"Those using wooden cutting boards were less than half as likely as average to contract salmonellosis, those using plastic or glass cutting boards were about twice as likely as average to contract it. Cleaning the board regularly after preparing meat made no difference." 
"3 min after contaminating a wooden board 99.9% of bacteria had died, while none of the bacteria died on plastic. Bacterial numbers actually increased on plastic cutting boards held overnight at room temp., but the scientists could not recover any bacteria from wooden boards."
“A remarkably great difference in the survival of the bacteria on the surface was observed between wooden samples and plastic and steel. Oak showed the highest decrease rate, followed by beech and ash. Bacteria survived longest on plastic followed by stainless steel.”
Here is a good page that summarizes a bunch of different studies on this subject. I am in no way sponsored by the mighty and global wooden cutting board industry lobby by the way. commonsensehome.com/wooden-cutting…
Pine wood chips and pallets had better hygienic characteristics than polyethylene chips and plastic pallets in meat processing factories according to study at the Federal Biological Research Centre for Agriculture and Forestry in Braunschweig, Germany. link.springer.com/article/10.100…
"Wood surfaces and many wood compounds have antibacterial properties... the lignin that binds the fibres together has an antibacterial effect. In addition, wood surfaces dry quickly; this dryness puts bacteria at a disadvantage." — Tiina Vainio-Kaila woodproducts.fi/articles/antib…
"When the amounts of bacterial growth on different surfaces were cultured and compared in a laboratory, both e. coli and listeria bacteria gradually died on the wood surface, but survived on the glass plate serving as a control." — Tiina Vainio-Kaila
"After contamination of cutting boards made of nine different hardwoods and plastics with several hygienically relevant gram-negative bacteria, significantly fewer viable bacteria were detected on the wooden boards than on the plastic boards, new or used." researchgate.net/publication/22…
"The porous nature of wood...often generates unfavorable conditions for microorganisms. In addition, wood has the particular characteristic of producing antimicrobial components able to inhibit or limit the growth of pathogenic microorganisms." onlinelibrary.wiley.com/doi/full/10.11…
Do I need to post more of these or do you think the skeptics will get the point? thespruceeats.com/are-wooden-spo…
