Communicable Diseases Surveillance - Highlights

This report published in Communicable Diseases Intelligence Volume 23, No 6, 10 June 1999 contains an analysis of notifiable diseases.

Page last updated: 21 June 1999

A print friendly PDF version is available from this Communicable Diseases Intelligence issue's table of contents.


Communicable Diseases Surveillance consists of data from various sources. The National Notifiable Diseases Surveillance System (NNDSS) is conducted under the auspices of the Communicable Diseases Network Australia New Zealand. The Virology and Serology Laboratory Reporting Scheme (LabVISE) is a sentinel surveillance scheme. The Australian Sentinel Practice Research Network (ASPREN) is a general practitioner-based sentinel surveillance scheme. In this report, data from the NNDSS are referred to as 'notifications' or 'cases', whereas those from ASPREN are referred to as 'consultations' or 'encounters' while data from the LabVISE scheme are referred to as 'laboratory reports'.

Prolonged outbreak of leptospirosis in Queensland

Lee Smythe, Leonie Barnett, Meegan Symonds, Michael Dohnt

World Health Organisation/Food and Agriculture Organisation Collaborating Centre for Reference and Research on Leptospirosis, Queensland Health Scientific Services PO Box 594, Archerfield Qld 4108

In Queensland between 50 and 120 notifications of leptospirosis are typically reported annually. In the period 1 January to 18 May this year 153 notifications have been reported to Queensland Health (Figure 1). This is in comparison to 34 notifications for the same period in 1998. Of the notifications, 80% have been reported from Far North Queensland (Figure 2), with the likely cause being the prolonged wet season in this region. The infecting serovars for Queensland are shown in Table 1.

Figure 1. Notifications of leptospiridiosis by month, 1 January to 18 May 1999

Figure 1. Notifications of leptospiriosis by month, 1 January to 18 May 1999

Figure 2. Notifications of leptospiridiosis by postcode, 1 January to 18 May 1999

Figure 2. Notifications of leptospiriosis by postcode, 1 January to 18 May 1999
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Table 1. Notifications of leptospirosis by serovar, 1 January to 18 May 1999

Serovar
% Notifications
positive cultures - unknown
26.5
zanoni
20.0
hardjo
16.1
australis
10.3
szwajizak
6.5
pomona
5.9
kremastos
3.2
canicola
3.2
robinsoni
1.9
tarassovi
1.3
grippotyphosa
1.3
celledoni
1.3
ballum
1.3
medanensis
0.6
bulgarica
0.6


Epidemiological investigations show that the banana (agriculture), meatworker and farming industries account for over 30% of the notifications. Clinical symptoms most commonly reported by respondents are headache (87%), chills (83%), severe fever (78%), sweats (72%), myalgia (71%) and arthralgia (59%) (Table 2). Pulmonary haemorrhage was reported in 9% of cases and was associated with the serovars australis and zanoni.

Table 2. Notifications of leptospirosis by symptoms, 1 January to 18 May 1999

Symptom
% Notifications
Headache
87
Chills
83
Severe Fever
78
Sweats
72
Myalgia
71
Arthralgia
59
Nausea
58
Vomiting
51
Back Pain
45
Conjunctival Suffusion
32
Mild Fever
26
Vision Disturbance
25
Respiratory Symptoms
23
Renal Involvement
16
Rash
9
Pulmonary Haemorrhage
9
Diarrhoea
4


Most notifications (75%) are in the 20-49 years age groups while school aged children (5-16 years of age) represent approximately 5% of the notifications. A 50% hospitalisation rate is reported with the duration of stay ranging between 1 day and 20 days with an average of 6 days. Of the 153 notifications, 57 isolates have been recovered from either blood, urine or CSF. This is in comparison to 6 isolates recovered for the same period in 1998. All serology based notifications have been confirmed by the Microscopic Agglutination Test.

Victorian measles outbreak

Stephen Lambert, Infectious Diseases Unit, Department of Human Services, Victoria

The Victorian measles outbreak, which began in February 1999, appears to have drawn to a close. The last onset date for a laboratory-confirmed case of measles linked with the outbreak was 2 May 1999.

There has been one further laboratory-confirmed case of measles in Melbourne in May, a 12 year old male who is visiting from Indonesia. He arrived in Australia on 8 May to stay with his three older sisters who are attending university in Melbourne. He developed prodromal symptoms on 15 May and there have been no secondary cases linked to him at this stage (7 June 1999). None of his sisters were unwell with a measles-like illness at the time of his arrival.

The preliminary total of notified cases for the outbreak is 75, with 63 (84%) of these in the 18 to 30 years age group. Some of the cases in this age group appeared to falsely believe they were immune to measles either through parental reporting of childhood infection, or through a false belief of previous immunisation. Many thought that measles immunisation was included in the schoolgirl rubella program, or that parental reports of being 'up-to-date' with all immunisations afforded them protection against measles.

A complete report of the outbreak will be published in Communicable Diseases Intelligence in the near future.


This article was published in Communicable Diseases Intelligence Volume 23, No 6, 10 June 1999.

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This issue - Vol 23, No 6, 10 June 1999