TB Case at PNBHS
14/06/2010
| TB Case at PNBHS
MidCentral Public Health has confirmed they have been notified about a Tuberculosis (TB) case in a student attending Palmerston North Boys’ High School (PNBHS).
Medical Officer of Health Dr Jill McKenzie said: “This case has been diagnosed early in their illness and is believed to have only been a low infection risk to others. Testing of contacts at highest risk of infection has so far showed no evidence of further disease spread. The case has commenced treatment and is no longer considered to be infectious.”
Public Health staff are working with PNBHS staff to ensure information about TB is provided to the students and their families. It is unlikely that there will be a need for testing of students beyond the closest contacts of the case.
Public Health staff follow a systematic process for testing contacts of TB cases beginning with those at highest risk of infection. If these high risk contacts show no evidence of TB infection then this indicates a case is of low infectivity and there is no need to do further testing.
“At this stage it is felt most likely that the source of the TB disease was from progression of TB infection. The student was infected with TB as a result of exposure to a previous case attending PNBHS,” Dr McKenzie said.
A highly infectious case diagnosed in 2006 led to the testing of around 1800 people both within and outside of the school, and treatment of 235 people for TB infection and 15 people for TB disease.
TB infection is a non-infectious and symptom free condition where the immune system contains the bacteria in a harmless form. A small percentage of people with TB infection will progress to infectious TB Disease (10-15% chance over a lifetime without treatment, <5% with treatment). Only TB disease affecting the lungs is considered infectious to others.
TB disease in the lungs causes symptoms such as a persistent cough that doesn’t get better with standard antibiotic treatment, weight loss, and sweats especially at night. Anyone with these symptoms should be assessed by a doctor. The TB bacteria is very slow growing so it takes several weeks or months before a person may develop symptoms from TB disease.
TB disease is uncommon in New Zealand. The average number of cases per year in New Zealand for the last five years has been around 320. In the MidCentral region we see around seven cases a year. Most cases are associated with living in countries where TB is more common, or in close contacts of known infectious cases.
TB is a treatable disease using a combination of specialised antibiotics. If TB disease is recognised early and treatment started there is a low chance of infection being passed onto others. The highest risk for becoming infected with TB is for close contacts such as those who live in the same household. It is uncommon for TB to be spread to people without frequent and very close contact with the infectious person.
• More information about TB can be found at http://www.arphs.govt.nz/notifiable/downloads/TB.pdf . If you are concerned about exposure to TB you can ring the Public Health Unit (06) 350-9110 for further information.
Contact: Communications Unit (06) 350-8945