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European Antibiotic Awareness Day is taking place on 18 November 2021. For this occasion, ANSES is publishing the results of several monitoring programmes that it carries out to prevent the emergence and spread of antibiotic-resistant bacteria in farm and domestic animals in France. Below is a review of some key findings with Jean-Yves Madec, Scientific Director for antimicrobial resistance and Head of the French surveillance network for antimicrobial resistance in pathogenic bacteria of animal origin (RESAPATH), Gérard Moulin, Deputy Director of the French Agency for Veterinary Medicinal Products (ANMV), and Agnès Perrin-Guyomard, Deputy Head of the National Reference Laboratory for antimicrobial resistance.

Mosquito traps are increasingly used in public spaces as a means to prevent mosquito bites and to control mosquito-borne diseases. However, the studies currently available are not sufficient to demonstrate the short-term effectiveness of these traps in preventing the spread of mosquito-borne diseases. ANSES is therefore encouraging their use primarily as a preventive measure (in the medium and long term) to reduce high mosquito density as part of an integrated control strategy. ANSES also points out that the marketing and use of these traps must comply with regulations. In recent decades, a number of mosquito-borne diseases – such as dengue, chikungunya and Zika – have spread outside tropical regions. The use of mosquito traps as a complement or alternative to other techniques for controlling the spread of viruses, is a relatively recent idea. In France, the operators responsible for limiting the spread of mosquitoes are appointed by the Regional Health Agencies (ARSs). Some 15 operators currently exist, but they do not all use mosquito traps in the same way. ANSES conducted a literature review to assess the effectiveness of the mosquito traps used by operators as part of vector control. Several ways to attract female mosquitoes Two main types of trap are used to catch female mosquitoes, which are the only ones able to bite and to transmit pathogens. The first type of trap simulates an egg-laying site. A water-filled container uses a variety of means, including insecticide and glue strips, to trap the females when they come to lay their eggs. The second type of trap attracts mosquitoes by simulating the breathing of a living being through the diffusion of carbon dioxide (CO2) and/or the use of visual or olfactory attractants (for example, lactic acid to simulate human body odour). A control method to be used alongside other techniques “ We have a body of evidence showing that both types of trap can have a preventive effect in reducing the mosquito population in the medium and long term (over several weeks, months, or even years), providing that they are well maintained and used in sufficient numbers ,” says Johanna Fite, head of the "Vectors" unit at ANSES. “ However, they are not a magic solution. Traps are most effective when used in conjunction with other control methods , particularly the elimination of breeding sites. " No studies concerning the impact of traps on the spread of disease Some operators place traps when cases of vector-borne disease are identified. Traps are set up for a period of three to six weeks around the homes of infected people. The expert appraisal conducted by ANSES identified no data shedding light on the effectiveness of traps in quickly containing the spreading of disease when the viruses are already in circulation. The Agency therefore recommends that research be carried out in order to collect data on this question and to determine the best conditions for the deployment of these traps, based on different epidemiological scenarios, including an isolated case, an outbreak and an epidemic. Pending these additional data, mosquito traps should be used only as a preventive measure, or in cases where it is not possible to use an insecticide, for example when the area to be treated is inaccessible or close to a waterway. A reminder needed of the regulations CO2, lactic acid and other substances used to attract female mosquitoes are biocidal substances. Traps using these substances must therefore comply with the regulations on biocides . They also require marketing authorisation (MA). To date, no applications for marketing authorisation have been filed in France for mosquito traps using CO2. Under the terms of a transitional regime, the marketing of traps using CO2 produced through combustion is authorised until July 2022. After this date, it will no longer be possible to sell traps without a marketing authorisation in France. Applications for marketing authorisation must include documentary proof of the effectiveness and safety of these traps. Finally, devices will not be able to make claims such as "zero nuisance" or "mosquito-free home" without proof.

Certain drinking water pipes are made of asbestos cement. Under some circumstances, therefore, asbestos fibres can be found in drinking water. ANSES has conducted an initial review of the scientific literature to characterise the hazards associated with asbestos ingestion. Before it was banned in France in 1997, when respiratory exposure was found to be hazardous to humans, asbestos was used in a variety of sectors, particularly in construction. In fact, 4% of the French public drinking water supply network still consists of asbestos cement. " The risk of asbestos fibres being released into the water supply remains low when the pipes have been installed in stable non-aggressive soil, and when the water carried by these pipes contains calcium, because the build-up of scale protects the pipe . However, risks from the presence of asbestos in drinking water cannot be ruled out in the case of badly deteriorated pipes ," say scientists from ANSES's Water Risk Assessment Unit. As people are mainly exposed to asbestos by air, studies on the health risks of asbestos have, until now, mainly focused on this source of exposure. The last baseline analysis conducted by the International Agency for Research on Cancer (IARC) in 2012 on the links between asbestos and the occurrence of cancer did not explicitly address the hazards associated with ingestion. The expert appraisal was prompted by two alarmist studies, which nevertheless had limitations Two studies by an Italian research team, published in 2016 and 2017, had concluded that the health risks associated with asbestos ingestion, mainly through the daily consumption of drinking water, may be underestimated. In its scientific and technical analysis note published in 2017, ANSES observed that these two studies were not sufficiently robust: they had not assessed the quality of the publications on which they had based their conclusions and had not taken into account all the scientific publications available on the subject. The Agency was therefore asked to characterise the hazards of asbestos by ingestion, by conducting a systematic review of the scientific literature . Not enough evidence to rule on a causal relationship In order to study the health hazards of asbestos ingestion, in particular concerning the development of digestive cancers (oesophagus, stomach, small intestine, liver, etc.), the Agency conducted a comprehensive review of current knowledge on this subject. Of the 4409 human and 1107 animal studies on the effects of asbestos, the experts identified 17 studies examining asbestos ingestion in the general population, 19 examining asbestos ingestion in animals and 41 examining occupational exposure to asbestos. The working group conducted a standardised assessment of these studies to determine the levels of evidence that could be used to characterise the plausibility of a link between asbestos exposure and the occurrence of digestive cancers. This assessment led the experts to conclude that the levels of evidence were "inadequate", i.e. the data published to date cannot be used to rule on the possibility or absence of an association between asbestos ingestion and digestive cancers. " Most of the existing studies are old or have methodological limitations that mean they are unable to demonstrate a causal link between asbestos ingestion and the occurrence of these cancers ," explain the experts of the working group. Signals for some cancers but no certainty However, the existence of signals suggesting the possibility of an association between asbestos ingestion and three specific digestive cancers was highlighted. These are cancers of the oesophagus, stomach and colon. This possibility is supported by epidemiological studies conducted in occupational settings that report more cases of these cancers in workers exposed to asbestos than in the general population. This is because a fraction of the asbestos inhaled by workers can be swallowed and pass directly into the digestive tract. However, the data do not enable a reliable estimate of the extent of this fraction compared with that reaching these organs via the respiratory route, through the lungs and the bloodstream, and mean that these results cannot be extrapolated to exposure by ingestion. Surveillance campaigns recommended Given the past use of asbestos in certain pipes, the Agency recommends conducting targeted campaigns to detect the presence of possible asbestos fibres in drinking water liable to contain them. These data could then be used for future studies or epidemiological surveillance work. The Agency also recommends monitoring the condition of asbestos cement pipes to ensure that they are renovated or replaced in the event of damage.