NCIS: Naval Criminal Investigative Service Episode 11.11 Homesick

After several children from Navy and Marine families living in military housing are admitted to the hospital with a sudden unknown infection, NCIS calls upon Carol Wilson (last scene in episode #193) at the Naval Medical Research Center for her help on the case. As an increasing number of children are hospitalized with similar symptoms, the team is alerted to the death of an elderly man who succumbed to the mystery infection. Ducky's autopsy report helps Abby and Carol identify the disease as an aggressive strain of strep pneumonia and they proceed to instruct the hospitals to administer the appropriate antibiotics.The team continues the search for the source of the disease and suspects the perpetrator is an ex-employee at a chemical research facility who was recently fired for stealing toxic mold spores. After the spores are ruled out as the origin of the disease, they discover the administered antibiotics were ineffective and the disease has mutated, causing lesions to develop in the children's throats. They finally trace the disease to a marine captain who recently returned from the Congo and made the rounds as Santa Claus at various military functions. He was a carrier of the Meningococcal-A bacterium while immune to the disease himself. Fortunately, they are able to provide antidotes to every sick child. Meanwhile, Vance struggles with the decision to let his kids meet their estranged grandfather who deserted the family when Jackie was young and Abby tries to alleviate Jimmy's worries about fatherhood.