variola

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.

Mpox, which used to be called monkeypox, is a disease caused by the monkeypox virus. This virus is in the same family of viruses as the smallpox virus.

Mpox can be spread between animals and people. It is found regularly in parts of Central and West Africa. The virus that causes it has been found in small rodents, monkeys, and other mammals that live in these areas.

Some outbreaks of mpox have affected people in many countries around the world, including the United States.

There are two types of monkeypox viruses:

• Clade I is regularly found in Central Africa. It causes more severe illness and deaths than clade II.
• Clade II is regularly found in West Africa. Infections from clade II are less severe. Most people who get this type will survive. This type is the cause of the global mpox outbreak that started in 2022.

Mpox spreads in different ways:

• Through close, personal contact with someone who has the virus:
  • Through direct contact with their rash, scabs, or body fluids
  • By breathing in the virus during prolonged, face-to-face contact
  • During intimate physical contact such as kissing, cuddling, hugging, massage or sex
• During pregnancy, from the pregnant person to the baby.
• From touching items (such as clothes, bedding, or towels) that were used by someone who has the virus
• From infected animals:
  • By being scratched or bitten by the animal
  • By preparing or eating meat or using products from the animal

Someone who has mpox can spread it from the time their symptoms start until their rash has fully healed, all scabs have fallen off, and a fresh layer of skin has formed. This usually takes 2-4 weeks.

Researchers have found that some people can spread mpox to others from 1 to 4 days before their symptoms appear. It is not known how often this happens.

The symptoms of mpox usually start within 3 weeks from the time you were exposed to the virus. The symptoms may include:

• A rash with sores that can look like pimples or blisters. It could be on the face, inside the mouth, and on other parts of the body, like the hands, feet, chest, genitals, or anus. It goes through different stages, including scabs, before healing. This can take 2-4 weeks.
• Fever.
• Chills.
• Swollen lymph nodes ("swollen glands").
• Exhaustion.
• Headache.
• Muscle aches and backache.
• Respiratory symptoms, such as a sore throat, nasal congestion, or cough.

You may have all or only a few symptoms:

• You may get a rash first, followed by other symptoms
• You may have flu-like symptoms and then develop a rash 1-4 days later
• You may only get a rash

To find out if you have mpox, your health care provider:

• Will ask about your symptoms and medical history.
• Will look at your rash.
• Will take a sample of tissue from one of the sores so it can be tested for the monkeypox virus.
• May do blood tests to check for monkeypox virus or for antibodies to the virus. Antibodies are proteins that your immune system makes to fight foreign substances such as viruses and bacteria.

There are no treatments specifically for mpox, but many people get better on their own.

Since mpox and smallpox are similar, antiviral medicines that treat smallpox may also help treat mpox. Antiviral medicines may be recommended for people have severe mpox or are at risk of severe mpox, for example because they:

• Have immune system, for example from HIV or other conditions
• Are pregnant
• Are children, especially those under age 1
• Have certain active skin conditions that can cause widespread infection, such as eczema, impetigo, or psoriasis

If you have mpox, it is recommended that you stay home from the time you have symptoms until your mpox rash has healed and a new layer of skin has formed. It would be best to stay in a separate room from your family members and pets if you can.

JYNNEOS is a vaccine that can help prevent mpox (and smallpox). The vaccine is given in two doses 4 weeks apart. Getting both doses gives the best protection.

The vaccine is recommended for people who are at risk of mpox, for example because they:

• Had or think they could've had exposure to someone with mpox
• Are a man who has sex with men, a transgender person, or a gender non-binary person who in the last 6 months had:
  • One or more sexually transmitted infections
  • More than one sexual partner
  • Sex at a commercial sex venue (like a sex club or bathhouse)
  • Sex at a large public event where people had spread mpox
• Had a sex partner who is at risk of mpox
• Expect to be in any of these situations
• Are at risk of exposure at work, for example at a lab or healthcare facility

Check with your provider to see if the vaccine is recommended for you.

There are also other steps you can take to help prevent mpox:

• Avoid close, skin-to-skin contact with the mpox rash. So, while a person is sick with mpox:
  • Do not touch their rash or scabs
  • Do not kiss, hug, cuddle, or have sex with them
• Avoid contact with items that were used by someone who has mpox:
  • Do not touch the bedding, towels, or clothing of a person who has mpox
  • Do not share eating utensils or cups with them
  • If you or someone you live with has mpox, clean and disinfect your home
• Wash your hands often with soap and water or use an alcohol-based hand sanitizer, especially after contact with sick people.

Centers for Disease Control and Prevention

A bioterrorism attack is the deliberate release of viruses, bacteria, or other germs to cause illness or death. These germs are often found in nature. But they can sometimes be made more harmful by increasing their ability to cause disease, spread, or resist medical treatment.

Biological agents spread through the air, water, or in food. Some can also spread from person to person. They can be very hard to detect. They don't cause illness for several hours or days. Scientists worry that anthrax, botulism, Ebola and other hemorrhagic fever viruses, plague, or smallpox could be used as biological agents.

Biodefense uses medical measures to protect people against bioterrorism. This includes medicines and vaccinations. It also includes medical research and preparations to defend against bioterrorist attacks.

Centers for Disease Control and Prevention