SLIDE 1 HIP conference, Oxford, July 2014
Laura Guerrero-Latorre (University of Barcelona) Rosina Girones (University of Barcelona) Simone Carter (OXFAM Intermon)
SLIDE 2 Ø Hepatitis E Virus (HEV) characteristics & epidemiology Ø Current protocols for water disinfection in emergencies Ø Present results water disinfection treatments for HEV
Chlorine
UV Flocculant-chlorine sachets
Ø Environmental investigation South Sudan 2013
Session Contents
SLIDE 3 Hepatitis E Virus characteristics & epidemiology
0,5% population 25% pregnant women
Imunosuppressed patients
WHO 3.000.000 cases & 56,600 deaths per year
SLIDE 4
Hepatitis E Virus characteristics & epidemiology
Reported outbreaks (until 2013)
SLIDE 5 Current protocols for WASH interventions in HEV epidemics
WASH activities in HEV epidemics will focus on:
- Water treatment
- UNHCR recommends chlorination1
(0.8-1 mg/l at tapstands)
- WHO recommends boiling or chlorination2
- MSF recommends UV treatment3
- Water quantity (20 liters/person/day)
- Sanitation (1:20 latrines : people, reduce open defecation)
- Hygiene promotion (basic hygiene measures at communal,
household and individual levels)
- 1. UNHCR. Field Brief: Hepatitis E Response In Refugee Settings 2014
- 2. WHO. Manual on Response to Outbreaks of Hepatitis E in Limited Resource Settings (draft). 2013
- 3. MSF. Public Health Engineering in Precarious Situations. 2010
SLIDE 6
Problem: There is no existing evidence of which is the effective dosage and time of contact of disinfectant (nor for chlorine neither for UV) to inactivate Hepatitis E Virus in water matrices. Solution: Creation of evidence-based Standard Operational Procedures for Hepatitis E Virus Water Disinfection in Humanitarian Context
SLIDE 7 Phase 1: In vitro model for testing infectious virus stability and infectivity
Ø
Methodology Viral strains Hepatitis E Virus
- Sar55 Genotype 1 (experimentally infected rhesus macaque)
- Kernow-C1 p6 Genotype 3 (patient infected) (kindly provided by Emerson
S.)
Cell culture lines
- Caco-2 (human epithelial colorectal adenocarcinoma cells)
- HepG2/C3A (human epithelial hepatocellular carcinoma)
Surrogate viruses
- Human Adenovirus (HAdV)
- Bacteriophage MS2 (MS2)
Water disinfection treatments for HEV
SLIDE 8 Phase 2: Describe kinetics of disinfection for Chlorine treatment, UV treatment and rapid flocculation + chlorination sachets.
ImmunoFluorescence Assay (IFA)
- Different water matrices assayed
- Viral doses quantified by:
- ImmunoFluorescence Assay (IFA)
- Quantitative RT-PCR (qRT-PCR)
- Plaque Assay
Quantitative RT-PCR (qRT-PCR)
Water disinfection treatments for HEV
SLIDE 9 Water disinfection treatments for HEV
Chlorine treatment
BDF water pH 8 BDF water pH 8 BDF water pH 8 + 1% sewage
1.97 x 103 ffu/mL2.04 x 104 ffu/mL 1.86 x 103 ffu/mL 7.3 mg/L 5.8 mg/L 23.1 mg/L
Initial concentration FRC (t0) Hepatitis E Virus concentration
Cell culture Pooled faeces
Hepatitis E Virus origin
1.1 mg/L 1.1 mg/L 2.5 mg/L
Residual concentration FRC (t0.5)
2 4 6 8 10 12
Chlorine decay
minutes mg/L
0.9 mg/L 1 mg/L 1.4 mg/L
Residual concentration FRC (t30)
Cell culture
SLIDE 10 Chlorine treatment Results
Virus tested Experimental condition Viral initial concentration (FFU/ml) Initial free chlorine (mg/l) R2
1-log 2-log 3-log 4-log
T90 C(t) T99 C(t) T99.9 C(t) T99.99 C(t) HEV viruses from cell culture 1.97 x 103 7.3 0.61 0.02 0.15 NR NR NR viruses from pooled faeces 2.10 x 104 5.8 0.77 0.02 0.12 0.07 0.41 NR NR +1% sewage 1.86 x 103 23.1 0.98 0.22 5.09 0.49 11.21 NR NR HAdV2 high viral load 7.20 x 105 2.7 0.96 0.27 0.73 0.35 0.95 0.44 1.19 0.61 1.65 viruses from cell culture 1.40 x104 5 0.82 0.23 1.15 0.78 3.9 NR NR viruses from cell culture 1.40 x 104 2.2 0.89 0.36 0.79 NR NR NR
C(t) = concentration x time mg/L min Efficiency factor Hom (EFH) model was used to predict Ct values
Equivalent to 1E+06 infective viruses in 100 ml
Water disinfection treatments for HEV
SLIDE 11 UV treatment
Assays performed in collaboration with Regina Sommer From the Medical University of Vienna
Beaker 1 Water, pH 8, < 10 NTU 7.9 x 102 ffu/mL
Water matrix Hepatitis E Virus concentration
0-100-200-300-400- 500-600-700-800- 1000-1400 m2/J
UV fluences
1 10
Fluence (J/m2) pfu/mL
Infectivity
MS2 bacteriophage
200 400 600 800 1000 1200 1400 1 10 100 1000 10000 100000 1000000 10000000 100000000 1000000000
Fluence (J/m2) GC or ffu / mL
Infectivity Molecular quantification
Hepatitis E Virus 95.9 % reduction of infectious HEV
Water disinfection treatments for HEV
SLIDE 12 Tap water pH 7, NTU < 5
3.74 x 104 PUR WaterMaker
Treatment Hepatitis E Virus concentration (GC/mL) River water pH 9, NTU > 30
3.74 x 104 8.96 x 104 8.96 x 104 PUR WaterMaker 91.39% 79.58% 93.48% 91.51%
Reduction HEV PURTM Purifier of Water Contents: Fe2(SO4)3: 352 mg Fe(III); Ca(OCl)2 WaterMakerTM Contents: 1.4% available chlorine and approved flocculants
99.18% 99.84% 99.58% 99.83%
Reduction MS2 (5 assays)
Water disinfection treatments for HEV
Tap water pH 7, NTU < 5 River water pH 9, NTU > 30
SLIDE 13
Summary
Treatment recommendations of 0.5 mg/l Free Residual Chlorine after 30 min of contact time will reduce HEV (infective particles) in at least 99% With an exposure to 100 J/m2 in a 253.7nm low pressure lamp HEV (infective particles) reduces in 95.9% After treatment with sachets in turbid water (> 30 NTU) HEV (viral particles) reduces : 79.6% (PURTM) and 91.5% (WaterMakerTM)
Water disinfection treatments for HEV
SLIDE 14
Environmental investigation South Sudan 2013
SLIDE 15
The environmental investigation focused on two camps : Jamam and Batil. Water samples at Surface Level (8), Groundwater Level (7), Household Water Level (8) and Household Food Level for testing on Human Adenovirus & Hepatitis E Virus Batil camp Jamam camp
Environmental investigation South Sudan 2013
SLIDE 16 Environmental investigation South Sudan 2013
J Water Health. 2011 Sep;9(3):515-24.
Results The presence of HAdV in some water sources studied indicate potential routes of faecal contamination for water-borne viruses
SLIDE 17
Environmental investigation elucidates the potential sources and patterns of HEV transmission in the affected camps during the study period showing ….
Results
High risk of transmission at Household level…
Those results are independent of the potential role of flooding may have on the microbiological quality of water sources
SLIDE 18
Intermon Oxfam & University Barcelona Research Platform
Acknoledgements Anna Carratalà, University of Barcelona Regina Sommer, Medical University of Vienna Suzanne Emerson, National Institutes of Health, USA Miquel Calvo, Statistics Department of University of Barcelona Joe Brown and Jeroen Ensink , London School of Hygiene and Tropical Medicine Peter Maes and William Ettiene, Mediciens Sans Frontieres Belgium Jose Dvorzak and Nina Egger-Bussing, Mediciens Sans Frontieres Holland Alberto Ibañez, Intermon Oxfam
