By Jesse Saffron, Relias Media Editor

Conjunctivitis — often called “pink eye” or “red eye” — is a common, relatively mild condition. But adenoviral conjunctivitis (AC) and its most severe presentation, epidemic keratoconjunctivitis (EKC), should be cause for concern for healthcare employees, experts say.

“This is a highly contagious infection. The worst form of it, EKC, almost crippled U.S. military operations in the Pacific Rim in World War II, and hence its nickname, ‘shipyard eye,’” says Irene C. Kuo, MD, associate professor of ophthalmology and chief of infection control at Johns Hopkins University School of Medicine’s Wilmer Eye Institute in White Marsh, MD.

That nickname references the 1941 outbreak in Navy shipyards at Pearl Harbor. Ten thousand people became infected with EKC, which quickly spread to the Western United States.1

AC can cause eye inflammation, eyelid swelling, extreme light sensitivity, excessive tearing, and ocular pain. EKC can produce those symptoms but also can cause dry-eye syndrome and affect the cornea, in severe cases distorting vision for months and even years.

Kuo says transmission occurs by contact with tears and ocular secretions. “Studies have shown that the desiccated virus is still viable on inanimate objects — metals, plastic, textiles, etc. — for up to 2-4 weeks,” she says.

EKC can be especially problematic in healthcare settings. High transmission rates can lead to worker furloughs, facility closures, and increased healthcare costs. And lack of proper infection control practices and employee training can exacerbate such problems.

In 2013, the CDC analyzed six EKC outbreaks that occurred in four states between 2008 and 2010, citing “significant morbidity and cost resulting from the number of persons affected, duration of the outbreaks, and the temporary closure of a neonatal intensive care unit and several clinics.”2

Numerous other facility outbreaks have been discussed in the literature, but the extent of the problem may be underestimated. “EKC is not a reportable condition, so there is no record kept of all cases,” says Marie Killerby, VetMB, MPH, an epidemiologist in the division of viral diseases at the CDC’s National Center for Immunization and Respiratory Diseases.

“I think now we have passive reporting; if a state calls us and they want assistance on an EKC outbreak, then we publish these reports,” she adds.

That EKC appears to be a low reporting priority at the national level may reflect that it often is perceived as low-risk; indeed, for many infected individuals, symptoms subside after 1-3 weeks. Still, the infection and AC in general present unique challenges for healthcare workers (HCWs). AC is a reportable condition in Germany and a Category IV infectious disease in Japan.

“It certainly deserves attention; it is difficult to deal with. It spreads very easily — it is a hardy virus that is resistant to some common disinfectants,” says Killerby.

A Close Call Spurs Reform

EKC is receiving significant attention at Johns Hopkins Medicine (JHM). In a recent paper3, Kuo and a colleague discuss a program created in 2011 “to ensure swift triage, accurate diagnosis, and appropriate work furlough for employees with adenoviral conjunctivitis.” The broader goal is “to prevent transmission of this infection and EKC in particular.”

Kuo, who initiated the program, says it has origins in an EKC scare that occurred years ago at JHM. “In the 1990s, my predecessor at Wilmer, Johns Hopkins’ department of ophthalmology, set up a policy that featured a ‘red-eye room’ in our eye emergency department as well as coded alerts because of a near-outbreak that almost shut down the department,” she says.

“When my current chairman closed the red-eye room and the eye emergency department, I talked with occupational health, hospital epidemiology and infection control, and virology and developed a new policy,” Kuo explains.

Key to the new approach was developing a polymerase chain reaction (PCR) assay to detect AC and EKC in swabs taken from hospital employees suspected of infection. It was created because PCR assays tailored for that purpose currently are not available on the market.

PCR tests are described in the paper as the “gold standard” in terms of accurate AC and EKC diagnosis. In contrast, “diagnosis by ophthalmologists may be 50% accurate at best, and diagnosis by other professionals is probably even less accurate.”

Of course, accurate diagnosis is not an end in itself. “The point is not to remove every employee who has red eye but only those with adenoviral conjunctivitis,” Kuo says. “If you over-call AC [or EKC] ... you put patient care at risk by having employees out of work.”

According to the paper, of 8,768 JHM employees who visited the occupational health clinic there from November 2011 through October 2016, “1,498 (17%) had eye complaints ranging from eye injury to red eye.” Of those, 1,059 were swabbed for suspicion of adenoviral infection. Twenty-six people had EKC, 78 had AC, and 673 had nonadenoviral conjunctivitis.

Median furlough length was 10 days for non-EKC infections and 14 days for EKC infections. These JHM areas had the largest AC and EKC infection numbers: outpatient pharmacy (9), surgery (8), ophthalmology (8), and medicine (8).

“Probably, the hospital employees are getting [infection] from the community,” Kuo says. “Luckily, and perhaps because of my policy, they are not spreading it at the hospital, but they certainly have potential to spread it to patients and other employees because it is so contagious.”

Kuo and her colleague note in the paper that the “proportion of red-eye employees having PCR-positive adenoviral conjunctivitis increased over five years … as did the proportion of employees with EKC.” However, they emphasize that the new policy has been beneficial in that it allows for better AC and EKC surveillance, which they say may help to prevent future outbreaks.

Other Important Strategies

It is likely that protecting HCWs and thwarting outbreaks will require more than adenoviral surveillance like that at JHM. The good news is that some recommendations are simple.

“Making sure everyone uses proper hand hygiene, making sure you are not having healthy patients going into a room right after an EKC patient, making sure you are using disinfectants that are effective — [those are important],” Killerby says.

“We [the CDC] recommend using EPA-registered disinfectants. The other thing is refraining from using eye drop bottles on multiple patients,” she adds. The CDC also recommends using disposable gloves and “making sure you’re disinfecting equipment after each use,” she says.

Such standard precautions are critical given that there are no proven treatments for adenoviral eye infections. A 2017 paper4 on EKC prevention says there is some evidence that topical corticosteroids can help alleviate symptoms, but in some cases, they have made symptoms last longer. The report says use of provodone-iodine eye drops may hold promise.

No matter what, says Kuo, caution should be used when it comes to antibiotics, which she says are wildly overprescribed in conjunctivitis cases and largely ineffective against AC and EKC. One problem is that physicians handling these cases often lack necessary training.

“It really is best that hospital employee health departments refer employees to ophthalmologists and not have employees run to urgent care, internists, or emergency rooms,” Kuo says.

“Ophthalmology is a small specialty, and MDs do not have much exposure, if any, to it unless they do residency. Many non-ophthalmologists prescribe antibiotics when unnecessary.”

Kuo says overprescribing in this area can cause negative side effects for patients and increase risk of antibiotic resistance. Further, costs in the hundreds of millions are imposed each year because of unnecessary prescriptions, trips to urgent care facilities and EDs, and missed work. “Probably more than a million patients are misdiagnosed and overtreated each year,” she says.

Nevertheless, Kuo seems acutely aware that her institution, JHM, is not alone in confronting issues related to AC and EKC. “Epidemics have occurred in other hospitals and medical and ophthalmology clinics, whereby both patients and employees developed infection,” she says.

“Regardless of whether it pops up in the community or hospital first, we need to have a high level of suspicion because infection is transmitted very easily.”


  1. Jawetz E. The story of shipyard eye. Br Med J 1959;1:873-876.
  2. CDC. Adenovirus-Associated Epidemic Keratoconjunctivitis Outbreaks — Four States, 2008-2010. MMWR 2013;62(32);637-641.
  3. Kuo IC, Espinosa C. Five-year trends in adenoviral conjunctivitis in employees of one medical center. Infect Control Hosp Epidemiol 2018;39:1080-1085.
  4. Hein AM, Gupta PK. Epidemic Keratoconjunctivitis: Prevention Strategies in the Clinic. EyeNet, February 2017:33-34.