Monthly Notifiable Disease Surveillance Report - Nov 2013

Chikungunya fever: One probable case of Chikungunya fever was notified in November 2013. The case was a female in the 40-49 years age group from Bay of Plenty DHB and was in Indonesia during the incubation period.

Cryptosporidiosis: 86 cases of cryptosporidiosis were notified in November 2013 compared to 96 cases notified during the same month of the previous year (Figure 1). The cases ranged in age from 10 months to 75 years, with the highest number of cases in the 1-4 years age group (30 cases) followed by those in the 30-39 years (13 cases), and 5-9 years and 20-29 years (10 cases each) age groups. The highest numbers of cases were reported from Canterbury (24 cases), and Waitemata and Southern (10 cases each) DHBs. Among the cases where risk factor information was recorded, 62.2% (23/37) had contact with farm animals, 37.5% (12/32) had consumed untreated water, 32.3% (10/31) had consumed food from a food premises and 31.3% (10/32) had contact with faecal matter. Five finalised Cryptosporidium outbreaks were reported in November (13 cases).

Dengue fever: 11 cases of dengue fever were notified in November 2013 compared to four cases notified during the same month of the previous year. All of the cases had travelled overseas during the incubation period except for one case where overseas information is not yet available. The countries visited were India (4 cases), Indonesia (2 cases), and Eritrea, Malaysia, Myanmar, Papua New Guinea, Philippines and Thailand (1 case each). Some cases visited more than one country.

Hepatitis NOS: One case of hepatitis NOS was notified in November 2013, the case has since been found to not meet case criteria after further investigation.

Hydatid disease: One confirmed case of hydatid disease was notified in November 2013. The case was a female in the 50-59 years age group from Nelson Marlborough DHB and was in Romania during the incubation period. Echinococcus granulosus is endemic in Romania.

Leprosy: Five cases of leprosy were notified in November 2013. The cases ranged in age from 3 to 29 years and occurred in the following age groups: 10-14 years (2 cases) and 1-4 years, 5-9 years, and 20-29 years (1 case each) age groups. The cases were from the following DHBs: MidCentral (3 cases), and Waitemata and Hutt Valley (1 case each). The clinical form of leprosy was recorded as tuberculoid (4 cases) and borderline (1 case).  Four cases had contact with a laboratory confirmed case (4 cases). Three cases travelled overseas to Kiribati (2 cases) or Timor-Leste (1 case). Some cases had more than one risk factor recorded. Two finalised Mycobacterium leprae outbreaks were reported in November 2013 (six cases).

Leptospirosis: 13 cases of leptospirosis were notified in November 2013 (8 confirmed, 1 probable, 4 under investigation) compared to six cases notified in the same month of the previous year. The following section relates to the eight confirmed cases only. These cases were reported from Hawke’s Bay (3 cases), MidCentral (2 cases), and Taranaki, Wairarapa and South Canterbury (1 case each) DHBs. High risk occupations were recorded for eight cases: meat workers or butchers (4 cases), farmers or farm workers (3 cases), and possum trapper (1). Leptospira species and serovars were recorded for six cases: Leptospira borgpetersenii sv Hardjo (4 cases), and L. borgpetersenii sv Ballum and L. interrogans sv Pomona (1 case each).

Ross River virus infection: Two cases of Ross River virus infection were notified in November 2013. Both cases are still under investigation as further test results are pending.  The cases travelled to Australia during the incubation period.

Toxic shellfish poisoning: One case of toxic shellfish poisoning was notified in November 2013. The case is still under investigation as further information is pending.

Yersiniosis: 63 cases of yersiniosis were notified in November 2013, three of these cases have since been found to not meet case criteria after further investigation. 47 cases were notified during the same month of the previous year (Figure 2). The highest number of cases was reported from Canterbury DHB (18 cases). Cases occurred in all age groups, with the highest numbers reported in the 70+ years (13 cases) and the 1-4 years (8 cases) age groups. Two cases were hospitalised. The biotype involved was identified in 53 (86.9%) of the cases: Yersinia enterocolitica biotype 1A (21 cases), Y. enterocolitica biotype 2 (13 cases), Y. enterocolitica biotype 3 and Y. enterocolitica biotype 4 (9 cases each) and Y. pseudotuberculosis (1 case). Among the cases where risk factor information was recorded, 44.0% (11/25) had consumed food from a food premises, 33.3% (8/24) had consumed untreated water, 22.2% (6/27) had contact with recreational water and 22.2% (6/27) had contact with faecal matter.