In case the other readers did not open the link. The Canadian link by the Niagara Parks Horticulturist ("The Niagara Parks Botanical Gardens is known world-wide for its incredible rose garden. You’ll find over 2,400 roses on display here.") She stated: "Clean and disinfect your pruners between plants if you have noticed any signs of rose virus – mottling and unusual colorations in the leaves." She is in a northern climate. I agree with your fellow Canadian's recommendation that you use separate pruners on infected plants. But, be aware that not all virused roses show symptoms frequently so you are still running some possible risks. I say possible because I am not aware of any research concerning pruning spread in northern climates. I feel that hot weather research may not apply due to the roses having a temperature dependent immune system against the common rose viruses. My article on what is known about the temperature dependence is at: https://sites.google.com/site/temperatureandrosemosaicvirus/home --------------------------------------------------- I mainly discussed PNRSV, but one of the other common rose viruses ApMV is recognized as having a similar temperature dependence: " " It was reported that plant defense mechanisms that specifically target viral RNA (silencing) are more active at high temperatures (Szittya et al., 2003; Chellappan et al., 2005). Therefore, the combination of this factor with the alleged lower viral replication during the hot months of the year may explain the differential virus behaviour throughout the year. " http://www.fupress.net/index.php/pm/article/viewFile/16295/16994

That does not look like RMV at all. My thought was some type of insect damage. RMV is usually very yellow and the leaves stay supple until they drop and not dry brown looking like that. Spray burn can also cause dry brown spots like that. It could also be caused by weather conditions if you've had storms or extremes.

The following was stated earlier in this thread: "I have a couple of roses that do this and they are doing fine. I would ignore it and not read any remark by Henry." H. Kuska comment: It appears that some things have not changed much since the following comment was made. https://groups.google.com/g/rec.gardens.roses/c/VhgwCRP1rO0/m/Wb9k-OoUpRUJ?pli=1 ---------------------------------------------------------------------------------------------- While other things have changed: The following was stated earlier in this thread: "Rose Mosaic Virus is NOT fatal to roses. There are many separate viruses that fall under the RMV umbrella and so far I have never seen any proof that any of them will kill the rose. I know I have many infected roses in my garden and even in my cold climate it hasn't been fatal to them." --------------------------------------------------------------- H.Kuska comment: most references that I have seen say something along the line that the virus may weaken the plant to the extent that those in colder climates often lose their virused roses due to cold injury. I guess we are just talking semantics if we try to say the cold killed the rose not the virus. ----------------------------------------------------------- The following was stated by (apparently) the same author 11 years ago" "seil zone 6b MI I don't replace them either. There are so many that can only be found now with RMV that I'd have a hard time doing it anyway. Besides that in my cold zone they usually will just not come back from a winter when they've weakened sufficiently so I just dig them out then." https://www.houzz.com/discussions/1711311/rose-mosaic-virus-what-to-do

What temperature zone are you in? Roses have an immune system that is more effective against some of the common rose viruses at high temperatures. Without knowing where you live and which actual virus (or viruses) your plant has (plus which strain you have, strong or weak), one cannot predict whether your infection is simply a cosmetic problem or could affect your plants growth and longevity and possible spread to your other roses. This is the most recent paper that I could find (see page 17 about roses in Table 1): https://apsjournals.apsnet.org/doi/pdf/10.1094/PDIS-05-20-1061-FE The affiliations of the authors in the above paper are: Authors and Affiliations M. Fuchs † , School of Integrative Plant Science, Cornell University, Geneva, NY 14456 C. V. Almeyda , Micropropagation and Repository Unit, North Carolina State University, Raleigh, NC 27695 M. Al Rwahnih , Foundation Plant Services, Plant Pathology Department, University of California, Davis, CA 95616 S. S. Atallah , Department of Agricultural and Consumer Economics, University of Illinois, Urbana-Champaign, IL 61820 E. J. Cieniewicz , Plant and Environmental Sciences, Clemson University, Clemson, SC 29634 K. Farrar , Foundation Plant Services, Plant Pathology Department, University of California, Davis, CA 95616 W. R. Foote , Crops and Soil Sciences, North Carolina State University, Raleigh, NC 27695 D. A. Golino , Foundation Plant Services, Plant Pathology Department, University of California, Davis, CA 95616 M. I. Gómez , Charles H. Dyson School of Applied Economics and Management, Cornell University, Ithaca, NY 14853 S. J. Harper , Department of Plant Pathology, Washington State University, Prosser, WA 99350 M. K. Kelly , Department of Agriculture and Markets, Division of Plant Industry, Albany, NY 12205 R. R. Martin , Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331 T. Martinson , School of Integrative Plant Science, Cornell University, Geneva, NY 14456 F. M. Osman , Foundation Plant Services, Plant Pathology Department, University of California, Davis, CA 95616 K. Park , Charles H. Dyson School of Applied Economics and Management, Cornell University, Ithaca, NY 14853 V. Scharlau , Washington Wine Industry Foundation, Cashmere, WA 98815 R. Smith , University of California, Cooperative Extension, Sonoma County, Santa Rosa, CA 95403-2894 I. E. Tzanetakis , Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, AR 72701 G. Vidalakis , Department of Microbiology & Plant Pathology, University of California, Riverside, CA 92521 R. Welliver , The Pennsylvania Department of Agriculture, Bureau of Plant Industry, Harrisburg, PA 17110 ----------------------------------------------------------------------- The following is a more complete discussion of the temperature effect (which applies to some of the rose viruses): https://sites.google.com/site/temperatureandrosemosaicvirus/home