Intensified TB case-finding: still wide open to questions and answers

100 %
0 %
Information about Intensified TB case-finding: still wide open to questions and answers

Published on December 22, 2007

Author: blueash

Source: slideshare.net

Description

Intensified TB case-finding: still wide open to questions and answers

Intensified TB case-finding: still wide open to questions and answers Dr Liz Corbett Bloomsbury Wellcome Trust Centre & Clinical Research Unit, London School Hygiene Tropical Medicine Biomedical Research & Training Institute, Harare

Pre-DOTS era ICF widely used in all continents Mass mini-radiographs and household enquiries Diagnosis and treatment +/- sanatoria Still used in some settings today Use associated with declining TB incidence rates in many settings Not formally evaluated as an isolated intervention

ICF widely used in all continents

Mass mini-radiographs and household enquiries

Diagnosis and treatment +/- sanatoria

Still used in some settings today

Use associated with declining TB incidence rates in many settings

Not formally evaluated as an isolated intervention

Kolin 1961 – 1972 Kolin study 5 rounds of MMR Point prevalence of s+ TB fell from 233 to 56 per 100k Incidence of s+ TB fell from 142 to 52 per 100k per year Effective TB treatment introduced + BCG 72% of all cases detected between MMR rounds through passive CFT More effective to focus on effective treatment of cases presenting passively

1961 – 1972 Kolin study

5 rounds of MMR

Point prevalence of s+ TB fell from 233 to 56 per 100k

Incidence of s+ TB fell from 142 to 52 per 100k per year

Effective TB treatment introduced + BCG

72% of all cases detected between MMR rounds through passive CFT

More effective to focus on effective treatment of cases presenting passively

India Tumkur District prevalence survey 1960s (TST and CXR) No TB treatment programme Follow-up investigation for symptoms (?delay) 70% of smear-positive patients aware of symptoms 50% had already sought care Bangalore CXR versus CXR plus symptom screen Symptoms added little to CXR Symptoms alone identified 70% culture-positive TB patients Banerji D, Anderson S. A sociological study of awareness of symptoms among persons with pulmonary tuberculosis. Bull Wld Hlth Org 1963; 29:665-683. Gothi GD, et al. Estimation of prevalence of bacillary tuberculosis on basis of chest x-ray and-or symptomatic screening. Indian J Med Res 1976; 64(8):1150-1159.

Tumkur District prevalence survey 1960s (TST and CXR)

No TB treatment programme

Follow-up investigation for symptoms (?delay)

70% of smear-positive patients aware of symptoms

50% had already sought care

Bangalore

CXR versus CXR plus symptom screen

Symptoms added little to CXR

Symptoms alone identified 70% culture-positive TB patients

Kenya Case-finding studies in 1970s and 1980s House-to-house surveys most effective 80% of cases had been to clinic with symptoms Distance to clinic Interview of village elders ineffective Mothers asked to refer anyone with symptoms in their household High yield in those who attended Low population impact (4% all cases)

Case-finding studies in 1970s and 1980s

House-to-house surveys most effective

80% of cases had been to clinic with symptoms

Distance to clinic

Interview of village elders ineffective

Mothers asked to refer anyone with symptoms in their household

High yield in those who attended

Low population impact (4% all cases)

Korea Routine use of “school leavers” for door-to-door enquiry Each employee covered 10,000 pop Over 50% of cases picked up this way during 1970s

Routine use of “school leavers” for door-to-door enquiry

Each employee covered 10,000 pop

Over 50% of cases picked up this way during 1970s

Community-wide p reventive therapy: Bethel ARI (%) & incidence rates / 100 000 pop p.a. 0% 5% 10% 15% 20% 25% 30% 1954 1957 1960 1963 1966 1969 1972 500 1,000 1,500 2,000 2,500 3,000 ARI TB incidence Passive & intensified CFT & BCG INH RCT: 42% pop INH 12mos INH all residents

Other studies Toman (1976) 75% of cases self-presenting in countries covered by MMR programmes Netherlands – annual CXR (2.5 million adults) 15% of s+ and 25% of c+ TB detected through MMR Expensive, not cost-effective Assumes equal public health impact of ACF & PCF pick-up Toman K. Mass radiography in tuberculosis-control. Who Chronicle 1976; 30(2):51-57

Toman (1976)

75% of cases self-presenting in countries covered by MMR programmes

Netherlands – annual CXR (2.5 million adults)

15% of s+ and 25% of c+ TB detected through MMR

Expensive, not cost-effective

Assumes equal public health impact of ACF & PCF pick-up

Fate of pulmonary TB treated under routine conditions High rates of treatment failure and recurrence Increasing recognition of the importance of adequate treatment First priorities: Effective diagnosis in patients presenting passively Effective treatment of those presenting passively Don’t waste money and risk overwhelming health systems with ICF until these basics are in place  DOTS

High rates of treatment failure and recurrence

Increasing recognition of the importance of adequate treatment

First priorities:

Effective diagnosis in patients presenting passively

Effective treatment of those presenting passively

Don’t waste money and risk overwhelming health systems with ICF until these basics are in place  DOTS

ICF in the DOTS era Low case-detection a major factor limiting TB control Patients with symptoms cannot access investigations Marginalised populations Not all TB is highly symptomatic HIV-associated TB Driving up global incidence rates High prevalence of active TB in HIV care settings High mortality rates Modeling the impact of better case-finding Time ripe to reconsider ICF

Low case-detection a major factor limiting TB control

Patients with symptoms cannot access investigations

Marginalised populations

Not all TB is highly symptomatic

HIV-associated TB

Driving up global incidence rates

High prevalence of active TB in HIV care settings

High mortality rates

Modeling the impact of better case-finding

Time ripe to reconsider ICF

ICF goals Reduce morbidity and mortality More intensive case-finding leads to fewer TB deaths and less severe post-TB complications Focus on those most at risk of severe morbidity Reduce TB transmission General community Institutional settings Marginalised populations Increase case-finding Target high risk groups Community-wide approach

Reduce morbidity and mortality

More intensive case-finding leads to fewer TB deaths and less severe post-TB complications

Focus on those most at risk of severe morbidity

Reduce TB transmission

General community

Institutional settings

Marginalised populations

Increase case-finding

Target high risk groups

Community-wide approach

ICF challenges Poor treatment outcomes Patients detected through ICF unwilling to be treated ICF in settings of high primary MDR-TB Diagnostic approach Active versus inactive TB Relatively low % smear-positive cases Choice of screening and diagnostic tests Illnesses other than TB OIs & HIV itself Overwhelm the health system

Poor treatment outcomes

Patients detected through ICF unwilling to be treated

ICF in settings of high primary MDR-TB

Diagnostic approach

Active versus inactive TB

Relatively low % smear-positive cases

Choice of screening and diagnostic tests

Illnesses other than TB

OIs & HIV itself

Overwhelm the health system

Cohort study Prevalence study snap shot in time Time (person years) Incidence and prevalence linked by duration of disease

Prevalent TB disease High ratio of prevalent: incident disease among HIV-ves See next slide Risk groups for prevalent TB disease Household contacts Homeless IDU VCT attenders Home based care Congregate settings: prisons and miners Old age and male sex

High ratio of prevalent: incident disease among HIV-ves

See next slide

Risk groups for prevalent TB disease

Household contacts

Homeless

IDU

VCT attenders

Home based care

Congregate settings: prisons and miners

Old age and male sex

Prevalence: incidence

Can have prolonged HIV/TB with minimal symptoms: duration of smr+ before diagnosis

What do we need to know? ICF in high HIV prevalence populations Screening algorithms Expect these to vary by HIV status Expect these to vary by effectiveness of DOTS Can ICF substantially improve TB control? ICF and treatment outcomes High and low MDR-TB settings IDU Better understanding of prevalent TB disease Impact of HIV Why is prevalent TB so common in HIV-ve pops? Does IPT increase risk of prolonged TB excretion

ICF in high HIV prevalence populations

Screening algorithms

Expect these to vary by HIV status

Expect these to vary by effectiveness of DOTS

Can ICF substantially improve TB control?

ICF and treatment outcomes

High and low MDR-TB settings

IDU

Better understanding of prevalent TB disease

Impact of HIV

Why is prevalent TB so common in HIV-ve pops?

Does IPT increase risk of prolonged TB excretion

What do we need to know? Targeted ICF: how to do it better Strategies to reach high risk populations (Tables1 & 2) High risk of TB morbidity High risk of prevalent active TB Strategies accessible by the general population ZAMSTAR TB screening clinics akin to VCT clinics TB screening clinics accessible only on referral Involving the community TB clubs / shop keepers / home based care Linked to better management of smear-negative TB

Targeted ICF: how to do it better

Strategies to reach high risk populations (Tables1 & 2)

High risk of TB morbidity

High risk of prevalent active TB

Strategies accessible by the general population

ZAMSTAR

TB screening clinics akin to VCT clinics

TB screening clinics accessible only on referral

Involving the community

TB clubs / shop keepers / home based care

Linked to better management of smear-negative TB

Institutional TB How much TB is institutionally acquired? TST conversion in student nurses 18% p.a. strict US criteria after negative 2-step in Harare Will have parallel ELISPOT data ? 10+% annual risk of TB disease if HIV+ve HIV care patients Recurrent TB disease in patients on ARVs Gold miners: recurrent TB increased from ~8% p.a to ~25% p.a. in HIV+ Coincided with introduction of HIV care clinic Can ICF control institutional TB transmission? Long term preventive therapy? Role of culture-based ICF

How much TB is institutionally acquired?

TST conversion in student nurses

18% p.a. strict US criteria after negative 2-step in Harare

Will have parallel ELISPOT data

? 10+% annual risk of TB disease if HIV+ve

HIV care patients

Recurrent TB disease in patients on ARVs

Gold miners:

recurrent TB increased from ~8% p.a to ~25% p.a. in HIV+

Coincided with introduction of HIV care clinic

Can ICF control institutional TB transmission?

Long term preventive therapy?

Role of culture-based ICF

Ongoing research Shop keepers: Malawi ZAMSTAR DETECTB Cambodia Kenya Others? Institutional TB: ARTI in student nurses Others?

Shop keepers: Malawi

ZAMSTAR

DETECTB

Cambodia

Kenya

Others?

Institutional TB: ARTI in student nurses

Others?

Recommended priority groups for targeted ICF VCT clients HIV care clinics Patients starting ARVs (IRIS) Household contacts IVDU Institutions Prisons hospitals

VCT clients

HIV care clinics

Patients starting ARVs (IRIS)

Household contacts

IVDU

Institutions

Prisons

hospitals

General population screening Insufficient evidence on which to base recommendations Potential HUGE: true TB prevention Impact of a single round or brief period of highly effective population-based ICF? DOTS can be the sustainable element (Bethel0 One passive = one ICF patient? Respective roles of reactivation and recent TB infection Effective screening tool: digital MMR?? Effective diagnostic test Effective case-management Note that in high HIV prevalence settings the ratio of prevalent to incident cases may not be all that high Would expect a rapid impact on new TB cases if prevalent TB disease control is improved

Insufficient evidence on which to base recommendations

Potential HUGE: true TB prevention

Impact of a single round or brief period of highly effective population-based ICF?

DOTS can be the sustainable element (Bethel0

One passive = one ICF patient?

Respective roles of reactivation and recent TB infection

Effective screening tool: digital MMR??

Effective diagnostic test

Effective case-management

Note that in high HIV prevalence settings the ratio of prevalent to incident cases may not be all that high

Would expect a rapid impact on new TB cases if prevalent TB disease control is improved

Conclusions ICF is natural extension of DOTS Operational research priorities & interim recommendations – p 7 Targeted linked to IPT and ARVS VCT clients Institutional TB control Household contact screening IDUs General populations: model / demonstration programmes? TB screening clinics Shop-keepers ZAMSTAR approach Household screening MMRs TB case-finding is HIV case finding Chronic cough patients in Harare HIV prevalence 83% overall: 88% in TB patients

ICF is natural extension of DOTS

Operational research priorities & interim recommendations – p 7

Targeted linked to IPT and ARVS

VCT clients

Institutional TB control

Household contact screening

IDUs

General populations: model / demonstration programmes?

TB screening clinics

Shop-keepers

ZAMSTAR approach

Household screening

MMRs

TB case-finding is HIV case finding

Chronic cough patients in Harare

HIV prevalence 83% overall: 88% in TB patients

Add a comment

Related presentations

Related pages

Tb epidemiology and other opportunistic infections in Africa

Intensified TB case-finding: still wide open to ... TB case-finding: still wide open to questions ... still wide open to questions and answers ...
Read more

Case Finding | LinkedIn

Case Finding. Articles, experts, jobs, and more: get all the professional insights you need on LinkedIn. Sign up Get more personalized results when you ...
Read more

⚡Presentation "Cost-Effectiveness of a Lateral-Flow ...

NameValueRangeReference TB Dynamics TB ... $7275 –Robust across wide range of ... still wide open to questions and answers Dr Liz ...
Read more

Open For Questions | LinkedIn

Open For Questions. Articles, experts, jobs, and more: get all the professional insights you need on LinkedIn. ... Adjunct Lecturer at Hellenic Open University
Read more

Ask Questions, Get Answers - Question.com

Answer questions Subscribe to topics Earn reward points. ... but the car still won't start? ... 92 answers | | Open. Related topics: weight, ...
Read more

Integration of Tuberculosis and HIV Services in Sub ...

Intensified TB case finding in resource ... If patients answer affirmatively to any question, they are considered to be “TB suspects ” and are ...
Read more

⚡Presentation "1 st International Treatment as ...

Presentation on theme: "1 st International Treatment as Prevention (TasP) Workshop Overview British Columbia Centre for Excellence in HIV/AIDS Julio ...
Read more