Definition: In this task you will be given a question and a passage. You need to determine if the answer to the question is contained in the passage. If the answer can be found in the passage you should output 'True'. If the answer cannot be found in the passage you should output 'False'.
Input: Passage: 'The blood-brain barrier may become leaky in select neurological diseases, such as amyotrophic lateral sclerosis, epilepsy, brain trauma and edema, and in systemic diseases, such as liver failure. The blood -- brain barrier becomes more permeable during inflammation, allowing antibiotics and phagocytes to move across the BBB. However, this also allows bacteria and viruses to infiltrate the blood-brain barrier. Examples of pathogens that can traverse the blood-brain barrier include toxoplasma gondii which causes toxoplasmosis, spirochetes like Borrelia (Lyme disease), Group B streptococci which causes meningitis in newborns, and Treponema pallidum which causes syphilis. Some of these harmful bacteria gain access by releasing cytotoxins like pneumolysin which have a direct toxic effect on brain microvascular endothelium and tight junctions.'. Question: 'how do viruses cross the blood brain barrier'.

True