Reducing Persistent Diarrhea for PLHA with Effective HWT
1. Reducing Persistent Diarrhea for People
Living with HIV/AIDS by Use of Effective
Household Water Treatment Approaches
T. Mahin1 , R. Peletz2 , M. Eliott3 , M. Sackey Harris4
1 Massachusetts Dept. of Environmental Protection
2 London School of Hygiene and Tropical Medicine
3 UNC - Chapel Hill, UNC Water Institute
4 UNC - Chapel Hill, Institute for Global Health & Infectious Diseases
Presented at Water and Health 2012 Chapel Hill, NC, USA
2. Definitions
Persistent Diarrhea (PD) – Generally defined as
diarrhea lasting > 14 days
Chronic Diarrhea (CD) – Generally defined as
diarrhea lasting > 30 days, therefore CD is a
subcategory of PD
PLHA – People Living with HIV/AIDS
ART – Anti Retroviral Therapy
3. Background
PLHA are 4-7 times more likely to have diarrhea
compared to HIV-negative individuals (Mermin 2004)
Persistent and chronic diarrhea associated with
increased mortality for PLHA
Household water treatment (HWT) increasingly
recommended for PLHA
To what extent do recommended HWT technologies
address pathogens of concern?
4. Impact of PD/CD on Mortality Rates
for PLHA not on ART
Persistent diarrhea (PD) is associated with increased
mortality for PLHA not on ARTs.
- Sewankambo 2000 (Uganda) & Chintu 1998 (Zambia)
46% of eligible PLHA not on ART (end of 2011).
UNAIDS 2012
6. Chronic Diarrhea & Mortality Risk for PLHA
(Zambia)
“The HIV-associated chronic diarrhea was associated
with weight loss, malnutrition, and excess mortality.”
Chintu et al. 1998 J. Trop. Med. Hyg., 59(1), pp. 38–41
7. PD/CD at ART Initiation
Impact on Mortality Rates
PD/CD at ART initiation has been associated with
increased early mortality in a number of low &
middle income countries
A meta-analysis of adults initiating ART examined
causes of early mortality (Gupta 2011)
Chronic
diarrhea
TB Wasting Advanced HIV
10-20% 5-44% 5-53% 20-37%
8. Approach Used for This Review
Searched PUBMED & IAS Online Resource Library
for studies on waterborne pathogens for PLHA with
PD/CD in low- or middle-income countries
Determined which waterborne pathogens were most
commonly detected by taking the % of PLHA-PD for
each pathogen in each study & then averaging
studies
Compared results to HWT efficacy in treating most
common pathogens detected
9. Overview of Studies
(low & middle income countries)
PD cases from 10 to 1,800
Region Africa Asia Lain
America
Middle
East
Total
Number of studies 18 17 9 2 46
Study Design Cross-
sectional
HIV+ controls (w/o
diarrhea or PD/CD)
HIV-
controls
Controls of
unclear HIV
status
Number of studies 28 12 5 1
11. 11
Waterborne Pathogen
Infection Rates for
PLHA-PD by Region
Africa
(SSA)
%
Asia
%
Latin America
& Caribbean
%
Middle
East
%
Cryptosporidium 30 20 33 39
Microsporidia 26 21 13 9
Isospora 10 14 15 4
Cyclospora 3 6 34 -
Salmonella 10 7 1 -
E. histolytica 9 8 6 4
Giardia 7 6 9 9
Shigella 12 3 4 -
Rotavirus - 5 8 -
Campylobacter 6 5 4 -
12. Cryptosporidium
AIDS defining illness
PLHA suffered most from Crypto outbreaks in the
USA (Hoxie 1997, Goldstein 1996)
Smaller than Isospora & Cyclospora oocysts
(implications for HWT filtration)
Chlorine is ineffective at inactivating Crypto but
other methods are effective (WHO 2011a)
13. Microsporidia
Microsporidia are zoonotic parasites with resistant
spores than can be transmitted by water, are
currently unregulated by USEPA & are now
proposed for identification as fungi
Microsporidia spores are smaller than
Cryptosporidium oocysts (filter implications)
Microsporidia are moderately susceptible to
chlorine (WHO 2011b, Li & Fayer 2006, Johnson 2003, Wolk 2000)
and flocculation/settling appears to work well (Gerba
2003)
14. Mortality Risk
Microsporidia are likely a significant cause of
chronic diarrhea for PLHA but based on very
limited data Microsporidia may be less of a PLHA
mortality risk than Cryptosporidium (Bern et al. 2005).
Cryptosporidium infection for PLHA with PD was
associated with increased mortality in 3 of the PD
studies in this review that looked at this issue
(Amadi 2001, Mwachari 1998 & Tumwine 2005).
15. Preliminary Recommended HWT Approaches
for PLHA with PD in Low/Middle- Income
Countries
Treatment needs to address pathogens of
concern, including:
Boiling
Use of a household water filter (e.g. ceramic,
biosand, carbon block) followed by chlorination,
Use of a flocculant/disinfectant powder along with
proper settling/decanting.
16. Conclusions
•Waterborne pathogens are associated with PD/CD
in PLHA in low- and middle- income countries
• Cryptosporidium & Microsporidia most commonly
detected and associated with increased mortality
•Very limited data on viruses
•Microsporidia are an emerging pathogen associated
with CD, particularly for PLHA with low CD4 counts
•HWT treatment (and other WASH interventions)
need to address pathogens of greatest concern
17. Upcoming Reviews
Systematic review of enteric infections among PLHA
in sub-Saharan Africa
Systematic review of WASH interventions to improve
health of PLHA
18. References Cited
Amadi et al. 2001 J. Pediatr Gastoenterol Nutr.
Bern et al. 2005 The Journal of Infect. Diseases 191
Chintu et al. 1998 J. Trop. Med. Hyg., 59(1)
Gerba et al. 2003 J Environ Sci Health A Tox Hazard Subst
Environ Eng. Jul;38(7)
Gupta et al. 2011 PLoS ONE Dec.
Johnson et al. 2003 APPLIED & ENVIRONMENTAL MICROBIOLOGY
Li and Fayer 2006 J Eukaryot. Microbiol., 53(S1)
Mwachari et al. 1998 J Infect. July
Rajagopalan et al. 2009 Am J Infect Dis. 5(3)
Sewankambo et al. 2000 AIDS
Tumwine et al. 2005 Am J Trop Med Hyg.
Wolk et al. 2000 Appl Environ Microbiol. Apr;66(4)
WHO 2011a “Evaluating household water treatment options heath-
based targets and microbiological performance specifications”
WHO 2011b - Guidelines for Drinking-water Quality Fourth Edition
WHO 2012 - HIV/AIDS Fact sheet No. 360, July 2012
19. Comparison of Data with Data from
High-Income Countries
An additional 15 studies were found of PD in PLHA
in high-income countries (HICs).
Microsporidia infection rates averaged 25% for HICs
vs. 20% for low/mid-income countries (LMICs),
Cryptosporidium rates were 19% for HICs vs.
27% for LMICs.
All HIC studies were from the 1990s & results may
be different now given higher ART use rates in HICs.