Vaccines are the Victims of Their Own Success?
Published September 1, 2018 | Opinion
successful in defeating infectious diseases that people forget how bad things were before vaccines. In a recent BMJ opinion piece, Giovanni Rezza, MD of Italy’s National Institute of Health explained:
Vaccines are the victims of their own success. Thanks to them, vaccine preventable diseases have declined or even disappeared, but this can lead to the perception that these infections are of a low risk, causing complacency, which is a factor in vaccine hesitancy and refusal.1Paul Offit, MD, who co-invented the RotaTeq pentavalent rotarvirus vaccine produced by Merck & Co., has repeated this explanation countless times in his lectures, interviews and articles. Earlier this year when he was awarded the Albert B. Sabin Gold Medal for his work on RotaTeq, Dr. Offit stated:
We have accomplished so much, discovering and introducing several vaccines that have reshaped the world as we know it, but vaccines will always be a victim of their own success. As once-common diseases disappear, it is increasingly important to stand as vaccine champions.2In a New York Post article, Offit was quoted: “Vaccines are a victim of their own success. People aren’t afraid of the diseases. They don’t see them.’’3 Another Offit quote in SELF magazine underscores this idea that people have been spoiled by the success of vaccines… “People aren’t scared of these diseases anymore because they don’t see them. This tells you we’ve been so successful that we’ve largely eliminated the disease and all memory of the disease.”4
In another variation of this theme, Offit adds a warning… “I think vaccines become less compelling now that we don’t see the diseases that vaccines prevent. In some ways they’re a victim of their own success. But if we lower our guard these diseases will come back.”5 In other words, vaccines have apparently been successful in conquering diseases, but the battle is never fully won. We must be prepared for permanent warfare. The enemy is always at the door.
Of course, the idea that vaccines are a victim of their own success is based on one very big assumption—that they were, in fact, the sole or primary cause of the decline in reports of infectious diseases during the late 20th century. It is primarily that assumption that has made vaccination the “medical sacrament corresponding to baptism.”6 7
But what if that assumption is false?
In a 1999 report by the Centers for Disease Control and Prevention (CDC), the control of many infectious diseases that were circulating during the 19th and early 20th centuries is attributed to a number of factors. The first factor the CDC lists is sanitation and hygiene. According to the CDC:
The 19th century shift in population from country to city that accompanied industrialization and immigration led to overcrowding in poor housing served by inadequate or nonexistent public water supplies and waste-disposal systems. These conditions resulted in repeated outbreaks of cholera, dysentery, TB, typhoid fever, influenza, yellow fever, and malaria.Others factors the CDC lists as contributing to infectious disease control include vaccination, antibiotics and other antimicrobial medicines, and technological advances in detecting and monitoring infectious diseases such as serologic testing, viral isolation and tissue culture, and molecular techniques.8
By 1900, however, the incidence of many of these diseases had begun to decline because of public health improvements, implementation of which continued into the 20th century. Local, state, and federal efforts to improve sanitation and hygiene reinforced the concept of collective “public health” action (e.g., to prevent infection by providing clean drinking water). By 1900, 40 of the 45 states had established health departments. The first county health departments were established in 1908. From the 1930s through the 1950s, state and local health departments made substantial progress in disease prevention activities, including sewage disposal, water treatment, food safety, organized solid waste disposal, and public education about hygienic practices (e.g., foodhandling and handwashing). Chlorination and other treatments of drinking water began in the early 1900s and became widespread public health practices, further decreasing the incidence of waterborne diseases. The incidence of TB also declined as improvements in housing reduced crowding and TB-control programs were initiated. In 1900, 194 of every 100,000 U.S. residents died from TB; most were residents of urban areas. In 1940 (before the introduction of antibiotic therapy), TB remained a leading cause of death, but the crude death rate had decreased to 46 per 100,000 persons.
Animal and pest control also contributed to disease reduction. Nationally sponsored, state-coordinated vaccination and animal-control programs eliminated dog-to-dog transmission of rabies. Malaria, once endemic throughout the southeastern United States, was reduced to negligible levels by the late 1940s; regional mosquito-control programs played an important role in these efforts. Plague also diminished; the U.S. Marine Hospital Service (which later became the Public Health Service) led quarantine and ship inspection activities and rodent and vector-control operations. The last major rat-associated outbreak of plague in the United States occurred during 1924-1925 in Los Angeles. This outbreak included the last identified instance of human-to-human transmission of plague (through inhalation of infectious respiratory droplets from coughing patients) in this country.8
The CDC apparently does not recognize vaccination as either the sole or primary cause of the decline in the morbidity and mortality of a number of infectious diseases. At best, vaccination is considered a contributing factor. Most of the infectious diseases for which physicians like Offit and Rezza like to credit vaccines for conquering were already in decline before the vaccines were introduced. This was certainly true for polio and some researchers believe it was true for other childhood infectious diseases, as well.9 10 11 12 13 14 15
Contrary to popular belief, the smallpox vaccine was not the “silver bullet” that can be solely credited with eradicating smallpox. It was more due to the strategy of surveillance and containment (quarantine) adopted by the World Health Organization (WHO) in the 1960s. CDC epidemiologist Donald Henderson, MD, who directed the international effort to eradicate smallpox from 1967 to 1977, referred to this strategy as the “single-most important component of the present global [smallpox] eradication effort.”16
Interestingly, the strategy was not a novel one. It had been successfully implemented in Leicester, England nearly a century earlier after the city had suffered a severe smallpox outbreak in 1872 despite having a highly vaccinated population due to mandatory vaccination laws. Brian Bystrianyk and Suzanne Humphries, MD write that after that outbreak the people of Leicester, “voted out of power their town government, and replaced it with one which created a smallpox safety system: laws were passed which made vaccination voluntary, established a rapid notification and quarantine system, including specially trained personnel and comfortable quarantine facilities for anyone exposed to the index (initial) case.”16 17
The strategy came to be known as the “Leicester Method.”16 18 That’s what beat smallpox.
So no, the whole “vaccines are victims of their own success” spiel doesn’t wash.Vaccination is not the only—or arguably even the primary—reason that a number of infectious disease that used to have a high mortality rate have waned over time, especially in developed countries. All you have to do is read a little history to understand that the decline in the morbidity and mortality of infectious disease has been a much more multifaceted process that has more to do with economic development, higher living standards and containment than anything else.
Referenc
No comments:
Post a Comment