The most common diseases vary depending on where you live in the world. Many diseases still common in impoverished areas do not exist in developed countries. The most common diseases in the United States account for 7 out of 10 deaths each year, with about 133 million people suffering at least one chronic illness.
The common cold is a viral infection of the upper respiratory system with symptoms of a runny nose, itchy throat and sneezing. The National Institute of Allergy and Infectious Diseases reports that people in the United States suffer about 1 billion colds each year.
Anemia is the result of a decreased level of healthy red blood cells, or RBCs, that carry oxygen to all parts of the body. Causes for anemia include blood loss, destruction of RBCs or an inadequate production of RBCs. The Centers for Disease Control and Prevention reports that in 2006 there were 1.3 deaths from anemia out of 100,000 people in the United States.
Hepatitis B, a liver disease caused by the hepatitis B virus, or HBV, presents as acute or chronic illness. In about 5 percent of adults with an acute infection of HBV, the disease becomes chronic, according to the American Liver Foundation.
Children infected at birth have a 90 percent chance of developing chronic hepatitis B. Since hepatitis B often shows no symptoms, people may not know of the infection until blood is drawn for other conditions.
Periodontal disease, or gum disease, affects about 80 percent of adults in the United States, as reported by Medline Plus, a publication of the National Institutes of Health. Gingivitis, a common gum disease, causes the gums to bleed easily and become red and swollen. Infection sets in with gingivitis, if left untreated.
Lung cancer, the most common cause of cancer death in men and women, accounts for about 1/3 of cancer-related deaths in the United States every year, reports Cedars-Sinai.
Lung cancer is present as small cell or non-small cell cancer, with small cell the more aggressive of the two types. Non-small cell lung cancer has the higher cure rate, with as much as 80 percent success, depending on the size and if the cells are confined to the lung.
Diarrhea is a common health disease with symptoms of loose, watery stools and cramping.
Causes of diarrhea include bacteria such as Campylobacter, Shigella, E. coli and Salmonella; viruses including rotavirus, cytomegalovirus and herpes simplex virus; parasites such as Giardia lamblia; medications; food intolerance and bowel disorders.
The National Digestive Diseases Information Clearinghouse reports the average adult in the United States will experience acute diarrhea about four times a year.
Strep throat, caused by the bacteria group A streptococcus, manifests with symptoms of fever, swollen tonsils and stomach pain. KidsHealth reports strep throat spreads easily by coughing and sneezing, and is common among children and teens.
Sexually Transmitted Diseases
Sexually transmitted diseases, or STDs, are among the most common infectious diseases in the world. The University of Maryland Medical Center reports that there are more than 20 types of STDs affecting over 13 million men and women in the United States every year. The most common STDs include gonorrhea, chlamydia, syphilis and genital herpes.
Heart disease tops the list of killers of men and women worldwide, accounting for 40 percent of the deaths in the United States, according to the Mayo Clinic. Heart disease includes heart attack, valve disorders, rhythm irregularities and infections.
Type 2 Diabetes
Type 2 diabetes is the most common form of diabetes, affecting 23.6 million Americans, reports the American Diabetes Association. Diabetes is a condition where the blood glucose is too high.
Complications of uncontrolled diabetes include heart disease, stroke, elevated blood pressure, kidney disease, blindness and neuropathies, or nerve damage.