By Katia Hetter, CNN
(CNN) — Health officials in the United Kingdom are investigating a cluster of meningococcal infections, including two deaths.
The situation has drawn renewed attention to meningococcal group B, or MenB, an infection that can cause severe illness and has been associated with outbreaks, especially among adolescents and young adults.
To better understand what this means and how people can protect themselves, I spoke with CNN wellness expert Dr. Leana Wen, an emergency physician and clinical associate professor at George Washington University. She previously served as Baltimore’s health commissioner.
CNN: What is meningococcal group B disease, and how serious is it?
Dr. Leana Wen: Meningococcal group B disease is a severe bacterial infection caused by Neisseria meningitidis. It can lead to meningitis, which affects the lining of the brain and spinal cord, or to a bloodstream infection known as septicemia. Sometimes both occur together. Although rare, these are medical emergencies because people can become critically ill within hours.
In the current situation in Kent, as of Thursday, UK health officials reported 15 laboratory-confirmed cases and 12 suspected cases under investigation, bringing the total to 27. Two people have died. Many of the cases have been linked to a nightclub exposure among young people, which helps explain how quickly the cluster emerged.
Even with treatment, invasive meningococcal disease can be very serious. It can be fatal in 8% to 15% of cases, and survivors may experience long-term complications such as hearing loss, neurological damage or limb loss.
CNN: What is known about the UK cases, and how should people interpret the risk?
Wen: This appears to be a localized cluster rather than widespread transmission. What stands out is the speed and concentration of cases over a short period. Public health officials have described it as an unusually rapid cluster and have moved quickly to identify contacts and limit further spread.
At the same time, the overall risk to the public remains low. Meningococcal disease is rare. What is happening here is a reminder that rare but severe infections can still occur, especially in settings where people are in close contact. For Americans and others outside of the UK, these events should be viewed as a prompt for awareness rather than alarm.
CNN: How is MenB spread, and who is most at risk?
Wen: Meningococcal bacteria spread through respiratory and throat secretions. This typically requires close or prolonged contact, such as kissing or sharing drinks, utensils or other items that come into contact with saliva. It is not spread through casual contact.
There are three main ages when risk peaks. The highest rates occur in infants, who are vulnerable to this disease and many others due to limited immunity.
There is also a peak in adolescence and early adulthood. Teenagers and young adults are more likely to carry the