Q: My grandson had an ear infection a week or two ago which caused a lot of discharge. Now my daughter and I have developed impetigo and we are all on antibiotics. What is going on?
A: It is likely that the original infection in your grandson was caused by bacteria in the Staphylococcus or Streptococcus families of bacteria.
Some species can be very infectious and pass quickly amongst close family members, particularly those in closest contact with the original case. It is passed on usually by direct close physical contact.
Although the same bacteria are responsible it can cause different patterns of infection in different people.
If the contact patients are healthy then usually the infection will be skin based, for example impetigo (an open area of infected skin), skin boils and abscesses or infected minor wounds.
In those whose resistance to infection is poor, the situation can be more serious with invasive infections of the chest and other body systems.
Once an infection like this has affected several family members it is important that all of those who have had close contact with the index case (your grandson in this case) are treated simultaneously, even if they are not currently showing any signs of infection.
Usually this would include all close family members and a course of oral antibiotics together with a focus on hygiene to avoid further spread should quickly confine the infection.
Hygiene would involve careful hand washing and flannels and towel use confined to one individual.
Your GP can advise who needs to be treated but if the situation is complex or spreading quickly then there are specialist infection control nurses who will take on the control of the outbreak.
In a confined family setting outbreaks are usually easy to control but in residential care or boarding schools, specialised help is often necessary.