Treatment and Prevention of Tuberculosis Among Refugees and IDPs
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Transcript Treatment and Prevention of Tuberculosis Among Refugees and IDPs
Treatment and Prevention of
Tuberculosis Among Refugees and
IDPs
Rafik Hanna, M.D.
St. Luke’s Roosevelt
Global Health Lecture
Statistics on TB
• 1/3 of the world’s population infected with TB (latent),
with a lifetime risk of developing active TB of about 10%.
• In 2010, approximately 8.8 million incident cases of TB.
• Incidence of TB (absolute number) has been falling since
2006.
• 1.2-1.7 million deaths annually.
• Of TB patients tested for HIV in the Africa region in 2010,
44% had HIV co-infection.
• About 80% of all TB patients live in sub-Sahara Africa
and Asia, where the majority of refugees and IDPs
currently live.
• In 2009, there was an estimated 9.7 million orphan
children as a result of parental TB deaths.
• India and China account for 40% of new cases of TB in
2010 (burden decreasing in both countries).
• 11,182 reported cases of TB in the U.S. in 2010.
Incidence of TB 2010
Prevalence of HIV in New TB
Cases 2010
TB Incidence Rates 1990-2010 in
High-Burden Countries
TB Prevalence Trends and
Forecast
Basic Facts on Course of TB
• In the natural course of the disease,
among sputum smear (+), HIV (-) cases,
70% die within 10 years.
• In patients who are culture (+), sputum
smear (-), HIV (-), 20% die within 10 years.
• Cure rates are approximately 90% for
patients treated with anti-TB drugs.
MDR-TB Case Prevalence
Regional Trends in MDR-TB
Stop TB Strategy
Components of the Stop TB
Strategy
• Pursue high-quality DOTs expansion and
enhancement.
• Address TB/HIV, MDR-TB, and the needs of the
poor and vulnerable populations
• Contribute to health system strengthening based
on primary health care.
• Engage all care providers.
• Empower people with TB, and communities
through partnership.
• Enable and promote research.
Definition of TB Cases
*XDR TB is MDR TB resistant to any FQ and one of three injectable
aminoglycosides (capreomycin, kanamycin, and amikacin).
Xpert-MTB/RIF
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New test for rapid diagnosis of TB.
Cartridge-based nucleic acid amplification assay.
Endorsed by the WHO in 12/2010.
Developed by Cepheid, Inc., with UMDNJ (Newark), FIND; support –
NIH, BMGF.
Detects Mtb and mutations conferring rifampicin resistance from
sputum samples.
Sputum sample results in 100 minutes.
Sensitivity: 1 sputum (98%) for smear (+) pulmonary TB; 1 sputum
(72.5%), 2 sputums (85.1%), 3 sputums (90.2%) for smear (-)
pulmonary TB. Specificity: 99.2%.
Lab services, microscopy, and culture still needed to monitor
treatment progress and to detect resistance to drugs other than
rifampicin.
Constraints of Refugee and IDP
Situations
• Marginalization of refugees and IDPs,
sometimes with more attention needed to the
more vulnerable groups.
• Malnutrition and other acute infectious diseases.
• Breakdown of normal systems of screening and
universal precautions.
• Social, political, and cultural disruption.
• Difficulties for planning longterm programs.
• Refugees and IDPs held in suspicion as being
agents of epidemic introduction.
Characteristics of TB
• TB continues to be a disease of poverty.
• Poor living conditions, poor hygiene, overcrowding,
inadequate ventilation, and malnutrition favor the spread
of the disease.
• Other risk factors include HIV, DM, ESRD, Vitamin D
deficiency, smoking, silicosis, alcoholism, adult males,
malignancy, steroid therapy, anti-TNF medications,
genetic variants.
• Though much has been learned about TB transmission,
much still remains to be unknown regarding the
transmission pathway.
• Vaccine-efficacy is very limited at this time (BCG efficacy
in young children to prevent miliary TB and tuberculous
meningitis).
Characteristics of TB
• Among refugees, there is often the additional loss of
community structure and regular access to health care.
• Many of these aforementioned factors thereby make
refugee and IDP situations possible ideal grounds for the
spread of TB.
• In the 1990s in Kenya, the incidence of new patients with
infectious TB in refugee camps was four times the
incidence of the local population. This placed an extra
burden on the Kenyan TB program.
• Additionally approximately 200 million people live in
countries affected by complex emergencies (a
humanitarian crisis in a country, region or society where
there is total or considerable breakdown of authority
resulting from internal or external conflict and which
requires an international response that goes beyond the
mandate or capacity of any single agency and/or the
ongoing United Nations country program).
Dilemma of TB Treatment in
Refugee Situations
• Transience of the population with unforeseen mobility.
• Short-term mandates of most relief agencies, resulting in
insufficient commitment in terms of time and resources.
• Security problems leading to poor compliance and
withdrawal of health agencies.
• Limited financial resources in post-emergency phases.
• Desiring to provide no better health care for refugees
than those available to local citizens.
• Ineffective programs may do more harm than good (keep
infectious patients alive for a small amount longer,
remaining as sources of spread, yet still dying from the
disease; creating MDR TB)
TB Program
• Not to be implemented in the acute emergency phase
(death rates are <1 per 10,000 population per day).
• Data from the refugee or displaced population indicate
that TB is an important health problem.
• Basic water, nutrition, shelter, and sanitation needs are
being met.
• Essential clinical services and basic drugs for common
illnesses are available, with these services being
accessible to a large part of the population.
• Objective is detect at least 70% of TB cases existing in
the population and to cure at least 85% of them.
TB Program Key Elements
• Political commitment to TB control with
sustained financing.
• Case detection through quality-assured
bacteriology (recent approval for Xpert-MTB/RIF
use may play a role).
• Standardized treatment with supervision and
patient support.
• Effective drug supply and management system.
• Monitoring and evaluation system and impact
measurement.
Steps in TB Program
Implementation in Refugee/IDP
Settings
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Assess the burden of TB among the population.
Determine whether the initiation criteria have been met.
Raise awareness among host and refugee populations
Become aware of the national treatment (NTP) regimens
being used. Explore links with the local health system,
at least to use facilities such as x-rays.
• Secure funding to admit patients into the program for a
12-month period and for a total commitment of 18
months.
• Determine staffing requirements, patient accomodations,
existing lab resources, recording system, and methods
for monitoring and evaluation.
Training Staff for a Successful TB
Program
• Staff must have basic knowledge of TB.
• NTP, WHO, NGOs may be a source of such trainers.
Also consider possible experienced staff among
refugees/IDPs.
• Primary healthcare workers must be aware of 1st signs of
the disease and the process of diagnosis.
• Lab staff must be familiar with quality control and record
management.
• Records must include registering all TB suspects, TB lab
patient registry, individual patient records, and all those
treated.
• Repeat smears at 2, 5, and 6-8 months of treatment.
Key Steps of TB Program Impementation
Diagnosis of TB in Adults
• The most important symptom in the identification
of TB in adults is cough of duration longer than 2
weeks.
• Must identify smear-positive pulmonary TB
cases since they are main source of infection in
the community.
• Patients should provide 3 sputum samples in 2
days and treat if positive.
• If the initial 3 smears are negative but pulmonary
TB is still suspected, give amoxicillin or cotrimoxazole for at least one week and reexamine 3 new samples if symptoms persist.
Criteria for Diagnosis of Pulmonary
TB in Adults
WHO Recommendations for Diagnosis of
TB in HIV-prevalent and Limited Resources
Treatment Regimens of TB
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Based on standard combinations of five essential TB
drugs: rifampicin, isoniazid, pyrazinamide, ethambutol,
and streptomycin.
Each regimen consists of two phases:
1.
2.
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An initial (intensive) phase: This phase lasts 2–3 months during
which 3–5 drugs are given daily under direct observation to
reduce the number of TB organisms to very low levels.
A continuation phase: This phase lasts 4–6 months during
which 2–3 drugs are given 3 times a week under direct
observation or, in some cases (e.g. during repatriation of
refugees), 2 drugs are given daily for 6 months unsupervised, in a
fixed-dose combination form.
Actually swallowing every dose of rifampicin-containing
treatment must be directly observed by a health
worker, or a trained community member.
Fixed-dose Drug Combinations
Treatment Categories of TB
Recommended Drug Dosages
Dosing Schedules of New Cases
using fixed-dose combination drugs
Definition of Outcomes
Special Considerations
• Pregnant women may be treated with the same
regimen as others, except for streptomycin
because of toxicity to the fetus.
• Women breastfeeding should receive a full
course of TB treatment. All TB drugs are safe in
breastfeeding. The infant of a smear-positive
mother should receive INH.
• OCPs are likely to be ineffective while taking
rifampicin.
TB in Children
• The greatest likelihood of children developing TB
disease after infection occurs within 1 year and
most comonly in infants and children under 5
years of age.
• The most common type of TB in children is
extrapulmonary TB.
• Pulmonary TB Diagnosis: contact with smearpositive pulmonary TB case; respiratory
symptoms >2 weeks not responding to
antibiotics; weight loss; positive TST.
• If a close contact active TB case occurs, children
under 5 should be treated with 6 months of INH.
TB Treatment in Children
Repatriation
• Stop recruitment of new patients.
• Coordination between the two programs and the
NTPs of the two countries.
• Set up administrative systems for transfer of
patient cards and notes (patients should have
personal cards with them).
• Harmonize treatment protocols.
• Supply of drugs for transfer process.
• Pick up at border for close follow up in the
country of return.
Bibliography
• http://www.cdc.gov/tb/statistics/
• WHO Global Tuberculosis Control 2011
• WHO Tuberculosis Care and Control in Refugee and
Displaced Populations 2nd edition 2007
• http://www.who.int/bulletin/volumes/85/8/06037630/en/index.html
• Lawn SD, Zumla AI. Tuberculosis. Lancet. 2011 Jul
2;378(9785):57-72
• http://www.jhsph.edu/bin/k/c/Pages_from_Chapter_7_.pd
f.
• Germaine Hanquet. MSF. Refugee Health: An
Approach to Emergency Situations. Malaysia:
Macmillan, 1997.