Summary box
In sub-Saharan Africa (SSA), the COVID-19 pandemic could cause major disruptions to
the delivery of malaria vector control interventions.
Such disruptions could potentially lead to significant increases in malaria morbidity
and mortality in the region.
The challenges for sustaining malaria vector control are multiple, from funding shortages
to obstacles during implementation.
The latter are more difficult to appreciate and are described from experience in the
field.
There is a need for major commitment from governments, organisations and individuals
to avert a malaria public health disaster in SSA.
The COVID-19 pandemic can potentially bring public health interventions in low-income
countries to a collapse. In sub-Saharan Africa (SSA), the saturation of health systems
can expose pre-existing fragilities and exacerbate the myriad health problems afflicting
human populations. In particular, SSA bears the brunt of malaria,1 which caused around
200 million cases and 400 000 deaths in 2018, mostly in young children.2
The challenges for health systems of coping with COVID-19 and malaria at the same
time are onerous due to complex interactions between both diseases. Malaria and COVID-19
can be symptomatically similar, complicating differential diagnosis. Therefore, malaria
infections may go undiagnosed in people presenting fever and testing positive for
COVID-19, potentially causing malaria cases to go untreated. In another scenario,
symptomatic, malaria-infected individuals could be deterred from seeking healthcare
due to fear of COVID-19 infection or could be denied treatment if health centres and
hospitals were overwhelmed. Perhaps most importantly, the increasing demand for resources
to curb COVID-19 and the curtailment of economic activities driven by the pandemic
could lead to substantial reductions in government revenues,3 undermining their ability
to finance essential social services, including life-saving malaria vector control
interventions. Here, we focus our discussion on vector control for preventing malaria
in SSA in the context of the current pandemic, neither neglecting the importance of
other essential malaria health services and interventions nor the importance of malaria
in other endemic areas.
The scaling-up of vector control, chiefly insecticide-treated nets (ITN) and indoor
residual spraying (IRS), was the main driver for the significant reductions of malaria
burden in SSA in the past two decades.4 Vector control is normally targeted to the
populations at the highest risk of malaria transmission. IRS should be delivered annually
before the beginning of the transmission seasons.5 ITN, on the other hand, should
be distributed through triennial mass campaigns and maintained over time through continuous
distribution channels such as schools and antenatal clinics.6
During the pandemic, these interventions may be hindered by reallocation of limited
resources to COVID-19 response and disruptions in supply chains of IRS insecticides
and ITN. Moreover, vector control implementation may be hampered by social distancing
and mobility restrictions as well as by limited community acceptance of these interventions
over fears of viral contagion (IRS, in particular, requires workers to enter houses
to spray the inner walls, hence it can be perceived as invasive).
Modelling has estimated that, given worst-case scenarios of disruptions of malaria
interventions, including ITN and IRS, there could be up to a fourfold increase in
malaria mortality in the region within the next year or more malaria deaths in 2020
than all malaria deaths reported globally in 2000.7 8 This would represent rolling
back 20 years of progress in malaria control. Even considering less extreme scenarios,
the burden of malaria in SSA during the pandemic will remain greater than that of
COVID-19 itself, and plausibly worse than it would have been in the absence of the
pandemic.
The ultimate objective for malaria-endemic countries should be to sustain vector control
interventions at high coverage to allow for community-level protection (canonically,
the recommended coverage has been to protect at least 80% of the population). Some
key strategies to achieve this critical goal are proposed (box 1). We obtained available
country-specific information on the scheduling and completion of vector control campaigns
in SSA in 20209 10 (table 1). With respect to IRS, these data show that, by the end
of August, at least 10 countries had completed IRS rounds, spray campaigns were ongoing
in 2 and 5 had definitive plans for implementing rounds later in the year. Sixteen
other countries had scheduled IRS rounds this year but no information on these was
publicly available.7
Box 1
Strategies required for sustaining malaria vector control interventions during the
COVID-19 pandemic
Ensure that funding for malaria control activities remains in place considering increased
demand of additional resources to carry out activities.
Secure timely procurement of commodities (mainly insecticide-treated nets and indoor
residual spraying insecticides) and personal protective equipment for frontline workers.
Implement training programmes according to new guidelines that consider the risks
of COVID-19 transmission during control activities and ensure compliance of frontline
workers with established COVID-19 prevention protocols.
Reinforce social behaviour change and communication campaigns to increase acceptance
of vector control by the community.
Facilitate remote technical assistance for the implementation of interventions.
Implement adaptive management of vector control allowing recurrent review of strategic
plans in light of unforeseen circumstances during the pandemic.
Engage community leaders and authorities in strategic plans in order to facilitate
community acceptance of interventions.
Table 1
State of ITN distribution and IRS campaigns in 2020 among malaria-endemic countries
of SSA at the time of writing
Intervention
ITN distribution
IRS round
Planned countries, according to WHO7 (n)
28
33
Countries with available data (n) (PAR (millions))§
19(562.3)
17(460.6)
Completed countries (n)
7
10
Ongoing countries (n)
5
2
Scheduled countries (n)
7
5
Population targeted (million people) (% of PAR)*
205.1(36.5)
NA‡
Population protected (million people) (% of PAR)†
60.0(10.7)
NA‡
Population protected/targeted (%)*†
29.3
NA‡
ITN procured in 2020 (million nets)
90.7
–
ITN confirmed for distribution (million nets)
122.2
–
ITN already distributed (million nets)†
34.3
–
Specific, country-level data were obtained through online resources and personal communication
with implementing agencies (PMI VectorLink Project for IRS (https://pmivectorlink.org)
and The Alliance for Malaria Prevention for ITN (https://allianceformalariaprevention.com).
Planned and available data country counts include Equatorial Guinea to account for
interventions implemented on Bioko Island.
*Data available for 16 countries at the time of writing.
†Data available for five countries that had completed the scheduled campaigns and
for four that had ongoing ITN distributions at the time of writing.
‡NA; no country-specific data on populations targeted and protected were available
at the time of writing.
§Population at risk of malaria, 2018 estimate.
IRS, indoor residual spraying; ITN, insecticide-treated nets; PAR, Population at risk;
SSA, sub-Saharan Africa;
IRS, indoor residual spraying; ITN, insecticide-treated nets; PAR, Population at risk;
SSA, sub-Saharan Africa.
Regarding ITN, at least seven countries had successfully completed distribution by
the end of August 2020. Twelve other countries had partially completed campaigns or
had rescheduled them for later in the year. A total of 34.3 million ITN had been distributed,
protecting 60.0 million people in the targeted areas and at least another 87.9 million
ITN are planned for distribution, targeting another 134.1 million people. At the time
of writing, five countries specifically reported delays due to COVID-19 and one had
postponed distribution for 2021. Another 10 countries had planned ITN distributions
in 2020,7 but we could find no information on these campaigns. Importantly, 90.7 million
ITN had been procured in the first half of 2020, a figure comparable to the average
net procurement by quarter in 2018 (43 million) but lower than in 2019 (53 million).
These figures are encouraging as they show that countries are pushing for sustaining
vector control despite the dire circumstances determined by the COVID-19 crisis. They
also reveal, however, that much work is still needed to protect the lives of millions
of people at risk of malaria in SSA. For instance, in Nigeria, the SSA country with
the highest population at risk of malaria (>200 million people), only 11.1% of the
22.7 million nets in the distribution plans have been so far distributed. Disruptions
to ongoing campaigns would block 34 million people access to a life-saving bed net.
Mozambique has scheduled both IRS and ITN in 2020, yet none of the campaigns had started
at the time of writing. The Mozambican population targeted to receive ITN is 20.9
million, or roughly 70% of the population at risk of malaria in the country. The stakes
are high.
What the figures fail to convey are the intricate difficulties that malaria control
programmes are facing when implementing vector control interventions during the pandemic.
Our own work on Bioko Island, Equatorial Guinea, helps illustrate these challenges
to better grasp the complexity of the situation. Between February and July 2020, both
IRS and ITN campaigns were conducted on Bioko given that government and donor funding
were prioritised while additionally supporting the COVID-19 response. The vector control
teams were trained for best practices to reduce the risk of viral infection, including
transmission prevention strategies, social distancing during activities and sanitisation
protocols. All field workers were equipped with requisite personal protective equipment.
In March 2020, the government declared a countrywide state of emergency and interdicted
mobility between districts. Later on in the campaign, several IRS operators tested
positive for COVID-19 and had to isolate, significantly reducing the workforce. Social
distancing measures required more time and resources to mobilise teams. In addition,
increased community refusal to spray operations and mobility interdiction forced repeated
changes to deployment plans.
Thanks to the ability to quickly adapt operations in response to these changing circumstances,
vector control interventions on Bioko Island were neither seriously delayed nor interrupted,
but the IRS campaign did suffer significant setbacks, with decreased productivity
(each worker sprayed 3.2 houses per day in 2020 compared with an average of 4.1 houses
per worker per day in the previous three rounds) and suboptimal coverage (74.6% of
households were sprayed in targeted communities in 2020 compared with a 79.2% average
coverage in the previous three rounds). Given the less intrusive nature of ITN distribution,
no major difficulties were encountered, achieving an overall coverage of 89.1% of
the targeted households. These accounts attest to the huge challenges faced by vector
control teams due to the COVID-19 pandemic that can threaten the completion of campaigns.
The risk of malaria resurgence often remains high in places where gains against the
disease have been achieved, such as is the case in much of SSA.11 12 This is due to
the high intrinsic potential for malaria transmission, which determines that these
gains are usually fragile and underscores the need to sustain vector control.12 To
this end, the commitment from governments, funding agencies, non-governmental organisations
and individuals to malaria control has been and continues to be instrumental during
the pandemic. National malaria control programmes must commit to maintaining activities,
while governments must show strong leadership and secure the necessary funds to guarantee
implementation and the procurement of commodities. Funding agencies must not falter
in providing critical financial resources in light of the increasing demand for supplies
and the unprecedented economic contraction. International organisations must work
harder to deliver the technical support required to devise new strategies and to develop
necessary tools. Individuals who implement vector control must be lauded for their
efforts, as they are putting their safety at risk to prevent malaria and safeguard
the lives of millions of people living in malaria-endemic areas.
The worst may well be yet to come in the COVID-19 pandemic13 and its impact may take
years to dissipate.14 Meanwhile, SSA countries cannot afford to relax their efforts
at malaria control to avoid woeful health consequences from this disease on top of
the potential devastation of COVID-19. This pandemic is very far from over and other
severe pandemics will likely follow before countries achieve malaria elimination.15
If COVID-19 is to teach us something about malaria, it should be how to keep up the
fight against this old scourge during the hardest of times. This could also serve
as an opportunity to boost the priority that malaria control deserves in the global
public health agenda in normal times.