Number of whooping cough (pertussis) case notifications

Number of pertussis notifications (confirmed, probable and suspect) by age and vaccination status, 1 January 2017 to 31 May 2018

Number of pertussis notifications (confirmed, probable and suspect) by age and vaccination status, 1 January 2017 to 31 May 2018
Age group [1] One dose [2] Two doses [2] Three doses [2] Four doses [2] Five doses [2] Vaccinated – no dose information [3] Not vaccinated [4] Unknown [5] Total
<6 weeks 0 0 0 0 0 0 23 0 23
6 weeks–2 months 35 1 0 0 0 1 25 0 62
3–4 months 14 24 1 0 0 0 12 2 53
5 months–3 years 7 12 243 10 1 21 122 22 438
4–10 years 8 7 44 361 26 59 205 32 742
11–15 years 13 4 15 78 88 40 67 46 351
16+ years 78 6 15 38 75 238 396 1208 2054
Total 155 54 318 487 190 359 850 1310 3723

Notes:

  1. Age groups: Groups relate to the National Immunisation Schedule. Children aged <6 weeks are not eligible for immunisation.
  2. Number of pertussis vaccine doses reported for cases who were recorded as being immunised in EpiSurv.
  3. Vaccinated but no dose information: Recorded as being immunised however no vaccination dose information was recorded in EpiSurv.
  4. Not vaccinated: A person who is recorded in EpiSurv as being not vaccinated.
  5. Unknown: Cases which had no immunisation status recorded or status is recorded as unknown in EpiSurv. Immunisation data is not a priority field for completion in regions that have moved to a ‘Manage it’ phase once an outbreak is established, and hence many cases will have immunisation status recorded as unknown.

Note: Vaccination status has been extracted from EpiSurv. Health professionals may use a range of sources to update vaccination status including the National Immunisation Register, parental recall and Well Child book records.

About this data

This report is based on information recorded on EpiSurv by public health service staff as at 19 June 2018. Changes made to EpiSurv data after this date will not be reflected in this extracted information. The results presented may be further updated and should be regarded as provisional. Cases still under investigation are not included in this report.

The immunisation status was unknown for 35% (1310 of the 3723) of cases reported in EpiSurv. Immunisation data is not a priority field for completion during and established outbreak. A national whopping cough outbreak was declared in November 2017.

In populations where immunisation coverage is high, a greater proportion of the population is protected because immunisation reduces the occurrence and severity of disease. In this situation a higher proportion of those who develop disease are likely to be immunised. This is expected due to the vaccine being 81–85% effective. See the Pertussis chapter of the Immunisation Handbook for more information.


Find out more from the Ministry

  • Vaccine effectiveness – information on why some people who have been vaccinated still catch a disease
Back to top