Guidelines for TB Infection ControlGuidelines for TB Infection Controlin Highin High--HIV Burden SettingsHIV Burden Settings
Paul A. Jensen, PhD, PEPaul A. Jensen, PhD, PE
Centers for Disease Control and PreventionCenters for Disease Control and PreventionCoordinating Center for Infectious DiseasesCoordinating Center for Infectious Diseases
National Center for HIV, STD, and TB PreventionNational Center for HIV, STD, and TB PreventionDivision of Tuberculosis EliminationDivision of Tuberculosis Elimination
Atlanta, Georgia USAAtlanta, Georgia USA
http://www.who.int/gtb/publications/http://www.who.int/gtb/publications/
healthcare/PDF/WHO99healthcare/PDF/WHO99--269.pdf269.pdf
Tuberculosis Infection ControlTuberculosis Infection Controlin the Era ofin the Era of
Expanding HIV Care and TreatmentExpanding HIV Care and Treatment
Addendum to WHOAddendum to WHO Guidelines for the Prevention ofGuidelines for the Prevention ofTuberculosis in Health Care Facilities in ResourceTuberculosis in Health Care Facilities in Resource--
Limited Settings, 1999Limited Settings, 1999
CDC:CDC: Naomi Bock, Paul Jensen, Wanda Walton,Naomi Bock, Paul Jensen, Wanda Walton,MichaelMichael IademarcoIademarco, Bess Miller, Bess Miller
WHO:WHO: Alasdair Reid, PierreAlasdair Reid, Pierre--YvesYves NorvalNorval,,Paul NunnPaul Nunn
IUATLD:IUATLD: RiittaRiitta DlodloDlodlo
Why were Guidelines Developed?Why were Guidelines Developed?
•• People living with HIV/AIDS receivePeople living with HIV/AIDS receivediagnosis, care, treatment, and/or support;diagnosis, care, treatment, and/or support;andand
•• High prevalence of HIV infection, bothHigh prevalence of HIV infection, bothknown and undiagnosed, in settings suchknown and undiagnosed, in settings suchas prisons, jails, other detention centers,as prisons, jails, other detention centers,and drug rehabilitation centers.and drug rehabilitation centers.
Number and size of organisms liberatedNumber and size of organisms liberated“Wells 1934, Duguid 1945, Wells/Riley 1953, et al.”“Wells 1934, Duguid 1945, Wells/Riley 1953, et al.”
Number of Organisms Liberated:Number of Organisms Liberated:TalkingTalking 00 –– 200200
CoughingCoughing 00 –– 3 5003 500
SneezingSneezing 45004500 –– 1 0001 000 000000
Bacteria bearing dropletsBacteria bearing droplets << ØØ100100 µmµm
Size of Droplets (Size of Droplets (FcnFcn of air velocity):of air velocity):SneezeSneeze ~ 300 m/s~ 300 m/s
ØØ100100µµmm ~~ 100 m/s100 m/s
75 %75 % ~~ ØØ1010 µµmm
Jennison [1942]Jennison [1942]
•• LargeLarge droplets fall to ground relatively fast.droplets fall to ground relatively fast.
•• The fate of theThe fate of the SmallerSmaller droplets will depend ondroplets will depend onthe relative humidity of the air in the space.the relative humidity of the air in the space.
•• With evaporation of droplet, “With evaporation of droplet, “crystallisationcrystallisation” will” willoccur, resulting inoccur, resulting in Droplet NucleationDroplet Nucleation, with the, with thenucleus containing the infectiousnucleus containing the infectious organism(sorganism(s).).
•• A 1.0A 1.0 µµmm Droplet NucleusDroplet Nucleus will settle at a rate ofwill settle at a rate of0.0035 cm/s or 3 m in 24 hours!0.0035 cm/s or 3 m in 24 hours!
Fate of DropletsFate of Droplets
What is Infection Control?What is Infection Control?Prevention of TransmissionPrevention of Transmission
Patient to:WorkerPatientVisitor
Visitor to:WorkerPatientVisitor
Worker to:WorkerPatientVisitor
““It may seem a strange principal toIt may seem a strange principal toenunciate as the very firstenunciate as the very first
requirement of a hospital is that itrequirement of a hospital is that itshould do the sick no harm.”should do the sick no harm.”
Florence Nightingale. Notes on Hospitals, 1863Florence Nightingale. Notes on Hospitals, 1863
Hierarchy of Infection ControlsHierarchy of Infection ControlsAdministrative
Environmental
Respiratory
protection
Wor
ker
Patie
ntFa
cilit
y
Hierarchy of Infection ControlsHierarchy of Infection Controls
•• Administrative controlsAdministrative controls to reduce risk ofto reduce risk ofexposure, infection, and disease through policyexposure, infection, and disease through policyand practice;and practice;
•• Environmental (engineering) controlsEnvironmental (engineering) controls totoreduce concentration of infectious bacilli in air inreduce concentration of infectious bacilli in air inareas where contamination of air is likely; andareas where contamination of air is likely; and
•• Respiratory protectionRespiratory protection to protect personnel whoto protect personnel whomust work in environments with contaminated airmust work in environments with contaminated air
Administrative ControlsAdministrative Controls
•• Prevention of droplet nuclei containingPrevention of droplet nuclei containing M.M.tuberculosistuberculosis from being generated;from being generated;
•• Prevention of TB exposure to staff and patients;Prevention of TB exposure to staff and patients;andand
•• Implementation ofImplementation of rapid and recommendedrapid and recommendeddiagnostic investigation and appropriatediagnostic investigation and appropriatetreatmenttreatment for patients and staff suspected orfor patients and staff suspected orknown to have TB.known to have TB.
Administrative Control ProgramAdministrative Control Program
•• Infection control plan (including TB);Infection control plan (including TB);•• Administrative support for procedures in the plan,Administrative support for procedures in the plan,
including quality assurance;including quality assurance;•• Training of staff;Training of staff;•• Education of patients and increasing communityEducation of patients and increasing community
awareness; andawareness; and•• Coordination and communication between theCoordination and communication between the
TB and HIV programs.TB and HIV programs.
What is Ventilation?What is Ventilation?
•• Movement of airMovement of air
•• “Pushing” and/or “pulling” of particles and“Pushing” and/or “pulling” of particles andvaporsvapors
•• Preferably in a controlled mannerPreferably in a controlled manner
Ventilation ControlVentilation Control
•• Types of ventilationTypes of ventilation
–– NaturalNatural
–– LocalLocal
–– GeneralGeneral
11
1010
100100
1,0001,000
00 22 44 66 88 1010
Elapsed Time (hours)Elapsed Time (hours)
Co
lon
yF
orm
ing
Un
its
(CF
Us)
Co
lon
yF
orm
ing
Un
its
(CF
Us)
Position 1Position 2Position 3Position 4Position 5Position 6Position 7Position 8Position 9
Linear
OffOff OnOn
Evaluation of Room Air CleanersEvaluation of Room Air Cleaners
Respiratory ProtectionRespiratory Protection
•• Respirators can protect health workers;Respirators can protect health workers;•• Frequently, they are unavailable in resourceFrequently, they are unavailable in resource--
limited settings;limited settings;•• Respirator use should encouraged in high riskRespirator use should encouraged in high risk
areas of hospitals and referral centers (e.g.,areas of hospitals and referral centers (e.g.,bronchoscopy and MDRbronchoscopy and MDR--TB);TB);
•• A CDC/NIOSHA CDC/NIOSH--certifiedcertified N95N95 (or greater) or CEN(or greater) or CEN--certifiedcertified FFP2FFP2 (or greater) respirator should be(or greater) respirator should beused; andused; and
•• Use of a face mask does not protect health careUse of a face mask does not protect health careworkers, other staff, patients, or visitors againstworkers, other staff, patients, or visitors againstinhalation of TB.inhalation of TB.
Respirator vs. Face MaskRespirator vs. Face Mask
•• RespiratorRespirator has onlyhas onlytiny pores which blocktiny pores which blockdroplet nuclei anddroplet nuclei andrelies on an air tightrelies on an air tightseal around the entireseal around the entireedgeedge
•• Face maskFace mask has largehas largepores and lacks airpores and lacks airtight seal aroundtight seal aroundedgesedges