Consumer Reports released their testing results of frozen produce. Nothing special to report regarding pathogens or nutrient quality. Their testing did not yield any pathogenic bacteria. Which we would generally expect. From a nutrient perspective, they found that frozen is generally comparable to fresh.
That being said, it is always important to follow proper handling and preparation procedures. From time to time, we can encounter contamination issues, such as with Listeria. While the study did not look for viruses or parasites, and although a low risk, these too have been found. https://www.cdc.gov/parasites/cyclosporiasis/outbreaks/foodborneoutbreaks.html
https://www.consumerreports.org/food-safety/are-frozen-fruits-and-vegetables-healthy-and-safe-a1002196402/
Are Frozen Fruits and Vegetables Healthy and Safe?CR tested more than 300 samples of frozen produce for bacteria that commonly cause foodborne illness
"For our tests, we looked for E. coli, listeria, and salmonella, types of bacteria that commonly cause foodborne illness, in eight frozen categories—avocado, berries, corn, mangoes, peaches, pineapple, spinach, and smoothie mixes. In total, we included 369 items from big brands, private label, and store brands, including 365 by Whole Foods, Blendtopia, Birds Eye, Campoverde, Dole, Great Value, O Organics, and Trader Joe’s."