One aspect of Karma is that it is contagious nature. Say you have bad Karma when the fruit ripens in many cases some being near you should harm you and be instrumental in the karma giving its fruit. Then the being who is instrumental accumulated bad Karma.

Hence if people around you do negative karma, then there is a possibility that there will be a negative vibe with all associated people due to the complex interactions.

Hence it is best to encourage your circle to be as positive as then can and avoid negativities but the best extent you can. This give two benefits:

1. Good Karma for you for doing a good deed
2. Collective good Karma (or lack of bad Karma) means you would accumulate more positivity through the process

One aspect of Karma is that it is contagious nature and cumulative in nature. Say you have bad Karma; when the fruit ripens, in many cases some being near you should harm you and be instrumental in the karma giving its fruit. Then the being who is instrumental accumulated bad Karma. In the future some one else (in most cases) must be instrumental in giving a means for the karma to manifest.

Also due to the liking (or the lack of it) most people tend to be born together in Samsara with a higher degree of probability.

Hence if people around you do negative karma, then there is a possibility that there will be a negative vibe with all associated people due to the complex interactions.

Hence it is best to encourage your circle to be as positive as then can and avoid negativities but the best extent you can. This give two benefits:

1. Good Karma for you for doing a good deed
2. Collective good Karma (or lack of bad Karma) means you would accumulate more positivity through the process

Also being collectively good or doing good deeds as a group has better results than just doing as an individual.