26 McConnell.kateesha

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An Outbreak of Acanthamoeba

Keratitis Among Contact Lens

Users – Florida, 2005-2007Statewide Epidemiology Seminar

May 2008

Kateesha McConnell, MPH

Florida Epidemic Intelligence Service Fellow

Roberta M. Hammond, PhD, RS – Bureauof Community Environmental Health, Food and

Waterborne Disease Program

Roger Sanderson, RN, MA

Regional Epidemiologist 2

Acanthamoeba keratitis (AK)

Rare and serious eye infection

Incidence of the disease in the US is estimated at 1-2cases per million contact lens (CL) users

Healthy individuals can get infection but AK primarily inCL users

Unhygienic CL practices, hx of trauma, environmentalfactors

Can cause severe vision outcomes

3

Acanthamoeba

Microscopic amoeba

Common to the Environment

Water

Soil

Air

Drinking water

Sewage systemsSource: Clinical Microbiology Reviews 2003;(16)2; 273-307.

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Acanthamoeba

Cause of several infections in humans

Acanthamoeba keratitis (AK)

Granulomatous Amebic Encephalitis (GAE)

Disseminated infection

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Risk Factors for AK

Improper storage and handling of lenses

Improper disinfection of lenses (ie. Use of tap water orhomemade solutions to clean the lenses)

Swimming, using a hot tub, or showering while wearinglenses

Coming into contact with contaminated water

Having a history of trauma to the cornea

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Symptoms / Diagnosis

Diagnosis of AK is difficult

Often misdiagnosed

Diagnosis complicated byfrequent occurrence ofsecondary bacterialinfections

Treatment can complicate

diagnosis

Early detection is key

Symptoms

Eye pain

Redness

Blurred vision

Sensitivity to light

Sensation of something ineye

Excessive tearing

(Photo courtesy of Dan B. Jones, M.D.)



CDC Investigation

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Background

Source: CDC, 2007 “Multi-state Outbreak ofAcanthamoeba Keratitis associated with a ContactLens Solution” – IDSA poster

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Methodology

Source: CDC, 2007 “Multi-stateOutbreak of Acanthamoeba Keratitisassociated with a Contact LensSolution”– IDSA poster 10

CDC Findings

Source: CDC, 2007 “Multi-state Outbreak ofAcanthamoeba Keratitis associated with a Contact

Lens Solution” – IDSA poster

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CDC Findings

Source: CDC, 2007 “Multi-stateOutbreak of Acanthamoeba Keratitisassociated with a Contact LensSolution”– IDSA poster

Survey of Ophthalmology Centersfor AK Cases 1999-2006

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CDC Findings

Source: CDC, 2007 “Multi-stateOutbreak of AcanthamoebaKeratitis associated with a ContactLens Solution” – IDSA poster



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CDC Findings

Source: CDC, 2007 “Multi-state Outbreak ofAcanthamoeba Keratitis associated with aContact Lens Solution”– IDSA poster

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CDC Findings

Source: CDC, 2007 “Multi-state Outbreak ofAcanthamoeba Keratitis associated with aContact Lens Solution”– IDSA poster

15

CDC Findings

Source: CDC, 2007 “Multi-stateOutbreak of Acanthamoeba Keratitisassociated with a Contact LensSolution”– IDSA poster

16

Conclusions

Source: CDC, 2007 “Multi-state Outbreak

of Acanthamoeba Keratitis associated witha Contact Lens Solution”– IDSA poster

Florida AK Cases

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Case Identification

Websites/Listservs/Emails:

Public health related

Ophthalmology/optometry

Infection control and clinical microbiology

EpiCom and Merlin

Major ophthalmology centers in Florida



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Florida AK Cases

30 cases initially reported

28 from Bascom Palmer Eye Institute(Miami)

2 from out of state sources

26/30 (86.7%) met case criteria for study

symptom onset on or after 1/1/05

culture confirmed

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Florida AK Cases

Of the 26 confirmed cases meeting the

case definition 21 (80.8%) residents

5 (19.2%) non-residents

Most of the 21 cases found in residentswere from south Florida

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Case Demographics

8 total cases 50% -Male

50% - Female

Race/Ethnicity 1 Black – Non-Hispanic

2 White – Non-Hispanic

3 White – Hispanic

2 Other/Unknown – Hispanic

Age Range 16-61 yrs Median age = 30.5 yrs

Mean age = 33.3 yrs

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Case Identification & Interviews

Case Identification

Each case given a unique IDnumber

State ID number

County of residence

Month/year received bystate

Numerical order of receipt• Ex. 01-0507-02

(Alachua County, May2007, Case#2)

FL cases were also assignedan additional ID number by theCDC

Interviews

Case patient interviewsconducted via telephone

8 out of 21 cases (38.1%)participated in this phase

2 refusals byparents/guardians

2 unable to be located

9 did not respond to

repeated requests toparticipate

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Case Identification, Interviews, &

Specimen Collection

Additional case information also obtained from:

Primary Eye Care Provider Interviews

Treating Ophthalmologist Interviews

Review of Medical Records

Specimens retrieved from patients that completed an interview

Specimens shipped to CDC laboratory for analysis

Five specimens from 3 different patients were shipped to CDC foranalysis

3 CL cases

1 box of CLs

1 bottle of CL solution (AMO Complete Moisture Plus)

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Further Investigation

Control interviews conducted for 3 out of 8 cases in thestudy

Random digit dialed phone list from streets surrounding

reference (case) patient

Specified numbers on each list called until matchedcontrols were found Original goal: 2 controls/case

Modified goal:1 control/case

3 controls recruited out of 329 call attempts



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Summary of Florida AK Cases

History of eye injury

3/8 (37.5%)

Swim w/CLs

3/8 (37.5%)

CL use < 5yrs

3/8 (37.5%)

Topping of Solution

5/8 (62.5%)

Sometimes/never washhands before inserting CLs

1/8 (12.5%)

Used AMO Complete

Moisture Plus

4/8 (50.0%)

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Results of Laboratory specimens

3 CL cases - culture and PCR (-)

1 box of CLs - culture and PCR (-)

1 bottle AMO Complete solution - culture (-) andweakly PCR (+) for Acanthamoeba

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Clinical outcomes

2 - Corneal transplant

2 - Receiving medical Tx

2 - Resolved

2 - Unknown status

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Next Steps

The CDC is currently in the process ofconducting advanced analysis of the datareceived in 2007

Completed findings will be published in thenear future

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Acknowledgments

Dr. Roberta Hammond

Roger Sanderson

Dr. Thomas ColemanAndre Ourso

Dr. Jennifer Verani

AK Team

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References Cabral FM and Cabral G. Acanthamoeba spp. as agents of disease in humans.

2003;16(2)273-307. Clinical Microbiology Reviews.

Centers for Disease Control and Prevention. Acanthamoeba keratitis associated withcontact lenses-United States. MMWR Morb Mortality Wkly Rep. 1986;35(25);405-8.

Centers for Disease Control and Prevention. Acanthamoeba keratitis in soft-contact lenswearers. MMWR Morb Mortality Wkly Rep. 1987;36(25);397-8,403-4.

Centers for Disease Control and Prevention. Update: Fusarium keratitis –United States,2005-2006. MMWR Morb Mortality Wkly Rep. 2006;55(20);563-4.

Centers for Disease Control and Prevention. Acanthamoeba keratitis multiple states,2005-2007. MMWR Morb Mortality Wkly Rep. 2007;56(21);532-4.

Acanthamoeba infection homewww.cdc.gov/ncidod/dpd/parasites/acanthamoeba/index.htm - Accessed 01/23/08

Acanthamoeba keratitis fact sheetwww.cdc.gov/ncidod/dpd/parasites/acanthamoeba/factsht_acanthamoebakeratitis.htm - Accessed 01/23/08

Documents

26 McConnell.kateesha