Research round-up: FAIR and Factbook and pathogens in water

We start with the Department of Homeland Security (DHS) Science and Technology Directorate’s (S&T) Office funding the Food Protection and Defense Institute​ (FPDI) to create two interactive, web-based databases with information on adulteration cases and food supply chains.

The databases are available at an individual license subscription cost of $600 per year.

The Food Adulteration Incident Registry (FAIR​) is a searchable collection of current and historical intentional adulteration cases. FAIR captures economically motivated incidents and things such as terrorism, sabotage or revenge.

It also supports food defense efforts by predicting and determining threats based on past incidents.

The information includes affected food products, adulterants used, methods of fraud, health consequences and location of incidents from 1980 to present.

FAIR contains more than 600 adulteration incidents and is growing.

The World Factbook of Food tool identifies food and agriculture activities from farm to fork including high risk foods, average production, trade, common food and non-food uses, standards, value, rankings, seasonality, processing steps and supply chain structure, adulteration and contamination events and product flow.

If a granola bar company needs cinnamon, they can identify major standards, trade flow and global production regions by referencing the World Factbook of Food. The firm can then verify history of intentional adulteration by evaluating cinnamon in FAIR.

FAIR and the Factbook support the Food Safety Modernization Act (FSMA).

“The new regulations in FSMA require companies to assess intentional adulteration including food fraud or economically motivated adulteration that might result public health harm. These two tools…give food companies information in a condensed easily usable format to meet the requirements,”​ said Dr Jennifer van de Ligt, associate director of FPDI.

Salmonella biosensor​

Francisco Javier Uribe Calderón, of the Universidad Autónoma de Querétaro​ in Mexico, has created a gradual and molecular colorimetric nanobiosensor, which detects the DNA of Salmonella spp.

The sensor is made of gold nanoparticles (AuNPs), which highlight the Surface Plasmon Resonance (SPR), which is an optoelectronic phenomenon in which electrons on the surface of the nanoparticle oscillate collectively being excited by an electromagnetic wave like light.

This means that when they are scattered they have a reddish colour but at the moment of joining, they change to blue colour, said Uribe Calderón.

The colorimetric sensor is also gradual as the intensity of the colour varies depending on the concentration of the bacteria. It was tested for dairy products such as cheeses.

Particles are functionalized with DNA strings designed to detect Salmonella.

Breast pump kit contaminated with C. sakazakii​

US researchers reported a Cronobacter sakazakii ​​infection caused by consumption of contaminated expressed human milk which led to meningitis, brain necrosis and developmental delays.

The infant had been fed pasteurized donor human milk and expressed maternal milk (EMM) during the first week after birth and after she received EMM mixed with a commercial liquid human milk fortifier. She did not receive powdered infant formula.

C. sakazakii was cultured from valves of the personal breast pump kit, 11 frozen EMM samples collected using that pump kit during seven separate days before illness onset and the drain of the kitchen sink at the mother’s home.

Cultures of the personal breast pump kit and the 11 frozen EMM samples each yielded two to five additional gram-negative bacteria; other items did not yield pathogens.

Except for the EMM isolate with the earliest collection date, pulsed-field gel electrophoresis patterns of all EMM and clinical C. sakazakii isolates were indistinguishable.

“Although the source of contamination in this case is unknown, a breast pump kit became contaminated with C. sakazakii and was not adequately cleaned or sanitized, leading to contamination of the milk expressed with this kit on several days,” ​said researchers.

“Clinicians should provide detailed recommendations about hygienic expression and handling of human milk to parents who plan to feed EMM to their infants. Settings in which mothers might need to pump their milk, such as hospitals and workplaces, should facilitate hygienic expression and handling of human milk.”​

Cryptosporidium and Giardia​

Researchers from the University of Zaragoza ​​have analysed drinking water and detected oocysts of Cryptosporidium and cysts of Giardia.

Levels detected are very low and do not represent a health risk but ubiquity of the parasites and inefficiency of conventional water treatment in reducing them may present a public health issue.

No limits are set for the concentration of these pathogens in Spanish drinking water regulations.

Scientists analysed the presence of dispersal stages of Giardia (cysts) and Cryptosporidium (oocysts) in drinking water plants in the 20 most populated towns in Aragón.

The study found Cryptosporidium and Giardia in samples from 55% and 70% of drinking water plants, with nine plants positive for both protozoa and four plants negative.

They found one or both pathogens in treated water from seven of the 11 plants with a conventional treatment process (including steps of coagulation; flocculation, or addition of agents that facilitate the subsequent decantation of substances; sedimentation; filtration and disinfection processes).

Joaquín Quílez, one of the paper's authors, said: “Water purification techniques are not completely effective at removing or inactivating these protozoa from water if they pass through the filters, as they are resistant to chlorination. ​

"This means that when there are very high concentrations in the water entering the plant, the treated water may still contain enough quantities of protozoa to trigger a diarrheic outbreak." ​

Finding genomic differences​

University of Georgia​ food scientist Henk den Bakker is fighting pathogens by developing computer software.

Graphs are used to find genomic differences between strains of foodborne bacteria, said den Bakker.

“By studying graphs of complete populations of a pathogen, we can look for genetic variation in genomes that help us to fingerprint bacterial strains. This makes it easier to find bacteria with a similar genomic fingerprint, for instance, bacteria involved in a disease outbreak.”​

He will continue work with UGA CFS researcher Xiangyu Deng and Lee Katz, a bioinformatician at the Centers for Disease Control and Prevention.

The cloud-based SeqSero software tool classifies strains of Salmonella. It identifies serotypes or individual distinct strains using whole genome sequencing (WGS).​

“We recently analyzed 390 Salmonella genomes in about four hours; this normally takes scientists days to do. And, we can now add new genomes to the dataset and rerun the data in just 20 minutes,” ​said den Bakker.​

The National Center for Biotechnology Information Sequence Read Archive database includes genomic information for more than 70,000 genomes.

Purdue researchers​ have applied light and other technologies to areas such as food safety.

Photonics is the science and technology of generating, controlling and detecting photons, which are particles of light.

Yong Chen, a Purdue University professor of physics and astronomy and electrical and computer engineering and director of the Purdue Quantum Center, is leading a team to explore new ways to use photonics science and technologies.

They aim to create photonics-based pathogen sensors for food and fluid samples to bridge the gap between university-scale research and real-world deployment, offering enhanced performance at lower cost.

Challenges with current pathogen sensors are the time to produce results and inaccuracy.