Tomato brown rugose fruit virus: Hygiene best practice and biosecurity
Hygiene best practice procedures should be implemented as standard in any horticultural business. They should be followed as a precautionary measure to reduce the likelihood of infection with tomato brown rugose fruit virus (ToBRFV) and minimise the impact of an outbreak.
Key hygiene measures
As the virus is primarily transmitted via contact, a suite of preventative measures termed ‘hygiene best practice’ should be followed, to minimise the chances of the virus entering and spreading within a crop.
These precautions should be applied routinely. This list is not exhaustive but gives recommended measures to minimise the risk of spread of contact-transmitted pathogens including other viruses and viroids.
- Access should be limited to people working in the specific crop/glasshouse
- Limiting access helps to minimise the risk of inadvertent introduction and spread around the glasshouse production facility via human activity
- As a standard, there should be no direct travel between packhouses and glasshouses
- Clothing must be changed/washed between the two locations if entering on different days
If infected produce goes through a packing facility, both machinery, equipment, and workers can be contaminated. If these workers or equipment are then moved into a production facility, this can spread the virus into a previously healthy crop.
Staff should be trained in basic symptom recognition and hygiene measures to contain outbreaks of pathogens when they occur, including best practice for plant handling, etc.
Ideally, staff should not be moving between production facilities and should never move between packing and production facilities.
Growers, employees and visitors eating fruit of tomato and pepper, which may be contaminated, could inadvertently pass on the virus.
Although washing your hands for 30 seconds does not kill the virus, nurseries should continue to implement their standard handwashing procedures, to prevent the spread of other diseases, and ensure gloves are changed often.
Disposable gloves should be used and changed regularly. The virus will remain active on hands and gloves for at least two hours.
Workers should use disposable clothing, such as a disposable oversuit and shoe covers, to minimise introduction and spread of the pathogen. These should be:
- Put on when entering a glasshouse
- Disposed of on leaving the glasshouse
- Not reused
If this is not feasible for full-time staff, they should be issued clothing to wear only in the glasshouse, which is then regularly laundered at high temperature (each day).
Growers could use clothing in different colours to denote workers from different parts of the site, to prevent cross-contamination, or consider assigning a clothing colour to a day, to help ensure a clear rotation so that clothes are not reworn from the previous day.
- Equipment and tools that come into contact with an infected plant can act as a source of virus for onward transmission
- Equipment such as picking carts, sprayers, and hand tools (e.g. pruning knives) should all be cleaned and disinfected routinely
- Tools should ideally be disinfected during pruning activities between individual plants, but at the very least between rows
- Equipment should be cleaned and disinfected at least between crops
- The virus on plastic trays can be destroyed by heat treatment (e.g. steam sterilisation) for five minutes at 90°C
Risk assess your business
It is vital to carry out an assessment of your business and the hygiene and biosecurity protocols in place at each stage of production. The tomato brown rugose virus process flow risk assessment has been produced to help you identify the risk points in your business and production cycle, and help you instigate measures to mitigate for ToBRFV.
How is ToBRFV being managed in Europe and Israel?
At the end of 2019, plant pathologist Dave Kaye (RSK-ADAS) completed a fact-finding trip to the Netherlands, Germany and Israel to determine how growers, researchers and related industries in those countries are tackling the issue of ToBRFV. Visit the fact-finding trip summary page to read the best practice recommendations for management of ToBRFV in other countries.