Efficiency of hepatitis A virus removal in six sewage treatment plants from central Tunisia.
The efficiency of six Tunisian sewage treatment plants (STP) for the removal of hepatitis A virus (HAV) from wastewater was analysed in order to evaluate the potential risk for human health linked to reuse or discharge of treated wastewater into the environment. The STP utilize different biological wastewater treatments including primary treatment, which involves the physical removal of organic and inorganic solids, and secondary treatment that involves different processes, such as activated sludge or lagoon. Quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) and conventional RT-PCR were used for the analysis of the 325 wastewater samples (163 raw and 162 treated) obtained. Results revealed highest contamination in west-central of Tunisia in raw wastewater with 62.96 % of samples positive for HAV and predominance during winter and autumn, whereas east-central region showed 50.62 % of positive samples with high prevalence from winter through summer. The quantitative analysis revealed a range between 4.29 × 10(1) and 1.24 × 10(5) RNA copies/mL in treated wastewater, showing clearly the inefficiency for total removal of HAV regardless of the treatment method used. The vast majority of HAV sequences belonged to the sub-genotype IA, except one that was assigned to sub-genotype IB.
Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Avenue Avicenne, 5000, Monastir, Tunisia.|Departamento de Microbiología y Parasitología, CIBUS-Facultad de Biología, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
Imen
I
Ouardani
Departamento de Microbiología y Parasitología, CIBUS-Facultad de Biología, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain.|Public Health England, London, UK.
Carmen F
CF
Manso
Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Avenue Avicenne, 5000, Monastir, Tunisia.
Mahjoub
M
Aouni
Departamento de Microbiología y Parasitología, CIBUS-Facultad de Biología, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain. jesus.romalde@usc.es.
Jesús L
JL
Romalde
D030041:Hepatitis A virus / Q000302:isolation & purification*; D006801:Humans; D012367:RNA, Viral / Q000032:analysis / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012621:Seasons; D012722:Sewage / Q000821:virology*; D014416:Tunisia; D019562:Viral Load; D018508:Water Purification
D012367:RNA, Viral; D012722:Sewage
Genotyping; Hepatitis A; Sewage treatment plants; Wastewater; qRT-PCR