Biotic Relations Between Pathogenic Leptospires And Green Algae

Leptospira interrogans spirochetes belong to a group of pathogens of particularly dangerous infections that cause leptospirosis in many species of wild, farm and domestic animals, as well as humans. Significant economic damage caused by this disease to livestock around the world, numerous cases of death from leptospirosis, and mainly waterborne transmission of the infection determine the topicality of studying all the aspects of the existence of L. interrogans in freshwater ecosystems. The objective of our study was to determine the nature of ecological relationships between L. interrogans and green algae. We used green algae of the Desmodesmus brasiliensis species as a model object. In the experiments, sterile algae culture filtrates were added to L. interrogans containers grown at 27–28 °C. Comparison of the content of spirochete cells in the experiment and control samples, conducted 24 hours after exposure, showed that the reproduction of L. interrogans is markedly inhibited in the samples containing algae secretions at the dilutions of 1:10 and 1:100. In order to reduce resistance to the allelopathic influence of D. brasiliensis algae, leptospira strains were located as follows: Pomona, Australis, Hebdomadis, Canicola, Sejroe, Icterohaemorrhagiae, Grippotyphosa, Tarassovi. The obtained results indicate a complex intraspecific structure of L. interrogans and their high ecological plasticity. In addition, experimental data indicate that, due to the release of biologically active substances into the aquatic environment, green algae have the potential to affect the dynamics of a number of leptospirosis pathogens in situ. Given the important epidemiological and epizootic significance of pathogenic leptospira, further research is necessary to determine the patterns of their interactions and existence in the environment.

Monitoring the incidence and causes of disease potentially transmitted by food in Australia: Annual report of the OzFoodNet network, 2016

In 2016, a total of 44,455 notifications of enteric diseases potentially related to food were received by state and territory health departments in Australia. Consistent with previous years, campylobacteriosis (n = 24,171) and salmonellosis (n = 18,060) were the most frequently-notified infections. Notable increases in incidence were observed for shiga toxin-producing Escherichia coli (n = 343; 166% increase), shigellosis (n = 1,408; 93% increase), campylobacteriosis (33% increase) and salmonellosis (30% increase) when compared with the historical five-year mean. The extent to which the introduction of culture-independent testing as a method of diagnosis has contributed to these increases remains unclear. In total, 188 gastrointestinal outbreaks, including 177 foodborne outbreaks, were reported in 2016. The 11 non-foodborne outbreaks were due to environmental or probable environmental transmission (nine outbreaks) and animal-to-person or probable animal-to-person transmission (two outbreaks). No outbreaks of waterborne or probable waterborne transmission were reported in 2016. Foodborne outbreaks affected 3,639 people, resulting in at least 348 hospital admissions and four deaths. Eggs continue to be a source of Salmonella Typhimurium infection across the country: 35 egg-related outbreaks, affecting approximately 510 people, were reported across six jurisdictions in 2016. Three large multi-jurisdictional Salmonella outbreaks associated with mung bean sprouts (n = 419 cases); bagged salad products (n = 311 cases); and rockmelons (n = 144 cases) were investigated in 2016. These outbreaks highlight the risks associated with fresh raw produce and the ongoing need for producers, retailers and consumers to implement strategies to reduce potential Salmonella contamination.

SARS–CoV–2 and Food—How Confident Are We about Them?

The recent COVID-19 pandemic and coronaviruses have been thrust into the lives of humans around the globe. Several concerns of the scientific community, authorities and common people have been aroused concerning the prophylaxis measures that need to be taken in order to safeguard public health. Among others, the possibility of a faecal—oral route, and consequent waterborne or foodborne transmission, have been given little attention. Ground zero was the seafood market of Huanan in Wuhan, China; therefore, it was quite logical at the time to assume a certain degree of relationship between water, seafood and SARS–CoV–2. In this manuscript, a critical review of the current literature concerning these routes of transmission is made. The main questions discussed are whether (i) SARS–CoV–2 can infect food animals, (ii) it can be detected in water, retaining its infectivity for the necessary amount of time, (iii) there is a possibility of contamination of food by SARS–CoV–2 through its various production processes and (iv) there is evidence of foodborne or waterborne transmission.

Systematic Review of Hepatitis E Virus in Brazil: A One-Health Approach of the Human-Animal-Environment Triad

Brazil is the fifth largest country in the world with diverse socioeconomic and sanitary conditions, also being the fourth largest pig producer in the world. The aim of the present systematic review was to collect and summarize all HEV published data from Brazil (from 1995 to October 2020) performed in humans, animals, and the environment, in a One Health perspective. A total of 2173 papers were retrieved from five search databases (LILACs, Mendeley, PubMed, Scopus, and Web of Science) resulting in 71 eligible papers after application of exclusion/inclusion criteria. Data shows that HEV genotype 3 (HEV-3) was the only retrieved genotype in humans, animals, and environment in Brazil. The South region showed the highest human seroprevalence and also the highest pig density and industry, suggesting a zoonotic link. HEV-1 and 2 were not detected in Brazil, despite the low sanitary conditions of some regions. From the present review we infer that HEV epidemiology in Brazil is similar to that of industrialized countries (only HEV-3, swine reservoirs, no waterborne transmission, no association with low sanitary conditions). Hence, we alert for the implementation of HEV surveillance systems in swine and for the consideration of HEV in the diagnostic routine of acute and chronic hepatitis in humans.

Monitoring the incidence and causes of diseases potentially transmitted by food in Australia: Annual report of the OzFoodNet network, 2013–2015

This report summarises the incidence of diseases potentially transmitted by food in Australia, and details outbreaks associated with food that occurred during 2013–2015. OzFoodNet sites reported an increasing number of notifications of 12 diseases or conditions vthat may be transmitted by food (botulism; campylobacteriosis; cholera; hepatitis A; hepatitis E; haemolytic uraemic syndrome (HUS); listeriosis; Salmonella Paratyphi (paratyphoid fever) infection; salmonellosis; shigellosis; Shiga toxin-producing Escherichia coli (STEC) infection; and Salmonella Typhi (typhoid fever) infection), with a total of 28,676 notifications received in 2013; 37,958 in 2014; and 41,226 in 2015. The most commonly-notified conditions were campylobacteriosis (a mean of 19,061 notifications per year over 2013–2015) and salmonellosis (a mean of 15,336 notifications per year over 2013–2015). Over these three years, OzFoodNet sites also reported 512 outbreaks of gastrointestinal illness caused by foodborne, animal-to-person or waterborne disease, affecting 7,877 people, and resulting in 735 hospitalisations and 18 associated deaths. The majority of outbreaks (452/512; 88%) were due to foodborne or suspected foodborne transmission. The remaining 12% of outbreaks were due to waterborne or suspected waterborne transmission (57 outbreaks) and animal-to-human transmission (three outbreaks). Foodborne and suspected foodborne outbreaks affected 7,361 people, resulting in 705 hospitalisations and 18 deaths. Salmonella was the most common aetiological agent identified in foodborne outbreaks (239/452; 53%), and restaurants were the most frequently-reported food preparation setting (211/452; 47%). There were 213 foodborne outbreaks (47%) attributed to a single food commodity during 2013–2015, with 58% (124/213) associated with the consumption of eggs and egg-based dishes.

Seafood associated human pathogenic non-enveloped viruses

Non-enveloped human pathogenic viruses, highly stable in the environment, can be transmitted by different routes, such as contaminated food and water. The waterborne transmission of non-enveloped viruses to humans causes illnesses when individuals are exposed to contaminated water resources such as agricultural water, drainage, outdoor water, field or subsurface water and even drinking water. In addition to waterborne transmission, viral foodborne transmission may consist because of contagious seafood, through infected food handlers due to inadequate hygienic activities, aerosol containing viruses produced by infected people. Most hazardous non enveloped enteric viruses assocated with water and seafood cause a significant and emerging food safety and public health problem and threat. In this review, norovirus (NoVs), hepatitis E virus (HEV) and hepatitis A (HAV), human adenovirus, rotavirus A and sapovirus are evaluated as seafood associated human pathogenic non-envoleped viruses.

Predominance of human bocavirus genotypes 1 and 2 in oysters in Thailand

Human bocavirus (HBoV) has been recognized as one of important pathogens of respiratory infection and acute gastroenteritis in young children worldwide. HBoV is most likely transmitted by the respiratory route and fecal-oral transmission. Recently, HBoV has been detected in several types of environmental water and bivalve shellfish. However, study of the existence of HBoV in oyster is still undocumented in Thailand. In this study, 144 oyster samples collected from different markets in Chiang Mai, Thailand during 2017 to 2018 were investigated for the presence of HBoV by nested-PCR and sequencing. HBoV was detected in 11 out of 144 samples (7.6%). Nine HBoV-positive samples (81.8%) were identified as genotype 1 (HBoV1) and two (18.2%) as HBoV2. A monthly investigation of HBoV in oyster samples from July 2017 to June 2018 showed that HBoV was sporadically detected in some particular months spanning the rainy and colder season with its peak in January. This study demonstrates the presence and genotype diversity of HBoV in oyster samples in Thailand. The finding contributes to evaluating the risk of foodborne transmission of HBoV and monitoring the outbreak of HBoV in Thailand and other countries. Importance Human bocavirus is recognized as an important cause of respiratory infection and of acute gastroenteritis in children worldwide. Human bocavirus is widely detected in many clinical specimens as well as in several environmental samples. Most of the studies describe the incidence of bocavirus infection in human while only few data are available for the occurrence of human bocavirus in food materials, particularly, in bivalve shellfish. Our findings provide the evidence for the existence and prevalence of human bocavirus in oysters suggesting that further monitoring the potential risk of food and waterborne transmission of this virus to human should be undertaken.

Proteomic Analysis of the Parasitic Cnidarian Ceratonova shasta (Cnidaria: Myxozoa) Reveals Diverse Roles of Actin in Motility and Spore Formation

Myxozoans are widely distributed aquatic obligate endoparasites that were recently recognized as belonging within the phylum Cnidaria. They have complex life cycles with waterborne transmission stages: resistant, infectious spores that are unique to myxozoans. However, little is known about the processes that give rise to these transmission stages. To understand the molecular underpinnings of spore formation, we conducted proteomics on Ceratonova shasta, a highly pathogenic myxozoan that causes severe mortalities in wild and hatchery-reared salmonid fishes. We compared proteomic profiles between developmental stages from inside the fish host, and the mature myxospore, which is released into the water where it drifts passively, ready to infect the next host. We found that C. shasta contains 2,123 proteins; representing the first proteomic catalog of a myxozoan myxospore. Analysis of proteins differentially expressed between developing and mature spore stages uncovered processes that are active during spore formation. Our data highlight dynamic changes in the actin cytoskeleton, which provides myxozoan developmental stages with mobility through lamellipodia and filopodia, whereas in the mature myxospore the actin network supports F-actin stabilization that reinforces the transmission stage. These findings provide molecular insight into the myxozoan life cycle stages and, particularly, into the process of sporogenesis.

A Systematic Review on Various Therapeutic Options for Coronavirus Outbreak

SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) or coronavirus disease that emerged in Wuhan, China's Hubei province. According to a Wuhan citizen, the virus spread from the Wuhan fish market to humans via a form of waterborne transmission. The WHO proclaimed the SARS-CoV-2 Pandemic a global public health emergency in March of the following year. Rather than influencing the individual animals mostly, the movement of humans and a few days later, the infection spread to other parts of the world by the distribution of specimens to animals and by the movement of humans, causing considerable illness in human populations. An estimated one and a total of nearly sixty-eight million two hundred and fifty-six million people have been impacted, including one and a million thousand five hundred and sixty thousand fatalities in more than two hundred countries around the world. As of the present, there are no medicines or vaccinations against the world's first SARS-CoV-2 virus are in clinical trials molecular and cellular studies of CoVs, as well as their care, were reviewed in this latest assessment. Keywords: SARS-CoV-2, WHO, Global pandemic, Human coronaviruses, Pathogenesis, Treatments