Most cases of conjunctivitis are caused by viruses, of which the most common microorganism is adenovirus [1] [2]. Viral conjunctivitis is often misdiagnosed as having a bacterial etiology, as viral conjunctivitis presents similarly to other types of conjunctivitis [3].

Pharyngoconjunctival fever (PCF) is a specific syndrome commonly caused by certain serotypes of the human adenovirus [4]. PCF can either occur sporadically or as an outbreak, however, it is more common in warm weather. Populations most susceptible to outbreaks are children in institutions such as schools, and people sharing living quarters. Most outbreaks originate from contaminated water bodies such as public swimming pools [5].

PCF and epidemic keratoconjunctivitis (EKC) are the more frequent syndromic manifestations of adenoviral infection of the eye. PCF is typically less severe than EKC [6]. The incubation period ranges from 5 days to almost 2 weeks, after which patients experience fever that usually resolves over the period of 10 days. There may be a history of exposure to individuals with conjunctivitis or pharyngitis, as infected individuals are highly contagious in the first few days of symptomatic infection. The infection is acute, self-limiting, and is more severe in patients with low immunity. Superimposed bacterial infection is possible.

PCF initially affects one eye, becoming bilateral as the infection progresses. Ocular manifestations include pronounced conjunctivitis. Common complaints are redness, burning, tearing, itching, and photophobia. In addition, there may be a watery discharge, edema, bruising, and tenderness of the eyelids.The appearance of the eye may resemble that of traumatic injury. The virus may occasionally cause the formation of a pseudomembrane (an even rarer occurrence in other types of conjunctivitis) which may be accompanied by a mucopurulent discharge, mostly consisting of mononuclear white blood cells. Subepithelial infiltrates (SEIs), white lesions on the cornea, are a consequence of the disease and may remain for months after the infection has cleared. This leads to possible visual disturbances, including decreased visual acuity.

The respiratory features of PCF are mainly pharyngitis and rhinitis, which vary in severity. Oropharyngeal erythema may be visualized.

Systemic symptoms include high-grade fever and tender or non-tender lymphadenopathy (approximately half of known cases), particularly in the cervical and preauricular regions [3]. Other non-specific features include general malaise and muscle pain.

The diagnosis of pharyngoconjunctival fever is clinical [7]. Possible studies carried out entail viral culture, adenovirus-specific antibody titers, polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and immunochromatography. Viral cultures may only be beneficial within the first 10 days of infection. Antibodies against the virus are gauged via complement fixation, where blood samples are drawn soon after symptoms appear, and then after 2 to 3 weeks later. An increase in antibodies in the second sample of at least four times the original sample is indicative of recent adenoviral infection. Typically, laboratory tests take about a week to yield results. Electron microscopy may also be utilized.

There is no specific antiviral treatment for pharyngoconjunctival fever. Management is mainly supportive and focuses on relieving symptoms. This can include the use of antipyretics for fever, analgesics for pain, and artificial tears for eye discomfort. In cases of severe conjunctivitis, topical antibiotics may be prescribed to prevent secondary bacterial infections.

The prognosis for pharyngoconjunctival fever is generally good. Most patients recover fully within one to two weeks without any long-term complications. However, the disease can be more severe in individuals with weakened immune systems, and they may require closer monitoring and supportive care.

Pharyngoconjunctival fever is caused by adenoviruses, particularly types 3, 4, and 7. These viruses are highly contagious and can spread through respiratory droplets, direct contact with infected individuals, or contact with contaminated surfaces. The virus can survive on surfaces for extended periods, facilitating its transmission.

PCF is more common in children and young adults, especially those in close-contact environments like schools, camps, and daycare centers. Outbreaks are more frequent in the late winter, spring, and early summer months. The disease can occur worldwide, but the incidence may vary based on local viral circulation patterns.

Adenoviruses infect the epithelial cells of the respiratory tract and conjunctiva, leading to inflammation and the characteristic symptoms of PCF. The virus can also affect the lymphoid tissue, contributing to the systemic symptoms such as fever and malaise. The immune response to the virus is responsible for the resolution of the infection.

Preventing the spread of pharyngoconjunctival fever involves good hygiene practices. Regular handwashing, avoiding close contact with infected individuals, and disinfecting surfaces can help reduce transmission. In outbreak settings, isolating affected individuals and ensuring proper sanitation can be effective in controlling the spread.

Pharyngoconjunctival fever is a contagious viral infection caused by adenoviruses, presenting with symptoms of sore throat, conjunctivitis, and fever. While the disease is self-limiting and generally resolves without complications, it can spread rapidly in group settings. Diagnosis is clinical, supported by laboratory tests if needed, and treatment is symptomatic.

If you or your child experience symptoms such as a sore throat, red eyes, and fever, it may be pharyngoconjunctival fever. This condition is caused by a virus and usually resolves on its own within a couple of weeks. To feel better, you can use over-the-counter medications for fever and pain, and eye drops for comfort. Remember to practice good hygiene to prevent spreading the virus to others.

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