epidemic disease

Examples of epidemic disease in the following topics:

• Disease Reservoirs and Epidemics

  • The natural reservoirs of some diseases still remain unknown.
  • In epidemiology, an epidemic occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected, based on recent experience.
  • Epidemics for certain diseases, such as influenza, are defined as reaching some defined increase in incidence above this baseline.
  • A few cases of a very rare disease may be classified as an epidemic, while many cases of a common disease (such as the common cold) would not.
  • An epidemic disease is not required to be contagious, and the term has been applied to West Nile fever.

• Disease in the New World

  • Rampant epidemic disease, to which the natives had no prior exposure or resistance, was one of the main causes of the massive population decline of the indigenous populations of the Americas.
  • The scope of the epidemics over the years was tremendous, killing millions of people—possibly in excess of 90% of the population in the hardest hit areas.
  • After the epidemics had already killed massive numbers of indigenous Americans, many newer European immigrants assumed that there had always been relatively few indigenous peoples.
  • The diseases brought to the New World proved to be exceptionally deadly to the indigenous populations, and the epidemics had very different effects in different regions of the Americas.
  • While epidemic disease was by far the leading cause of the population decline of the American indigenous peoples after 1492, there were other contributing factors--all of them related to European contact and colonization.

• Current Epidemics

  • An epidemic occurs when new cases of a disease, in a given human population, and during a given period, substantially exceed expectations.
  • In epidemiology, an epidemic occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected based on recent experience.
  • The declaration of an epidemic usually requires a good understanding of a baseline rate of incidence; epidemics for certain diseases, such as influenza, are defined as reaching some defined increase in incidence above this baseline.
  • A few cases of a very rare disease may be classified as an epidemic, while many cases of a common disease (such as the common cold) would not.
  • Modern transport contributes in spreading diseases faster.

• The Vocabulary Epidemiology

  • The distinction between "epidemic" and "endemic" was first drawn by Hippocrates, to distinguish between diseases that are "visited upon" a population (epidemic) from those that "reside within" a population (endemic).
  • A pandemic is an epidemic of infectious disease that has spread through human populations across a large region; for instance multiple continents, or even worldwide.
  • The term epidemiology is now widely applied to cover the description and causation of not only epidemic disease, but of disease in general, and even many non-disease health-related conditions, such as high blood pressure and obesity.
  • Thus, incidence conveys information about the risk of contracting the disease, whereas prevalence indicates how widespread the disease is.
  • Compare and contrast the following concepts: epidemic, endemic, pandemic; incidence vs prevalence; morbidity vs mortality; incubation, latency, acute, decline and convalescent periods

• Development of New Vaccines

  • New vaccines are being developed to control recent infectious disease epidemics and cancers.
  • Even in the poorest countries, immunizations have been able to achieve significant progress in disease control.
  • A number of new vaccines with major potential for controlling infectious diseases have just been licensed or are at advanced stages of development.
  • In addition to these efforts against global diseases, progress is being made on a vaccine for the regional menace posed by meningococcal meningitis serogroup A, which causes frequent epidemics and high death rates and disability in African countries south of the Sahara.
  • Describe how new vaccines are being developed to help eradicate several infectious global diseases

• Infectious Diseases Today and in the Developing World

  • Infectious diseases, also known as transmissible diseases or communicable diseases, are clinically evident illnesses resulting from the infection, presence and growth of pathogenic biological agents.
  • These pathogens are the cause of disease epidemics, in the sense that without the pathogen, no infectious epidemic occurs.
  • However, some infectious diseases remain a problem today.
  • The top three single agent/disease killers are HIV/AIDS, tuberculosis and malaria.
  • Assess the implications of infectious diseases in terms of health care and life expectancy of individuals

• Smallpox

  • Smallpox broke out in army camps in 1775 during an epidemic that lasted for most of the war.
  • The North American smallpox epidemic of 1775–1782, when the fatal infectious disease spread across the continent, coincided with the American Revolutionary War.
  • During Washington's siege of the city, the disease broke out among both Continental and British camps.
  • By 1779, the disease had spread to Mexico, where it would cause the deaths of tens of thousands.
  • Discuss the impact of the smallpox epidemic during the American Revolution.

• Poliomyelitis

  • Roosevelt is perhaps the most famous polio sufferer, though the late onset of the disease and symptoms brings the diagnosis into question.
  • Although major polio epidemics were unknown before the late 19th century, polio was one of the most dreaded childhood diseases of the 20th century.
  • Polio epidemics have crippled thousands of people, mostly young children; the disease has caused paralysis and death for much of human history.
  • Polio had existed for thousands of years quietly as an endemic pathogen until the 1880s, when major epidemics began to occur in Europe; soon after, widespread epidemics appeared in the United States.
  • Enhanced vaccination efforts led by the World Health Organization, UNICEF, and Rotary International could result in global eradication of the disease.

• Colonialism and the Spread of Diseases

  • Furthermore, sexual transmission of disease grew with colonization.
  • Encounters between explorers and populations in the rest of the world often introduced new diseases, which sometimes caused local epidemics of extraordinary virulence.
  • European colonization contributed to the spread of disease worldwide.
  • The sleeping sickness epidemic in Africa was arrested due to mobile teams systematically screening millions of people at risk.
  • Summarize the impact of European colonialism on the spread of infectious disease and beginnings of disease control

• Occurrence of a Disease

  • An occurrence of disease greater than would be expected at a particular time and place is called an outbreak.
  • Two linked cases of a rare infectious disease may be sufficient to constitute an outbreak.
  • Outbreaks may also refer to endemics that affect a particular place or group, epidemics that affect a region in a country or a group of countries, and pandemics that describe global disease outbreaks .
  • As described by the Centers for Disease Control and Prevention, these include the following:
  • Each has a distinctive epidemic curve, or histogram of case infections and deaths.