Reducing Persistent Diarrhea for People Living with HIV by Use of Effective Household Water Treatment Approaches
Download as PDF, PPTX1 like1,074 views
The document discusses the impact of persistent diarrhea (pd) and chronic diarrhea (cd) on individuals living with HIV/AIDS (plha), noting their increased vulnerability and associated mortality risks. It highlights the effectiveness of household water treatment (HWT) methods in addressing pathogens linked to diarrhea, particularly cryptosporidium and microsporidia. Recommendations for HWT interventions are presented, emphasizing the need to target the most concerning pathogens to improve health outcomes for plha.
More Related Content
Similar to Reducing Persistent Diarrhea for People Living with HIV by Use of Effective Household Water Treatment Approaches (20)
Reducing Persistent Diarrhea for People Living with HIV by Use of Effective Household Water Treatment Approaches
- 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
- 5. Chronic Diarrhea, PLHA & Mortality (Uganda) Adapted from Sewankambo et al. AIDS 2000
- 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
- 10. % Positive (all data for low/mid Income countries) 10 Symptomatic Asymptomatic Waterborne Pathogen No. PD Studies Mean % Range Mean % Range Cryptosporidium 40 27% (3 – 74%) 9% (0-50%) Microsporidia 22 21% (0 -77%) 5% (0-25%) Isospora 28 13% (1-41%) 2% (0-6%) Cyclospora 13 8% (1-34%) <1% 0-2% Salmonella 13 8% (0-19%) 6% (0-17%) E. Histolytica 14 7% (0-23%) 4% (0-20%) Giardia 24 7% (0-22%) 6% (0-16%) Shigella 10 7% (0-22%) 3% (1-5%) Rotavirus 2 7% (5-8%) 2% (0-3%) Campylobacter 7 5% (0-13%) 0% -
- 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.