Transcript 結核病之感染管制政策 衛生署 疾病管制局 中區傳染病防治醫療網 王任賢 指揮官

結核病之感染管制政策
衛生署 疾病管制局
中區傳染病防治醫療網
王任賢 指揮官
如何避免結核病在醫院內散播
• 行政上之作為
• 醫療硬體環境之作為
• 執行醫療業務之作為（個人防護）
行政上的作為
• Organizational Policies and Procedures
• Examples
– TST screening programs（篩出感染者）
– Symptom screening to detect patients who have TB
disease （篩出有病者，例如咳嗽監測）
– Isolate patients with infectious TB disease from
other patients （隔離傳染性結核病患）
• Conduct diagnostic evaluation of such patients
– Treat patients who likely have TB disease （治療）
• TB suspects, contacts, risk groups
執行醫療業務及行政上之作為
•
•
•
•
完善的院內感染管制計畫
醫療主管支持院內感染管制計畫
醫療人員及病患之教育
各項結核病管控措施必須有良好的搭配
篩出感染者:
Tuberculin skin test
Tuberculin preparation
• Old tuberculin (OT)
1908: Robert Koch produced in Germany
filtered heat-sterilized TB bacilli
• Purified protein derivative (PPD)
1939: Florence Siebert in Philadelphia
precipitate prepared from OT
reference standard PPD-S
(Siebert’s Lot 49608)
3 dosage strength: 1 TU, 5 TU, 250 TU
Mantoux test
•
•
•
Inject intradermally 0.1 ml
of 5TU PPD tuberculin
Produce wheal 6 mm to 10
mm in diameter
Represent DTH
Reading of Mantoux test
Read reaction 48-72 hours
after injection
Measure only induration
Record reaction in mm
Distribution of PPD: Alaskans
Distribution of PPD:
white Navy recruits
Distribution of PPD: New York
Classifying the tuberculin reaction
>5 mm is classified as positive in
• HIV-positive persons
• Recent contacts of TB case
• Persons with fibrotic changes on CXR
consistent with old healed TB
• Patients with organ transplants and other
immunosuppressed patients
Classifying the tuberculin reaction
>10 mm is classified as positive in
• Recent arrivals from high-prevalence countries
• Injection drug users
• Residents and employees of high-risk settings
• Mycobacteriology laboratory personnel
• Persons with clinical conditions that place
them at high risk
• Children <4 years, or children and adolescents
exposed to adults in high-risk categories
Classifying the tuberculin reaction
>15 mm is classified as positive in
• Persons with no known risk factors for
TB
Occupational exposure to TB
Cutoff value depend on
• Risk factors for TB
• Prevalence of TB in the facility
Factors that may affect the TST


False positive
Nontuberculous mycobacteria
BCG vaccination
False negative
Anergy
Recent TB infection
Very young age (< 6 months old)
Live-virus vaccination
Overwhelming TB disease
Boosting
• Some people with LTBI may have negative
skin test reaction when tested years after
infection
• Initial skin test may stimulate (boost) ability to
react to tuberculin
• Positive reactions to subsequent tests may be
misinterpreted as a new infection
Two-Step Testing
Use two-step testing for initial skin testing of
adults who will be retested within 1-3 weeks
• If first test (+), consider the person infected
• If first test (-), give second test 1-3 weeks
later
• If second test (+), consider person infected
• If second test (-), consider person uninfected
篩出有病者:
咳嗽監測
全院員工胸部X光檢查
醫院之咳嗽偵測機制
• Cough officer之設立
由病房護理長擔任
每日回報咳嗽已經五天的病患
以警語提醒醫師要為病患作CXR、送
痰檢、作結核病防護
(五歲以下兒科病患除外)
全院員工每年胸部X光檢查
VS
高危險員工每年胸部X光檢查
Identify Suspected or Confirmed
TB Cases
• Know the current case definition and criteria
for the classification of suspected and
confirmed TB cases
• Gather information to verify cases reported
routinely to the TB program
Confirmed Case
• Isolation of M.tb complex on culture
• Demonstration of M.tb by nucleic acid
amplification test
• Demonstration of AFB when culture
cannot be obtained, ie post mortem
setting
Clinical Case
• Positive tuberculin skin test +
• Signs or symptoms compatible with TB such
as fever, night sweats, cough, weight loss,
hemoptysis or an abnormal CXR +
• Improvement shown with treatment on antiTB meds +
• Completed medical evaluation
TB Classification System
Class
Type
Description
0
No exposure to TB
Not infected
No history of exposure, negative reaction to tuberculin skin test
1
Exposure to TB
No evidence of infection
History of exposure, negative reaction to a tuberculin skin test
given at least 10 weeks after exposure
2
TB infection
No TB disease
Positive reaction to the tuberculin skin test, negative smears and
cultures (if done), no clinical or x-ray evidence of current TB
disease
3
Current TB disease
Positive culture for M. tuberculosis (if done), or A positive reaction
to the tuberculin skin test and clinical or x-ray evidence of current
TB disease.
4
Previous TB Disease (not
current)
Medical history of TB disease, or
Abnormal but stable x-ray findings for a person who has a positive
reaction to the tuberculin skin test, negative smears and cultures
(if done), and no clinical or x-ray evidence of current disease
5
TB suspected
Signs and symptoms of TB disease, but evaluation is not complete
隔離傳染性結核病患:
誰有傳染性？
Risk of TB infection and disease
among exposed individuals
No infection
70%
Exposure
(close contact)
Infection
~30%
Early progression
(recent TB<2 years)
5-10%
Late progression
(reactivation
TB)
Containment
5%
90-95%
Continued
containment
85-90%
How is tuberculosis transmitted？
Respiratory maneuvers &
elaboration of particles
• Speaking: 0-210 particles
• Coughing: 0-3,500 particles
• Sneezing: 4,500-1,000,000 particles
Duguid J. Edinburgh Med J 1945;52:385
Droplet-nucleus transmission
• Sneezing droplet: 10 mm
• Droplet nucleus: 1-10 mm
settle at a rate of 0.2 mm/sec
8 mm size 10% reach alveoli
2-3 mm size 40% reach alveoli
Baltimore Veterans
Administration Hospital Pilot
Ward Experience
Riley R. and Wells W. 19561961
Materials and Methods
• 第一階段：在六間負壓TB病房的出風口外放置
一動物養殖籠，裡面飼養150-240隻天竺鼠實
驗用天竺鼠均先經30天檢疫且TST(-)
實驗後天竺鼠均接受系列之TST，TST若轉陽
性則必須接受解剖
• 第二階段：負壓房間的出風口外分成兩股，一
股接受UV照射，另一股則無。感染的天竺鼠
並依抗藥性模式而判定被何人傳染。
結
果 (一)
• 天竺鼠平均感染時間為10日
3
• TB的感染劑量為1 in 11,000-12,500 ft of air
• 14/63隻感染的天竺鼠是被一TB laryngitis的人
所傳染，此人之住院日數只佔總人日數的1%
• 130住院病人中，其中8人傳給了46%的天竺鼠
• 未治療病患的傳染力是治療病患的10-50倍
• 非抗藥性結核的傳染力是抗藥性結核的4-8倍
結
果 (二)
• 絕大多數新感染結核病的天竺鼠解剖時，肺部
均只有一個tubercle，表示都只感染到一隻結
核菌
• 也有些新感染結核病的天竺鼠解剖時，肺部並
沒有任何發炎反應
• 經過UV處理的空氣不會感染任何天竺鼠
Epidemic in Arkansas
industrial school
• 在阿肯色工業學校曾有二位學生有開放
性肺結核，對其接觸者做調查發現與患
者同一唱詩班的學員有最高的被傳染率
• 結論：rapidly vibrating vocal cords最容
易產生droplet nuclei
NEJM 1965;272:714-7
U.S. Navy Richard E. Byrd
study
• 1966年9月美國軍艦Richard E. Byrd號出
現了第一例開放性肺結核案例，病患已
咳了6個月，CXR開了一個5公分的洞
• 308位船員接受了完整的流行病學調查
Arch Environ Health 1968;16:4-6
Arch Environ Health 1968;16:26-35
結
果
• 在308位船員中
45% (139人) TST轉為陽性
2.2% (7人) 胸部X光發現肺結核病變
• Compartment 1(index case所睡的地方)
全部66人，6人發病、47人陽轉
共80% (6+47/66)的人被傳染
• Compartment 2(與C1同一空調出口)
共53% (43/81) 陽轉，多睡在出風口附近
＊
Transmission rate according to
index case’s sputum smear status
Study
Index case sputum status
Sm +/Cu +
Sm -/Cu +
England 1954
65%
27%
Canada 1954
45%
26%
Netherland 1967-9
5%
5%
＊
Defined as TST return to positive
Am Rev Tuberc 1954;69:724-32
Am Rev Respir Dis 1964;90:707-20
Bull Int Un Ag Tuberc 1975;50:107-21
＊
Transmission rate according to index
case’s sputum smear status & type of
contact
Study
Household
Causal
＊
Index case sputum status
Sm +/Cu +
Sm -/Cu +
20.2%
1.1%
3.7%
0.2%
Defined as TST return to positive
Am Rev Respir Dis 1964;90:707-20
Bull Int Un Ag Tuberc 1975;50:107-21
Develop active TB according to index
case’s sputum smear status
Study
Index case sputum status
Sm +/Cu +
Sm -/Cu +
Close, age 0-14 y
38%
18%
age 15-29 y
11%
1%
Causal, age 0-14 y
24%
18%
age 15-29 y
6%
3%
Am Rev Respir Dis 1964;90:707-20
Bull Int Un Ag Tuberc 1975;50:107-21
Transmission from
nonpulmonary source
• Cutaneous TB
• Soft tissue TB
案 例
• 67歲的男性1985年1月8日因left hip pain住院。
1月12日接受外科手術，證實為TB並開始吃
藥，但每天都必須以高壓沖洗傷口。
4/5為病患開刀的人後來得到TB
6/20 MICU的staff 後來得到TB
28/33 病房的staff 後來得到TB
Infectiousness vs. Noninfectiousness of TB
Factors Associated with
Infectiousness
Factors Associated with
Noninfectiousness
TB of the lungs or larynx
Most extrapulmonary TB
Cavity in the lung
No cavity in the lung
Cough or cough-inducing
procedures
No cough or cough-inducing
procedures
Patient not covering mouth when
coughing
Patient covering mouth when
coughing
Acid-fast bacilli on sputum smear
No acid-fast bacilli on sputum
smear
Not receiving adequate treatment
Receiving adequate treatment
(dose and time)
肺結核病患何時具有傳染力？
• Persons with active TB disease of the lungs and
throat are considered infectious if they:
– Are coughing
– Are undergoing cough-inducing or aerosolgenerating procedures
– Have sputum smears positive for acid-fast bacilli
and are not receiving therapy
– Have just started TB therapy
– Have poor clinical response to therapy
肺結核的傳染力與何種因素有關？
• The infectiousness is directly related to the:
– number of tubercle bacilli the TB patient releases
into the air
– clinical characteristics of the patient’s TB disease
– patient’s response to therapy
• Infectiousness declines rapidly after adequate
treatment is started
何種肺結核病患不具傳染力？
Patients with TB disease are considered noninfectious if they meet all of the following criteria:
 They are on adequate therapy for at least 2 weeks
 They have had a significant positive clinical
response to therapy
 They have had 3 consecutive negative specimen
smear results
傳染性肺結核病患何種狀況下可
判定不具傳染力？
Must meet all of the following criteria:
 Receiving appropriate treatment
• Dose and time, depending on regimen chosen
• Sensitivity results show treatment is adequate
 Shows improved symptoms and/or chest x-ray
 Has three negative sputum smears
• Collected on different days
年輕人肺結核的傳染力
• Less likely than adults and adolescents to be
infectious
• Thought to have smaller bacterial load
• Not effective coughers
– Less likely to produce sputum or expel
bacteria into the air
治療疑似、確認之結核病患
結核病的治療有那些新的訊息？(1)




治療成功與否的關鍵在醫師的處方，不能
全把責任推給病人
病患的治療強調DOTS
對於治療的模式出現了很多新的證據，對
於評斷何種治療方法最有效？相當有幫助
藥物治療兩個月後痰培養的結果成為有效
預測病患是否會再發的重要依據
結核病的治療有那些新的訊息？(2)



即使是藥物敏感性之結核病人，若有造
成再發之因子存在，應接受extend
treatment
正確定位抗結核新藥如rifabutin,
rifapentine, 及fluoroquinolones的角色
對於正確給藥、合併用藥、副作用之處
置、及藥物相互作用均有了較新的準則
結核病的治療有那些新的訊息？(3)
•是否完治決定於是否在一定期間內服完所有的藥
物
•特殊治療狀況之準則制定:
– HIV/AIDS
– Children
– Extrapulmonary TB
– Culture-negative TB
– Pregnancy and breast feeding
– Hepatic and renal disease
結核病感控之硬體設施
• Reduce/dilute droplet nuclei containing M.
tuberculosis in the air
• Reconfigure waiting areas, exam rooms to
maximize controlled natural ventilation
• Propeller and exhaust fans
Engineering Controls
• Examples
– Ventilation
– HEPA filters
– Ultraviolet germicidal irradiation
結核病之個人防護
CDC界定之結核病高危險傳染
場所
•
•
•
•
•
Health care settings
Correctional institutions
Homeless shelters
Long-term care facilities for the elderly
Drug treatment centers
高傳染風險之行為
• Characterized by potential to generate
airborne secretions
• Aerosolized medication treatment
• Bronchoscopy
• Sputum induction
• Endotracheal intubation and suctioning
• Autopsies
何時該做結核病個人防護？
• When to Use:
– In TB isolation rooms
– In rooms where cough-inducing
procedures are done
– In ambulances and other vehicles
transporting infectious TB patients
– In homes of infectious TB patients
結核病個人防護設備之品管
• Where respirators are required:
- Employers must provide and make sure
employees use NIOSH-approved high-efficiency
particulate respirators
- Employers must have a respiratory protection
program in accordance with OSHA requirements
- Respirators must be “fit-tested” annually
with employee
- Respirators must be “fit-checked” by employee
prior to each use
接觸者調查與追蹤
•
Locate and screen close contacts of active
case(s)
–
–
–
Close contacts include:
• Spouse/significant others
• Individuals sharing households, berthing
compartments, and workspaces
Screen close contacts with TST immediately and
in three months
Evaluate converters for active TB
人口密集機構之結核病感染管制
政策
• Includes facilities such as:
– Nursing homes, correctional facilities, homeless
shelters, and drug treatment centers
• Goal
–
–
–
–
–
Detect TB disease early
Arrange for isolation of persons with TB disease
Treat persons suspected of TB disease
Identify unrecognized transmission
Identify potentially undetected cases
傳染性結核病患居家注意事項
• Instruct symptomatic patients to cover mouth
and nose when coughing/sneezing
– Disposal of tissues, etc.
• Isolation instructions
– No visitors, work school, etc.
– Wear mask when leaving home
– Open windows and blinds for ventilation
and sunlight
公衛單位在結核病院感上所扮
演的角色
•
•
•
•
Work closely with health care facilities
Conduct contact investigations
Coordinate follow-up care
Assist other facilities in screening,
surveillance, outbreak investigations,
and other aspects of TB infection control
公衛訪視員在家訪時該注意的
事項
• Wear personal respirator when visiting the
home of an infectious TB patient or when
transporting an infectious TB patient in a
vehicle
• Collect sputum, if necessary, in a wellventilated area, away from other household
members
• Participate in a TB screening program
懇請賜教