COMMUNICABLE DISEASE MANUAL POLICIES/PROCEDURES
LEGIONELLOSIS
OBJECTIVE:The control and management of Legionellosis.
DESCRIPTION:An acute bacterial disease with two distinct manifestations: “Legionnaires’ Disease” and “Pontiac Fever”. Both are characterized initially by anorexia, malaise, myalgia and headache. Within a day, there is usually a rapidly rising fever associated with chills. A non-productive cough is common; abdominal pain and diarrhea occur in many patients. In Legionnaires disease, radiograph may show patchy areas of consolidation, which may progress to bilateral involvement and ultimately, to respiratory failure. Pontiac Fever is not associated with pneumonia or death; patients recover spontaneously in 2-5 days without treatment. Incubation period for Legionnaires’ disease is 2-10 days; for Pontiac Fever it is 1-2 days. Legionella species are aerobic bacilli that stain gram-negative. At least 18 different species have been implicated in human disease, but most documented Legionella infections in the United States are caused by the Legionella pneumophila serogroup 1. Legionnaire’s disease is acquired through inhalation of aerosolized water contaminated with L pneumophila. Person-to-person transmission has not been demonstrated. More than 80% of cases are sporadic; the sources of infection may be related to exposure to L pneumophila-contaminated water in the patient's home, workplace, or location of medical therapy or to aerosol-producing devices in public places. Outbreaks have been ascribed to common-source exposure to contaminated cooling towers, evaporative condensers, potable water systems, whirlpool spas, humidifiers, and respiratory therapy equipment. Nosocomial infections occur and often have been traced to a hot water supply. The disease occurs most commonly in elderly and immunocompromised people.
EQUIPMENT:MDSS User Manual (disease specific form will be found in MDSS). Also MDCH Web site at andCDC Web site atdiseasesconditions/az/a.html.
POLICY:Legal Responsibility: Michigan's communicable disease rules of Act No. 368 of the Public Acts of 1978, as amended, being 333.5111 of the Michigan Compiled Laws.
Follow-up time within 72 hours of receiving referral AND ENTER INTO MDSS WITHIN 24 HOURS OF RECEIPT OF REFERRAL.
PROCEDURE:A.Case Investigation
1.Referral received per phone call, laboratory results, or automatically through MDSS.
2.Document all case investigation proceedings.
3.Contact MD and/or client to start process for completing disease specific form in MDSS.
B.Case Definition
1.Legionellosis is associated with two (2) clinically and epidemiologically distinct illnesses: Legionnaires’ disease, which is characterized by fever, myalgia, cough, and clinical orradiographic pneumonia; and Pontiac fever, a milder illness withoutpneumonia. Both lab confirmation AND the diagnosis of pneumonia (clinically or via x-ray) is needed. A positive lab without pneumonia is Pontiac Fever.
C.Lab Criteria for Diagnosis
1.Laboratory Case Confirmation:
One of the following lab requirements must be met:
- Culture: Isolation of any Legionella organism from respiratory secretions, lung tissue, pleural fluid or other normally sterile fluid. The isolation of any serogroup of Legionella is a confirmed case. OR
- Urine antigen: Detection of Legionellapneumophilia serogroup 1 antigen in urine using validated reagents. Urine antigen isNOT the same thing as a culture. OR
- Seroconversion: Fourfold or greater rise in specific serum antibody titer to Legionellapneumophilia serogroup 1 using validated reagents. A fourfold rise in serum antibody to any serogroup besides pneumophilia serogroup 1is aSUSPECTcase.
2.Suspect: Laboratory Criteria:
One of the following lab requirements must be met:
- By seroconversion: Fourfold or greater rise in antibody titer to specific species or serogroups of Legionellaother than L. pneumophilia serogroup 1 (e.g., L. micdadei, L. pneumophilia serogroup 6).
- By seroconversion: Fourfold or greater rise in antibody titer to multiple species of Legionella using pooled antigen and validated reagents.
- By the detection of specific Legionella antigen or staining of the organism in respiratory secretions, lung tissue, or pleural fluid by direct fluorescent antibody (DFA) staining, immunohistochemistry (IHC), or other similar method, using validated reagents.
- By detection of Legionella species by a validated nucleic acid assay.
- Case Classification
1.Suspect: A clinically compatible case that meets at least one of the suspect laboratory criteria.
2.Confirmed: A clinically compatible case that meets at least one of the confirmatory laboratory criteria
3.MDSS Case Investigation Form: The diagnosis must be marked in MDSS under the clinical information section. This is often left unmarked.
4.Travel-associated: a Case that has a history of spending at least one night away from home, either in the same country of residence or abroad, in the 10-14 days before onset of illness. Please give dates, if available.
5.Travel, dental work, hospital exposure should only be noted for the two (2) weeks prior to onset. Please give dates, if available.
6.Please collect information about worksites and/or school. This can be very important in outbreak situations.
E.Control Measures
- Search for additional cases (household, business, etc.) due to infection from a common environmental source. (NOTE: Person-to-person transmission has not been documented.)
2.Educate regarding decontamination of implicated sources and preventive measures (i.e., air conditioning systems, humidifiers, etc.)
3.Refer to Environmental Health for follow-up.
- MDSS Case Report
- Complete case investigation using disease specific form in MDSS
2.Notify CD Supervisor that the case report is ready for review. PHN will be notified if corrections are needed prior to closing case in MDSS.
3.CD Supervisor reviews case for completeness and closes MDSS case report.
RESOURCES:Current Red Book
Current Control of Communicable Diseases Manual
Current disease specific “Fact Sheet”
Websites:
I:\Admin\R JOHANSEN\OPPM\VBCHD\Manuals\CD manual\2012 Communicable Diseases A-Z\LEGIONELLOSIS 5-31-2012.docPage 1 of 4