Viruses

Viruses are the smallest known disease-causing microorganisms. Viral infections can be spread in many different ways. Following the rules of food safety will help prevent infection by some viruses but not by others. The list below shows how to minimize your risk of being infected by some common viruses.

Name	Symptoms	Prevention
Chicken pox	Characterized by an itchy rash, forming blisters that dry and become scabs. Fever and listlessness are also common.	Avoid affected individuals. It is highly contagious. A vaccine is available.
Epstein-Barr	Fatigue, fever, sore throat, and swelling of the lymph nodes and spleen.	Avoid oral contact (kissing) with affected persons. A vaccine is available.
Hepatitis A	Jaundice (yellowing of the skin), weakness, brownish urine, lack of appetite, and low-grade fever.	Avoid fecal-contaminated water due to poor sanitation and/or poor hygiene and poorly cooked food. No vaccine is available but a shot of gamma globulin increases resistance.
Hepatitis B	May have the virus without having any symptoms. Common symptoms include fatigue, loss of appetite, weakness, fever, nausea and vomiting. Can cause liver failure and death.	Avoid contact with the blood of or any sexual contact with infected persons. A vaccine is available.
Herpes	There are two strains of this virus: one causes cold sores around the mouth and the other causes blisters in the genital region; usually accompanied by flu-like symptoms.	Avoid direct contact with a cold sores or contact with infected fluid from the genitalia.
HIV	Causes AIDS (Acquired Immune Deficiency Syndrome), a condition where the bodies immune system is impaired. Can cause death.	Avoid sexual contact with or contact with the blood of an infected person.
Influenza	There are many strains of influenza but common symptoms include fatigue, loss of appetite, weakness, fever, nausea and vomiting. Influenza is sometimes fatal.	Highly contagious. Spreads through the air or by direct contact. Vaccines are available.
Measles	Causes a rash and high fever. In severe cases it leads to death through pneumonia, diarrhea or malnutrition.	Avoid the coughing or sneezing of an infected person. A vaccine is available.
Norwalk	Symptoms include nausea, vomiting, diarrhea and abdominal pain. May also cause low grade fever and headache.	Avoid contaminated water, foods and/or persons already infected. Avoid eating raw or partially cooked clams and oysters.
Polio	It can cause paralysis.	Take the polio vaccine.
Rabies	Attacks the nervous system causing general malaise, restlessness and inability to swallow. It is almost always fatal once symptoms have begun.	Avoid bites of an infected animal. It is suspected that transmission through the air is possible. A vaccine is available.
Rubella	Rash, slight fever, enlarged lymph nodes and headache. It can cause birth defects such as heart problems and deafness if contracted by a pregnant woman during the first 3 months of pregnancy.	Avoid afflicted individuals. A vaccine is available.
Yellow Fever	Symptoms include yellow skin and black vomit. It is often fatal.	Get vaccinated if traveling abroad. Spread by mosquitoes living close to populated areas.