Epidemiology And Today's Deadliest Diseases
What is an 'epidemic'?
An "epidemic" refers to an unusual occurrence of disease in the population. In common thinking, we might consider an epidemic to be a dramatic occurrence of disease, with numerous cases that occur worldwide or in a population. However, this is not necessarily true. It depends specifically on the type of disease that we are talking about. In some cases, an epidemic can be represented by a single case of a disease that has been long absent from the population, an example being small pox, which has been eradicated from the world. Or an epidemic can be one or two cases of a disease that is uncommon, such as the plague. These diseases are potentially a great concern to public health authorities because they could spread rapidly in the population. In other cases, we are simply talking about an unusual or greater occurrence of a disease that exists normally. For example if we speak about an epidemic of influenza, then the centres for disease control maintains statistics that shows seasonal transitional distribution of influenza, and when we observe a major departure from what the normal expectancy is, then it can be said that an epidemic is occurring.
What is a 'pandemic'?
A pandemic refers to an epidemic that occurs on a worldwide scale. So there is concern, for example, about Avian Influenza as a condition that could produce a pandemic. Or, many forms of Influenza that could be occurring on a pandemic scale. It means that the disease has jumped its national boundaries wherever it occurs, and then has spread to many other countries and is affecting many countries at the same time. A really good example of this is the 1918 Influenza pandemic that affected not only the United States but the entire world, and was an important cause of mortality worldwide.
What are the top three causes of death in the US?
In the United States, the top three causes of death are coronary heart diseases, diseases of the heart, cancer and then cerebrovascular disease.
What's the most common form of cancer in the US?
In the United States, the most common form of cancer for both men and women is lung cancer. Among women, breast cancer was formerly a more common form of cancer, but apparently as women are smoking with greater frequency the rates of lung cancer are increasing among women.
Are the causes of death in the US different from the rest of the world?
In the United States, coronary heart disease is the leading cause of mortality. If we look at less developed areas of the world, infectious diseases are often the leading cause of mortality, although in some developing areas, coronary heart disease, cancer and other chronic diseases of this type are coming to the forefront. In many other developed parts of the world, cancer is the leading cause of mortality and not coronary heart disease.
Which country in the world has the highest life expectancy?
The country in the world that has the highest life expectancy is Andorra, which is a small country located near Spain. Another country that has a high life expectancy is Japan.
Where does the US rank in the world in terms of life expectancy?
In comparison to other developed countries the United States falls behind in terms of life expectancy. It is not among the top ten in the world and in fact is among the lower countries in the world. The life expectancy levels is close to that of Cuba; which is our neighbor nearby.
Which diseases are of the highest concern to epidemiologists today?
One of the conditions of concern to epidemiologists is the avian influenza. The concern is that the avian influenza could invade the human population and mutate into a form that can be spread from one person to another, and then be spread across the world as a pandemic. Fortunately, that hasn't happened yet, but it is something that epidemiologists are concerned about. Another major condition of concern to epidemiologists is HIV AIDS. In the United States there has been control over HIV AIDS or a degree of control; however, it is becoming a major problem in some sub-groups of the United States population. And also, worldwide it is a problem of great significance. For example, in some of the countries of Africa, there is a very high morality rate due to HIV and AIDS, and epidemiologists are concerned about the impact that this will have on the population.
What is the 'influenza virus' or 'the flu'?
The term flu refers to influenza, and influenza is caused by a specific type of virus. The virus mutates every year so that's why it's necessary to have a new flu shot every year. The flu produces different symptoms, in many cases it depends on the type of variety that we're talking about, in most people it would produce fairly mild, self-limiting illness. However, in people who are vulnerable, who have reduced immune status, influenza can be a significant cause of mortality.
How do epidemiologists keep track of the flu?
Epidemiologists keep track of the flu through the national surveillance system that is used by the Centers for Disease Control and Prevention. They have collected over the years detailed information about seasonal trends. Flu is grouped with pneumonia and influenza mortality. They collect continuing statistics and then note whether or not the occurrence of mortality exceeds the expected levels during a particular time or season of the year.
