Detection of Legionella nucleic acid in a lower respiratory tract specimen by polymerase chain reaction (PCR);

Transcription

1 Revisin Dates Case Definitin Reprting Requirements Epidemilgy/Public Health Management March 2018 March 2018 March 2018 Case Definitin Cnfirmed Case Clinical illness (A) with labratry cnfirmatin f infectin: Islatin f Leginella species r detectin f the antigen frm a lwer respiratry tract specimen r a sterile site clinical specimen (B) ; Detectin f Leginella nucleic acid in a lwer respiratry tract specimen by plymerase chain reactin (PCR); Sercnversin r significant (furfld r greater) rise in Leginella sp. IgG antibdy titre between acute and cnvalescent sera; Detectin f L. pneumphila antigen in urine (C). Prbable Case Clinical illness (A) with ne f the fllwing: Single IgG antibdy titre t Leginella sp. f >1:128; Epidemilgically linked t a cnfirmed case. (A) cmprises tw distinct illnesses: Leginnaires disease characterized by myalgia, fever, cugh, and pneumnia and Pntiac fever, a milder illness withut pneumnia. (B) Refer t the PrvLab Guide t Services fr current specimen cllectin requirements. (C) Crss-reactins have been demnstrated between urinary antigens f several L. pneumphila grups. Antigen may be excreted fr mnths after acute infectin. 1 f 7

2 Reprting Requirements 1. Physicians, Health Practitiners and Others Physicians, health practitiners and thers shall ntify the Medical Officer f Health (MOH) (r designate) f the zne, f all cnfirmed and prbable cases in the prescribed frm by mail, fax r electrnic transfer within 48 hurs (tw business days). 2. Labratries All labratries shall reprt all psitive labratry results by mail, fax r electrnic transfer within 48 hurs (tw business days) t the: Chief Medical Officer f Health (CMOH) (r designate), and MOH (r designate) f the zne 3. Alberta Health Services, First Natins and Inuit Health Branch The MOH (r designate) f the zne where the case currently resides shall frward the initial Ntifiable Disease Reprt (NDR) f all cnfirmed and prbable cases t the CMOH (r designate) within tw weeks f ntificatin and the final NDR (amendment) within fur weeks f ntificatin. Fr ut-f-prvince and ut-f-cuntry reprts, the fllwing infrmatin shuld be frwarded t the CMOH (r designate) by phne, fax r electrnic transfer within 48 hurs (tw business days): name, date f birth, ut-f-prvince health care number, ut-f-prvince address and phne number, psitive labratry reprt, and ther relevant clinical / epidemilgical infrmatin Gvernment f Alberta 2 f 7

3 Etilgy is caused by Leginella bacteria, which are gram-negative bacilli. (1) There are at least 20 species f Leginella that cause disease in humans with the mst cmmn type being L. pneumphila sergrup 1 that causes the majrity f clinical disease. Clinical Presentatin is an acute bacterial disease with tw currently recgnized, distinct manifestatins: Leginnaires disease and Pntiac fever. (2) Leginnaires disease is the mre severe frm f characterized by pneumnia and prgressive respiratry distress, which may lead t death. Pneumnia caused by Leginella cannt be accurately differentiated frm pneumnia caused by ther rganisms. (3) Other symptms assciated with the infectin include, cugh, fever, chills, myalgia, gastrintestinal tract, renal and central nervus system manifestatins. (1,4) Case-fatality rates are arund 15%, even thugh treatment and diagnstics have been imprved. (2) Pntiac fever is a milder febrile illness withut pneumnia. Deaths due t Pntiac Fever have nt been reprted. Symptms include abrupt nset f influenza-like illness. (1) Pntiac fever is mst ften seen as part f a cluster r during utbreaks. (1,5) Reservir Leginella bacteria are ubiquitus in nature, particularly in aquatic envirnments. (1,2) Temperatures f C, stagnant water, presence f ciliate prtzans and amebas, crrsin and bifilms are sme f the factrs that supprt grwth f Leginella bacteria. Scale, which is the build-up f sediment r minerals (calcium r magnesium salts) in r n water distributin systems, husehld plumbing r water reservirs als cntributes t grwth f Leginella. Outbreaks and spradic cases have been linked t: ht and cld water systems, air cnditining cling twers and evaprative cndensers, humidifiers fr fd display cabinets r hme humidifiers, whirlpl spas/natural pls/thermal springs, respiratry therapy devices, decrative funtains/sprinklers, garden hses, ptable water systems, vehicle washes, mist prducing devices, water-cled machine tls. (1,4) Transmissin Leginella bacteria can be transmitted frm water t humans by the inhalatin f cntaminated aersls and by aspiratin. (1) Persn-t-persn transmissin des nt usually ccur but may be pssible in rare cases. (6) Incubatin Perid The incubatin perid has a range f 2-14 days, usually averages 5-6 days. (4,7,8) Sme cases may have an extended incubatin perid up t 19 days. Pntiac fever has a much shrter incubatin perid with a range f 5-72 hurs, but mst ften hurs Gvernment f Alberta 3 f 7

4 Perid f Cmmunicability Unknwn; persn-t-persn transmissin is rare. (6) Hst Susceptibility The chances f develping depends n hst factrs, prductin and disseminatin f aersls, cncentratin f Leginella bacteria in the water surce, and the virulence f the particular strain f Leginella. (9) Individual risk factrs fr acquiring disease include: Older age grup (>50yrs), Male gender, Heavy smking r high alchl intake, Chrnic disease such as diabetes, lung, kidney r liver disease Immuncmprmising disrders r immunsuppressant medicatins Heavy smking and Risk factrs fr expsure t Leginella include: Recent travel, with an vernight stay utside f the hme, including a stay in a healthcare facility; Expsure t ht tubs; and Expsure t settings where the plumbing has had recent repairs r maintenance wrk. Health care assciated infectins can ccur therefre, Leginnaires disease shuld be cnsidered as part f the differential diagnsis in patients wh develp pneumnia during r after their hspitalizatin. Transplant patients, thse wh are immuncmprmised r with certain chrnic underlying health cnditins are at highest risk f acquiring nscmial Leginella infectin. is rare in children and if infectin des ccur, symptms are usually mild, asymptmatic and may g unrecgnized. (1) Incidence in Alberta Between 2000 and 2016 there were 106 cases f reprted in Alberta. (10) The majrity f thse cases were acquired lcally. In the summer/fall f 2012, there was a reprted increase in lcally-acquired cases. Intense public health investigatins did nt reveal a cmmn nscmial r residential surce linking the cases. Annual case cunts may be accessed thrugh the Interactive Health Data Applicatin (IHDA) at: Public Health Management Diagnsis Labratry testing fr the detectin f Leginella may include urine antigen testing, serum antibdy testing, respiratry culture and ther mlecular methds (e.g. PCR). The gld standard fr diagnsis is respiratry culture, which allws the identificatin f species and subgrups. Urine antigen testing can als be used, hwever it is nly highly sensitive and specific fr L. pneumphila sergrup 1. (1) Refer t PrvLab Guide t Services fr current specimen cllectin recmmendatins. (11) Key Investigatin Cnfirm the diagnsis. Other causes f pneumnia, such as influenza, pneumcccal r streptcccal disease, shuld be ruled ut, if pssible. Assess fr any underlying health cnditins. Determine where the case may have been expsed, taking int cnsideratin the incubatin perid, reservir and mde f transmissin, including: Gvernment f Alberta 4 f 7

5 Detailed travel histry including names f htels, resrts, etc. during the 14 days prir t symptm nset. Histry f relevant expsure, particularly t air cnditiners, humidifiers and aerslized water, e.g., ht tubs, jacuzzis, funtains, plant mister s, grcery stres r cling statins within the 14 days prir t symptm nset. Assess if there have been any changes t the main surce f water in the primary residence r travel settings, including general cnstructin, plumbing prjects, water main breaks, water line wrk r changes in water temperature in the last 2-4 weeks. Cnduct an epidemilgic and envirnmental assessment in cnsultatin with apprpriate Envirnmental Public Health and/r facility-based Infectin Preventin and Cntrl (IPC) persnnel t help determine whether envirnmental sampling is indicated as part f the leginella investigatin. If indicated, attempt t cllect water samples frm ptential surces f expsure that may be cntaminated and submit t PrvLab fr examinatin (See PrvLab Guide t Services fr current water sample cllectin requirements). Determine if expsure may have ccurred in a cmmunity health care setting such as a dctr r dentist ffice/clinic, lng-term care facility, assisted living r senir living facility r nursing hme. Determine if persn was a patient, resident, visitr r wrker at the time f expsure in the particular setting. If hspitalized, attempt t determine if the expsure was in the cmmunity r nscmial. Classificatin f nscmial expsure: Definite nscmial expsure is defined as: a cnfirmed case f Leginella hspitalized cntinuusly fr 14 days befre the nset f symptms. Pssible nscmial expsure is defined as: a cnfirmed case f Leginella wh develped symptms 2-13 days after hspital admissin. Case Management Rutine practices are recmmended fr hspitalized patients. Supprtive treatment. Treatment f a Case Cnsultatin with an Infectius Diseases Specialist is recmmended. Treatment f Leginnaires disease with apprpriate antibitics is recmmended. Cases with Pntiac fever generally recver spntaneusly in tw t five days withut treatment. (1) Management f Cntacts Persn-t-persn transmissin des nt usually ccur, hwever, symptmatic and asymptmatic cntacts shuld be investigated if a cmmn surce is suspected (e.g. cling twer). Management f Outbreaks A Leginella utbreak is defined as tw r mre cnfirmed cases linked by time and space. An utbreak may be declared by the zne MOH in the manner determined mst apprpriate by the MOH in cnsultatin with Alberta Health. Fr the purpses f public messaging, the term "utbreak" need nt be used in rder t apply the utbreak plicy. Outbreak measures include but are nt limited t the fllwing: Cnduct an epidemilgic and envirnmental assessment and identify surce f expsure Gvernment f Alberta 5 f 7

6 Attempt t cllect water samples frm ptential surces f expsure that may be cntaminated and submit t PrvLab fr examinatin (See PrvLab Guide t Services fr current water sample cllectin requirements). Implement measures t prevent further expsure t identified surce f expsure. Review maintenance lgs fr water systems fr surces f expsure. Review and implement decntaminatin prcedures f water systems that are cntaminated. NOTE: Travel-related Leginella utbreaks can smetimes be difficult t identify especially if cases return hme prir t symptm nset. Preventive Measures Prper maintenance f water systems (especially artificial water surces) in which Leginella grw is the key t preventing infectin with Leginella. (12) General recmmendatins fr preventin f infectin include the fllwing: The elderly and thse with immuncmprmising cnditins shuld avid high risk areas such as whirlpl spas. (13) Mist-prducing devices such as humidifiers, ht tubs, shwer heads and whirlpl bathtubs/jacuzzi shuld be cleaned and disinfected as per manufacturer instructins. (14) Hme water heaters shuld be kept a minimum temperature f 60 C, hwever in rder t prevent scalding, the temperature at the tap shuld be n higher than 49 C. (14) Tap water shuld nt be used fr respiratry therapy devices. (2) Instead, use sterile water in the device tank and fr rinsing any type f equipment used fr respiratry tract treatment. Keep ht and cld water systems clean and reduce stagnatin by flushing unused taps (9) Cling twers shuld be well maintained. Maintenance, testing and disinfectin f watercling twers is a cmplex prcess and shuld be dne by persns with expertise in this area Gvernment f Alberta 6 f 7

7 References 1. American Academy f Pediatrics. Leginella pneumphila infectins. In: Kimberlin DW., Brady MT., Jacksn MA., Lng SS, editrs. Red Bk: 2015 Reprt f the Cmmittee n Infectius Diseases. 30th editi. Elk Grve Village, IL: America Academy f Pediatrics; p Heymann D, editr. Cntrl f Cmmunicable Diseases Manual. 20th ed. Washingtn, D.C.: American Public Health Assciatin; Edelstein PH, Ry CR. Leginnaires Disease and Pntiac Fever. In: Bennett JE., Dlin R., Blaser MJ., editrs. Mandell, Duglas & Bennett s Principles and Practice f Infectius Diseases. Eighth. Philadelphia, P.A.: Elsevier Saunders; p Public Health Ontari. Mnthly Infectius Diseases Surveillance Reprt. 2015;4(7):1 9. Available frm: Infectius-Diseases-Surveillance-Reprt.aspx 5. Phin N, Parry-Frd F, Harrisn T, Stagg HR, Zhang N, Kumar K, et al. Epidemilgy and clinical management f Leginnaires disease. Lancet Infect Dis [Internet] Oct [cited 2017 Apr 5];14(10): Available frm: linkinghub.elsevier.cm/retrieve/pii/s Crreia AM, Ferreira JS, Brges V, Nunes A, Gmes B, Capuch R, et al. Prbable Persn-t- Persn Transmissin f Leginnaires Disease. N Engl J Med [Internet]. Massachusetts Medical Sciety; 2016 Feb 4 [cited 2017 Apr 5];374(5): Available frm: 7. Centers fr Disease Cntrl and Preventin. Leginella (Leginnaires Disease and Pntiac Fever) [Internet] [cited 2017 Apr 5]. Available frm: 8. Natinal F/T/P Wrking Grup. Leginella Telecnference: Incubatin perid discussin Wrld Health Orgranizatin (WHO). [Internet]. Wrld Health Organizatin; 2016 [cited 2017 Apr 5]. Available frm: Alberta Health. Cmmunicable Disease Reprting System (CDRS). Edmntn, AB; The Prvincial Labratry fr Public Health (PrvLab). Guide t Services [Internet] [cited 2017 Apr 5]. Available frm: Cunha BA, Burill A, Buza E. Leginnaires disease. Lancet [Internet]. Elsevier Ltd; 2016;387(10016): Available frm: dx.di.rg/ /s (15) Public Health Agency f Canada. Infectin Cntrl Guideline: Healthcare-Assciated Pneumnia [Internet] [cited 2017 Apr 5]. Available frm: publicatins.gc.ca/cllectins/cllectin_2012/aspc-phac/hp eng.pdf 14. Public Health Agency f Canada (PHAC). Leginella - Infectius Diseases [Internet] [cited 2017 Apr 5]. Available frm: Gvernment f Alberta 7 f 7