The distribution of long-lasting insecticide-treated nets
and water filters to prevent malaria and water-borne diseases can significantly
reduce the rate of HIV disease progression among Kenyan adults not yet eligible
for treatment, an international research group reported on Wednesday at the 19th International AIDS Conference (AIDS 2012) in Washington DC.
Receipt of these items was associated with a 27% reduction
in the risk of reaching the CD4 cell threshold for starting treatment among
people living with HIV, but not yet eligible for treatment, during two years of
follow-up of a prospective cohort, reported Judd Walson, Associate Professor in
the Department of Global Health at the University of Washington, Seattle.
A related study estimated that, if the same effect were seen throughout
sub-Saharan Africa after the distribution of these products to people living
with HIV, the intervention would have the potential to save just over US$400
million a year in antiretroviral treatment costs, if all adults were able to
start treatment when their CD4 cell counts fell below 350 cells/mm3.
Both malaria and water-borne infections have been proposed as
influencing HIV disease progression, but previous evidence about their effects
has been mixed. Unclean water is the major source of infectious causes of
diarrhoea in people with HIV, while malaria can cause temporary increases in
The study examined the impact on the health of people living
with HIV infection of receiving the insecticide-treated net and water filters
during a multi-disease prevention campaign in communities in western Kenya.
The multi-disease prevention campaign was designed to
promote the prevention of three causes of disease associated with high levels
of morbidity and mortality in many regions of sub-Saharan Africa.
A prevention programme that can address all three diseases
is likely to have greater reach and achieve substantial economies of scale as a
result of the distribution of prevention commodities targeting the three
different diseases through one distribution channel.
The data presented this week in Washington show that the
prevention of malaria and water-borne diseases has an impact on the health of
people living with HIV, and also has the potential to save money, by delaying
the start of treatment in settings where the numbers needing treatment may
exceed the funds available to provide immediate treatment for all who are
In the Kenyan pilot study, conducted in western Kenya, the Ministry
of Health partnered with local community groups and an international NGO to run
a multi-disease prevention campaign, which advertised free HIV counselling and
testing at central locations in the largely rural district, during a one-week
campaign that used community mobilisation activities to raise awareness of the
opportunity for HIV testing.
Everyone who attended the campaign events was offered
voluntary counselling and testing. Previous reports from the campaign showed
very high uptake, of around 99% among those who received the care package.
Four per cent of those who underwent HIV testing tested
positive in the first campaign in 2008, and previously published research
showed that people who tested during the multi-disease prevention campaign were
diagnosed at significantly higher CD4 cell counts than people diagnosed through
provider-initiated testing and counselling at local hospitals.
Everyone who attended and consented also received a CarePack
– a canvas bag containing a PermaNet long-lasting
insecticide treated net, manufactured by Vestergaard Frandsen, and a LifeStraw water filter,
also manufactured by Vestergaard Frandsen. The CarePack also provided condoms,
and at the campaign events everyone received education on the use of the
insecticide-treated nets, the water filters and condoms, together with general
information about the prevention of malaria, water-borne diseases and HIV
Everyone diagnosed with HIV was linked to care by a 'navigator' – another person living with HIV – to whom they were introduced
through a support group, and subsequently received cotrimoxazole (Septrin) prophylaxis.
In the study presented this week, investigators recruited a
prospective cohort of 589 HIV-positive people with CD4 cell counts above 350
not yet eligible for treatment and without symptomatic HIV disease (WHO stages
3 or 4), of which 361 received the CarePack
intervention. Individuals received HIV care through Kisii Provincial Hospital
and Kisumu District Hospitals.
Quite a high proportion of those in the control group used
both water purification methods and insecticide-treated nets, but the
intervention group had a significantly higher usage of insecticide treated nets
(97.7 vs 83.1%, p<0.001) and were significantly more likely to report that
they slept under it (mosquitoes that spread malaria are most active after dark
and in low light, so using the net consistently at night is a very important
means of protecting against malaria).
People who received the intervention were significantly more
likely to drink purified water (99.5% vs 76%, p<0.001) and reported
significantly different patterns of water safety practices. In the control
group the predominant practice was to use chlorine for water purification
(45.4%), or else to boil water (29.9%), but in the intervention group 93% used
the LifeStraw water filter provided.
Only 5% used chlorine for water purification. (These practices were verified
during a home visit.)
The intervention resulted in a 27% reduction in the risk of
disease progression to a CD4 cell count of 350 or below during the two-year
follow-up period (HR 0.73, 95% confidence interval 0.57 – 0.95), and those in
the intervention group were also at lower risk of reaching a composite endpoint
of either CD4 cell count below 350 or death from non-traumatic cause (HR 0.75,
95% CI 0.58 – 0.79). There was no significant difference in risk after controlling for cotrimoxazole prophylaxis use or toilet type.
The study also found that the extent of CD4 cell decline was
significantly lower among those who received the long-lasting
insecticide-treated nets and water filters (-54 vs – 70 cells/mm3
People in the intervention group were also significantly
less likely to report diarrhoea (HR 0.65), malaria symptoms (HR 0.75) or to be
diagnosed with clinical malaria (HR 0.66).
A new recipient of the LifeStraw Family water filter in Western Province, Kenya. Image © All rights reserved by Vestergaard Frandsen