Discarded plastic wastes in the environment are serious challenges for sustainable waste management and for the delivery of environmental and public health. Plastics in the environment become rapidly ...colonised by microbial biofilm, and importantly this so-called ‘plastisphere’ can also support, or even enrich human pathogens. The plastisphere provides a protective environment and could facilitate the increased survival, transport and dissemination of human pathogens and thus increase the likelihood of pathogens coming into contact with humans, e.g., through direct exposure at beaches or bathing waters. However, much of our understanding about the relative risks associated with human pathogens colonising environmental plastic pollution has been inferred from taxonomic identification of pathogens in the plastisphere, or laboratory experiments on the relative behaviour of plastics colonised by human pathogens. There is, therefore, a pressing need to understand whether plastics play a greater role in promoting the survival and dispersal of human pathogens within the environment compared to other substrates (either natural materials or other pollutants). In this paper, we consider all published studies that have detected human pathogenic bacteria on the surfaces of environmental plastic pollution and critically discuss the challenges of selecting an appropriate control material for plastisphere experiments. Whilst it is clear there is no ‘perfect’ control material for all plastisphere studies, understanding the context-specific role plastics play compared to other substrates for transferring human pathogens through the environment is important for quantifying the potential risk that colonised plastic pollution may have for environmental and public health.
Display omitted
•Human pathogens can colonise environmental plastic pollution.•Persistence and transport of pathogens can be facilitated on plastics.•Experiments need an appropriate ‘control’ to understand potential risk.•No single control substrate can control for all relevant variables.
Crimean-Congo hemorrhagic fever virus (CCHFV) is a WHO priority pathogen. Antibody-based medical countermeasures offer an important strategy to mitigate severe disease caused by CCHFV. Most efforts ...have focused on targeting the viral glycoproteins. However, glycoproteins are poorly conserved among viral strains. The CCHFV nucleocapsid protein (NP) is highly conserved between CCHFV strains. Here, we investigate the protective efficacy of a CCHFV monoclonal antibody targeting the NP. We find that an anti-NP monoclonal antibody (mAb-9D5) protected female mice against lethal CCHFV infection or resulted in a significant delay in mean time-to-death in mice that succumbed to disease compared to isotype control animals. Antibody protection is independent of Fc-receptor functionality and complement activity. The antibody bound NP from several CCHFV strains and exhibited robust cross-protection against the heterologous CCHFV strain Afg09-2990. Our work demonstrates that the NP is a viable target for antibody-based therapeutics, providing another direction for developing immunotherapeutics against CCHFV.
The public health significance of plastics and microplastics in different environmental matrices has mainly focused on the toxicological effects of human ingestion. But these pollutants can also ...harbour pathogenic bacteria as the surfaces of plastics in the environment quickly become colonised by microbial biofilm. This novel microbial habitat has been termed the ‘plastisphere’ and could facilitate the survival and dissemination of important bacterial and fungal pathogens. Importantly, however, the role of plastic pollution as a secondary pathway for the transmission of human pathogenic viruses has never been addressed. Due to the high prevalence of both enteric and respiratory viruses in the population and in the environment, there is significant potential for human viruses to become associated with the plastisphere. In this review we critically evaluate current knowledge on the interaction of human enteric and respiratory viruses with plastic surfaces and identify the main environmental conditions and plastic characteristics that could affect virus survival and persistence in the environment. Our hypothesis is that the plastisphere can enhance the adhesion, survival and dissemination of human pathogenic viruses and potentially lead to more effective transfer and transmission of viral diseases within the environment. We identify key research questions needed to more fully assess the potential human health risks associated with viruses on plastic surfaces. These include understanding, (1) the mechanisms of viral attachment to either naked or biofilm-colonised plastic (2) how the structural characteristics of viruses (e.g., enveloped, or non-enveloped), affect their persistence in the plastisphere, (3) whether the plastisphere offers protection and increases the persistence of infectious viruses in soil, freshwater, and marine environments.
•Plastic surfaces in the environment become colonised by biofilm (the ‘plastisphere’).•Human viruses frequently come in contact with plastics in the environment.•Microbial biofilm can enhance survival and persistence of human pathogenic viruses.•The plastisphere could increase transfer of infectious viruses in the environment.
Within the country of Brazil, Santa Catarina is a major shellfish
producer. Detection of viral contamination is an important step to
ensure production quality and consumer safety during this process. ...In
this study, we used a depuration system and ultraviolet (UV)
disinfection to eliminate viral pathogens from artificially infected
oysters and analysed the results. Specifically, the oysters were
contaminated with hepatitis A virus (HAV) or human adenovirus type 5
(HAdV5). After viral infection, the oysters were placed into a
depuration tank and harvested after 48, 72 and 96 h. After sampling,
various oyster tissues were dissected and homogenised and the viruses
were eluted with alkaline conditions and precipitated with polyethylene
glycol. The oyster samples were evaluated by cell culture methods, as
well as polymerase chain reaction (PCR) and quantitative-PCR. Moreover,
at the end of the depuration period, the disinfected seawater was
collected and analysed by PCR. The molecular assays showed that the
HAdV5 genome was present in all of the depuration time samples, while
the HAV genome was undetectable after 72 h of depuration. However,
viral viability tests (integrated cell culture-PCR and
immunofluorescence assay) indicated that both viruses were inactivated
with 96 h of seawater recirculation. In conclusion, after 96 h of UV
treatment, the depuration system studied in this work purified oysters
that were artificially contaminated with HAdV5 and HAV.
Microplastics in wastewater and surface water rapidly become colonised by microbial biofilm. Such ‘plastisphere’ communities are hypothesised to persist longer and be disseminated further in the ...environment and may act as a vector for human pathogens, particularly as microplastics entering wastewater treatment plants are exposed to high concentrations of pathogenic bacteria. The potential for human viral pathogens to become associated with the plastisphere has never before been quantified. Here, we have used rotavirus (RV) SA11 (a non-enveloped enteric virus) and the enveloped bacteriophage Phi6 as model viruses to quantify binding and recovery from biofilm-colonised microplastic pellets in three different water treatments (filtered and non-filtered surface water, and surface water with added nutrients). Viruses associated with biofilm-colonised pellets were more stable compared to those remaining in the water. While detection of infectious particles and genome copies of RV remained stable over the 48 h sampling period, Phi6 stability was highly impacted, with reduction values ranging from 2.18 to 3.94 log10. Virus particles were protected against inactivation factors when associated with the biofilm colonising microplastic surfaces, and when there was a high concentration of particulate matter in the liquid phase. Although our results suggest that the presence of an envelope may impair virus interaction with the plastisphere, the ability to recover both enveloped and non-enveloped infectious viruses from colonised microplastic pellets highlights an additional potential public health risk of surface waters becoming contaminated with microplastics, and subsequent human exposure to microplastics in the environment.
Display omitted
•Infectious virus particles were recovered from biofilm colonising microplastics.•Virus interaction with biofilm enhanced virus survival compared to the water phase.•Enveloped virus inactivation (biofilm and water) was higher than non-enveloped virus.•Virus-plastisphere interaction could increase virus stability and dissemination.
Sewage-associated plastic wastes, such as wet wipes and cotton bud sticks, commonly wash up on beaches; however, it is unclear whether this represents a public health risk. In this study, ...sewage-associated plastic waste, and naturally occurring substrates (seaweed and sand), were collected from ten beaches along the Firth of Forth estuary (Scotland, UK) and analysed using selective media for the faecal indicator organisms (FIOs) E. coli and intestinal enterococci (IE), and potential human pathogens (Vibrio spp.). Minimum inhibitory concentration (MIC) analysis was used to determine antibiotic resistance in selected strains. FIOs and Vibrio were more often associated with wet wipes and cotton bud sticks than with seaweed, and there was evidence of resistance to several antibiotics. This work demonstrates that plastics associated with sewage pollution can facilitate the survival and dissemination of FIOs and Vibrio and thus, could present an as yet unquantified potential risk to human health at the beach.
•Sewage-associated plastic waste was found on all beaches sampled.•Wet wipes and cotton bud sticks colonised by E. coli, enterococci and Vibrio spp.•FIOs more often associated with wet wipes and cotton bud sticks than with seaweed•Evidence of AMR in bacteria colonising sewage-associated plastic waste
The State of Santa Catarina produces the greatest quantity of edible mollusks in Brazil. To guarantee sanitary qualify, mollusk cultures should be monitored for contamination by pathogenic ...microorganisms. A self-purification or “depuration” system that eliminates
Salmonella enterica serovar Typhimurium contamination from oysters has been developed and evaluated. The depuration process occurred within a closed system, in which 1000
L of water was recirculated for 24
h. The water was sterilized with ultraviolet (UV) light, chlorine, or both together. Oysters (
Crassostrea gigas) artificially contaminated with
S. typhimurium were harvested every 6
h. Samples of oyster tissue were excised and both the presence and numbers of bacteria were determined. Combined UV light and chlorine treatments resulted in total elimination of bacteria within 12
h. Polymerase chain reaction detected bacteria in water exposed to the three treatments. This pioneering study is the first of its kind in Brazil and represents a major contribution to commercial mollusk culture in this country.
This paper reviews recent literature on the abundance and distribution of faecal indicator bacteria and pathogens in shellfish production areas in the state of Santa Catarina, on the subtropical ...coast of Brazil. This state supplies > 95% of the national production of shellfish. Microbiological monitoring data were mapped using GIS and the results compared with those from other countries. Coastal human population is the main predictive parameter for faecal bacteria in the production areas. Temporal variations of the bacteria can also be predicted by solar radiation and rainfall. The prevalence of pathogens such as hepatitis A virus, human norovirus,
Salmonella
spp. and
Vibrio
spp
.
does not differ substantially from that in developed countries. The information reported here can be used to inform development of microbiological risk profiles for shellfish production areas.
Bivalve mollusks are filter feeders and may accumulate human pathogens in their tissues. Many studies demonstrated human diseases associated with bivalve consumption, especially oysters. ...Anomalocardia brasiliana clams are distributed along the Brazilian coastal area and are an exotic ingredient for some typical dishes in Brazil. Even though there are several reports describing the contamination of oysters and mussels with human pathogens, there is a lack of studies reporting contamination of A. brasiliana with human pathogens. An evaluation of natural microbiological contamination in A. brasiliana samples over a period of 18months (November 2014 to April 2016) showed that the bacteria indices were in accordance with Brazilian regulations (E. coli<230MPN and Salmonella sp. absent in 25g of meat). However, the enteric viruses evaluated were detected throughout the analysis period, with the highest result for the hepatitis A virus (HAV); followed by Rotavirus-A (RVA); Human Adenovirus (HAdV) and Norovirus GI (NoV GI). The bioaccumulation of enteric viruses by A. brasiliana during a period of 24h was performed using NoV GI and GII, HAV, RVA and HAdV as models. Interestingly the mollusk demonstrated different uptake behaviors in relation to these viruses throughout the time period. NoV GI was the most adsorbed virus after 24h. HAV concentration was <1% at 3h, but it increased to <10% at 8h, remaining unchanged until 12h, and decreasing to <3% at 24h; HAdV reached its highest concentration at 12h, being released by the animals and lowering to <3% at 24h. RVA bioaccumulation was unstable over time, reaching its highest values after 24h (<5%); NoV GII bioaccumulation remained <1%. Thermal inactivation of HAdV-2 in A. brasiliana was also evaluated. After the usual gentle cooking procedure using different times (0, 1, 1.5, 3 and 5mins), viral infectivity was evaluated using ICC-et-RT-qPCR. The temperature inside the DT remained <80°C over time and after 5min of cooking the HAdV reached a decay of 90% (1 log10). The results showed a real warn to the consumers that can be exposed to infectious human viruses if they eat these clams improperly cooked. HAV was the most detected virus in these animals, which may lead to outbreaks. A. brasiliana exhibited distinct behavior in NoV GI bioaccumulation and persistence, pointing to the need for further studies about the cellular ligands used by these viruses to become attached to these clams.
•A high diversity of human enteric viral pathogens in the Anomalocardia brasiliana clams was found.•Norovirus GI was the most bioaccumulated virus by Anomalocardia brasiliana clams.•Enteric viruses were not efficiently inactivated in Anomalocardia brasiliana clams after usual time of cooking.
PDF
