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AFRO-NETS> Tuberculosis articles
Tuberculosis articles
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I am attaching the abstracts of two articles and an editorial about
tuberculosis. I feel that these are important articles that need to
be reviewed by anyone involved in health in Africa or in TB control.
I have copied the abstracts from the HealthNet Newsletter.
Richard Laing
Dept. of International Health,
Boston University School of Public Health
mailto:[email protected]
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1.0 INFECTIOUS DISEASES / TUBERCULOSIS
1.1 From their own perspective. A Kenyan community's perception of
tuberculosis
AU R Liefooghe, JB Baliddawa, EM Kipruto, C Vermeire and AO De
Munynck.
IN Department of Clinical Sciences, Unit of Epidemiology, Institute
of Tropical Medicine, Antwerpen, Belgium; Faculty of Health
Sciences, Moi University, Eldoret, Kenya; School for Social,
Cultural and Development Studies, Moi University, Eldoret,
Kenya.
SO Trop Med and Int'l Health 1997;2:809-21.
SUMMARY
Early passive case finding and Treatment compliance are the corner-
stones of tuberculosis (TB) control programs. As human behaviour
plays a critical role in both strategies, a better understanding of
it is important for the planning and implementation of a successful
TB program, especially for the health education component. Our quali-
tative study in Uasin Gishu, Denya, aimed at better understanding of
the community's beliefs and perceptions of TB, recognition of early
symptoms and health-seeking behaviour. Five focus groups with a total
of 49 people were held: one with hospitalized TB patients, two with
rural and two with urban participants.
Tuberculosis is well known in the communities and many vernacular
names for the disease exist. TB is perceived as a contagious, 'sensi-
tive' disease difficult to diagnose and treat. Community members be-
lieve that TB should be diagnosed and treated in a hospital or by a
medical doctor and not at the peripheric level. TB treatment is per-
ceived as long, agonizing and cumbersome. Traditional treatment is
considered a valid alternative to modern treatment, believed to be as
effective and much shorter. Initial symptoms such as cough and fever
are often overlooked and/or confused with malaria or a common cold.
Symptoms associated with the disease refer to the later stage of TB.
TB is attributed to causes such as smoking, alcohol, hard work, expo-
sure to cold and sharing with TB patients. Many participants believe
TB is hereditary. Prolonged self treatment and consultation with the
traditional health sector as well as the social stigma attached to
the disease increase patient's delay. Only after symptoms persist for
some time and/or the suspect's health deteriorates, are modern health
services consulted. These social conditions necessitate culturally
sensitive health education, taking into account local perceptions of
TB.
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1.2 Coping with Africa's increasing tuberculosis burden: are commu-
nity supervisors an essential component of the DOT strategy?
AU D Wilkenson, GR Davies
IN Centre for Epidemiological Research in Southern Africa, South
African Medical Research Council, Hlabisa, South Africa; Hlabisa
Hospital, Hlabisa, South Africa; Division of Tropical Medicine,
Liverpool School of Tropical Medicine, UK.
SO Trop Med and Int'l Health 1997;2:700-704.
SUMMARY
Tuberculosis incidence in Africa is increasing dramatically and frag-
ile health systems are struggling to cope. Potential coping capacity
may be within affected communities but this capacity needs to be har-
nessed if tuberculosis is to be controlled. Since 1991 all patients
with tuberculosis in Hlabisa health district, South Africa have been
eligible for community-bases directly observed therapy (DOT). Pa-
tients are supervised either by a health worker (HW) in a village
clinic, or in the community by a community health worker (CHW) or a
volunteer lay person (VLP). Tuberculosis incidence increased from 312
cases in 1991 to 1250 cases in 1996. By December 1995, 2622 (87%) of
3006 patients had received DOT, supervised mainly by VLP (56%) but
also by HW (28%) and CHW (16%).
The proportion supervised by HW fell form 46% in 1991 to 26% in 1995
(P<0.0001). More patients supervised by VLP (85%) and CHW (88%) than
by HW (79%, P=0.0008) completed treatment. Case holding by HW de-
clined more between 1991 and 1995 (84% to 71%, P=0.02) than did case-
holding by both CHW (95% to 90%, P=0.7) and VLP (88% to 84%, P=0.4).
Mortality was similar (4-6%) and stable over time, irrespective of
the supervisor. High tuberculosis treatment completion rates are
achievable and sustainable for several years n resource-poor settings
despite a massively increased case load if community resources are
harnessed. Patients may be more effectively supervised by voluntary
lay people than by health workers under these circumstances, without
being placed at increased risk. These findings suggest that community
supervisors may be an essential component of any DOT strategy.
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1.3 Editorial: Tuberculosis control: did the program fail or did we
fail the program?
AU B Dujardin, G Kegels, A Buve and P Mercenier.
IN N/A.
SO Trop Med and Int'l Health 1997;2:715-8.
INTRODUCTION
Under pressure of the increasing numbers of tuberculosis (TB) cases
in the world, TB control has once again become a major challenge. As
such it is the subject of intensive scientific activity, as evidenced
by the numerous studies and publications that have been devoted to it
over the last few years. The Lancet recently published tow documents
which summarize present concerns: the minutes of the conference or-
ganized in Washington DC by The Lancet, in September 1995: "the chal-
lenge of tuberculosis: statements on global control and prevention"
and an article which proposes substantial modifications of activities
in the standard tuberculosis control program.
>From the most recent literature, two major challenges may be identi-
fied: On the one hand there is a call for the development of new di-
agnostic techniques, especially procedures that are faster and more
sensitive than smears or cultures and techniques that would improve
or facilitate the diagnosis of smear-negative TB; and a call for new
treatments that are effective against multidrug-resistant TB and/or
that would shorten length of treatment. On the other hand, the scien-
tific community also acknowledges the importance of some operational
aspects of TB, such as problems of drugs delivery and financing, and
patient compliance to treatment. This last point is considered a top
priority, and WHO is currently promoting a DOT (Daily Observed Ther-
apy) as a new strategy to be implemented by each TB control program.
However, other aspects linked to the organization and the functioning
of health services, or linked to the perception of the illness by
both health personnel and patients, are underestimated. In his presi-
dential address, given at the 21st Andhra Pradesh TB and Chest Dis-
eases Conference held in July 1994 in India, Dr. Ranga Tao proposed a
critical self-evaluation of the state TB control program which
started more than three decades ago. This physician, who has been
working as a TB officer for more than 25 years, identified 17 major
weaknesses of the TB control program. His very impressive list begins
with:
"We failed in implementing the program in the health districts.
We failed in providing the services of all the trained medical and
paramedical key personnel continuously in some districts, due to fre-
quent transfers or otherwise.
We failed improving the laboratory services in the primary health
centers.
We failed in seeking administrative support of the competent authori-
ties to run the program...etc."
What is striking about this presidential address given by a TB spe-
cialist to the members of a tuberculosis association, is that most of
the 17 weaknesses identified are related to human or organizational
failures and some to lack of political will, but none are directly
attributed to technical problem.
Whether in industrialized or in low-resource countries, our experi-
ence points in the same direction: we failed in implementing TB con-
trol programs mainly for operational reasons (human and/or organiza-
tional failures linked to the overall functioning of health systems),
not because of a problem of diagnostic tools or drug resistance.
These operational reasons are due to specific challenges arising from
the integration of a TB control program into general health services
and form the quality of the overall functioning of the health serv-
ices.
AN OPERATIONAL MODEL FOR THE ANALYSIS OF TB CONTROL PROGRAMS
Piot, who at that time was attached to WHO's TB program, put forward
a model enabling a comprehensive assessment of all the different
technical and operational aspects of a TB control program. We propose
a simplified version of this model focusing on the problems raised by
the integration of the TB program into the general health services.
The model, which is conceptually simple, is based on the passive de-
tection strategy of smear-positive TB cases. It starts form a de-
scription of the different steps individuals in the community go
through between becoming ill with active TB and getting cured by the
TB control program under consideration. The main steps - the number
of which may vary according to the characteristics of the control
program - are summarized below:
Step 1: Motivation: Patients suffering form symptoms related to TB
contact a health care delivery point.
Step 2: Selection: The health professional suspects TB and requests a
sputum examination (smear).
Step 3: Examination: The sputum test is correctly carried out o the
patients thus selected.
Step 4: Sensitivity: The smear is positive if the patient has bacilli
in the sputum.
Step 5: Prescription: The newly identified case of TB receives the
correct treatment prescription.
Step 6: Treatment: The TB patient obtains the prescribed treatment.
Step 7: Regularity: The TB patient takes his treatment regularly as
prescribed.
Step 8: Effectiveness: The patient is cured with a certain probabil-
ity if treatment is taken as prescribed.
In ideal circumstances, all new cases of TB consult without delay,
are suspected of suffering of TB and are diagnosed promptly and accu-
rately, receive a correct treatment prescription, obtain the pre-
scribed treatment and take the full treatment regimen regularly to
finally be cured. This would lead to a 100% prompt cure rate of new
TB cases in the population and to decrease in the transmission of TB.
Of course, real life is different.
At each step problems and difficulties arise: a suspect individual is
not identified, there is no reagent to carry out the sputum smear, a
positive sputum is missed by the laboratory technician, drugs are out
of stock, the patient does not present at the health center regu-
larly, and son on... The probability that a patient does proceed from
one step to the next is a measure of the performance of different TB
control activities.
Some steps are essentially technical (sensitivity of diagnostic test,
theoretical effectiveness of treatment) and depend on the choice made
at the central level by the TB program officers. Their probabilities
are theoretically independent of circumstances. Other steps' prob-
abilities are quite variable form one situation to another because
they depend in the first place on the quality and performance of the
health services where TB control activities are integrated. These so-
called "operational steps" depend on the operational quality of the
health services such as they are and include: motivation, selection,
examination, prescription, treatment and regularity. To illustrate
the importance of the problems encountered in the field and the need
of a global approach, we briefly discuss tow of these operational
steps, examination and regularity.
Examination is often the weakest link in the chain of steps that
should lead to the cure of TB patients. Many types of problems are
encountered in practice. First there is the case of the doctor who
failed to properly explain the importance of this examination, and
the patient who thus is not inclined to queue up again at the labora-
tory, especially if he needs to come back two more times in order to
complete the required series of three sputum examinations and one
more time to hear the result (the whole process often takes more than
a week, several days at best. Secondly, the laboratory technician
does not adequately instruct the patient on how to produce sputum or
does not allow him the necessary time, the collected specimen is sa-
liva instead of bronchial secretions. We have seen this situation
over and over again. Thirdly, the sputum collection may be correct,
but the smear not correctly prepared, old slides are used (one of the
sources of false positives), the sputum is badly spread out, reagents
are either past the expiry date or out of stock, procedure is not
followed, the staining is done badly.
Lastly, an adequate sputum sample is correctly prepared, but micro-
scopic examination by the laboratory technician is not reliable due
to incompetence or lack of professional attitude. Another explanation
- our own experience in Latin America - has to do with integration of
TB programs. In their willingness to detect as soon as possible al
new TB cases, TB officers tend to push health professionals to iden-
tify more and more suspect patients (the sometimes observed "rule"
that 1% of the new patients at the OPD or curative clinic have to be
selected for sputum examination). As a consequence, too many 'sus-
pects' may be referred to the laboratory, the workload becomes too
high, the health officer tends to select fewer suspected patients
and/or the laboratory technician does not respect the prescribed du-
ration of reading the slide and the result is a false negative. This
is an example where maximization could be counterproductive.
The reliability of this step (quality of sputum production and col-
lection, quality of smear preparation, quality of microscopic exami-
nation) thus appears to be crucial, all the more so since it depends
entirely on factors within the health services, and especially since
high quality 9in other words, a probability value close to 1.0) is
technically and organizationally feasible. As a matter of fact, op-
erational research has shown that decentralization of this step and
the reading of slides by auxiliary personnel with only 6 weeks'
training and even less (2 weeks in one author's field experience -
PM), could be done without any noticeable loss of quality, but re-
quires regular supervision. None of these problems are identified or
discussed in recent literature. Knowing the present state of dilapi-
dation of many health services, regular surveillance of the technical
quality of this step is absolutely necessary in order to avoid too
many false positives as well as false negatives.
Regularity or long-term compliance among TB patients under treatment
varies from one program to another. As for Step 1, Motivation, this
is highly influenced by geographical accessibility, indirect costs,
quality of relationship between health professionals and patients,
state of health of the patient, defaulter retrieval procedures imple-
mented by the health services, capacity of the service to solve so-
cial problems, family problems and various other kinds of problems
that patients encounter. What is certain is that ensuring a TB pa-
tient's treatment regularity is difficult. In fact, we know very lit-
tle in this field; we do know many of the factors that are associated
with irregularity, but very little research has been done t evaluate
interventions with a view to improve regularity. For certain authors,
admission of patients in the hospital would guarantee better regular-
ity, whereas it has been demonstrated that in a functional health
district the health centers can ensure better regularity than can be
obtained by admission in the hospital. In Korea, experimental re-
search showed a significant increase of patients' regularity form 65%
to 79% when central level supervision was organized in order to help
district health professionals to solve their operational problems.
Direct Observed Therapy (DOT) is very fashionable at the moment and
sometimes presented as a panacea. This strategy guarantees of course
a high level of regularity, but also has a number of disadvantages.
It is costly in terms of human resources and difficult to implement
in sparsely populated regions. The DOT strategy also presents another
major problem: the underlying assumptions that the patient is incapa-
ble of understanding the importance of what he or she is being asked
to do: regular treatment for a sufficiently long time. However, our
experience does not support this; if health professionals take the
necessary time to explain clearly what is at stake, and if they are
able to ensure an empathic follow-up of the patient, the majority of
TB patients can be regular.
CONCLUSION
The use of an operational model like the one we have proposed allows
us to identify the problems that may arise at different steps and can
be used as a tool for dialogue between specialists in charge of TB
control and public health professionals. This model also allows us to
improve the identification of research priorities, especially in the
field of operations research.
Of course, technical research on diagnostic tools (to decrease the
dependency on qualitative factors such as staining reading) and on
treatment (to decrease the dependency on regularity) may help control
some of the operational difficulties. However, new techniques will
more often simply displace the problem: if a one-day TB treatment
will solve the compliance failure, this operational problem still re-
mains a challenge with the present 'short course' therapy.
To be effective, tuberculosis control needs to be conceived in a com-
prehensive way, be it before or in the HIV era. The different steps
of a TB program are closely linked, and concentrating all resources
on one step, while neglecting the others, will not lead to percepti-
ble improvement. We will neither reduce human suffering nor decrease
TB transmission by curing a few patients more with a novel treatment
that is even better than the existing ones if, at the same time, the
majority of new patients are not identified in a timely way. By the
same token, the transmission of TB will not be reduced if we concen-
trate all resources on the DOT strategy while failing to ensure cor-
rect selection and examination of suspect cases, leading to false
negatives who continue to contaminate their environment.
There are no miracle solutions in TB control. We feel that present
approaches and research priorities are too narrowly focus don techni-
cal aspects while ignoring those that have to do with the overall
functioning of health services and integrating the TB program into
the general health services. Furthermore, problems related to the
perception of TB by both health personnel and patients are underesti-
mated. The different elements of an entire program need to be im-
proved together. An operational model like the one we propose will
help us to reach this comprehensive approach.
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