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Summary
Smallpox is a disease caused by the Variola major virus. Some experts say that over the centuries it has killed more people than all other infectious diseases combined. Worldwide vaccination stopped the spread of smallpox three decades ago. The last case was reported in 1977. Two research labs still keep small amounts of the virus. Experts fear bioterrorists could use the virus to spread disease.
Smallpox spreads very easily from person to person. Symptoms are flu-like. They include:
- High fever
- Fatigue
- Headache
- Backache
- A rash with flat red sores
There is no treatment. Fluids and medicines for pain or fever can help control symptoms. Most people recover, but some can die. Those who do recover may have severe scars.
The U.S. stopped routine smallpox vaccinations in 1972. Military and other high-risk groups continue to get the vaccine. The U.S. has increased its supply of the vaccine in recent years. The vaccine makes some people sick, so doctors save it for those at highest risk of disease.
- Questions and Answers on Smallpox (World Health Organization)
- Smallpox (Mayo Foundation for Medical Education and Research) Also in Spanish
-
Smallpox
(National Institute of Allergy and Infectious Diseases)
- What Is Smallpox? (Centers for Disease Control and Prevention)
Symptoms
- Smallpox Signs and Symptoms (Centers for Disease Control and Prevention)
Prevention and Risk Factors
- Smallpox Vaccine (Centers for Disease Control and Prevention)
- Smallpox/Monkeypox Vaccine (JYNNEOS): What You Need to Know (Centers for Disease Control and Prevention) - PDF Also in Spanish
Clinical Trials
-
ClinicalTrials.gov: Smallpox
(National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Correlation between microneutralization test and a multiplexed immunoassay for evaluation of...
- Article: Safety and Efficacy of Repurposed Smallpox Vaccines Against Mpox: A Critical Review...
- Article: Use of JYNNEOS (Smallpox and Mpox Vaccine, Live, Nonreplicating) for Persons...
- Smallpox -- see more articles
Patient Handouts
- Smallpox (Medical Encyclopedia) Also in Spanish
- Smallpox/Monkeypox Vaccine (JYNNEOS): What You Need to Know (Centers for Disease Control and Prevention) - PDF Also in Spanish
The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.