Infectious agent: Typhoid fever is caused by the bacterium Salmonella enterica serotype Typhi.

Disease type: Typhoid fever is classified as a bacterial infectious disease/ a waterborne disease. Basically it is not zoonotic and it is defined as a disorder caused by bacteria that can spread directly or indirectly from one host to another.

-It spread to Europe, North America, Africa, South Asia, and South America.

b. Timeline:

-Ancient records: Diseases that presented similarily to Typhoid were described in antiquity.

-1700s-1800s: Repeated Typhoid fever outbreaks occurred in Europe and North America due to contaminated water.

-1800-early 1900s: Spread through colonization and ship travel to Africa, Asia, and South American colonies.

-Mid 1900s: The introduction of antibiotics and improved water/sewage treatment systems mostly erradicate Typhoid in the U.S., Canada, and western European countries.

-Present day: Typhoid fever remains endemic in third world countries that struggle with having clean water such as places in South Asia, Sub-Saharan Africa, and Southeast Asia.

c. Historically, records show that the fatality rate of people infected with Typhoid fever was around 10-20%. However, before the 20th century Typhoid was difficult to differenciate from other fevers, so we do not know how many people globally were infected with it over centuries.

-Modern estimates say that around 9-20 million people are infected with Typhoid Fever each year, leading to 100,000-150,000 deaths a year in countries where it is still endemic in the modern day.

Overtime, the virulence of Typhoid fever has declined due to antibioltics and public health initiatives. Effective medical treatment as well as modern sanitation effortss has caused fatality rates to drop to less than 1% in the 21st century. However, the virulence of Typhoid fever is slowly rising with antibiotic resistant strains of the bacteria.

Historically, Typhoid fever has been handled through early diagnosis through testing, antibiotics, and improving sanitation methods. Once Salmonella Typhi was identified as the cause of the sickness healthcare providers began isolating sick patients and emphasizing handwashing and clean water access publicly. Ovetime, the health care community began contact tracing in order to control outbreaks.

b. What medical advances were used in combatting the disease?

Antibiotics were the most important medical advance made for Typhoid Fever. Chloramphenicol was introduced in 1948 and dramatically reduced typhoid lethality. Later on ampicillin, fluoroquinolones, and other antibiotic medications were developed and were standard treatments. Vaccines were also developed to prevent Typhoid in high-risk regions of the world. The Ty21a oral live-attenuated vaccine as well as newer typhoid conugate vaccines produced strong and long lasting immunity to the bacteria.

c.Were any new technologies applied to this disease? What were they?

Yes, typhoid conjugate vaccines, molecular PCR tests, and water sanitation technologies all applied to this disease. Typhoid conjugate vaccines use carrier proteins to help the immune system form long-term protection, they are regarded as a huge breakthrough in disease control worldwide. Molecular PCR tests allowed for a quicker and more accurate detection of the Salmonella Typhi bacteria, especially in areas where traditional stool/blood cultures are difficult. Development of water and sanitation technology like filtration systems, chlorine dispensers, and municipal water treatment played a huge role in reducing transmission through contaminated water.

Leadership response depended on region but public health initiatives usually focused on sanitation and quarantine measures. Governments implemented water chlorination and improved sewage systems. Public health campaigns emphasized handwashing and hygenic ways to handle food. In countries like the United States and Canada major Typhoid control measures appeared in the early 1900s starting with chlorinating the water in large cities. The United States was particularly focused on erradicating the Typhoid fever epidemic. Public health officials would enforce quarantine and keep infected individuals in hospitals, demonstated in the "Typhoid Mary" case where an asymptomatic carrier of the disease was quarantined for almost 30 years.

b. Were any innovative initiatives used in combatting the disease? What were they?

While chlorinating municipal water systems was probably the biggest initiative that drastically reduced typhoid transmission, replacing old contaminated sewage pipelines with more modern sewage treatment was an important aspect of limiting large outbreaks of the disease. Carrier-tracing programs where asymptomatic carriers of the disease were tracked were also a major step in public health along with the development and distribution of typhoid vaccines.

c. What could leadership have done better in response to this disease?

The largest ethical issue with the leadership response was of course how public health officials treated carriers of the disease. The U.S. government focused almost entirely on forced isolation as seen in the Typhoid Mary case. Mary Mallon was forced to quarantine against her will for 30 years! This situation was a catalyst for development of public health laws that emphasized education-based interventions instead of imprisonment. There also should've been stronger international cooperation between governments around the world. The UK had had sand filtration of municipal water supplies since the late 1800s, global coordination on water treatment standards could have reduced transmission in other countries during this time as well. There are also still developing regions in the world where typhoid outbreaks are common, this shows a lack of global support on educational initiatives and vaccinations.

Typhoid fever was one of those revoluntionary diseases of the 20th century in terms of societal impact. The disease exposed how sanitation and water infrastructure had historically been failing to protect people from disease. How class and socioeconomic status affected peoples suffering from disease was also more widely highlighted with Typhoid. Sociologically, many wealthy people began associating Typhoid with poverty, creating stigma even when terrible infrastructure was actually to blame. Typhoid Mary of course hugely impacted society, with science and public health recognizing asymptomatic carriers widely due to her.

b. Did any society behaviors change?

Due to things like Typhoid Mary, there began to be an increased focus on hygiene, such as handwashing and safe food-handling practices. Public health ideas became more relevant and well known in society after the Typhoid epidemic. New public health initiatives also taught people that contaminated water spread disease, leading to people beginning to boil their water and water infrastructure getting a major over haul.

c. Did society “learn” from the physical effect of the disease?

I would say yes, the physical effect of Typhoid Fever did teach society a lot of hard lessons. Outbreaks pushed cities to update to modern sewage systems and actually enforce water quality standards. There is also the aformentioned creation of modern public health policies born from a better understanding epidemiology. Knowledge of asymptomatic carriers, mandatory reporting of infectious disease numbers, and prevention based healthcare all were lessons learned by society from Typhoid Fever.