, many had to question: what is the anti-vaccination movement? When did it begin? Is there any truth to the movement?

To understand the anti-vaccination movement, one must first understand vaccines and their history. Centers for Disease Control and Prevention (CDC) defines a vaccination as, “a product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease.” [1]. The human immune system uses white blood cells to fight infections in the body; specifically, there are three types of white blood cells that work together to fight infections: macrophages, B-lymphocytes and T-lymphocytes [2]. When a cell becomes infected or dies, it releases a chemical that attracts macrophages, which will engulf and degrade the cell. If the cell was damaged or died due to a virus or bacteria, the macrophage will leave behind antigens, which are recognized by the immune system as harmful [10]. When the immune system recognizes the antigens, B-lymphocytes will produce antibodies to attack the antigens and T-lymphocytes will attack cells in the body that have been infected by the identified antigen. After the infection is dealt with, the immune system will create memory cells that act immediately if the body encounters the same germ again. Vaccines work by imitating an infection; they do not cause illness but they will stimulate the production of T-lymphocytes, B-lymphocytes and memory cells to fight the disease in the future. Most vaccines require multiple doses to ensure full immunity, and how frequent these dosages are required depends on the vaccine [2]. 

Our knowledge of vaccines has not always been as vast as it is today. Evidence suggests that the earliest form of inoculation was in China during the late 1600s when emperor K’ang Hsi had his children inoculated after surviving smallpox (the process involved grinding smallpox scabs and inhaling them) [5]. The practice of vaccination has grown considerably since then, becoming vastly popular in the West by the 17th century. In 1853, Britain passed a law that made it mandatory for citizens to receive a smallpox vaccination and in 1855, Massachusetts passed the first U.S. law mandating vaccination for smallpox, allowing vaccinations to grow and develop. 

In the late 20th century, research on the negative effects of vaccines started to emerge. A 1995 study published in The Lancet linked the measles-mumps-rubella (MMR) vaccine with bowel disease. Wakefield, a gastroenterologist and researcher in the study, went on to further speculate that persistent infection with the vaccine caused disruption of the intestinal tissue that could lead to autism. This led to the study that would capture the attention of parents for decades to come. In 1998, Wakefield and his colleagues published a case series study in which, out of 12 children who had recently been administered their MMR vaccine, eight had the measles virus in their digestive system and were demonstrating symptoms for autism. Wakefield then went on to claim that the combined vaccination led to this, and advocated instead to adopt single-antigen vaccinations as opposed to combined MMR vaccines [3]. He did not, however, list how he came to this conclusion, saying “the combined measles, mumps, and rubella vaccine (rather than monovalent measles vaccine) has been implicated” [3].

The link between autism and the MMR vaccination was studied intensively over the next few years, and no reputable study ever found a similar link. Additionally, a study published in The Journal of Pediatrics, while acknowledging a slightly lower than average antibody count when the combined vaccination was employed, stated that there was no significant reason why single antigen vaccinations should be favored over combined vaccinations. The lower antibody count was deemed irrelevant in light of the fact that failure of the vaccine was extremely rare in fully immunized children [7]. In 2010, The Lancet formally retracted the paper, and three months later, Britain’s General Medical Council banned Wakefield from practicing medicine in Britain. Finally, in 2011, it was revealed that Wakefield had falsified most of his data; in his study, he reported eight children developed symptoms of autism when in reality, there were at most two cases. In addition, two of the children had developmental delays that were not mentioned in the final published work [3].

Despite the study being completely discredited by the scientific community, the damage to society had been done; after the Wakefield paper was published, vaccination rates dropped below 50 percent in some parts of London. Luckily, immunization rates drastically rose since then, with over 90 percent in the UK vaccinated in 2013, with BBC declaring a “universal recovery” [8]. Although vaccination rates are high, the US still faces about 60 cases of the measles every year, caused by international travelers who carry the disease [9]. While the spread of misinformation due to the Wakefield paper has mostly subsided, its legacy continues keeping a minority of children in the US unvaccinated and susceptible to antiquated and preventable diseases.

 

References

  1. Centers for Disease Control and Prevention “Immunization: the basics” https://www.cdc.gov/vaccines/vac-gen/imz-basics.htm
  2. Centers for Disease Control and Prevention “Understanding how vaccines work” https://www.cdc.gov/vaccines/hcp/conversations/downloads/vacsafe-understand-color-office.pdf
  3. History of Vaccines “Do vaccines cause autism?” https://www.historyofvaccines.org/content/articles/do-vaccines-cause-autism
  4. Centers for Disease Control and Prevention “History of measles”  https://www.cdc.gov/measles/about/history.html
  5. History of Vaccines “All timelines overview” https://www.historyofvaccines.org/timeline#EVT_1 
  6. Wakefield A, et al. RETRACTED:—Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. Lancet. 1998; 351(9103): 637-641. https://www.thelancet.com/action/showPdf?pii=S0140-6736%2897%2911096-0
  7. Heinz J. Schmitt, et al. “Primary vaccination of infants with diphtheria-tetanus-acellular pertussis–hepatitis B virus– inactivated polio virus and Haemophilus influenzae type b vaccines given as either separate or mixed injections.” The Journal of Pediatrics. 1999. https://www.sciencedirect.com/science/article/pii/S0022347600260885
  8. BBC “Measles outbreak in maps and graphics” 2013. https://www.bbc.com/news/health-22277186
  9. NPR “Fifteen Years After A Vaccine Scare, A Measles Epidemic” 2013. https://www.npr.org/sections/health-shots/2013/05/21/185801259/fifteen-years-after-a-vaccine-scare-a-measles-epidemic
  10. Arizona State University “Macrophages” https://askabiologist.asu.edu/macrophage