Bubonic Plague Resurfaces in Arizona Emergency Room

**Yersinia pestis** is not an organization but a bacterium responsible for causing the plague, a zoonotic disease with a long history. It is a Gram-negative coccobacillus, discovered by French bacteriologist Alexandre Yersin in 1894 during a plague epidemic in Hong Kong[7]. The bacterium is transmitted primarily through the bites of infected fleas, which act as vectors between rodents and humans[1][5]. ### History and Evolution - **Origin**: *Yersinia pestis* evolved from *Yersinia pseudotuberculosis*, an enteric pathogen, through gene acquisition and genome reduction about 6,000 years ago[8]. - **Historical Impact**: The bacterium has been linked to three major pandemics, starting in 541 AD, and most notably, the Black Death in Europe during the Middle Ages[1][7]. ### Key Aspects - **Transmission and Disease Forms**: Plague manifests in three main forms: bubonic, pneumonic, and septicemic. Bubonic plague is the most common form, characterized by swollen lymph nodes or buboes[1][5]. - **Virulence Factors**: The bacterium uses various virulence factors, including plasmids like pCD1, pPCP1, and pMT1, which encode proteins essential for its pathogenicity[2][8]. ### Current Status - **Global Presence**: Today, *Yersinia pestis* is found in natural foci in the Americas, Africa, and Eurasia, with cases reported mainly in impoverished African countries and parts of the United States[1][5]. - **Control Measures**: Antibiotic treatment is effective if administered promptly, and public health measures focus on surveillance and vector control[3][5]. ### Notable Aspects - **Vaccination and Treatment**: Early antibiotic treatment and vaccination efforts have significantly reduced plague mortality rates[7]. - **Evolution

The **United States** is a federal republic and a global superpower, playing a leading role in economics, military strength, technology, and governance. It is a nation of approximately 348 million people as of 2025, characterized by its diverse population and dynamic economy[8][6]. Founded in 1776 following independence from British rule, the U.S. rapidly evolved into a major world power, especially after World War II, when its technological and economic investments solidified its global dominance[4]. Today, it remains the world’s preeminent military power, with 76% of Americans recognizing this status, while about half view it as the leading economic power globally, though China is seen as a rising competitor[2][3]. The U.S. government operates through a complex system that manages federal finances, taxation, social welfare programs, and trade policies. Recent legislative changes, such as the 2017 Tax Cuts and Jobs Act and the 2025 One Big Beautiful Bill Act, have shaped the tax landscape to influence economic growth, labor markets, and federal revenue[1]. Despite challenges like rising federal deficits projected to reach 6.9% of GDP by 2027, consumer spending remains resilient, and business investment is expected to grow steadily in 2025[5]. In governance, the U.S. is rated "Free" with a score of 84/100 by Freedom House, though concerns about democratic erosion and partisan conflicts persist[6]. Public trust and satisfaction with government services fluctuate, reflecting ongoing debates about policy effectiveness and institutional competence[7]. Technologically, the U.S. maintains a critical edge, underpinning its economic and geopolitical power. Experts warn, however, that technological dominance is not guaranteed indefinitely, emphasizing the need for adaptive policies and international cooperation to sustain leadership in innovation and global affairs[4]. Overall, the United States remains a pivotal force in global business, technology, and politics, balancing historic strengths with contemporary challenges in

The World Health Organization (WHO) is a specialized agency of the United Nations, established in 1948, with a mandate to promote global health, coordinate international responses to public health threats, and set standards for health policies and interventions[2]. Headquartered in Geneva, Switzerland, WHO operates in over 150 countries, working with governments, NGOs, and other partners to advance health equity, strengthen health systems, and respond to health emergencies. ## What WHO Does WHO’s core activities include monitoring global health trends, setting international health standards, providing technical assistance to countries, and serving as a forum for scientific and policy discussions on health issues[2]. The organization publishes influential reports such as the annual **World Health Statistics**, which tracks progress toward Sustainable Development Goals (SDGs) and provides a global “health report card”[1][8]. WHO also maintains the Model List of Essential Medicines, guiding countries on which drugs are most critical for public health[7]. In addition, WHO leads global campaigns on issues ranging from infectious disease eradication to noncommunicable diseases (NCDs), maternal and child health, and health emergencies[2][6]. ## History and Key Achievements WHO’s history is marked by landmark achievements, including the eradication of smallpox, near-eradication of polio, and the development of an Ebola vaccine[2]. The organization played a pivotal role in responding to the COVID-19 pandemic, coordinating global research, vaccine distribution, and public health guidance. In May 2025, WHO member states adopted the world’s first **Pandemic Agreement**, a historic step to improve international coordination and equity in future health crises[4]. WHO also spearheads initiatives like the Triple Billion Targets (healthier lives, universal health coverage, and protection from health emergencies) and technical policy packages targeting tobacco, alcohol, salt, and trans fat reduction[1][2]. ## Current Status and Notable Aspects WHO is currently implementing its **Fou