Tomato brown rugose fruit virus: survival and disinfection

Read the findings from this research project (PE 033) and explore how long it survives on different surfaces. Find out which disinfectants are most likely to reduce the risk of infection and control the spread of the virus.

ToBRFV can cause infected tomato and pepper fruit to become discoloured and misshapen. It can easily spread to all plants in a crop via mechanical transmission.

It has been confirmed that this virus:

• Can survive for long periods on a range of surfaces
• Is environmentally stable
• Is difficult to eradicate using existing disinfection techniques

The aim of this research project is to gather data in support of current hygiene best practice advice, to ensure the advice is effective against ToBRFV. This includes confirming the survivability of the virus on skin and common glasshouse surfaces including tools and picking crates, as well as investigating the efficacy of a range of disinfectants in denaturing the virus.

Skin and gloves

• The virus can last for at least two hours on skin and nitrile gloves, and still cause infection

Glasshouse surface

• ToBRFV survived for at least six months on some surfaces, including hard plastic, polythene and glass
• ToBRFV survived for at least one month on aluminium and at least three months on stainless steel
• ToBRFV can survive on concrete up to three months, but this looks variable as in some cases the virus did not survive two weeks

In general, handwashing is not effective at removing ToBRFV with, in most instances, at least a one-minute wash required to remove the virus. For example, a one-minute wash with Nzym Rugo was effective. However, this is not practical on a busy production site.

We recommend washing hands regularly, but, more importantly, changing gloves on a regular basis.

The virus survived after one minute of treatment with a range of disinfectants, all applied at recommended rates (please see the latest summary report below for the rates used), on all glasshouse surfaces tested.

Results from testing the efficacy of disinfectants at 1-hour contact times, suggest:

• Virkon S and Huwa San are effective against ToBRFV at 1-hour contact time on all surfaces except concrete
• Menno Florades is mainly effective against ToBRFV at 1-hour contact time on all surfaces except concrete
• Sodium hypochlorite is partially effective against ToBRFV on polythene and glass, and is effective on other surfaces
• Jet 5 and TSOP do not appear to be effective on most surfaces

These results suggest concrete could be a particularly difficult surface to disinfect, once contaminated with ToBRFV infected leaf sap.

Table 1. Disinfectants tested against ToBRFV and rates of use 

• Soaking trays in hot water for five minutes at 90^oC can eliminate the virus
• Soaking trays in hot water for five minutes at 70^oC was insufficient to kill the virus. However, a five-minute soak at 70^oC followed by spraying with Virkon, was effective

Update:

• Follow-up trials in early 2021 have confirmed that 90^oC is the thermal inactivation point for ToBRFV, and that it is the action of heat rather than a washing process that is required to ensure virus kill.

This information is based on our research project on the survival and disinfection of the virus, which is being led by Adrian Fox at Fera Science Ltd. We’ll continue to update the industry with further information as and when results are available.

This project has been conducted for research and development purposes. The research evaluated a range of products used for general disinfection purposes (hand sanitisation; cleansing and disinfection of glasshouse surfaces). No endorsement or recommendation of named products is intended nor is any criticism implied of alternative, untested products.

The products named in this report are not necessarily authorised as biocides across all UK cropping situations and mention of a product does not constitute a recommendation for its use against specific plant pathogens. Biocidal and plant protection products must only be used in accordance with the authorised conditions of use.

Any product marketed for use specifically against Tomato Brown Rugose Fruit Virus (ToBRFV) or any other plant pest/disease would require an authorisation under the Plant Protection Products Regulations/Regulation (EC) 1107/2009 before they are placed on the market for this use.

Regular changes occur in the authorisation status of biocides and plant protection products. For the most up to date information, please check with your professional supplier, BASIS registered adviser or the Chemical Regulation Division (CRD) of HSE. (https://www.hse.gov.uk/crd/).

While the Agriculture and Horticulture Development Board seeks to ensure that the information outlined on this page and in the project report is accurate at the time of publishing, no warranty is given in respect thereof and, to the maximum extent permitted by law the Agriculture and Horticulture Development Board accepts no liability for loss, damage or injury howsoever caused (including that caused by negligence) or suffered directly or indirectly in relation to information and opinions contained in or omitted from this information.