Collection of immunisation certificate. information by primary schools

Transcription

1 ISSN Volume 9 Number 1 January-March 2002 Collection of immunisation certificate information by primary schools Geetha Galgali,* Public Health Physician; Fraser Jack, Information Technology Project Leader, Community and Disability Services, Waitemata District Health Board The Health (Immunisation) Regulations 1995 require children born from January 1995 to present an immunisation certificate when starting attendance at an early childhood centre or primary school. A survey was conducted to evaluate collection of information from immunisation certificates by primary schools in the Waitemata District Health Board region, and to estimate the proportion of new school entrants who were fully immunised according to their certificates. A brief questionnaire was sent to all 138 schools in the region in November It covered collection of information from immunisation certificates during the first three school terms of The response rate was 78%. Results showed that of 3857 new school entrants enrolled during this time, 64% had produced an immunisation certificate, and of these 98% (2416/2472) were fully immunised. The minimum level of immunisation coverage among all school entrants, including those who had not presented an immunisation certificate, was therefore 63%. These results have several implications for health service providers and policy makers. Schools require assistance and support to improve the collection of immunisation certificates, primary care providers should increase their efforts to offer catch-up immunisation to five year olds, and the Ministry of Health should increase efforts to promote use of immunisation certificates if the level of immunisation coverage is to be improved. Previous efforts to determine immunisation coverage in New Zealand have focussed on the pre-school population. 1-6 One previous study examined the utilisation of immunisation registers in early childhood centres (ECC)s and used this to determine immunisation coverage. 7 International research suggests that legislation to require presentation of documentation of immunisation status at school entry is a useful method for ascertaining immunisation coverage among school-aged children, 8-10 and can be effective in improving immunisation coverage. 11 School-based registers of immunisation coverage, collated from immunisation certificates, may also allow rapid identification of children who might require urgent immunisation or exclusion during outbreaks of vaccine preventable disease in schools. 12 Introduction of certificates to record childhood immunisation status was one of five initiatives of Immunisation 2000, a comprehensive national strategy developed by the Public Health Commission in 1993 to improve immunisation coverage in New Zealand. 13 The Health (Immunisation) Regulations 1995 require parents of children born from January 1995 to show their child s immunisation certificate when starting * Correspondence: Dr Geetha Galgali, Community and Disability Services, Waitemata DHB, Private Bag , Henderson, Auckland. Geetha.Galgali@WaitemataDHB.govt.nz at ECC and on school entry. 14 From January 2000, all primary schools have been required to keep an immunisation register and record immunisation certificate information on their registers. The immunisation certificates contain the child s name and birth date, and immunisation status at 15 months and five years of age (Figure 1). Immunisations are not compulsory, but parents are required to make an active and informed choice and to have this choice recorded on the immunisation certificate. Children cannot be refused entry to school on the basis of possession or content of the immunisation certificates. This survey was the first attempt in New Zealand to evaluate collection Contents Collection of immunisation certificate information by primary schools 1 Surveillance and control notes 4 Surveillance data 6 Public health abstracts 8 Travel health 8 Page 1 New Zealand Public Health Report Vol. 9 No. 1 January-March 2002

2 Figure 1: Immunisation Certificate of information from immunisation certificates by primary schools and to measure immunisation coverage at school entry using information provided on the certificates. Methods An up-to-date list of all schools in the Waitemata District Health Board (WDHB) region (covering North Shore City, Waitakere City, and Rodney District territorial authority areas) was obtained from the Ministry of Education. Principals of all primary schools in the region were sent a brief questionnaire in November 2000 regarding collection of information on immunisation certificates for new school entrants during terms one to three in No attempt was made to follow-up principals who failed to respond to the survey. Survey participants were asked to record when certificates were requested (either at school enrolment or school entry), the number of attempts made to view each certificate, the number of new school entrants during terms one to three in 2000, the number of these children for whom immunisation certificate information had been successfully collected, the number of children with complete immunisation according to the certificates, and any other comments or suggestions about collection of immunisation certificate information. Information from questionnaires was entered into an Access database. Data were analysed using Access, and tabulated using Excel. Results Questionnaires were distributed to the principals of each of the 138 primary schools in the WDHB region. Of these, 107 (78%) were completed and returned. Across the region, the response rate was 85% (41/48) in the Waitakere City territorial authority area, 82% (41/50) in the North Shore City area and 63% (25/40) in the Rodney District area. Table 1: Time of request for immunisation certificates, Waitemata DHB primary schools Information requested: Number Percent Only at enrolment Only at school entry Both at enrolment and at school entry Total The time at which schools requested immunisation certificate information is shown in Table 1. Most schools (65%) requested the information only at the time of new entrant enrolment, 15% requested the information only at school entry and 20% requested the information at both enrolment and school entry. A variety of further approaches were used by schools to attempt to collect immunisation certificate information about school entrants, if this information had not been collected at the time of enrolment or school entry (Table 2). Forty-nine percent of schools made no further attempts to collect the information, other than at enrolment or school entry. The majority of the remaining schools followed up their initial requests with further reminders, either as phone calls, letters or in person. Table 2: Follow-up attempts made by primary schools in Waitemata DHB region to collect immunisation certificate information Attempts Number Percent No further attempts Follow-up phone call, letter or personal reminder Reminder placed in school newsletter 1 1 Reminders made at school visits or new entrant mornings 1 1 Total No further attempts made to collect immunisation certificate information, other than requests at student enrolment and/or school entry Collection of immunisation certificate information and immunisation status of new entrants in the WDHB region between term one and term three 2000 is shown in Table 3. There were 3857 term one to three new entrants enrolled in WDHB region primary schools that responded to the survey. Of these 3857 new entrants, 2472 (64%) produced an immunisation certificate for the school. This proportion varied from 69% in North Shore to 59% in Rodney. Of the 2472 children whose immunisation certificate was collected or sighted, 2416 (98%) had been fully immunised. Immunisation was complete in 100% of North Shore and Rodney children who had presented immunisation certificates. Using these data as a measure of immunisation coverage among the school-entry population, 63% of the 3857 new entrants in terms one to three in 2000 were confirmed to have been fully immunised. Confirmed immunisation coverage was lower in the Waitakere City (57%) and Rodney District (59%) territorial authority areas, and highest in the North Shore territorial authority area (69%). Table 3: Immunisation status of new entrants to primary schools in Waitemata DHB region in 2000, terms 1-3 North 1 Waitak 2 Rodney 3 Total Total new entrants New entrants with immunisation certificates sighted and information collected (% 4 ) 1145(69) 983(60) 344(59) 2472(64) New entrants fully immunised, as per immunisation certificates (% 5 ) 1145(100) 927(94) 344(100) 2416(98) 1 North Shore City territorial authority area 2 Waitakere City territorial authority area 3 Rodney District territorial authority area 4 As a percentage of new entrants in territorial authority area 5 As a percentage of new entrants with immunisation certificates sighted and information collected Comments and suggestions made by the schools about the requirement to collect immunisation certificate information are shown in Table 4. Ten schools (9%) had reservations about the need Table 4: Comments and suggestions from primary schools in the Waitemata DHB region about requirement to collect immunisation certificate information Comments and suggestions Number Percent No comment Creates unnecessary work, is a waste of time, or is not schools role 10 9 Very difficult for school 7 7 Difficult for parents 4 4 Immunisation certificates should be compulsory 4 4 Difficulties with children moving between schools and having immunisation information 3 3 Schools should be reimbursed for time 2 2 Health services should send representative to check school records 1 1 Total New Zealand Public Health Report Vol. 9 No. 1 January-March 2002 Page 2

3 to collect immunisation certificate information, and a further 11 schools (10%) considered that the requirement created difficulties for the school or parents. Four schools (4%) suggested that the requirement be made compulsory. Discussion This is the first attempt to evaluate the collection of immunisation certificate information by primary schools, and to use these certificates to estimate the immunisation coverage in the WDHB region. The accuracy of conclusions based on responses to mailed questionnaires depends upon many factors including the wording of the questions, the physical appearance of the questionnaire, and the response rate. 15 We limited our questionnaire to one page and achieved a high response rate of 78%, suggesting that bias due to non-responders will have been low, and that the survey results are likely to be a valid representation of the WDHB region as a whole. Research shows that responses to mail surveys are usually much lower than that observed here. 16,17 Immunisation certificate information was collected from less than two-thirds of the 3857 new school entrants enrolled in WDHB primary schools during terms one to three of the 2000 year. This proportion varied between the three territorial authority areas within WDHB, but was not greater than 69%. However, immunisation status was virtually complete among children who had presented immunisation certificates. It is likely that those who fail to produce a certificate are incompletely immunised, 9,10 and these are the very children whom the regulation is aimed at identifying. School entry immunisation legislation can provide an effective safety net to identify children with incomplete immunisation only if a high proportion of children produce a certificate. Experience with legislation requiring presentation of immunisation certificates at school and ECC entry is greater in Australia than in New Zealand, with implementation in Victoria in 1991 and in New South Wales in In evaluations, the proportion of children who had presented an immunisation certificate ranged from 87% among preparatory year children in Victoria 18 to 72% among kindergarten children in Auburn, New South Wales (NSW). 19 The NSW study conducted individual reviews of all school immunisation documentation, and the authors considered that evaluations relying on questionnaire-based data collection were likely to overestimate collection of immunisation certificate information. 19 If this assumption is equally applicable to New Zealand, it suggests that the actual proportion of children with school records of immunisation certificate information may be lower than the 64% observed in the WDHB study. A further study in Victoria showed that students in rural schools were less likely than those in urban settings to have missing immunisation certificates, which was attributed to smaller numbers of enrolments and the relative ease of following up children in smaller communities. 10 Schools in the rural regions were more than twice as likely to have their students fully immunised. These findings were not replicated in the WDHB study: the percentage of new entrants with certificates in schools in the relatively rural Rodney District (60%) was similar to that in schools in the urban Waitakere City (59%) territorial authority area, and lower than that in schools in North Shore City (69%), also an urban territorial authority. Most schools in the WDHB study requested presentation of immunisation certificates at either enrolment or school entry, or at both times. However, fewer than half of the schools surveyed made further attempts to collect the information if the immunisation certificates had not been presented at this initial contact. Schools that did make further attempts used a variety of techniques, mainly by additional phone calls, written letters or personal reminders. Australian research indicates that informing and encouraging parents of children who did not initially produce documentation produces a tangible improvement in the certificate rates of that year, and also of children enrolling in the same school in subsequent years. 9 As a specific technique, reminder letters can be an effective means of increasing the proportion of families who present an immunisation certificate, as shown in a NSW study that found a 25% response rate to reminder letters sent to families of children with no certificate or an incomplete certificate. 20 As collection of immunisation certificate information was incomplete, the value of this information as a measure of immunisation coverage among the school-entry population is weakened. Data from this study suggest that as few as 63% of children in the WDHB region are fully immunised at school entry, taking the worst case assumption that none of the 1385 children without immunisation certification were completely immunised. This is comparable with data from a 1996 survey in Northland and Auckland indicating that 63% of children were fully immunised at age 2 years. 2 Research conducted in Victoria in and NSW in estimated that immunisation coverage among new entrants to primary schools, based on immunisation certificate information, was 85% and 80% respectively. Our figure of 63% is considerably lower than these, and is far lower than the immunisation coverage required to prevent spread of vaccine-preventable diseases. The NSW study accepted other non-statutory documents for completed immunisations. This may partly account for their higher rate of completed immunisations; however it is unlikely to be the sole reason for the large difference. Over a quarter of schools surveyed had some difficulty with the requirement to collect information from immunisation certificates. Ten percent of schools felt that the work was either unnecessary, a waste of time or not the school s role. In addition, 7% felt that it was very difficult for the school and 2% thought that schools should be reimbursed for the time taken. The requirements are demanding for both parents and schools. A detailed study of schools attitudes toward immunisation certificates was not attempted here. Barriers experienced by schools in meeting their requirements to collect immunisation certificate information should be further explored. In general, however, these findings suggest that schools may require more assistance from district health boards, the Ministry of Health and Ministry of Education. Our survey showed that although immunisation coverage among children who produced certificates is very high (98%), immunisation certificate information was collected from fewer than two thirds of new entrants, so overall immunisation coverage in this population could be as low as 63%. These findings show that considerable work is required both to improve collection of information from immunisation certificates, and to improve immunisation coverage. Schools should receive more information regarding the importance of immunisation certificates, and the time and effort taken to complete immunisation registers should be acknowledged. Primary care providers should be encouraged to continue offering catch-up immunisations, and to ensure that immunisation certificates are completed. The Ministry of Health should work with the Ministry of Education to increase efforts to collect immunisation certificates from all new school entrants. On its own, school entry legislation has limited effectiveness in improving vaccination coverage because it does not aim to immunise children age-appropriately. Up to date immunisation coverage information in the pre-school ages is also important in order to improve age-appropriate immunisation and reduce the burden of vaccine-preventable diseases in children. Such information should be collected as part of a comprehensive immunisation surveillance system. 21 Acknowledgements: The authors gratefully acknowledge the support and encouragement for this project from Mrs Carol Wilson and Ms Roz Sorensen. We take this opportunity to thank all the schools for their participation. References 1 Stehr-Green P, Baker M, Belton A, et al. Immunisation coverage in New Zealand: results of the regional immunisation coverage surveys. Commun Dis N Z 1992; 92 Suppl 2: Rainger W, Solomon N, Jones N, et al. Immunisation coverage and risk factors for immunisation failure in Auckland and Northland. N Z Public Health Rep 1998; 5: Stehr-Green P, Briasco C, Baker M, et al. How well are we protecting our children? An immunisation coverage survey in Hawke s Bay. N Z Med J 1992; 105: Malcolm M. Immunisation surveillance: a comparison of four methods in Canterbury. N Z Med J 1993; 106: Kljakovic M, McLeod D. A general practice case-control study of delayed immunisation in under two year old children. N Z Med J Page 3 New Zealand Public Health Report Vol. 9 No. 1 January-March 2002

4 1997; 110: Mansoor OD. Ask and you shall be given: practice based immunisation coverage information. N Z Med J 1993; 106: Taylor P. Project to identify strategies for improving compliance with Health (Immunisation) Regulations 1995 [unpublished report]. Auckland; Auckland Healthcare Services: Hinman AR. What will it take to fully protect all American children with vaccines? An update. Am J Dis Child 1993; 147: Thompson SC, Goudey RE, Stewart T. Legislation for school entry immunisation certificates in Victoria. Aust J Public Health 1994; 18: Thompson SC, Cocotsi L, Goudey RE, et al. An evaluation of school entry immunisation certificates in Victoria. Aust J Public Health 1994; 18: Watt PD. An evaluation of 1994 school entry immunization certificates on the Central Coast of New South Wales. J Paediatr Child Health 1996; 32: Shah S, Raman S, Moreira C, et al. School immunisation certificates a review over time in a disadvantaged community. Aust N Z J Public Health 2001; 25: Public Health Commission. Immunisation. The Public Health Commission s advice to the Minister of Health Wellington: Public Health Commission; Ministry of Health. Immunisation Handbook Wellington: Ministry of Health; Fox C. Questionnaire development. J Health Soc Policy 1996; 8: Asch DA, Jedrziewski MK, Christakis NA. Response rates to mail surveys published in medical journals. J Clin Epidemiol 1997; 50: Sitzia J and Wood N. Response rate in patient satisfaction research: an analysis of 210 published studies. Int J Qual Health Care 1998; 10: Stewart T. The school entry immunisation certificate in Victoria. Comm Dis Intell 1993; 17: Leckie R, Shah S, Jalaludin B. School entry immunisation certificates: a useful tool for immunisation surveillance? Comm Dis Intell 1996; 20: Miksevicius H, Johnson P, Watt PD. Limitations of school entry immunization certificates. J Paediatr Child Health 1997; 33: Turner N, Baker M, Carr J, et al. Improving immunisation coverage: what needs to be done? N Z Public Health Rep 2000; 7: Surveillance and control notes An outbreak of salmonellosis in Auckland linked to consumption of umu food imported from the Pacific Islands Auckland District Health Board investigated an outbreak of gastroenteritis due to Salmonella Weltevreden in late February and early March, The outbreak was identified on 4 March 2002 through routine follow-up of two persons, one notified with salmonellosis and the other a self-reported case of gastroenteritis, who were found to be linked. An investigation was carried out to determine the source of illness and identify links between cases in time, place and person. Information was collected using a standardised questionnaire covering demographics, symptoms, and exposures over the three-day period prior to the onset of illness. Case finding was undertaken among friends and members of the extended families of the index cases. A confirmed case was a person who consumed imported umu food at one of six defined meals, and who developed diarrhoea with Salmonella spp. on stool culture. A probable case was defined as a friend or member of the extended family of a confirmed case, who consumed imported umu food at one of six defined meals, and who developed diarrhoea (defined as at least three loose motions in a 24 hour period) on or after 22 February, A group of 20 people were identified in relation to this outbreak, all of whom had consumed a common range of foods on one or more of six different occasions between 22 February and 1 March Four could not be located for interview. Of those interviewed, 13 met the case definition, five of whom were confirmed as infected with Salmonella Weltevreden on stool culture. There was a strong link between illness and consumption of Palusami (umu-cooked packs of taro in coconut milk wrapped in taro leaves) that had been privately imported from Apia, Western Samoa on Friday 22 February The overall attack rate for palusami was 93% (14/15). Illness in all cases occurred within 48 hours of consumption. Salmonella Weltevreden was isolated from two umu packs remaining in the freezer of one of the cases. A detailed HACCP-based food safety audit was not possible, but the investigation established that 24 umu packs had been imported. These packs were purchased freshly cooked from a stall at the Apia market on Thursday 21 February at approximately 2100 hrs and imported by air the following day as check-in luggage in a cardboard box. The food was not refrigerated at any stage while in Samoa or while en route to New Zealand. The palusami was at ambient temperature for up to 22 hours prior to consumption on 22 February If properly done, umu cooking should provide temperatures high enough to eliminate Salmonella spp. Post-cooking contamination by an infected foodhandler in this outbreak could not be excluded. In either event, time and temperature abuse would have permitted Salmonella growth in the food. The palusami was consumed fresh or thawed overnight. Three cases consumed the fresh palusami without reheating, and the remainder consumed the palusami reheated. Palusami was reheated either using a frying pan at high temperature for 5-10 minutes, or in an oven at 150 o C for 2-5 minutes, or if frozen, cooking for 40 minutes at o C. The palusami was reheated until warm and the temperature reached was unlikely to be sufficient to sterilise the food. The private importation of umu packs from Samoa into New Zealand is both legal and common. The food is considered a delicacy and returning flights will have many passengers carrying umu packs subsequently distributed to family and friends. The Ministry of Agriculture and Forestry border requirements for importation are that the food is declared and that it be cooked prior to importation so that pests and plant diseases are eliminated. Ongoing surveillance by the Enteric Reference Laboratory through Salmonella typing identified one further outbreak of S Weltevreden infection involving two cases, one of which was confirmed. The confirmed case occurred on 5 April 2002 in a Samoan man and another family member who had consumed palusami umu packs on 4 April that had been privately imported from Apia by a friend in early February, Umu cooking and transport details were unknown. The palusami had been frozen after arrival and only warmed prior to consumption. This report is the first to document an outbreak of salmonellosis in New Zealand linked to consumption of imported umu food from the Pacific Islands. The outbreak highlights the importance of adhering to critical control methods during the importation of umu-cooked food. These control points include prompt refrigeration after cooking, chilling while en route to New Zealand, thorough thawing and adequate reheating prior to consumption. These food safety themes will be promoted during the upcoming Pacific Island food safety campaign run by Auckland Regional Public Health (reported by Lionel Ng and Greg Simmons, Public Health Protection, Auckland District Health Board). New Zealand Public Health Report Vol. 9 No. 1 January-March 2002 Page 4

5 Surveillance and control notes New Zealanders infected in United States outbreak of coccidioidomycosis Four New Zealanders were infected as part of an outbreak of coccidioidomycosis in the United States (US). The outbreak occurred in people who attended a model aeroplane flying event in California in October 2001.The UK Public Health Laboratory Service and the US Centers for Disease Control have coordinated an international investigation which involved collection of serum specimens and administration of questionnaires to attendees. Seven New Zealand residents had attended the event, six of whom were located and provided serum specimens and completed questionnaires. Of these, four were found to have positive serological titres. Coccidioidomycosis is caused by inhalation of arthrospores of Coccidioides immitis, and outbreaks have typically occurred following events that generate airborne dust. Forty percent of newly infected persons acquire a self-limited influenza-like syndrome with fever, chest pain, cough, malaise, chills, night sweats, arthralgias, and rash. Infants, pregnant women, persons of Filipino and African descent and immunosuppressed individuals are at increased risk for disseminated infection, which may involve the meninges, bones, joints, skin, and soft tissues. Treatment with antifungal drugs usually is required only for severe or disseminated disease. C immitus is one of a group of systemic fungal pathogens referred to as dimorphic fungi because they take on two different temperature-dependent forms. Other members of the group are Histoplasma capsulatum, which causes the disease histoplasmosis, Blastomyces dermatitidis (blastomycosis) and Paracoccidioides brasiliensis (paracoccidioidomycosis). While widely distributed geographically, none of the dimorphic fungi with human pathogenicity have environmental reservoirs in New Zealand [see N Z Public Health Rep 1994; 1: 25-6]. Cases of histoplasmosis and coccidioidomycosis have been diagnosed in New Zealand, but only among individuals with a history of travel to endemic areas (background information on coccidioidomycosis obtained from the CDC website, available at: mm5049a2.htm). incubation period. The total for 2001 of is the second highest annual total. The previous highest annual total was in 1998, when cases were notified. Figure 1 shows campylobacteriosis notifications by year since Figure 1: Campylobacteriosis notifications by year, Campylobacteriosis has a seasonal distribution in New Zealand, with the highest rates occurring during the late spring and early summer months of November, December, and January. Of campylobacteriosis notifications between January 1997 and December 2001, 28.2% have occurred during January to March, 18.8% during April to June, 20.9% during July to September, and 32.1% during October to December. Figure 2 shows the distribution of campylobacteriosis notifications, by month, for the years 1997 to Figure 2: Campylobacteriosis notifications by month, January 1997 to December 2001 Campylobacteriosis occurring at record levels in December, 2001 There were 1475 cases of campylobacteriosis notified during December 2001, bringing the year to date total to cases. In contrast, 919 cases were notified during December This monthly total is the highest reported total for any month since campylobacteriosis became notifiable in Of the 1475 cases notified in December, 480 (32.5%) were notified from the combined Auckland health districts, 174 (11.8%) from Canterbury, 164 (11.1%) from Wellington, and 137 (9.3%) from Waikato health districts. Rates higher than the national rate of per were seen in Wellington (460.7), South Canterbury (345.8), Waikato (340.1), Hutt (335.6), Taupo (322.5), North West Auckland (314.0), Central Auckland (305.1), Hawkes Bay (292.7), and Tauranga (284.6) health districts. Risk factor information was infrequently recorded on case report forms, with only 21.3% (314/1475) of notifications in December including information on human contact and only 32.5% (479/1475) including information on travel. Of these, 6.3% (20/314) had a history of contact with other symptomatic people and 6.4% (31/479) had been overseas during the The New Zealand incidence of notified campylobacteriosis is higher than that of any other notifiable disease, and exceeds the campylobacteriosis incidence reported by other developed countries. While the reasons for the high incidence of campylobacteriosis in New Zealand are unclear, the highest risks for Campylobacter transmission appear to be related to consumption of undercooked poultry, consumption of undertreated drinking water, overseas travel, and animal contact. Food safety education to reduce Campylobacter transmission should reinforce the following messages: clean (hands, surfaces and utensils before preparing food); chill (raw meat and leftovers, and defrost fully before cooking); cook (thoroughly, so that juices run clear); and cover (meat pieces before refrigeration, and discard perishable items that have been left at room temperature for longer than two hours). Notification of campylobacteriosis cases is important to ensure high-risk cases are identified and managed appropriately and outbreaks are promptly identified. Page 5 New Zealand Public Health Report Vol. 9 No. 1 January-March 2002

6 Surveillance data National surveillance data - January to March 2002 Disease 1 Current year Previous year Trends - January to March st Quarter Cumulative 1st Quarter Cumulative 2002 total since Current 2001 total since Previous cases 1 January rate 3 cases 1 January rate 3 AIDS Campylobacteriosis Cholera Creutzfeldt-Jakob disease Cryptosporidiosis Dengue fever Gastroenteritis 4 Giardiasis H influenzae type b disease Hepatitis A Hepatitis B (acute) 5 Hepatitis C (acute) 5 Hydatid disease Influenza 6 Lead absorption Legionellosis 6 Leprosy Leptospirosis Listeriosis Malaria Measles Meningococcal disease 7 Mumps Paratyphoid Pertussis Rheumatic fever Rubella Salmonellosis Shigellosis Tetanus Tuberculosis Typhoid VTEC/STEC infection Yersiniosis Notes: 1 Other notifiable infectious diseases reported in January - March: Nil 2 These data are provisional 3 Rate is based on the cumulative total for the current year (12 months up to and including March 2002) or the previous year (12 months up to and including March 2001), expressed as cases per Cases of gastroenteritis from a common source or foodborne intoxication eg, staphylococcal intoxication or toxic shellfish poisoning 5 Only acute cases of this disease are currently notifiable 6 Surveillance data based on laboratory-reported cases only 7 Totals and rates are based on the EpiSurv report date except for meningococcal disease which uses the earliest available date. 8 Percentage change is the difference between the number of cases in the current year (12 months up to and including March 2002) and the previous year (12 months up to and including March 2001). This difference is expressed as a percentage of the number of cases in the previous year. New Zealand Public Health Report Vol. 9 No. 1 January-March 2002 Page 6

7 Surveillance data Surveillance data by health district - January to March 2002 quarter Cases this quarter Current rate 1 Disease Cases for Quarter, 2 and current rate 1,2 by health district 3,4 Northland NW Auck Central Auck South Auck Waikato Tauranga Eastern BoP Gisborne Rotorua Taupo AIDS Campylobacteriosis Cholera Creutzfeldt-Jakob disease Cryptosporidiosis Dengue fever Gastroenteritis Giardiasis H influenzae type b disease Hepatitis A Hepatitis B Hepatitis C Hydatids Influenza Lead absorption Legionellosis Leprosy Leptospirosis Listeriosis Malaria Measles Meningococcal disease Mumps Paratyphoid Pertussis Rheumatic fever Rubella Salmonellosis Shigellosis Tetanus Tuberculosis Typhoid VTEC/STEC infection Yersiniosis Notes: 1 Current rate is based on the cumulative total for the 12 months up to and including March 2002, expressed as cases per These data are provisional 3 Aids data are reported for the greater Auckland and Wellington areas, rather than by health district 4 Further data are available from the local medical officer of health 5 Surveillance data based on laboratory-reported cases only 6 These totals and rates are derived from the EpiSurv report date as opposed to the earliest available date used in the meningococcal disease section Taranaki Ruapehu Hawkes Bay Wanganui Manawatu Wairarapa Wellington Hutt Nelson-Marl West Coast Canterbury South Cant Otago Southland Page 7 New Zealand Public Health Report Vol. 9 No. 1 January-March 2002

8 A dose response relationship was found between alcohol consumption and the relative risk (RR) of death while boating by a large population based case control study in the United States. The study compared recreational boating deaths among people aged 18 years or older from in Maryland and North Carolina with control interviews. The estimated RR of death increased markedly as the blood alcohol concentration (BAC) increased, from an odds ratio (OR) of 1.3 (95% confidence interval (CI) at a BAC of 10mg/dl to 52.4 (95% CI ) at 250mg/dl. The estimated RR was similar for both passengers and operators and did not vary by boat type or whether the boat was moving or stationary. The authors conclude that measures that reduce drinking by all boat occupants are more likely to reduce boating fatalities than efforts that target operators only (Smith GS, Keyl PM, Hadley JA, et al. Drinking and recreational Public health abstracts Drinking increases the risk of dying while boating boating fatalities: A population based case control study. JAMA 2001; 286: ). Editorial note: Findings from a New Zealand study support the major role that alcohol plays in drowning and boating incidents. The study found that in Auckland for the period , 27% of year olds who died while boating had a BAC of more than 80mg/ dl (legal drinking limit) and 43% had a positive BAC. Falls from dinghies and recreational motor boats were highlighted as a concern by the study as 67% of those who fell were intoxicated with a BAC greater than 100mg/dl (Smith GS, Coggan C, Koelmeyer T, et al. The role of alcohol in drowning and boating deaths in the Auckland Region. Boating ( ) All Drownings ( ). An Updated Report to the Alcohol Advisory Council of New Zealand of New Zealand. Auckland: Injury Prevention Research Centre, Comparison of community gastroenteritis cases with those consulting general practitioners Concurrent community-based (CB) and general practice (GP) based studies of gastroenteritis in the Netherlands were compared to identify factors associated with GP consultation, to study the effects on the frequency of detected pathogens, and to estimate under-ascertainment by GPs. The CB study used a prospective population-based cohort approach, and stool specimens were collected from identified cases on days 1, 8, 15, and 22 after onset of symptoms. CB-study cases were compared with cases enumerated by the GP study. Overall, 5% of community cases consulted a GP, and consultation rates among children under 1 year of age were higher (15.9%) than among other age groups. Cases who consulted were likely to have more severe illness than those who did not consult. Pathogenic bacteria and parasites were more frequently and Norwalk-like virus (NLV) was less frequently identified among specimens from GP-study cases than from CB-study cases. Bacterial and viral pathogens were less frequently detected on day 8 specimens than on day 1 specimens, among CB-study cases, and 42% of cases found to have NLV in their day 8 specimens did not have a Travel health positive day 1 sample. The incidence of gastroenteritis in general practices was estimated between 14 and 35 per 1000 person years (De Wit MAS, Kortbeek LM, Koopmans MPG, et al. A comparison of gastroenteritis in a general practice-based study and a communitybased study. Epidemiol Infect 2001; 127: ). Editorial note: This study is one of the few population-based prospective studies of gastroenteritis in the world. A unique aspect of this study was the collection of multiple stool specimens from cases identified in the community to maximise identification of aetiologic pathogens. In New Zealand, estimates of the burden of disease associated with gastroenteritis rely on GP investigation and diagnosis of cases. If the results of this study can be applied here, New Zealand GPs are likely to see only a small proportion of gastroenteritis occurring in the community, and NLV cases seen in general practice will be a particularly small proportion of community cases. These findings support population-based measures to reduce gastroenteritis, and encourage examination of the impact of NLV on the community. Reduced antibiotic susceptibility in Salmonella isolated from travellers returning form Southeast Asia This study was based on 629 Salmonella isolates collected during from Finnish travellers returning from overseas which were compared with 581 domestically acquired isolates. Reduced ciproflaxacin susceptibility (MIC³0.125 mg/ml) among travellers isolates was found to have increased from 3.9% to 23.5% (p<0.001). The increase was most marked among isolates from Southeast Asia. Isolates from Thailand with reduced susceptibility increased from 5.6% to 50.0%. This reduced susceptibility was non-clonal in character and primarily involving mutations in chromosomal genes. The emergence of mutation-based resistance may be fostered by selection pressure caused by use of antimicrobial agents in either human medicine or agriculture. In Asia, several fluoroquinolones have been approved for animal use. Widespread use of first generation quinolones (notably nalidixic acid) in the treatment of human disease could also explain the observed pattern (Hakanen A, Kotilainen P, Huovinen P, et al. Reduced fluoroquinolone susceptibility in Salmonella enterica serotypes in travellers returning from Southeast Asia. Emerg Infect Dis 2001; 7: ). Editorial note: This paper provides further evidence of the spread of multi-drug resistance pathogens from one continent to another and the increasingly important role that human travel can play in this process. Those treating infections in returning travellers need to consider the increased potential for antibiotic resistance and obtain specimens for testing where reduced susceptibility may be clinically important. Scientific Editors: Managing Editor: Editorial Committee: New Zealand Public Health Report is produced quarterly by ESR for the Ministry of Health. Internet website: Michael Baker, Public Health Physician, ESR Craig Thornley, Public Health Physician, ESR Rabia Khan, Public Health Researcher, ESR Sally Gilbert, Senior Advisor, Ministry of Health Douglas Lush, Senior Advisor, Ministry of Health Phone: (04) Fax: (04) Phone: (04) Fax: (04) Reprinting: Articles in the New Zealand Public Health Report may be reprinted provided proper acknowledgement is made to the author and to the New Zealand Public Health Report as source. Contributions to this publication are invited, in the form of concise reports on surveillance, outbreak investigations, research activities, policy and practice updates, or brief review articles. Please send contributions to: Scientific Editor, New Zealand Public Health Report, ESR, PO Box , Porirua, Wellington, New Zealand. Phone: (04) ; Fax: (04) ; michael.baker@esr.cri.nz The content of this publication does not necessarily reflect the views and policies of ESR or the Ministry of Health. New Zealand Public Health Report Vol. 9 No. 1 January-March 2002 Page 8