Viruses and antibiotic-resistant bacteria: Dangerous pathogens in foodstuffs
Experts from the World Health Organization (WHO) estimate that around two million people worldwide die each year from infections caused by contaminated food and unclean drinking water. In Germany, too, germs lurk in many foods. Some of them can cause fatal diseases.
Microbial risks in food
“Egg recalls due to salmonella”, “Noroviruses detected in frozen raspberries”, “Hepatitis E infections caused by pork”, “Antibiotic-resistant germs in barbecue meat”: Such and similar headlines have been appearing almost weekly in the media for years. But how dangerous are such germs? Experts are now looking into the microbial risks in food.
According to the Federal Institute for Risk Assessment (BfR), pathogenic microorganisms are among the most frequent causes of food-borne diseases. Every year, they cause more than 100,000 diseases in Germany – some of them fatal.
Against this background, two BfR symposia will deal with microbial risks in food in November 2018: “Food-associated viruses” on 7 November and “Antibiotic resistance in the food chain” on 8/9 November.
“Microbial risks have become a public concern”, said BfR President Professor Dr. Dr. Andreas Hensel in a press release.
“Our current representative population survey, the BfR consumer monitor, shows that 97% of those questioned heard of salmonella in food, or 89% of antibiotic resistance,” explains the expert.
The majority of respondents said that “they are concerned about these issues. Everyone is able to minimise the personal health risk through appropriate kitchen hygiene”.
More food-borne diseases
According to the BfR, the number of food-borne diseases caused by viruses is steadily increasing. For example, hepatitis E is increasingly transmitted via food from infected pigs and wild animals.
Cases of food-borne infections with Noro and Hepatitis A viruses are also on the rise. A European Reference Laboratory for Foodborne Viruses has been established to address the growing importance of these viruses.
Although detection methods for viruses in food have improved significantly in recent years, there is still a great need for research on how these pathogens are transmitted and what measures can be taken to prevent their spread.
The use of antibiotics in animal husbandry is declining
The use of antibiotics in animal husbandry has declined sharply in Germany in recent years. Since 2011, the quantities of antimicrobial veterinary drugs that are supplied to veterinarians have been recorded in Germany.
Since then, these quantities have declined continuously by 57 percent from 1,706 tons in 2011 to around 733 tons in 2017, with a simultaneous increase in meat production.
The therapy frequency with antibiotics is also decreasing for farm animals in Germany, as shown by the BfR’s VetCAb (Veterinary Consumption of Antibiotics) research project.
During the same period, the antibiotic resistance of some bacteria in the food chain decreased.
Poultry for fattening as a source of resistant germs
A study covering the period from 2009 to 2016 shows that the proportion of resistant germs against the majority of antibiotics tested in the study has decreased significantly in naturally occurring E. coli in broilers and turkeys.
In particular, drug classes that are used in large quantities or frequently in livestock show a declining trend in both consumption quantities and resistance rates of E. coli.
However, the study also shows that high resistance rates still exist in both fattening poultry chains, so that they can continue to be of considerable importance as sources of resistant germs and their resistance genes in humans.
There is no all-clear for the antibiotic group of fluoroquinolones. Resistance to these has increased in some bacterial species in recent years.
For them, there was also no clear downward trend in the frequency of therapy. Scientists therefore recommend that this trend be closely observed in the future.
Resistance to reserve active substances
Resistance to so-called reserve active substances is a particular challenge for the health care system. These are used in human medicine when the efficacy of other antibiotics has already been ruled out.
The polypeptide antibiotic colistin is an important representative of the range of reserve active substances. Due to the increase in resistance to other substances, the