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The elimination programme should
ensure access to health care and prevention of Kala
azar for people at risk with particular attention
to the poorest and marginalized groups. The strategies will be implemented in
four hases –preparatory phase, attack phase,
consolidated phase and maintenance phase.
Major strategies
are
 Effective disease surveillance.
Early diagnosis by dipstick and complete
treatment.
Effective vector control through Integrated
Vector Management with a focus on indoor residual spray, insecticide treated
nets and environmental management.
Social mobilization of the population at risk.
Clinical and operational research to support
the elimination programme.
1. Early
Diagnosis and Complete Case Management
Effective case management of kala-azar
requires improved home care management (improved health care practices) and
increased health care seeking from trained health care personnel (including
doctors and nurses), reliable laboratory facilities and adequate supply of
medicines. Early diagnosis and complete treatment strategy would help reduce
case-fatality rates and increase the credibility of the health system, in
order to increase the utilization of health services by people suspected to
be suffering from the disease. It is proposed to use an agreed case
definition of the disease as a starting point. The case definition for
suspecting kala-azar agreed at the informal country
consultation (2003) and endorsed by the Regional Technical Advisory Group
(2004) is: history of fever of more than two weeks in a patient with no
response to antibiotics and antimalarials. This
case definition is likely to be sensitive but not specific. Additional signs
that are useful include weight loss and enlarged liver and spleen. However,
these are not likely to be recognized by health workers and health
volunteers. Patients with the above-mentioned symptoms should be screened by
‘rk 39’ or DAT and, if positive, treated with an
effective drug. Confirmation of kala-azar can be
done by examination of bone marrow aspiration but this is difficult and
invasive. Therefore it can be done only in some hospitals (district hospitals
in Bangladesh and India and zonal hospitals in Nepal). The
effective and reasonably safe oral drug recommended is miltefosine. This drug has been registered in India. It
cannot be used in pregnancy and in women of reproductive age who are not
using contraceptives regularly. If possible, miltefosine
should be administered as directly observed treatment in order to achieve
total compliance, retain its efficacy and delay the appearance of drug
resistance. Use of treatment cards is likely to contribute to better
compliance. Paromomycin, an injectable
drug, is promising and is undergoing phase III trials. Amphotericin
B and liposomes are rescue drugs in the treatment
of kala-azar.
2. Integrated
Vector Management and Vector Surveillance
The mainstay of vector control is indoor residual
spraying. While DDT can be used for the control of kala-azar
in India suitable
alternatives have to be selected for Bangladesh
and Nepal
since DDT is not available or is not recommended as a national policy. Pyrethroids can be considered though these are very
expensive and rapid development of resistance is a constraint. Adoption of a
uniform insecticide strategy is advisable through intercountry
cooperation. Through geographical information system (GIS) and remote sensing
(RS), water bodies should be identified in the district selected and spraying
operations carried out within a radius of one kilometer of these water
bodies. Mapping of the district for water bodies would be useful in limiting
spraying operations to those areas where maximum impact is likely to occur.
This will help economise on insecticide consumption
and help control environmental degradation. Selective IRS would be advisable
only when surveillance is geared up and geographic mapping with validation is
available; until then, IRS based on incidence reporting may be continued.
Spraying operations should be undertaken at the most appropriate time of the
year. IRS should achieve maximum coverage and be done thoroughly in order to
have a lasting impact. Community mobilization is required to get maximum
cooperation from households so that IRS helps in eliminating the vector
effectively. IRS should be followed by entomological work to provide evidence
on the efficacy of IRS. This strategy would help contain costs and also
ensure good quality of IRS operation in order to produce the desired impact.
Another strategy that will complement IRS is reducing human vector contact
through ITNs. Strategies for ITNs
should be developed and the distribution monitored for impact. Sanitation in
the household, peridomestic environment and the
community plays an important role in eliminating vector breeding and reducing
longevity with consequent reduced risk of transmission. The success of ITNs and environmental sanitation would depend on
effective behavioural change communication (BCC).
Therefore a BCC strategy that includes ITNs and
environmental management is to be considered as part of IVM. This should be
sustainable.
Surveillance of P. argentipes
vector is important to determine the distribution, population density, major
habitats, and spatial and temporal risk factors related to kala-azar transmission. It would be important to monitor
the levels of insecticide resistance. The information on vector surveillance
would be crucial for planning and programming IVM strategy, Integrated
disease (including PKDL) and vector surveillance is recommend for kala-azar elimination.
3. Effective
Disease Surveillance through Passive and Active Case Detection and Vector
Surveillance
Cases of kala-azar for
surveillance should be classified into: (a) suspect; (b) clinical and (c)
confirmed cases. Adoption of this approach will help in the use of uniform
criteria. Surveillance includes reporting of cases of PKDL since these are
responsible for continued transmission of the disease.
Currently, surveillance through passive case detection is
done in government institutions. This does not give a true picture since (a)
a majority of cases of kala-azar go to private
doctors including quacks and there is no reporting from these health care
providers; (b) treatment is often started without a definitive diagnosis of kala-azar, and (c) many cases do not seek health care at
all because of poverty and socio-cultural constraints. Despite the above
constraints, passive case detection and reporting is used to monitor the
trends of the disease. The strategy will be to strengthen reporting through
improved diagnosis and treatment and to establish partnership with private
health care providers including private doctors and to ensure that community
is empowered with knowledge of risks of seeking services of quacks for
diagnosis and treatment, as an effort to make appropriate treatment available
to the community through qualified professionals. For improved surveillance, kala-azar should be made a notifiable
disease in the affected areas. Disease surveillance for kala-azar
should comprise monthly reporting and feedback at district level, and
evolving a system of regular reporting mechanism with state and national
authorities. Reporting to WHO should
be done on an annual basis (if possible twice a year) and endemic countries
should send reports on an agreed reporting format.
As the programme improves and
capacity is increased, passive case detection (PCD) should be supplemented
with active case detection (ACD) that is supported by laboratory diagnosis.
While active case detection is recommended at least once a year in the
beginning (if possible two times per year), active case detection will become
more important as the number of cases reported by passive case detection
declines. Active case detection should also be supplemented by laboratory
confirmation of suspected cases.
4. Social
Mobilization and Building Partnerships
Behavioural change interventions
are important in the elimination of kala-azar and
for the success of early diagnosis and treatment adherence. Effective BCC can
also help in promoting early care seeking. Participation of community and
families in indoor residual spraying and in reducing human vector contact is
necessary. Social mobilization should be an integral part of the elimination programme right from inception. National programmes should plan adequate resources for effective
BCC.
Partnerships will be necessary at all levels i.e. at
district and state levels, at national level and with international
stakeholders. Some of the elimination and eradication programmes
(polio, leprosy, lymphatic filariasis) owe their
success to multi-partner leadership.
Partnerships networking and collaboration will be required
with other programmes like vector-borne disease programmes (malaria, dengue, filaria) and others, e.g. HIV/AIDS, TB, and
leprosy. Anaemia control, improvement in
nutritional status and poverty alleviation programmes
should be made partners of kala-azar elimination programme.
5. Clinical
and Operational Research
Diagnostic and therapeutic tools are available for elimination
of kala-azar. More clinical research is required to
enable the addition of new drugs and diagnostics. The available diagnostic
tests should be validated under field conditions. Additional research is
needed to identify and evaluate techniques for rapid assessment and mapping
of the disease, to develop a mechanism for monitoring the effectiveness of
intervention strategies. Operational research is recommended to establish
monitoring of drug resistance, drug efficacy and quality of drugs used in the
programme. Research is also needed to optimize the
effectiveness of drugs including the use of combination drugs in the
treatment of kala-azar. Research is also needed in
searching for cases of PKDL and for satisfactory treatment of cases of PKDL.
This is at present a serious constraint in the elimination of kala-azar. Implementation research is required in pilot
districts where the programme should be monitored
closely to identify constraints and lessons learnt. Research on increasing
access of interventions to the poorest people and for operationalizing
IVM is recommended. An important operational research issue is to evaluate
the public-private mix. Networking is an important strategy to optimize
operational research and link it with programme
implementation.
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