Viral Infections

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Summary

Viruses are very tiny germs. They are made of genetic material inside of a protein coating. Viruses cause familiar infectious diseases such as the common cold, flu and warts. They also cause severe illnesses such as HIV/AIDS, Ebola, and COVID-19.

Viruses are like hijackers. They invade living, normal cells and use those cells to multiply and produce other viruses like themselves. This can kill, damage, or change the cells and make you sick. Different viruses attack certain cells in your body such as your liver, respiratory system, or blood.

When you get a virus, you may not always get sick from it. Your immune system may be able to fight it off.

For most viral infections, treatments can only help with symptoms while you wait for your immune system to fight off the virus. Antibiotics do not work for viral infections. There are antiviral medicines to treat some viral infections. Vaccines can help prevent you from getting many viral diseases.

Start Here

Bacterial vs. Viral Infections: How Do They Differ? (Mayo Foundation for Medical Education and Research) Also in Spanish

Diagnosis and Tests

Immunoglobulins Blood Test (National Library of Medicine) Also in Spanish
PCR Tests (National Library of Medicine) Also in Spanish
Rapid Tests (National Library of Medicine) Also in Spanish
Respiratory Pathogens Panel (National Library of Medicine) Also in Spanish

Prevention and Risk Factors

Germs and Hygiene: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
Infection Control: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

Related Issues

How Infections Spread (Centers for Disease Control and Prevention)

Specifics

Acute Flaccid Myelitis (National Library of Medicine) Also in Spanish
Adenoviruses (Centers for Disease Control and Prevention)
Croup: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
Enterovirus D68 (Centers for Disease Control and Prevention) Also in Spanish
Hand, Foot, and Mouth Disease (HFMD) (Centers for Disease Control and Prevention) Also in Spanish
HTLV-1-Associated Myelopathy (HAM)/Tropical Spastic Paraparesis (TSP) (National Institute of Neurological Disorders and Stroke)
Human Metapneumovirus (Cleveland Clinic Foundation)
Human Parainfluenza Viruses (HPIVs) (Centers for Disease Control and Prevention)
Molluscum Contagiosum (Centers for Disease Control and Prevention)
Non-Polio Enterovirus (Centers for Disease Control and Prevention)

Images

Molluscum Contagiosum (VisualDX)
Viral Exanthem (VisualDX)

Clinical Trials

ClinicalTrials.gov: Adenoviridae Infections (National Institutes of Health)
ClinicalTrials.gov: Coxsackievirus Infections (National Institutes of Health)
ClinicalTrials.gov: Enterovirus (National Institutes of Health)
ClinicalTrials.gov: Hand, Foot and Mouth Disease (National Institutes of Health)
ClinicalTrials.gov: Virus Diseases (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

Find an Expert

Children

Adenovirus (For Parents) (Nemours Foundation) Also in Spanish
Coxsackievirus Infections (For Parents) (Nemours Foundation) Also in Spanish
Enterovirus Infections (For Parents) (Nemours Foundation)
Hand-Foot-and-Mouth Disease (VisualDX)
Human Parainfluenza Viruses (Centers for Disease Control and Prevention)
Parechovirus (For Parents) (Nemours Foundation) Also in Spanish
Roseola (Sixth Disease) (VisualDX)
Viral Exanthem (VisualDX)

Patient Handouts

ECHO virus (Medical Encyclopedia) Also in Spanish
Enterovirus D68 (Medical Encyclopedia) Also in Spanish
Hand-foot-mouth disease (Medical Encyclopedia) Also in Spanish
Herpangina (Medical Encyclopedia) Also in Spanish
Molluscum contagiosum (Medical Encyclopedia) Also in Spanish
Parainfluenza (Medical Encyclopedia) Also in Spanish
Roseola (Medical Encyclopedia) Also in Spanish

Viral Infections

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