by Judd L. Walson, MD, MPH Assistant Professor, Departments of Global Health, Medicine (Infectious Disease), Pediatrics and Epidemiology, University of Washington

1. Evaluation of long-lasting insecticide-treated bed
nets and a point-of-use water filter to delay HIV-1
disease progression in Kenya
Judd L Walson, MD, MPH
Assistant Professor
Departments of Global Health,
Medicine (Infectious Disease), Pediatrics and Epidemiology
University of Washington

2. 0.3 log10 0.5 log10
1.0 log10 increase
increase increase
Increase in
likelihood of
heterosexual 18-20% 26-40% 100%
transmission
Increase in
risk of
progression 24-25% 44% 113%
to AIDS or
death
Intro Background Malaria Helminths Implications Conclusions

3. Effect of modest VL reduction
Gupta et al. JID 2007; 195 (Feb 15).
Intro Background Malaria Helminths Implications Conclusions

4. Study Objectives
PRIMARY: To determine whether the provision of a long
lasting insecticide-treated bed net (LLIN) and a point-of-
care water filtration device to HIV-1 infected ART-naïve
adults in Kenya delays HIV-1 disease progression, as
measured by time to CD4 count <350 cells/mm3 and/or
death.
SECONDARY: To determine the effect of LLIN and a
simple microbiological water purification system on the
incidence of malaria and reported diarrheal disease when
added to the standard regimen of TMP/SMX among
antiretroviral naïve, HIV infected adults in Kenya.

5. Study Recruitment and Eligibility
Recruitment
Public health campaign in Western Kenya for VCT,
which provided LLIN and water filter and HIV care
and treatment clinics in Western Kenya (Kisii
Provincial, Kisumu District Hospitals).
Inclusion Criteria
• 18 years of age or older
• Confirmed HIV-1 infection
• ART naïve
• CD4 count >350 within previous 3 months
• WHO clinical stage I or II
Exclusion Criteria
• Pregnancy
• History of ART (self reported)

6. Participation

7. Use of Intervention
Water purification methods and use of bed nets during study follow-up between cohorts
Intervention Control
N= 361 N= 127*
1 1 1
Est. % Est. % p-value
Water purification methods
% who drink purified water: 99·5 76·0 < 0·001
Purification system:2
% who boil 9·0 29·9 < 0·001
% who use chlorine 5·7 45·4 < 0·001
% who use filter 93·0 0·4 < 0·001
Use of bed nets
% who have a net: 97·7 83·1 < 0·001
% who both have a net and sleep
under it: 97·3 82·4 < 0·001
!

8. Impact on Diarrhea/Malaria
• The use of LLIN/Water Filter reduced self-reported diarrhea
(RR: 0·65; 95% CI: 0·45, 0·93)
• The use of LLIN/Water Filter reduced self-reported malaria
(RR: 0·75; 95% CI: 0·60, 0·93)
• The use of LLIN/Water Filter reduced clinically diagnosed malaria
(RR: 0·66; 95% CI: 0·49, 0·88)

9. Impact on HIV-1 Disease
Progression
Kaplan-Meier plot of time to disease progression by cohort:
Time to CD4<350
1.00
0.75
Probability
0.50
0.25
Control
Intervention
0.00
0 .5 1 1.5 2
Ti me From Enroll ment, Years
Number at risk (Ev ents)
Control 228 (32) 195 (39) 150 (19) 107 (9) 52 (8)
Interv ention 361 (28) 327 (60) 259 (34) 149 (13) 52 (0)

10. Impact on HIV-1 Disease
Progression
Kaplan-Meier plot of time to disease progression by cohort: Time to CD4<350 or Death
1.00
0.75
Probability
0.50
0.25
Control
Intervention
0.00
0 .5 1 1.5 2
T i me From Enroll ment, Years
N um ber at ris k (Ev ent s)
C ontrol 228 (32) 195 (40) 150 (21) 107 (9) 52 (8)
I nt erv ention 361 (30) 327 (61) 259 (35) 149 (14) 52 (0)

11. Results
• The combined intervention resulted in a 27% risk reduction in
HIV disease progression, as measured by CD4 count ≤350
cells/mm3 (HR: 0·73; 95% CI: 0·57, 0·95). This difference
remained significant after adjusting for either toilet type or water
source (HR 0·75; 95% CI: 0·58, 0·97).

12. Acknowledgements
n All the study participants
n University of Washington/KEMRI - Ben Piper, Grace John-
Stewart, Benson Singa, Paul Ndungu, Toney Odhiambo, King
Holmes, Barbara Payne, Barbra Richardson, Margaret Barrett,
Chris Kealy, Rekha Patel, Rowena de Saram, Laura Sangare, Krista
Yuhas, Frankline Onchiri, Patricia Pavlinac, Barbra Richardson,
Phelgona Otieno
n The fantastic study staff in Nairobi
n The staff of all of the study sites
n KEMRI CCR – Dr. Bukusi, Dr. Rashid, Dr. Mpoke
n CDC –Jonathan Mermin, Becky Bunnell, Clement Zeh
n Vestergaard-Frandsen – Navneet Garg, Alexandre Doyen