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- Smallpox facts
- What is smallpox?
- What is the history of smallpox?
- What causes smallpox?
- What are the risk factors for smallpox?
- Is smallpox contagious, and how long is it contagious?
- What is the incubation period for smallpox?
- How is smallpox transmitted?
- What are smallpox symptoms and signs?
- How do health-care professionals diagnose smallpox?
- What specialists treat smallpox?
- What is the treatment for smallpox?
- Can smallpox be prevented with a vaccine?
- What is the prognosis for smallpox, and what are complications of smallpox?
- Where can people find more information on smallpox?
Is smallpox contagious, and how long is it contagious?
Smallpox is highly contagious and remains contagious until all the scabs have fallen off. Usually, the contagious period takes about three to four weeks after the initial rash develops for the patient to be noncontagious.
What is the incubation period for smallpox?
The incubation period for smallpox is a little longer than that for many other viruses; symptoms develop about seven to 17 days after exposure.
How is smallpox transmitted?
Most transmission of smallpox is directly from person to person. Large, infectious droplets of saliva are expelled during coughing or sneezing and then inadvertently inhaled by another person. This usually requires close face-to-face contact and is similar to the way that mumps, measles, and influenza are spread. On average, a single individual would infect approximately 60% of their household contacts. Infected objects, such as used silverware or heavily contaminated bedding, may carry sufficient numbers of organisms to infect another person if improperly handled, although this route of transmission is much less common.