Efficiency of hepatitis A virus removal in six sewage treatment plants from central Tunisia

2015 ◽  
Vol 99 (24) ◽  
pp. 10759-10769 ◽  
Author(s):  
Imen Ouardani ◽  
Carmen F. Manso ◽  
Mahjoub Aouni ◽  
Jesús L. Romalde
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Sewage Treatment ◽  
Virus Removal ◽  
Sewage Treatment Plants ◽  
Central Tunisia

scholarly journals Enteric viruses in inlet and outlet samples from sewage treatment plants

2006 ◽  
Vol 4 (2) ◽  
pp. 197-209 ◽  
Author(s):  
M. Myrmel ◽  
E. M.M. Berg ◽  
B. Grinde ◽  
E. Rimstad
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Sewage Treatment ◽  
High Viral Load ◽  
Primary Treatment ◽  
Advanced Treatment ◽  
Secondary Treatment ◽  
Sewage Treatment Plants ◽  
Viral Contamination ◽  
Viral Particles

Samples collected every two weeks from the inlet and outlet of three sewage treatment plants were screened for the presence of noro-, rota-, astro-, adeno-, hepatitis A- and circoviruses by (RT)-nested PCR, and for F-specific bacteriophages by isolation in Escherichia coli Famp. Plants A and B were secondary treatment plants and plant C used primary treatment. Noroviruses were detected in 43%, 53% and 24% of the inlet samples and 26%, 40% and 21% of the outlet samples from plants A, B and C, respectively. Astroviruses, rotaviruses and adenoviruses were more prevalent. Adenoviruses were detected in 96% of inlet and 94% of outlet samples, supporting the potential of these viruses as indicators of viral contamination from sewage. Hepatitis A virus and circoviruses were found only rarely. Reduction of infective viral particles during sewage treatment was evaluated using F-specific bacteriophages. The phages were reduced by, respectively, 99%, 87% and 0% in plants A, B and C, which corresponded to the observed differences in reduction of norovirus positive samples between the same plants. The study shows that the high viral load in sewage results in a discharge to the environment of a large amount of virus despite sewage treatment. On the other hand, the advantage of a more advanced treatment is demonstrated.

scholarly journals Contamination of Foods by Food Handlers: Experiments on Hepatitis A Virus Transfer to Food and Its Interruption

2000 ◽  
Vol 66 (7) ◽  
pp. 2759-2763 ◽  
Author(s):  
S. Bidawid ◽  
J. M. Farber ◽  
S. A. Sattar
Keyword(s):  
Hepatitis A ◽  
Infectious Virus ◽  
Hepatitis A Virus ◽  
Infectious Hepatitis ◽  
Topical Agent ◽  
Food Handlers ◽  
Virus Removal ◽  
Virus Transfer ◽  
Food Borne ◽  
Water Rinsing

ABSTRACT Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm2resulted in transfer of 9.2% � 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% � 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.

Effectiveness of depuration for hepatitis A virus removal from mussels (Mytilus galloprovincialis)

2014 ◽  
Vol 180 ◽  
pp. 24-29 ◽  
Author(s):  
David Polo ◽  
Cristina Álvarez ◽  
Ángeles Longa ◽  
Jesús L. Romalde
Keyword(s):  
Hepatitis A ◽  
Mytilus Galloprovincialis ◽  
Hepatitis A Virus ◽  
Virus Removal

Removal of hepatitis a virus (HAV), poliovirus and MS2 coliphage by coagulation and high rate filtration

1995 ◽  
Vol 31 (5-6) ◽  
pp. 63-68 ◽  
Author(s):  
A. Nasser ◽  
D. Weinberg ◽  
N. Dinoor ◽  
B. Fattal ◽  
A. Adin
Keyword(s):  
Humic Acid ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Cationic Polyelectrolyte ◽  
High Rate ◽  
Sand Column ◽  
Virus Removal ◽  
Jar Test ◽  
Pathogenic Viruses ◽  
Operation Unit

Filtration is considered a mandatory operation unit for the production of pathogen free drinking water from surface sources. This study was undertaken to determine the removal efficiency of enteric pathogenic viruses (hepatitis A virus and poliovirus) by high rate filtration and to determine the suitability of F+bacteriophages as index for the removal of these pathogens. A jar test was used to determine the optimal flocculation dose to be used in the high rate filtration experiments. At an alum concentration of 30 mg/l, the greatest reduction was observed for HAV (88.4%) as compared with poliovirus 1 (47%) and turbidity (61%). Addition of 1 mg/l cationic polyelectrolyte improved the reduction of HAV to 98.3% by flocculation, while the removal of polio 1 and turbidity was not improved. The presence of humic acid at a concentration of 15.3 mg/l interfered with flocculation performance of HAV and turbidity, while the addition of the cationic polyelectrolyte reduced the interference appreciably. High rate filtration (20 m/hr) using a 100 cm long sand column, resulted in reduction of 99%, 93% and 80% of turbidity, MS2 and poliovirus 1, respectively. Addition of polyelectrolyte enhanced the removal of viruses and turbidity. In the presence of humic acid no virus removal was observed by high rate filtration, whereas turbidity removal was unaffected. The removal of MS2 was similar to that of HAV rather than poliovirus 1. High rate filtration was found efficient for the removal of pathogenic viruses and turbidity from surface water. Under all conditions tested the removal of turbidity was greater than that of viruses.

scholarly journals Migration pattern of hepatitis A virus genotype IA in North-Central Tunisia

2015 ◽  
Vol 12 (1) ◽  
pp. 17 ◽  
Author(s):  
Abir Beji-Hamza ◽  
Stefania Taffon ◽  
Salma Mhalla ◽  
Alessandra Lo Presti ◽  
Michele Equestre ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Migration Pattern ◽  
Virus Genotype ◽  
North Central ◽  
Central Tunisia

scholarly journals Detection and Phylogenetic Analysis of Hepatitis A Virus in the Wastewater Treatment Plant of Ekbatan Town in Tehran, Iran

2022 ◽  
Vol 21 (10) ◽  
Author(s):  
Mitra Nasiri ◽  
Zohreh Yousefi Ghalejoogh ◽  
Angila Ataei-Pirkooh ◽  
Farah Bokharaei-Salim ◽  
Seyed Hamidreza Monavari ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Rna Extraction ◽  
Treatment Plant ◽  
Nested Polymerase Chain Reaction ◽  
Treatment Protocols ◽  
Virus Removal

Background: Limited sources of fresh water necessitate the application of health policies for treatment and decontamination of human sewage for further use. A wide variety of infectious agents, including bacteria, fungi, parasites, and viruses, can be found in sewage. Enteric viruses such as hepatitis A virus (HAV) can survive the current treatments and infect susceptible hosts. Objectives: This study aimed to evaluate the HAV contamination in human sewage before and after treatment in the wastewater treatment plant of Ekbatan town in Tehran, Iran, and analyze the phylogenetic properties of the identified viruses. Methods: Over a 12-month period, we collected the wastewater samples including influent, before chlorination, and effluent, from the wastewater treatment plant of Ekbatan town in Tehran, Iran. Ribonucleic acid (RNA) extraction, complementary deoxyribonucleic acid (cDNA) synthesis, and semi-nested polymerase chain reaction (PCR) were performed to identify HAV contamination. Phylogenetic analysis was performed to investigate subgenotypes of the virus. Results: HAV was detected in all influents and samples before chlorination, while the virus was detected in 50% of the effluent samples. All detected viruses belonged to subgenotype IB. Conclusions: Investigating the presence of HAV in sewage provides a general picture of the virus spread in the population of interest. HAV was detected in all influent samples, indicating that the infection is endemic in this area all year round. This also indicates the inability of the current treatment protocols in virus removal, which can be a threat to the public health.

Hepatitis a Virus Levels in Shellfish Exposed in a Natural Marine Environment to the Effluent from a Treated Sewage Outfall

1988 ◽  
Vol 20 (11-12) ◽  
pp. 229-234 ◽  
Author(s):  
Ch Pietri ◽  
B. Hugues ◽  
J. M. Crance ◽  
D. Puel ◽  
C. Cini ◽  
...  
Keyword(s):  
Marine Environment ◽  
Hepatitis A ◽  
Sea Water ◽  
Hepatitis A Virus ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Mussel Sample ◽  
High Concentrations ◽  
Seawater Samples

Hepatitis A virus (HAV) contamination studies and cell-culturable virus determination were undertaken on oysters (Crassostrea angulata) and mussels (Mytilus edulis) kept for six months in the sea near the outfall of a sewage treatment plant. Shellfish and seawater samples were collected on 11 occasions at roughly 15-day intervals during this period. A radioimmunoassay revealed HAV contamination indices (P/N ≥ 2.1) in 3 oyster and 6 mussel samples and 1 sea-water sample. When a radiocompetition test was run on these samples, however, specificity was noted in one mussel sample only (P/N = 2.4). Immune electron microscopy showed that HAV particles were present in three effluent samples. Although a frequent demonstration at sometimes high concentrations (326.0 MPNCU/100 ml) in the effluent was observed, no cell-culturable virus were detected in both the shellfish and the seawater. Adenovirus alone were detected in one mussel sample, but not in the effluent. Complementary studies are now being conducted on all samples with an RIA HAV contamination index of P/N ≥ 2.1. The results of this investigation of viral contamination in a natural marine environment and our HAV detection assays underscore the difficulty of determining the true extent of these phenomena.

Physical Removal and Transfer of Murine Norovirus and Hepatitis A Virus from Contaminated Produce by Scrubbing and Peeling

2013 ◽  
Vol 76 (1) ◽  
pp. 85-92 ◽  
Author(s):  
QING WANG ◽  
MARILYN C. ERICKSON ◽  
YNES ORTEGA ◽  
JENNIFER L. CANNON
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Virus Detection ◽  
Cross Contamination ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Running Water ◽  
Virus Removal ◽  
Food Residue ◽  
Virus Transfer

Human noroviruses and hepatitis A virus are responsible for numerous outbreaks associated with handling fresh produce. In this study, physical removal of hepatitis A virus and murine norovirus, a human norovirus surrogate, from contaminated produce items (honeydew melons, cantaloupes, carrots, and celery) by scrubbing under running water with a nylon brush or scouring pad and by peeling (carrots and celery) with a peeler was investigated. The degree and extent of utensil contamination with viruses during these operations in the presence and absence of food residue also was investigated. Scrubbing or peeling produce initially inoculated with ~5.5 log PFU of each virus resulted in significant levels of virus removal, ranging from 0.93 to 2.85 log PFU. However, utensil cross-contamination occurred, with >2 log PFU of virus transferred from a single produce item. After preparation of a contaminated produce item, utensil cross-contamination resulted in virus detection on seven successively prepared produce items. Produce residue accumulation on utensils variably impacted virus transfer to utensil surfaces. Results indicate that scrubbing and peeling produce can reduce levels of viruses on contaminated produce, but the importance of utensil sanitation to prevent cross-contamination is highlighted. Findings also provide important information for modeling virus cross-contamination during food preparation.

Quantitative Approach of Risk Management Strategies for Hepatitis A Virus–Contaminated Oyster Production Areas

2012 ◽  
Vol 75 (7) ◽  
pp. 1249-1257 ◽  
Author(s):  
A. THEBAULT ◽  
J.-C. LE SAUX ◽  
M. POMMEPUY ◽  
S. LE GUYADER ◽  
R. LAILLER ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Adult Population ◽  
Management Strategies ◽  
Probabilistic Approach ◽  
Sewage Treatment ◽  
Reverse Transcription Pcr ◽  
Negative Results ◽  
Production Areas ◽  
Annual Risk

It is not yet known whether using the new molecular tools to monitor hepatitis A virus (HAV) in shellfish production areas could be useful for improving food safety. HAV contamination can be acute in coastal areas, such as Brittany, France, where outbreaks of hepatitis A have already occurred and have been linked to the consumption of raw shellfish. A quantitative probabilistic approach was carried out to estimate the mean annual risk of hepatitis A in an adult population of raw oyster consumers. Two hypothetical scenarios of contamination were considered, the first for a rare and brief event and the second for regular and prolonged episodes of contamination. Fourteen monitoring and management strategies were simulated. Their effects were assessed by the relative risk reduction in mean annual risk. The duration of closure after abnormal detection in the shellfish area was also considered. Among the strategies tested, results show that monthly molecular reverse transcription PCR monitoring of HAV is more useful than bacterial surveys. In terms of management measures, early closure of the shellfish area without waiting for confirmatory analysis was shown to be the most efficient strategy. When contamination is very short-lived and homogeneous in the shellfish production area, waiting for three negative results before reopening the area for harvest is time wasting. When contamination is not well identified or if contamination is heterogeneous, it can be harmful not to wait for three negative results. In addition, any preventive measures, such as improving sewage treatment or producing shellfish in safer areas, that can reduce contamination by at least 2 log units are more efficient and less costly. Finally we show that controlling and managing transferred shellfish are useful and can play an important role in preventing cases. Qualitative results from HAV monitoring can advantageously supplement other measures that improve the safety of shellfish products in exposed areas.

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