By Inger Morthorst Møller, on behalf of DanBred.
In previous articles, we have reviewed how we avoid getting unwanted infection into the herd, but it is also obvious that we cannot keep a farm completely sealed. Therefore, thorough and clear rules for farm staff and visitors to the herd must be introduced, complied with, and controlled.
In many farms, it is standard practice that the visitors sign a visitor logbook, in which their last visited herd is noted, the date, and possibly known diseases/SPF-status in the herd. In that way, it might be easier to explain a new infection or at least react to one quickly, should it occur.
To avoid zoonotic diseases in the herd, it will be relevant to ask visitors, before the visit, if he or she has had respiratory symptoms in the last 14 days. Influenza is thought of as a common infection between pigs and humans. The visitor logbook must also help to comply with quarantine rules between herds and areas/countries with infectious diseases.
Personal items on the farm
All-access to the farm must be through a well-appointed changing room, and all personnel items must be left here. If anyone needs to bring equipment or mobile phones, this must not have been brought into another herd and should be disinfected with alcohol and irradiated with UV light. After just a few minutes of irradiation, the DNA in viruses or bacteria is destroyed.
Food from animal origin must not be brought to the farm – in order to avoid diseases spread by food.
It is recommended that personnel from countries with ASF in the wild boar and/or domestic pig population do not bring food from their home countries, including their homes near the farm. Remember that only one mistake can make a disaster for the whole pig industry.
Design of changing room
When entering the farm, it is essential that outdoor clothing is placed with no contact with the farm clothing. This is done both to prevent unwanted pathogens from entering the herd, but also to prevent dust from being dragged from the herd to the surroundings.
The greatest protection against infection is obtained by taking a shower before and after a visit.
Still, it may be sufficient with thorough handwashing followed by paper towels and disinfection with hand sanitizer. Paper towels minimize the risk of spreading pathogens from one person to another. To ensure the right behavior, it is recommended to divide the changing area into an outer zone, which is the area at the entrance, and the inner zone for stable clothing. The outer and inner zones should be separated by the shower or an elevated floor with a wooden or plastic grid.
The design and rules on the specific farm depend on the individual’s willingness to take risks. Still, if the stable is large with unique breeding animals, it is recommended to have biosecurity of very high quality.
Infection between animals and humans – should you WEAR A face mask in the barn?
Zoonoses are diseases that can be transmitted between animals and humans. The classic example is influenza, which is introduced to a herd via employees or visitors who are ill with influenza.
Other agents that have had massive media coverage are Methicillin-Resistant Staphylococcus Aureus (MRSA). Staphylococci are ubiquitous bacteria, usually in the nasal mucosa or on the skin surface, but the problem arises if it enters the bloodstream. Blood poisoning can be difficult to treat but even more complicated if the bacteria are resistant to common antibiotics. Dust from the farm may contain MRSA.
It is therefore important to avoid bringing dust from the farm to the rest of the population.
Research of people who have stayed briefly in an MRSA-positive herd showed that wearing a face mask during the visit significantly reduces the risk of carrying the bacteria out of the barn. It is therefore relevant to have face masks available for visitors. Still, due to working environment conditions, it is not permitted for personnel to use certain masks during an entire working day, as fluid can accumulate in the lungs.
Finally, it is important to point out that a high biosecurity level depends on everyone’s behavior. All staff and visitors are responsible for complying with the guidelines- it must be a high priority for everyone to understand the importance of high biosecurity and the consequences of careless behavior.