A 1-Year Quantitative Survey of Noro-, Adeno-, Human Boca-, and Hepatitis E Viruses in Raw and Secondarily Treated Sewage from Two Plants in Norway

Abstract

A study of enteric viruses in raw and treated sewage from two secondary treatment plants, which received sewage from Oslo city (plant A) and small municipalities in Hedmark county in Norway (plant B), showed high levels of noro-, adeno-, and bocavirus throughout the year. A seasonal variation was observed for adeno- and GII norovirus with higher levels during winter and bocavirus that had more positive samples during winter. The virus concentrations in raw sewage were comparable in the two plants, with medians (log10 genome copies per liter) of 6.1, 6.3, 6.0, and 4.5 for noro GI, noro GII, adeno-, and bocavirus, respectively. The level of hepatitis E virus was not determined as it was below the limit of quantification. The mean log10 virus reduction was 0.55 (plant A) and 1.44 (plant B) with the highest reduction found in the plant with longer hydraulic retention time. The adenoviruses were dominantly serotype 41, while serotype 12 appeared sporadically. Of the 102 raw and treated sewage samples that were tested, eight were positive for hepatitis E virus of which four were from treated sewage. Two of the four obtained gene sequences from hepatitis E virus originated from the rural sewage samples and showed high similarity with a genotype 3 strain of hepatitis E virus detected in local piglets. Two other hepatitis E virus sequences obtained from urban sewage samples showed high similarities with genotype 3 strains isolated from urban sewage in Spain and a human genotype 1 isolate from India. The study gives information on the levels of noroviruses in raw and treated sewage, which is valuable to risk assessment, information indicating that some infections with hepatitis E viruses in Norway have a regional origin and that human bocavirus 2 and 3 are prevalent in the Norwegian population.

Membrane Bioreactor-Based Wastewater Treatment Plant in Saudi Arabia: Reduction of Viral Diversity, Load, and Infectious Capacity

“…Estimated abundance appeared to be in concordance with the range reported previously by other investigators. Myrmel and coworkers detected 10 5.8 to 10 6.2 genomic copies/L of AdV in a study conducted in Norway [37], while Kuo et al detected approximately 3.8 ± 0.5 × 10 5 viral particles per liter of raw sewage in Taiwan [38]. Similarly, EV concentrations ranged from 10 2.7 copies/L in a New Orleans, US study [39] and as high as 1.5 × 10 5 to 1.2 × 10 8 copies per L in an analysis done in Japan [3].…”

Treated Greywater Reuse for Hydroponic Lettuce Production in a Green Wall System – Quantitative Health Risk Assessment

“…The base for the estimate of reference pathogen concentration was the combination of information about E. coli in each treatment steps with the concentration of reference pathogens in the sewage system, which was published in different studies. Moreover, 1% of the sewage assumed to be mixed with the greywater system (Table S2), from the previous studies, the average concentration of Cryptosporidium, Campylobacter, and norovirus in the sewage system estimated 678.1 oocysts/100ml, 118 MPN/100ml, and 5.1x10 4 gene copies/100ml respectively [40][41][42]. The concentration of reference pathogens in the irrigation water were dependent on the efficiency of greywater treatment steps of the system, which was based on E. coli removal efficiency.…”

Treated Greywater Reuse for Hydroponic Lettuce Production in a Green Wall System: Quantitative Health Risk Assessment

“…The base for the estimate of reference pathogen concentration was the combination of information about E. coli at each treatment step with the concentration of the reference pathogens in the sewage system, which has been published in different studies. Moreover, with 1% of the sewage assumed to be mixed with the greywater system (Table S2), from the previous studies the average concentration of Cryptosporidium, Campylobacter, and Norovirus in the sewage system was estimated to be 678.1 oocysts/100 mL, 118 MPN/100 mL, and 5.1 × 10 4 gene copies/100 mL, respectively [42][43][44]. The concentration of reference pathogens in the irrigation water was dependent on the efficiency of the greywater treatment steps of the system, which was based on E. coli removal efficiency.…”