Ebola and Polio alerted as 'Public Health Emergencies of International Concern'
In 2019, there were two ongoing ‘Public Health Emergencies of International Concern’ (PHEICs) :
- Ebola (2019–present)
- Polio (2014–present)
Neither cases of Polio nor Ebola have been reported in New Zealand during these PHEIC periods.
Mosquito-borne disease notification counts have increased since 2001, particularly from 2014
Five mosquito-borne diseases were detected in New Zealand in 2017 :
- Four mosquito-borne viruses: Chikungunya, Dengue Fever, Ross River Virus and Zika
- One mosquito-borne parasitic disease: Malaria
Mosquito-borne disease notification counts have increased since 2001, particularly from 2014 (Figure 1). This trend was driven by an increase in the number of Dengue cases and the emergence of Zika and Chikungunya since 2014.
Figure 1: Number of case notifications of mosquito-borne diseases in New Zealand, 2001-2017
Differences in the characteristics of people who had priority border health diseases
Among people diagnosed with mosquito-borne diseases in New Zealand, there were:
1. Differences in overseas travel
The Pacific was the most frequently visited region among people returning with Dengue, Zika and Chikungunya from 2016–17. Asia was the most frequently visited region for people returning with Malaria .
Almost all people diagnosed with mosquito-borne diseases in New Zealand, in 2016 and 2017, were thought to have acquired these diseases while travelling overseas. The exception to this was one locally acquired case of Zika in 2016, although this was most likely sexually transmitted.
2. Differences in age:
Over the five-year period, 2013–17, mosquito-borne viral disease notification rates were higher for youth, adults and middle-aged adults compared to the childhood and older adults age groups (Figure 2).
Over the same period, rates of Malaria were higher in youth and adults compared to childhood and older adults (Figure 2).
Figure 2: Incident rate of Malaria and mosquito-borne viral diseases 2013–17, by age
Data Source: ESR 2019.
3. Differences in ethnicity:
From 2014–17, the Pacific ethnic group had the highest rates of mosquito-borne disease. In 2017, the rate of mosquito-borne disease in Pacific people was 21.6 per 100,000, six times that of the Other ethnic group .
4. Socio-economic differences in rates of mosquito-borne disease:
For the 2016–17 period, there were differences in the notification rate of mosquito-borne disease by level of socio-economic deprivation. More deprived areas had higher rates of mosquito-borne disease than less deprived areas. Notification rates were 8.4 cases of mosquito-borne disease per 100,000 people living in the most deprived areas (NZDep2013 quintile 5) and 5.4 cases per 100,000 in the least deprived areas (NZDep2013 quintile 1) [3,4].
5. Differences by region:
Over the period 2016–17, people living in the Auckland DHB and Counties Manukau DHB had a higher rate of mosquito-borne disease compared to the New Zealand average (Figure 6). 220 of 578 cases (38%) were in Auckland and Counties Manukau DHBs .
1. World Health Organization. Global Alert Response (GAR). [Accessed November 2019]. Available from: http://www.who.int/csr/resources/publications/en/
2. Institute of Environmental Science and Research Limited (ESR). 2016. Notifiable Diseases in New Zealand: Annual Report 2016. Porirua: Institute of Environmental Science and Research Limited.
3. Institute of Environmental Science and Research Limited (ESR). Notifiable diseases EpiSurv data extraction. Porirua: Institute of Environmental Science and Research Limited. [2019 personal communication with ESR Senior Analysts]
4. Atkinson J, Salmond C and Crampton P. 2014. NZDep2013 Index of Deprivation. Wellington: University of Otago