Monkeypox is a rare disease caused by infection with the monkeypox virus. Monkeypox virus is part of the same family of viruses as variola virus, the virus that causes smallpox. Monkeypox symptoms are similar to smallpox symptoms, but milder, and monkeypox is rarely fatal. Monkeypox is not related to chickenpox.
Monkeypox was discovered in 1958 when two outbreaks of a pox-like disease occurred in colonies of monkeys kept for research. Despite being named "monkeypox," the source of the disease remains unknown. However, African rodents and non-human primates (like monkeys) might harbor the virus and infect people.
The first human case of monkeypox was recorded in 1970. Prior to the current 2022 outbreak, monkeypox had been reported in people in several central and western African countries. Previously, almost all monkeypox cases in people outside of Africa were linked to international travel to countries where the disease commonly occurs or through imported animals. These cases occurred on multiple continents.
How It Spreads
Monkeypox spreads in a few ways:
- Monkeypox can spread to anyone through close, personal, often skin-to-skin contact, including:
- Direct contact with monkeypox rash, scabs, or body fluids from a person with monkeypox.
- Touching objects, fabrics (clothing, bedding, or towels), and surfaces that have been used by someone with monkeypox.
- Contact with respiratory secretions.
- This direct contact can happen during intimate contact, including:
- Oral, anal, and vaginal sex or touching the genitals (penis, testicles, labia, and vagina) or anus of a person with monkeypox.
- Hugging, massage, and kissing.
- Prolonged face-to-face contact.
- Touching fabrics and objects during sex that were used by a person with monkeypox and that have not been disinfected, such as bedding, towels, and sex toys.
- A pregnant person can spread the virus to their fetus through the placenta.
It's also possible for people to get monkeypox from infected animals, either by being scratched or bitten by the animal or by preparing or eating meat or using products from an infected animal.
A person with monkeypox can spread it to others from the time symptoms start until the rash has fully healed and a fresh layer of skin has formed. The illness typically lasts 2-4 weeks.
Scientists are still researching if the virus can be spread when someone has no symptoms and other aspects of transmission.
Signs and Symptoms
Symptoms of monkeypox can include:
- Muscle aches and backache
- Swollen lymph nodes
- Respiratory symptoms (e.g. sore throat, nasal congestion, or cough)
- A rash that may be located on or near the genitals (penis, testicles, labia, and vagina) or anus but could also be on other areas like the hands, feet, chest, face, or mouth.
- The rash will go through several stages, including scabs, before healing.
- The rash can look like pimples or blisters and may be painful or itchy.
You may experience all or only a few symptoms
- Sometimes, people get a rash first, followed by other symptoms. Others only experience a rash.
- Most people with monkeypox will get a rash.
- Some people have developed a rash before (or without) other symptoms.
Monkeypox symptoms usually start within 3 weeks of exposure to the virus. If someone has flu-like symptoms, they will usually develop a rash 1-4 days later.
Monkeypox can be spread from the time symptoms start until the rash has healed, all scabs have fallen off, and a fresh layer of skin has formed. The illness typically lasts 2-4 weeks.
Take the following steps to prevent getting monkeypox:
- Avoid close, skin-to-skin contact with people who have a rash that looks like monkeypox.
- Do not touch the rash or scabs of a person with monkeypox.
- Do not kiss, hug, cuddle or have sex with someone with monkeypox.
- Avoid contact with objects and materials that a person with monkeypox has used.
- Do not share eating utensils or cups with a person with monkeypox.
- Do not handle or touch the bedding, towels, or clothing of a person with monkeypox.
- Wash your hands often with soap and water or use an alcohol-based hand sanitizer, especially before eating or touching your face and after you use the bathroom.
How can a person lower their risk during sex?
Talk to your partner about any recent illness and be aware of new or unexplained rashes on your body or your partner's body, including the genitals and anus. If you or your partner have recently been sick, currently feel sick, or have a new or unexplained rash, do not have sex and see a healthcare provider.
If you or a partner has monkeypox, the best way to protect yourself and others is to avoid sex of any kind (oral, anal, vaginal) and do not kiss or touch each other's bodies while you are sick, especially any rash. Do not share things like towels, fetish gear, sex toys, and toothbrushes.
There are no treatments specifically for monkeypox virus infections. However, monkeypox and smallpox viruses are genetically similar, which means that antiviral drugs and vaccines developed to protect against smallpox may be used to prevent and treat monkeypox virus infections.
Antivirals, such as tecovirimat (TPOXX), may be recommended for people who are more likely to get severely ill, like patients with weakened immune systems.
If you have symptoms of monkeypox, you should talk to your healthcare provider, even if you don't think you had contact with someone who has monkeypox.
CDC recommends vaccination for people who have been exposed to monkeypox and people who may be more likely to get monkeypox.
People more likely to get monkeypox include:
- People who have been identified by public health officials as a contact of someone with monkeypox
- People who are aware that one of their sexual partners in the past 2 weeks has been diagnosed with monkeypox
- People who had multiple sexual partners in the past 2 weeks in an area with known monkeypox
- People whose jobs may expose them to orthopoxviruses, such as:
- Laboratory workers who perform testing for orthopoxviruses
- Laboratory workers who handle cultures or animals with orthopoxviruses
- Some designated healthcare or public health workers
(Information current as of 9/2/2022)
Persons no longer need to register for a vaccine clinic and persons can self-attest they meet eligibility for vaccine. For monkeypox vaccine clinics run by the Los Angeles County Department of Public Health, please see the information at:
For monkeypox vaccination by the Pasadena Public Health Department, persons may sign up to be on an on-call list and will be contacted when vaccination is available:
LACDPH Eligibility Criteria for MPX Vaccine (9/9/22)
Gay or bisexual men, or any men or transgender people who have sex with men or transgender people.
Persons of any gender or sexual orientation who engage in commercial and/or transactional sex (e.g., sex in exchange for money, shelter, food, or other goods or needs).
Persons living with HIV, especially persons with uncontrolled or advanced HIV disease.
Persons who had skin-to-skin or intimate contact with someone with suspected or confirmed monkeypox, including those who have not yet been confirmed by Public Health.
Gay or bisexual men or transgender people who:
- Had multiple or anonymous sex partners in the past 14 days
- Had skin-to-skin or intimate contact with persons at venues or events in the past 14 days
- Had a history of early syphilis or gonorrhea in the past 12 months
- Are on HIV pre-exposure prophylaxis (PrEP)
- Had anonymous sex or sex with multiple partners in the past 21 days in a commercial sex venue or other venues.
Persons can self-attest that they meet the criteria. Go to the LACDPH site to get information about sites providing vaccine.
What to do if you have possible symptoms of Monkeypox or have been exposed to Monkeypox
Please contact the Health Services of Caltech Student Wellness Services by telephone (626) 395-6393 (Monday-Friday, 8:00am-5:00pm) or through a secure message via the Health Portal at the Caltech Student Wellness Services Website (for non-urgent messages). If the Caltech Health Services is not available or your need is urgent, please go to a local urgent care facility. Please call ahead to the facility and let them know your circumstances so they can prepare for your visit and reduce the risk of spreading a possible infection. Please cover any rash areas with clothing, wear a mask, and avoid close or skin-to-skin contact with others.