Category Archives: Contaminated water

Research -Microbial safety and sanitary quality of strawberry primary production in Belgium: risk factors for Salmonella and Shiga toxin producing Escherichia coli (STEC) contamination

Academia Edu

Hepatitis A kswfoodworld

Strawberries are an important fruit in Belgium both in production and consumption, but little
information is available about the presence of Salmonella  and STEC in these berries, the risk
factor in agricultural production and possible specific mitigation options. In 2012, a survey
was undertaken of three soil and three soilless cultivation systems in Belgium.
No Salmonella spp. was isolated. No STEC was detected in the strawberry samples (0 out of 72), but STEC
was detected by qPCR in 11 out of 78 irrigation water and 2 out of 24 substrate samples.
Culture isolates were obtained for 2 out of 11 qPCR positive irrigation water samples and 2
out of 2 substrate samples. Multivariable logistic regression analysis revealed elevated generic  E. coli
numbers (odds ratio (OR) for 1 log increase being 4.6) as the most important risk factor for STEC, together with the berry picking season (elevated risk in summer). Presence of generic  E. coli in the irrigation water (≥ 1 cfu per 100 ml) was mainly influenced by the type of irrigation water (collected rainfall water stored in ponds was more often contaminated than ground water pumped from boreholes (OR = 5.8)) and the lack of prior treatment (untreated water versus water subjected to sand filtration prior to use (OR = 19.2)). The follow-up study in 2013 at one of the producers indicated cattle as the most likely source of 
STEC contamination of the irrigation water.

Research – A summary of cryptosporidiosis outbreaks reported in France and overseas departments, 2017–2020

Science Direct

water contamination


Cryptosporidium is a known foodborne pathogen, ranked fifth out of 24 among foodborne parasites in terms of importance and a cause of many cryptosporidiosis outbreaks worldwide. In France, very few outbreaks were reported before 2017, and data recently obtained by the Expert Laboratory of the Cryptosporidiosis National Reference Center (CNR-LE-Cryptosporidiosis) have shown that outbreaks are in fact common and frequently underreported. In this work, we aim to report the characteristics of outbreaks detected in France during the period 2017–2020 and present a summary of investigations carried out by the CNR-LE-Cryptosporidiosis. During the study period, there were eleven cryptosporidiosis outbreaks, including three with no identified origin. Among the eight identified outbreaks: six were due to water contamination (five tap water and one recreational water), one was due to direct contact with infected calves, and one was due to consumption of contaminated curd cheese. Among these outbreaks, five of them exceeded one hundred cases. Recent results obtained by the CNR-LE-Cryptosporidiosis revealed the multiannual occurrence of Cryptosporidium outbreaks in France. Waterborne outbreaks were more frequently detected, while foodborne outbreaks which are more difficult to detect were likely underreported.

Syria – Cholera outbreak


Food Illness

cholera outbreak in several regions of Syria presents “a serious threat to people in Syria and the region”, the United Nations representative in the country said, calling for an urgent response to contain its spread.

The outbreak is believed to be linked to irrigation of crops using contaminated water and people drinking unsafe water from the Euphrates river which bisects Syria from the north to the east, UN Resident and Humanitarian Coordinator Imran Riza said in a statement.

Research Paper Sunlight Parameters Influence the Survival and Decline of Salmonella and Escherichia coli in Water

Journal of Food Protection

The effect of variations in temperature, ultraviolet (UV) radiation, and sunlight intensity on generic Escherichia coli , E. coli O157:H7, Salmonella Newport and antibiotic resistant (ABR) variants of E. coli O157:H7 and S . Newport exposed to sunlight was evaluated. Bacterial strains suspended in sterile deionized water at a concentration of 8 log CFU/ml were exposed to sunlight on three different days for 180 min; control treatments were stored in the dark. The mean temperature of 30.08 and 26.57℃ on day 1 and 3 were significantly different (p<0.05). The UV intensity was significantly different on all three days and sunlight intensity significantly differed on day 3 (p<0.05). Bacterial population decline positively correlated with temperature, sunlight and UV intensity. Differences in bacterial population declines differed among specie, antibiotic resistance (ABR) profile and day of exposure. (p<0.05). On days 1 and 2, the populations of generic E. coli dropped below the limit of detection (1 log CFU/ml) while the % of live cells was 67% and 6.6% respectively. The artificial neural network model developed to predict bacterial survival under different environmental conditions suggested that Salmonella cells were more resistant than E. coli . The ABR strains had significantly higher viable cells after sunlight exposure (p<0.05). Sunlight exposed cells resuscitated in TSB varied in maximum population density and maximum growth rate based on bacterial species and presence of antibiotic resistance. Morphological changes such as viable but non-culturable (VBNC) state transition and filament formation was detected in sub-populations of sunlight exposed bacteria. Daily fluctuations in UV and sunlight intensity can result in significant variations in bacterial decline and recovery.

Research – Transmission of Cryptosporidium by Fresh Vegetables

Journal of Food Protection

water contamination

Consumption of fresh fruits and vegetables is increasing thanks to the awareness to the benefits to human health. Vegetables may become contaminated by enteric pathogens (protozoan parasites, bacteria and viruses) by irrigation with contaminated water, fertilization with fresh animal manure or by infected food handlers. Cryptosporidium spp. are fecal-oral protozoan parasites, known to be highly persistent in the environment, which facilitate the transmission of the infectious oocysts. Efficient methods were developed for releasing and concentrating Cryptosporidium oocysts from leafy vegetables and sensitive and specific methods were applied for their enumeration. The aims of this review are to discuss the development and optimization of methods applied to release oocysts from leafy vegetables, the prevalence of Cryptosporidium oocysts on fresh leafy vegetables from various parts of the world and to discuss cryptosporidiosis outbreaks resulting from the consumption of leafy vegetables. Three solutions were used with comparable efficiency to release oocysts from leafy vegetables 1M glycine solution, 0.1% Alconox and filter elution buffer with an efficiency of 36.2%, 72.6% and 44%, respectively. The prevalence of Cryptosporidium oocysts was reported in developed as well as from developing countries, although simple detection methods were applied. Most of the cryptosporidiosis outbreaks were reported in developed countries, which can be related to their efficient surveillance system. Transmission of infectious pathogens, such as Cryptosporidium may be facilitated by fresh vegetables, which are imported and transferred from less developed to highly developed countries and consumed uncooked. Monitoring of Cryptosporidium oocysts by sensitive detection methods may enhance measures to prevent their transmission by freshly consumed vegetables.

Research – Legionnaires’ disease – Annual Epidemiological Report for 2020 Research –


CDC legionella

Executive summary

  • Legionnaires’ disease remains an uncommon and mainly sporadic respiratory infection with an overall notification rate of 1.9 cases per 100 000 population for the EU/EEA in 2020.
  • A small decrease in the annual notification rate was observed, down from the 2.2 cases per 100 000 population reported in 2019.
  • Notification rates remained heterogenous across the EU/EEA, varying from fewer than 0.5 cases per 100 000 population to 5.7 cases per 100 000 population, with the highest rate reported by Slovenia.
  • Four countries (France, Germany, Italy and Spain) accounted for 72% of all notified cases.
  • Males aged 65 years and older were most affected (7.1 cases per 100 000 population).
  • The number of reported cases to the travel-associated surveillance scheme decreased by 67% in 2020 compared with 2019.
  • Only 10% of cases were culture confirmed (10%), likely leading to underestimation of disease caused by Legionella species other than Legionella pneumophila.

Research – An outbreak of cryptosporidiosis associated with drinking water in north-eastern Italy, August 2019: microbiological and environmental investigations



The enteric parasite , along with norovirus,  and rotavirus, is among the most frequent causes of waterborne disease [1,2]. In humans, transmission of  occurs via the faecal-oral route, either through direct exposure to infected people (person-to-person infection) or animals (animal-to-person infection), or through ingestion of water (drinking water, recreational water such as swimming pools, water parks, lakes, rivers) or consumption of raw or undercooked food contaminated with infectious oocysts [3]. Infection may remain asymptomatic or manifest as acute gastroenteritis (> 80% of infected individuals). Symptoms occur 1 to 12 days (mean: 7 days) after exposure and usually last 6 to 9 days. The severity and duration of symptoms are linked to the immune status of the host, and cryptosporidiosis can be life threatening in immunosuppressed individuals [4].

There are many  species that can infect humans, but the vast majority of cases are due to , a zoonotic species that also infects young ruminants, and , which is essentially only a human pathogen [5]. The environmental route of transmission is of high relevance for  [6]. This is due to several factors including: (i) the high survival rate of oocysts in water (more than 24 months at 20°C), (ii) high resistance to disinfection (30 mg/L of free chlorine are needed to achieve 99% inactivation at pH 7, with a recommended value of 0.2 mg/L for drinking water) [6], (iii) low infectious dose (10–132 oocysts in healthy adults [7]) and (iv) low host specificity [5]. Oocysts lose their infectivity when frozen, boiled or heated over 60°C [6].

The ability of  to survive at high chlorine concentrations [8] and, consequently, at the disinfectant concentrations commonly used in water treatment, has always been a challenge for water treatment plant operators. However, other disinfectants, such as chlorine dioxide, ozone, UV rays and filtration have proved to be rather effective in removing . Water safety mainly depends on the combination of different treatment stages, and a multi-barrier approach is a key paradigm for ensuring safe drinking water [6]. Nonetheless, in small water supplies managed by local communities that serve only few thousand people, multi-barrier treatment systems are usually not implemented. Thus, in order to ensure the safety of drinking water, more traditional treatments, e.g. disinfection, are used and water quality is checked against certain regulatory parameters.

During 2017–20, 60 waterborne outbreaks of cryptosporidiosis have been detected in Europe, the majority of which involving treated recreational water (swimming pools) as the vehicle of infection [9]. The number of outbreaks linked to contaminated drinking water has shown a notable decrease in the past decades, although, when occurring, large numbers of individuals may be involved, as exemplified by the outbreaks reported in 2010–11 in Sweden [10,11].

India – Telangana food poisoning cases: In last 26 days, 236 students fell sick due to contaminated food, water 


As many as 236 students studying in various educational institutions in Telangana State suffered food poisoning in the last 26 days due to contaminated food and water.

The data accumulated by the members of the Hakku initiative, a social campaign of the Institute of Perception Studies says that food poisoning incidents happened at 10 places in nine districts in the last month, as stated in a report by The New Indian Express.

Research – Reclaimed wastewater in agriculture: health risk from pathogens on fruit and vegetables?


German Federal Institute for Risk Assessment (BfR) advises against irrigation in certain cases

In Germany, fresh produce intended to be eaten raw that grow close to the ground, such as lettuce, carrots, strawberries or fresh herbs, should not be irrigated with reclaimed wastewater. The German Federal Institute for Risk Assessment (BfR) advises against this, particularly with regard to pathogenic viruses and parasites that can get onto or into the plants via this route. Current data are still insufficient for a conclusive risk assessment. However, there is evidence that certain viruses and single-celled parasites (protozoa) can defy environmental influences and cause diseases via raw fruit and vegetables. “Reclaimed wastewater in agriculture poses a new challenge to food safety,” says BfR President Professor Dr Dr Andreas Hensel. “In order to reduce pathogens as much as possible, we need very good treatment and detection methods.”

Climate change, unpredictable weather patterns and droughts are depleting water resources in Germany and Europe. To counteract this, Regulation (EU) 2020/741 sets minimum requirements for the use of reclaimed wastewater for agricultural irrigation. The EU regulation for water reuse applies from June 26, 2023 and is intended to protect the environment and human and animal health. The BfR has assessed possible health risks from the use of reclaimed wastewater for the irrigation of plant-based foodstuffs with regard to selected pathogenic viruses and protozoa. Particular attention was paid to fruit and vegetables that can be eaten raw, in which any pathogens that may be present are not reduced or killed by heating.

On the basis of available data, the BfR recommends not using reclaimed wastewater to irrigate plants, whose parts intended for raw consumption are growing close to or in the ground. This applies until suitable treatment processes and controls can ensure that the irrigation water does not contain pathogens, especially human-pathogenic viruses or protozoa. Because according to the current state of knowledge, pathogens can get onto or into the edible parts of the plants via all of the irrigation systems considered (subsurface drip irrigation, drip irrigation, furrow irrigation, sprinkler system, hydroponic culture) and cause illness in humans when consumed raw. Depending on the type of pathogen and the state of health of the person affected, the health impairment may vary; severe illnesses are possible in risk groups. Further research is required with regard to the suitability of methods for inactivating or reducing pathogens during wastewater treatment.

In the opinion of the BfR, plants whose raw edible fraction grows far from the soil, for example vineyards and fruit trees, can be irrigated with reclaimed wastewater of quality class A or B, provided that direct contact of the raw edible fraction with the reclaimed wastewater (by selecting a suitable irrigation system) and the irrigated soil is excluded. Since the viruses and protozoa under consideration are heat-sensitive, no adverse health effects due to pathogens in the reclaimed wastewater are to be expected for plant foods that are sufficiently heated before consumption.

RASFF Alert – Illness from Drinking Water


45 people sick due to drinking water Chateau in Sint Hubert – Belgium and Netherlands