MALARIA ELIMINATION IN ZANZIBAR - Soper Strategies

MONITORING & EVALUATION (M&E)
As discussed in Chapter 2, current and planned methods for
M&E would not be sufficient if Zanzibar were to embark on
elimination, including due to inadequate sample sizes and
inappropriate parasite detection methods. An additional
serological prevalence survey, conducted bi-annually, is thus
recommended with a sample size large enough to detect very
low levels of parasite density. Based on the costs of typical
malaria indicator surveys with a sample size of roughly 8,000
and assuming that this sample size would need to at least double
and that serological testing would be added at roughly $2 per
slide, we estimate that these surveys would add $100,000 per
year for M&E of an elimination program. In addition to these
surveys, an elimination program will need to implement a
range of other core M&E activities. It is assumed that these will
represent a similar proportion of the overall budget as M&E does
for sustained control in the latest Global Fund proposal (8%). 2
As the surveys and other M&E activities will be consistently
implemented throughout the program, we do not expect that
this cost will decline over time.
TOTAL COST IMPLICATIONS OF ELIMINATION
Figure 29 shows a comparison of the annual difference (%) in
expenditure for two elimination scenarios compared to sustained
control, over the course of the 25 year period analyzed. This figure
presents a clear answer to the core question asked in this chapter:
elimination will not be cost-saving in the short- or mediumterm
in Zanzibar. The additional investment needed to move
towards elimination initially results in an almost 85% increase
in average annual expenditure compared with sustained control,
with costs remaining 45-50% more expensive over the course
of the remainder of the effort to reach elimination. Contrary to
expectation, costs do not dramatically decline once elimination is
achieved and the country enters the prevention of reintroduction
phases: in the most likely scenario, costs in this phase are 5%
higher than during the elimination period. This is because as
long as importation risk remains at current or modestly reduced
levels, interventions will need to remain constant in order to
prevent rapid resurgence.
For the purposes of comparison, the best possible elimination
scenario is included in this costing although the authors believe
it is unlikely the necessary reduction in importation risk will be
possible. Under this scenario in which LLINs are withdrawn
entirely, annual costs during the prevention of reintroduction
phase will decrease substantially. The degree of this reduction
depends on the assumed implementation of border screening:
if comprehensive screening is introduced in order to reduce
importation risk to the necessary level, ongoing costs will be
roughly equivalent to (4% higher than) sustained control, while
if screening is less extensive or not conducted at all annual costs
could fall as low as 20% below sustained control.
2 This ratio is also in line with the requirement of most donors that 5-10% of
total program budgets be spent on M&E.
3 | Financial Feasibility
FIGURE 29: ESTIMATED ANNUAL PERCENT DIFFERENCE IN EXPENDITURE
BETWEEN ELIMINATION SCENARIOS AND SUSTAINED CONTROL
100%
80%
60%
40%
20%
0%
-20%
-40%
SCENARIO 1: NETS > 75% EFFECTIVE COVERAGE, IMPORTATION RISK
REDUCES FROM 2 TO 1/1000 INHABITANTS PER YEAR
SCENARIO 2A: NO NETS AFTER 2030, IMPORTATION RISK REDUCES FROM
2 TO 0.4/1000 INHABITANTS PER YEAR (INCLUDES BORDER SCREENING)
SCENARIO 2B: WITHOUT BORDER SCREENING
SUSTAINED CONTROL
2011
2013
2015
2017
2019
2021
2023
As shown in Figures 30 and 31, the higher costs of both elimination
and prevention of reintroduction are driven primarily by
increased surveillance and diagnosis. This is particularly evident
in the second elimination scenario where these activities combined
comprise 47% and 65% of total costs in the elimination
and prevention of reintroduction phases respectively compared
to just 15% for sustained control. In the more likely scenario
where universal LLIN coverage needs to be maintained, case
management and surveillance represent 45% and 35% for the
elimination and prevention of reintroduction phases respectively,
which is in line with experiences from other countries.
For example, Mauritius continues to spend $2.15 per capita to
prevent the reintroduction of malaria, 39% of which is devoted
to surveillance activities (Tatarsky, unpublished data). The
estimated average per capita costs of prevention of reintroduction
on Zanzibar varies between $1.73 and $2.27 depending
on the elimination scenario, aligning closely with the benchmark
provided by the Mauritius case. One of the only other
available benchmarks is the report of the Eighth WHO Expert
Committee on Malaria, which estimated in 1961 that the cost
of prevention of reintroduction was roughly 65-75% of the
“attack” (elimination) phase (WHO, 1961). Given that Zanzibar
is facing higher transmission and importation risk than most of
the countries considered at that time, the second elimination
scenario, with the prevention of reintroduction phase between
69% and 88% of the elimination phase, appears to be largely in
line with this benchmark.
2025
2027
2029
2031
2033
73