Viral Diseases Diseases that are caused by viruses

Viral Diseases � Diseases that are caused by viruses that enter the body and multiply. � The Common Cold a group of symptoms that is caused by a number of different viruses. � Most colds last 3 -7 days. � Colds spread when a person touches a contaminated object or inhales droplets from a sneeze or a cough. � There is no cure for the common cold

Influenza � Common viral infection of the upper respiratory system. � High fever, sore throat, headache, and cough are typical symptoms. � Influenza viruses can cause more serious illness than the cold virus. � On average, over 30, 000 people die each year from the flu.

Influenza � Some types of the flu can be avoided with an immunization or “flu shot. ” � Flu virus is especially dangerous for young children, the elderly, and people with heart and lung disease. � Pg. 560 figure 9 describes the stages of the flu.

Pneumonia �A series infection of the lungs. � People who are elderly, have heart disease, or breathing problems, the flu may develop into pneumonia. � Can be caused by a virus, bacteria, or fungi. � Many people die each year from this illness.

Hepatitis � Inflammation of the liver. � This is a very series disease. � Symptoms may include fever, nausea, pain in the abdomen, and jaundice (yellowing of the skin. ) � The most common types are identified as type A, Type B, and Type C.

Hepatitis A � Is transmitted in human wastes and contaminated water and food. � Illness begins about 4 weeks after exposure, and recovery takes several weeks. � A vaccine for Hepatitis A can effectively prevent this disease.

Hepatitis B � More severe than type A. � Can be transmitted in blood or during sexual contact. � Can also be transmitted during tattooing or body piercing if tools are not properly sterilized. � Over 1 million Americans carry this illness, even though there is a vaccine.

Hepatitis C � Also more severe than type A. � Can be transmitted the same ways as Type B. � This illness is the number 1 reason for liver transplants in the U. S. � Approximately 3 million Americans carry hepatitis C.

Treating Viral infections � In most cases, there is no particular medicine that can cure a viral infection. � Antibiotics are only effective against bacterial infections-not viruses. � The best treatments for viral infections are rest, a well-balanced diet, and plenty of fluids. � Many over-the-counter medicines can treat the symptoms of a viral illness.

What is an emerging Disease? � Epidemic an unusually high occurrence of a disease in a certain place during a certain time period. � If an epidemic affects many areas of the world, it is referred to as a pandemic. � Epidemics of various diseases that occur today are known as emerging diseases.

Emerging disease � an infectious disease that has become increasingly common in humans within the last 20 years or threatens to become more common in the near future. � Diseases can emerge when humans come in contact with infected animals; pathogens become resistant to existing drugs; or people lack appropriate immunizations. � International travel and the global food supply help enable emerging diseases to spread quickly.