Infectious Disease History and Public Health Measures Lecture

These flashcards review key people, public-health milestones, disease trends, and concepts discussed in the lecture on the history and control of infectious diseases.

Who is credited with developing the first vaccine and what disease did it prevent?

Edward Jenner; his cowpox inoculation protected against smallpox.

What observation about milkmaids led Jenner to study cowpox?

Milkmaids who caught mild cowpox did not later contract deadly smallpox, suggesting cross-protection.

How did Jenner test his cowpox theory and what virus did he use?

He inoculated an 8-year-old boy with material from cowpox lesions (vaccinia virus) and later exposed him to smallpox; the child never developed smallpox.

Why did the Academy of Sciences initially dismiss Jenner’s paper?

He had only one experimental subject; they wanted 100 cases for statistical significance.

Describe the traditional Chinese practice of variolation against smallpox.

Dried, powdered material scraped from smallpox pustules was blown/placed into a person’s body (often the nose or mouth) to induce a mild infection that conferred immunity.

Which antiseptic did Joseph Lister spray on surgical wounds, and what was the outcome?

Aerosolized phenol (carbolic acid); surgical-site infections dropped from ~45 % to ~15 %.

How did early 20th-century food regulation begin in the United States?

Exposés like Upton Sinclair’s novel “The Jungle” prompted meat-packing reforms and the creation of state health departments to oversee food safety.

What two public-health measures were identified as the biggest steps in reducing U.S. infectious-disease deaths?

(1) Forty state health departments regulating the food supply and (2) chlorination of municipal water.

Name the three leading causes of death in 1900 America.

Pneumonia, tuberculosis, and diarrhea/enteritis (including dysentery).

Roughly what fraction of all deaths did tuberculosis account for around 1900?

Nearly 25 % of total deaths.

Why have heart disease, cancer, and stroke replaced infections as top killers today?

People now live long enough for age-related diseases to manifest because early death from infections has been greatly reduced.

Which disease became the leading cause of death for 25- to 44-year-olds in the United States during the late 1980s and early 1990s?

HIV/AIDS.

Define an emerging infectious disease (EID).

A disease first recognized or significantly increasing in incidence within the last approximately 35 years.

How did pathogenic E. coli O157:H7 arise?

E. coli O104:H4 acquired Shiga-toxin genes from Shigella, turning a mild diarrheal strain into one that can cause bloody dysentery.

What is the clinical difference between diarrhea and dysentery?

Dysentery involves visible blood in the stool, indicating intestinal tissue damage and higher risk of systemic infection.

What does MDR tuberculosis mean?

Mycobacterium tuberculosis strains that are resistant to at least two first-line anti-TB drugs.

Give one reason malaria risk is re-emerging in parts of the United States.

Resurgence of Anopheles mosquitoes (e.g., after DDT use ended and climate/environment changed) enabling local malaria transmission.

List two human behaviors that accelerate the spread of emerging infections.

Rapid global travel and expansion of housing into wildlife habitats (e.g., suburbs in tick-rich areas).

Why do some people underestimate the danger of vaccine-preventable diseases today?

Modern patients rarely witness dramatic outcomes (iron lungs, mass measles wards), so they misjudge the severity and view vaccines as unnecessary or unsafe.

What is the Human Microbiome Project (HMP) and how does it differ from the Human Genome Project?

HMP seeks to sequence and analyze all microbial species living on/in humans, whereas the Human Genome Project sequenced human DNA.

Why should dramatic health claims about the gut microbiome be interpreted cautiously?

Early studies may use extreme doses, small samples, or speculative links; media often exaggerates preliminary findings.

Before antibiotics and vaccines, which measures produced the largest drop in infectious-disease mortality?

Sanitation, safe food handling, clean (chlorinated) water, and hygienic medical practices like Lister’s antiseptic surgery.