Hello,
Thank you for your query at DoctorSpring.com
I understand your concern.
Yes most forms of meningitis are bacterial in origin, and they are contagious. The vulnerable group are toddlers, under 5 children and teenagers. Most adults will already have some immunity to meningitis since they harbor the bacteria in their throat. In adults the chances of infection from are lower compared to the vulnerable groups i mentioned.
You need to avoid contact as much as possible, because only prolonged close contact can lead to infection. Also sharing items such as razors or toothburshes need to be avoided. If there wasn't much exposure to your co worker, then you should not worry.
Based on what meningitis he has ( Pneumococcal/ H. Influenzae B), appropriate antibiotics can be given prophylactically if the contact was prolonged and the exposure is high. We normally don't advocate the use of antibiotics right away since the chances of resistance get higher. For those who have prolonged contact, Penicillin or Cefotaxime is a good drug as a prophylactic measure.
Feel free to discuss further,
Regards.