Smallpox is an infectious ancient disease caused by the Variola virus. Before smallpox was eradicated, it was a serious infectious and contagious; disease; it spread from one person to another.

Epidemiological Triad

Agent  –  The causative agent of smallpox is the Variola virus (DNAvirus).

Host  – All age group, Both sexes

Environment –  Overcrowded place

Mode of Transmission

Smallpox is an airborne disease. So this is the one of reasons smallpox was so dangerous and deadly. Airborne diseases more tend to be spread fast.

1. Droplet nuclei (aerosols formed)

2. Droplet infection (airborne droplets) 

3. Directly from person to person – By coughing, sneezing, or direct contact with any bodily fluids of an infected person.

4. Via contaminated items – Sharing contaminated material or object increase risk of infection such as clothing, bedding or fomites.  

Incubation Period

Infection with variola virus begins with an incubation period usually between 7 to 17 days (range 10 to 14 days).

Clinical Manifestation

Sign and symptoms of smallpox include-

1. High fever as 101°F to 105°F

2. Chills

3. Headache

4. Severe backache

5. Abdominal pain

6.  Vomiting

7. Convulsion

8. Appearance of rashes in centrifugal distribution

9. Severe fatigue

Early symptoms include high fever headache, and a backache.

Then the virus produces a characteristic rash, the rash started on the face and then spread to the hands, forearms, and the main part of the body.

How smallpox spread?

Variola virus spread through coughed or sneezed and droplets from nose or mouth of infected person to to other people.

The variola virus can also spread through contaminated materials or object such as bedding or clothing of infected person.

When sores in the mouth start breaking a rash developed on the skin, appears on the face and start spreading to the arms and legs, and then also to the hands and feet.

A small red spots (early rash stage) starts as on the tongue and in the mouth. These spots are developed into sores and that breaking open, large amounts of the virus spread into the mouth and throat. The person continues experience to have a fever.

The rash developed into spots become filled with clear fluid and then  turn into abscesses filled with fluid and pus. Later these abscesses break open, form a crust and scab dries up and falls off and leaving mark scars.  

Scabs and the fluid found in the sores of smallpox patient’s also contained the variola virus.

Types of Smallpox

There were two common forms of smallpox were known as variola minor, which causes mild smallpox, and variola major, which severe form of smallpox, with a more extensive rash and higher fever. It is  most common form of smallpox.

Treatment for Smallpox

For smallpox, there is no cure. As a result of worldwide, repeated vaccination programs had executed. Officially declared that variola virus (smallpox) has been completely eradicated.

Complications of Smallpox

Most people who infected with smallpox get survive. These infection cause severe forms in pregnant women and people with weakened immune systems.

Those people recovered from smallpox mostly have severe lifelong scars, especially on their face, arms and legs and in some person smallpox cause blindness.

Prevention of Smallpox

1. Isolate the infected person to control the spread of the virus

2. Smallpox vaccination

Smallpox infection can be preventable by smallpox vaccine, called vaccinia virus vaccine. The smallpox vaccine is made from a vaccinia which is a poxvirus.

Currently, the vaccine for smallpox is not available for general public because smallpox had eradicated, and virus no longer exists in nature.

Smallpox FAQ

1. What is smallpox?

Smallpox is an infectious ancient disease. Causative agent of smallpox is Variola virus.

2. How does smallpox spread?

Variola virus transmitted through coughed or sneezed and droplets from infected person to other or spread through sharing contaminated materials or objects such as bedding or clothing of  infected person.

3. Is a smallpox vaccine currently available?

Vaccine against smallpox infection was a key tool for was eradication of smallpox. it protected humans against smallpox disease. Since small pox disease eradicated, vaccine is not recommended in routine immunization for general public. 

Vaccine can be used to protect anyone who has a high risk of exposure to smallpox.

4. Can smallpox be treated?

There is no cure for smallpox infection, but vaccination can be used very effectively to prevent infection from developing infection.

since smallpox was eradicated,  New antiviral drugs available,  for treatment of smallpox infection.

5. What is the difference between smallpox and chickenpox?

The causative agent of Smallpox is Variola virus (Pox Virus) and the causative agent of Chickenpox is Varicella Zoster Virus (Herpes Virus).