10 Most Formidable Diseases
Modern medicine entered a period of rapid progress during the turn of the 20th century. More advances have been made in the last half of this century than in all of modern history. As we enter the 21st century, we continue to make spectacular progress at an amazing rate but it still can’t seem to keep up with our medical needs. However far medicine has come, there are still some diseases that have planted a firm foothold on our lives, so much so that they have survived the centuries and remained incurable. The following is a list of these diseases.
Influenza is the technical name for one of the most common and most contagious diseases, the flu. It is a viral illness of the respiratory tract that is characterized by a high temperature, sore throat, running nose, headache, dry cough, and muscle pain.
Several strains of orthomyxoviruses, namely types A, B, and C, are the causes of influenza. Symptoms of all three types are generally the same but are completely unrelated antigenically. This means that when you get infected by one type, it does not make you immune to the other types. Type A influenza cause great epidemics; type B cause relatively smaller and more localized outbreaks. Type C influenza viruses do not infect humans.
The viruses undergo constant and rapid changes, making the development of influenza vaccines a challenge. Influenza not only infects humans but also pigs, horses, and other mammals, as well as some birds. The virus has the unique ability to undergo major evolutionary change in its genetic makeup that it becomes a completely new subtype to which very few or none at all are immune. There have been cases of these new types of the virus being able to jump from one species to another, like the Avian flu in 1997, and the current H1N1 Swine Flu.
So far, influenza continues to remain as a formidable adversary.
Acquired Immune Deficiency Syndrome or AIDS
AIDS is an immune system disease caused by the human immunodeficiency virus, or HIV. The virus is transmitted through blood or body secretions such as semen. People with AIDS are unable to fight infections because the virus slowly attacks and destroys some types of white blood cells. AIDS is the final stage of HIV infection and patients usually die from secondary causes, like pneumonia or cancer.
The disease originated from Africa, where there was an HIV and AIDS epidemic in the 1980s. Contributing factors to the worldwide spread of the disease include increasing urbanization in Africa, increased international travel, changing sexual mores, and intravenous drug use. Since 1981, around 20 million people have died from AIDS and about 3 million people still die each year from the disease. Additionally, 38 million are infected with HIV as reported by a report from the UN in 2004, and 5 million more get infected every year.
Commonly known as lupus, this is a chronic, autoimmune disease that causes inflammation of connective tissue, specifically the skin, joints, and internal organs. There are three main types: discoid, systemic, and drug-induced lupus.
Discoid lupus is largely confined to the skin and is characterized by the appearance of red rashes with grayish brown scales on the face, neck, and scalp. Ten percent of people infected with discoid lupus develop the more serious systemic lupus.
Systemic lupus is more common and more severe. It can affect any part of the body, most commonly the skin, kidneys, joints, heart, brain, gastrointestinal tract, and membrane linings of organs. The symptomatic rash resembles that of discoid lupus. Symptoms of lupus appear intermittently and may mimic symptoms of other disorders, so diagnosis can be difficult.
Diabetes is a disease of the pancreas characterized by the organ’s inability to sufficiently produce or appropriately respond to insulin, which results in the inability to maintain proper blood sugar levels.
Two major forms of the disease are Type I diabetes, or insulin-dependent diabetes mellitus (IDDM), and Type II diabetes, or non-insulin-dependent diabetes mellitus (NIDDM). Type I diabetes is also called juvenile-onset diabetes because it usually develops during childhood. This type of diabetes is a form of autoimmune disorder in which the immune system produces antibodies that destroys the cells which produces insulin. People with Type I diabetes are dependent on insulin injections because their body can no longer produce insulin.
Type II diabetes is also called adult-onset diabetes, occurring in people who are 40 years and older. This type is characterized by the insufficient production of insulin by the pancreas or inability of the body to respond to insulin secretions. It has a hereditary nature and affects people who are obese. To manage blood sugar levels, treatment is through controlled diet and exercise, insulin injections, or oral medications.
The Common Cold
The common cold is a viral infection of the respiratory system characterized by sneezing, nasal congestion, coughing, and headaches. There are more than 100 agents which cause the common cold, these include parainfluenza, influenza, respiratory syncytial viruses, reoviruses, and rhinoviruses.
The term was coined because it was incorrectly believed that exposure to a cold environment directly causes the sickness. However, a cold environment, chilled wet feet, or drafts do not cause the common cold, but is rather caught from exposure to other infected people. The cold virus can be carried and communicated by people who have not experienced the symptoms themselves. Communicability starts even before the symptoms appear and reaches its peak during the symptomatic phase. Incubation is between one to four days.
Asthma is a chronic disease of the respiratory system, often caused by allergies, which triggers inflammation of the airways. Symptoms include coughing, difficulty in breathing, and a tight feeling in the chest, with severity ranging from mild to life-threatening. Allergens may include dust mites, animal dander, pollen, air pollution, cigarette smoke, weather conditions, medications, and physical exertion. Stress is also a contributing factor.
Half of all asthma cases occur in children and boys are more affected than girls. Childhood asthma is usually inherited, with susceptibility to certain allergens. Among adults, asthma affects men and women equally and usually develops in response to allergens, as well as viral infections, medication, and exercise. Asthma in adults may also be linked to nasal polyps or sinusitis.
Cancer is characterized by the uncontrolled growth of abnormal cells in the body which destroy healthy tissue. There are more than 100 types, depending on the location of the growth. This disease is a major cause of sickness and death worldwide, affecting one in every three persons in developed countries. Cancer has been around for hundreds of years and cancer treatment has greatly improved since the mid-20th century. Effective treatment involves a combination of timely and accurate diagnosis, selective surgery, and therapy through radiation and drugs. In developed countries, advancements in cancer treatments have resulted in decreased deaths.
Significant advances in cell biology, genetics, and biotechnology have contributed greatly to a better understanding of cancer development, which translates into further progress in the prevention, diagnosis, and treatment of the disease.
The Ebola virus originated from the Ebola River in the Democratic Republic of Congo in South Africa. It was first identified in 1976, in Zaire and Sudan, which resulted in hundreds of deaths. A second outbreak happened again in Zaire in 1995.
The Ebola virus is a lethal virus that is characterized by massive hemorrhaging and destruction of internal tissues. It is transmitted by blood and other body fluids and has a high fatality rate, between 50% and 90%. Aside from humans, this virus has also killed large numbers of gorillas and chimpanzees in some parts of Africa.
The Marburg virus is closely related to the Ebola virus and takes its name from its place of origin, Marburg, Germany. It was first discovered in 1967 when laboratory workers, after coming into contact with body parts of African monkeys, became infected. Another related virus is the Ebola Reston, which infected monkeys in a laboratory in Reston, Virginia, but is not fatal to humans.
Polio is the common name of poliomyelitis and is an infection that can sometimes cause temporary or permanent paralysis. It is also called infantile paralysis because it mostly affects children, normally those under the age of five, although the virus also affects young adults.
At its worst, the polio virus enters the nervous system and infects the nerves that control the muscles. This may then result in the paralysis of the limbs, throat, or chest. It can become more dangerous and even fatal when it enters the brain. More often than not, though, the virus only causes general symptoms, including fever, nausea, fatigue, and muscle pain and spasms.
More than 90 percent of infections produce no noticeable symptoms at all or only mild ones that last for a few days. Between five to ten percent display the general symptoms described above. And less than one percent of those infected actually suffers from paralysis.
Polio was one of the most dreaded diseases in the mid-20th century, infecting hundreds of thousands of children every year. During that time, there was no cure for the virus, but since the 1960s, polio vaccination has almost completely eradicated the virus from the world. It is now only found in third world countries in Africa and South Asia. Each year, 1,000 – 2,000 children in these countries are still paralyzed by polio.
Creutzfeldt-Jakob disease, or CJD, is a rare degenerative brain disease, a form of human spongiform encephalopathy, characterized by vague psychiatric or behavioral changes, followed by progressive dementia that is accompanied by abnormal vision and loss of muscle control. CJD also causes a characteristic sponge-like pattern of brain degeneration that leaves brain tissue filled with holes.
Worldwide, CJD occurs at an incidence of one person in a million but occurrence is much higher in certain populations, like Libyan Jews. The disease commonly infects adults between the ages of 40 and 70 and occurs equally between men and women. The disease was named after German neurologists Hans Gerhard Creutzfeldt and Alfons Maria Jakob, who first discovered it in the 1920s.
There is no known treatment for CJD and it has a high fatality rate, usually within a year of the start of symptoms.