The World Health Organization (WHO) declared mpox a Public Health Emergency of International Concern (PHEIC) twice in recent years—first in 2022 and again in 2024—following significant international outbreaks. Historically considered endemic in parts of Central and West Africa, mpox has increasingly spread to new regions, highlighting the evolving nature of the disease and its public health implications.
Mpox Virus and Its Genetic Clades
Mpox is caused by the monkeypox virus (MPXV), a member of the Orthopoxvirus genus. Through phylogenetic analysis, scientists have classified the virus into two major lineages: clade I and clade II. These groups were previously known as the Congo Basin clade and the West African clade, respectively. Each lineage is further subdivided into Ia, Ib, IIa, and IIb.
The 2022 global mpox outbreak was largely driven by clade IIb, which spread across several continents. By contrast, the 2024 outbreak was declared in response to rising infections caused primarily by clade Ib, a strain that has raised concerns due to its emergence beyond traditional endemic areas and its possible increased transmissibility.
Between January 2022 and November 2025, more than 170,000 cases and over 460 deaths were recorded worldwide. In response to the escalating spread of clade Ib infections across Africa, the Africa Centres for Disease Control and Prevention (Africa CDC) declared the outbreak a Public Health Emergency of Continental Security (PHECS) in August 2024.
Importance of Early Recognition in Clinical Practice
Because general healthcare providers often represent the first point of contact for patients with mpox symptoms, awareness of the disease’s potential complications is critical. In particular, increasing evidence suggests that mpox can affect the eyes, sometimes leading to severe and irreversible visual damage.
Recognizing ophthalmic involvement early can allow for timely referral to specialists and rapid initiation of antiviral therapy, reducing the likelihood of serious complications.
Epidemiology of Mpox-Related Ophthalmic Disease
Reports of mpox-related ophthalmic disease (MPXROD) vary widely across studies. Differences appear to be influenced by geographic location, viral clade, and the severity of outbreaks.
During the 2022 clade IIb outbreak, ocular complications were documented in approximately 1% to 8% of mpox cases. Most patients experienced favorable visual outcomes, but some cases resulted in significant vision loss, particularly when corneal disease such as keratitis developed.
Research conducted before the 2022 global outbreak indicates that eye involvement may be more common than previously recognized. A systematic review of earlier mpox cases reported conjunctivitis in more than 20% of patients, while a Nigerian study found that about 25% of patients presented with ophthalmic symptoms at the onset of illness.
Recent outbreaks have also documented eye pain and visual disturbances in both adults and children, underscoring the need for clinicians to remain vigilant.
Populations at Higher Risk
Certain groups appear to face a greater risk of severe ocular disease. Individuals with compromised immune systems, particularly those living with HIV infection, are more susceptible to serious complications. Patients experiencing severe systemic mpox infection also appear more likely to develop eye involvement.
Systemic Features of Mpox
Mpox typically begins with a prodromal phase, which includes symptoms such as:
- Fever
- Headache
- Fatigue
- Muscle aches (myalgia)
- Prominent lymphadenopathy (swollen lymph nodes)
This stage is followed by the eruptive phase, characterized by the development of skin lesions. These lesions progress through several stages—from macules to papules, vesicles, and ultimately pustules.
Clinicians should suspect mpox in patients who exhibit these symptoms and have risk factors such as:
- Travel to endemic areas
- Close contact with a confirmed case
- Exposure through sexual networks
Ocular Symptoms and Clinical Signs
Ocular symptoms can appear either during the initial phase of the illness or several weeks after the onset of the skin rash. Studies suggest that eye complications typically develop about 21 days after cutaneous lesions appear, although the timeline can vary.
Common ocular symptoms include:
- Eye pain
- Redness and tearing
- Photophobia (light sensitivity)
- Blurred or decreased vision
- Eye discharge
- Periorbital swelling
In some cases, ocular symptoms occur without facial lesions, making diagnosis more challenging. Healthcare providers must therefore consider mpox in patients presenting with eye symptoms who also have epidemiological risk factors.
How the Virus Reaches the Eye
One possible mechanism for ocular infection is autoinoculation, where patients transfer the virus from skin lesions to the eye by touching infected areas and then rubbing or touching the eyes.
Researchers have also suggested that the conjunctiva itself may serve as a route of viral entry, particularly in high-risk exposures such as close physical or sexual contact.
Areas of the Eye Affected
Mpox can affect several structures of the eye and surrounding tissues, including:
- The periorbital region
- The ocular adnexa
- The anterior segment of the eye
Specific anatomical areas that may be involved include the eyelids, conjunctiva, cornea, and sclera.
Typical symptoms associated with these forms of involvement include:
- Ocular pain
- Redness
- Tearing
- Photophobia
- Discharge
- Periorbital swelling
- Decreased vision
Eyelid and Periocular Disease
Among the most common manifestations of ocular mpox are eyelid and periocular lesions. Documented findings include:
- Preseptal cellulitis
- Eyelid edema
- Pustular or nodular lesions
- Blepharitis
- Rare cases of necrosis affecting the eyelid skin
These symptoms were observed in outbreaks both before and after the 2022 global spread.
Anterior Segment Complications
The virus can also affect the anterior segment of the eye, leading to conditions such as:
- Conjunctivitis
- Conjunctival or subconjunctival lesions
- Keratitis
- Keratoconjunctivitis
- Corneal edema
- Corneal epithelial defects or ulcers
- Keratic precipitates
- Corneal scarring or opacities
- Scleral edema
Although many mild cases resolve without long-term damage, corneal involvement significantly increases the risk of permanent vision loss.
A report published in The Lancet Infectious Diseases described two immunocompromised patients who developed ulcerative keratitis that progressed to corneal perforation and damage to the globe.
Intraocular Disease
While less frequently reported, mpox can also affect structures within the eye itself. Uveitis, an inflammatory condition affecting the uveal tract, has been documented in both systemic mpox and cases where ocular infection occurred in isolation.
One particularly severe case involved a 53-year-old patient who developed fulminant scleritis, keratitis, and uveitis. Laboratory testing confirmed the presence of mpox RNA in the patient’s aqueous humor, highlighting the virus’s ability to invade intraocular tissues.
Potential Complications
If not promptly treated, ocular mpox can lead to serious complications, including:
- Bacterial superinfection
- Eyelid deformities
- Corneal perforation
- Corneal staphyloma
In severe cases, these complications can result in permanent visual impairment or irreversible blindness.
Diagnostic Approach
Diagnosis of ocular mpox is often initially based on clinical findings. Confirmation of systemic infection is typically achieved through PCR testing of skin or mucosal lesions.
When eye involvement is suspected, PCR testing of conjunctival swabs may help confirm the presence of MPXV on the ocular surface.
However, clinicians must also consider other possible causes of similar symptoms, including infections caused by:
- Herpes simplex virus
- Varicella-zoster virus
- Adenovirus
- Bacterial conjunctivitis
Importance of Patient History
Obtaining a detailed patient history is crucial for identifying potential exposure risks and establishing the timeline of symptoms. Key questions should address:
- Contact lens use
- Touching or manipulating skin lesions
- Immune status, particularly HIV status and CD4 count
- Sexual network exposure
- Recent travel history
- Known contact with confirmed mpox cases
Ophthalmic Examination
An appropriate eye examination should include baseline visual acuity testing followed by careful inspection of the eyelids and periorbital tissues for lesions.
Clinicians should also assess the ocular surface for conjunctival injection or signs of keratitis. For patients reporting eye pain, photophobia, or foreign-body sensation, fluorescein staining is recommended to detect corneal epithelial defects or ulceration.
Patients with confirmed mpox infection or those with high-risk exposure histories should be closely monitored, with prompt referral to an ophthalmologist if ocular symptoms develop.
When Urgent Referral Is Needed
Immediate ophthalmologic evaluation is recommended for patients presenting with:
- Decreased visual acuity
- Corneal epithelial defects
- Corneal opacity visible on fluorescein staining
- Severe photophobia
- Hypopyon or marked inflammation of the anterior chamber
- Signs suggestive of orbital cellulitis
Management Strategies
Management of mpox is generally similar regardless of the viral clade. Supportive care—such as pain control, hydration, wound care, and treatment of secondary bacterial infections—remains the cornerstone of treatment for systemic disease.
However, ocular involvement warrants antiviral therapy because of the high risk of vision-threatening complications.
The Centers for Disease Control and Prevention (CDC) recommends considering systemic antiviral therapy for all severe mpox cases, including those with eye manifestations.
Antiviral Treatment
The preferred antiviral medication is Tecovirimat, which is recommended for patients with severe disease or risk factors for progression.
Indications for its use include:
- Immunocompromised status
- Children younger than eight years
- Pregnancy
- Extensive skin disease
- Ocular mpox
Early initiation of antiviral therapy appears to reduce disease progression and improve outcomes.
When tecovirimat is unavailable or contraindicated, alternative or adjunctive therapies may include:
- Brincidofovir
- Cidofovir
- Vaccinia immune globulin
Topical and Supportive Eye Treatments
Topical therapy may provide additional benefit in patients with ocular involvement. The antiviral eye drop Trifluridine 1% solution has demonstrated activity against Orthopoxviruses and has been used off-label in case reports.
Supportive treatments may include:
- Lubricating eye drops to relieve irritation
- Topical antibiotics to prevent or treat bacterial superinfection
- Cool compresses to reduce pain and swelling
Topical corticosteroids are generally avoided because they may enhance viral replication unless specifically recommended by an ophthalmologist.
Surgical intervention is reserved for severe or refractory cases.
Practical Guidance for Frontline Clinicians
Healthcare providers should incorporate routine screening for ocular symptoms when evaluating patients with suspected mpox. Early detection can significantly improve outcomes.
Recommended clinical steps include:
- Examining the eyes in all suspected mpox cases
- Actively asking patients about visual symptoms
- Educating patients on avoiding autoinoculation by touching lesions and then touching the eyes
- Initiating systemic antiviral therapy when ocular involvement is suspected
- Referring patients urgently to ophthalmology if visual symptoms or corneal disease are present
Importance of Multidisciplinary Care
Optimal management of ocular mpox often requires collaboration among general practitioners, ophthalmologists, and infectious disease specialists. Even when no eye symptoms are present initially, patients should be educated on strict hand hygiene and infection-control measures to reduce the risk of self-inoculation.
As mpox continues to spread and evolve, heightened clinical awareness of its ophthalmic manifestations will be essential to preventing avoidable vision loss and ensuring comprehensive patient care.