Young woman with monkeypox rash holding her arms crossed

How Human Monkeypox Affects the Eyes

In May 2022, the World Health Organization declared (yet another) international public health emergency. While still reeling from COVID-19, planet Earth now also has to deal with a global monkeypox outbreak. Although much less sensationalized (and deadly) compared to the SARS-CoV-2 virus and COVID-19, the monkeypox virus is still causing some disruption with over 30,000 cases and 32 deaths in the US as of mid-February 2023. And at the time of writing, in the lead for the highest case count of monkeypox is the state of California.

What You Should Know About Monkeypox

Monkeypox is a virus from the same family as the smallpox. It’s so named because it was first found in a group of lab monkeys in 1958; in 1970 the first human outbreak of monkeypox was recorded in the Democratic Republic of the Congo.

Although the monkeypox virus didn’t just disappear after the first outbreak, it’s thought to have resurfaced now – and aggressively so – due to routine smallpox vaccinations being discontinued. Being closely related, it’s thought that the smallpox vaccination provided some cross-protection against the monkeypox virus as well as limited its transmission between humans.

Infection with the monkeypox virus is mostly self-limiting, meaning it runs its course and then resolves on its own over two to four weeks. It often presents with a fever, chills, muscle aches, headache, swollen lymph nodes, and severe fatigue. The disease’s hallmark is a rash all over the body, which follows a specific pattern and can be painful and/or itchy. Doctors have also realized that, like COVID-19, infection by the monkeypox virus can also lead to signs and symptoms around the eyes.


How Human Monkeypox Affects the Eyes

The eyes and surrounding tissues of the eyes can be affected by the virus in a few ways. The most common ocular findings among people infected with human monkeypox are:

  • Conjunctivitis
  • Swelling of the eyelids
  • The tell-tale monkeypox rash on the eyelids and surrounding skin
  • Inflammation of the eyelids (blepharitis)

These ocular signs, though distressing (and probably quite unsightly to behold), tend to just be temporary and, as mentioned, will resolve over time. However, the more concerning of the eye-related complications is keratitis, which refers to infection and inflammation of the cornea, the transparent dome of tissue at the very front surface of the eye. Scarring from infection to this tissue can lead to permanent loss of vision. On top of that, if bacteria take advantage of the cornea’s defenses being down from viral infection, it can result in other sight-threatening complications, such as perforation of the cornea.

Interestingly, ocular signs of human monkeypox infection have been found to be related to the severity of the disease overall. For example, people with conjunctivitis were more likely to experience nausea, chills, mouth ulcers, sore throat, and swollen lymph nodes. These patients were also more likely to have more severe symptoms and be bed-ridden compared to those without eye-related symptoms.

Those who have not been vaccinated against smallpox are more likely to experience ocular presentations of human monkeypox infection, which highlights the role of smallpox immunization in providing some protection against its brother virus, monkeypox. One study found 74% of people who encountered eye-related monkeypox symptoms were unvaccinated against smallpox compared to just under 40% in those vaccinated.


How Can I Protect My Eyes Against Monkeypox?

The best way of protecting your eyes is to protect, well, your entire body. Just don’t get infected, which is obviously easier said than done. Transmission of monkeypox between humans occurs via respiratory secretions (such as being sneezed on), touching infected skin lesions (you shouldn’t do that), or coming into contact with recently contaminated objects and surfaces (but how is one to know?). Unfortunately, there have also been cases of transmission from pregnant mother to fetus, leading to miscarriage or congenital monkeypox.

If hiding away from humanity in the forest is not an option (and in fact, living in forested areas is a risk factor for human monkeypox), then the most effective thing you can do to protect yourself is to ensure you’re vaccinated against smallpox. Data tells us that smallpox vaccination provides 85% protection against the human monkeypox virus. Other sensible measures suggested by the CDC include:

  • Avoid skin-to-skin contact with people sporting a monkeypox rash
  • Avoid contact with objects that an infected patient has touched
  • Wash your hands often
  • If you feel so inclined to travel to Central or West Africa, avoid contact with rodents and primates, which are the most common animals responsible for spreading the virus

More specific to protecting your vision in the face of monkeypox infection, researchers have suggested using lubricating eyedrops to prevent abrasions or other injury to the eye’s surface that bacteria may take advantage of. If you do develop monkeypox manifestations of the cornea, your eye doctor may consider off-label prescription of certain topical antiviral medications that tend to be effective against the family of viruses that monkeypox belongs to.

Nowadays it can feel like if it’s not one viral invasion, it’s another. At the moment, researchers are still working on understanding the nitty-gritty details of how the monkeypox virus affects the eyes and how more effective therapies can be developed. In the meantime, if you have a monkeypox infection and are concerned about your vision, contact your local eye doctor for advice.