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Eurosurveillance Weekly: Thursday 19 July 2001. Volume 5, Issue 29
Contents:
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Index Medicus and MEDLINE to list Eurosurveillance (monthly)
Update on the outbreak of legionnaires' disease in Murcia, Spain
Salmonella Typhimurium outbreak in Sweden from contaminated jars of helva (or halva)
Outbreak of Q fever in Germany
Rapid reporting EU surveillance system for meningitis W135: 2a: P1.2, 5 – update
Index Medicus and MEDLINE to list Eurosurveillance (monthly)
The National Library of Medicine has selected Eurosurveillance (monthly) to be indexed and included
in Index Medicus and MEDLINE on the MEDLARS system. This development is an endorsement of
the importance and quality of the information disseminated in the journal and is very encouraging
news for all past and future contributors. Medline access to the valuable material that appears in
Eurosurveillance (monthly) (http://www.eurosurveillance.org/eurosurveillance.htm) will extend its
impact and broaden its multilingual readership.
Eurosurveillance was established in 1996 following a call from the European Parliament to improve
the provision of information about the epidemiology of communicable diseases in Europe in response
to threats from emerging and re-emerging infections and the potential for international travel and trade
to facilitate their spread. Eurosurveillance aims to increase awareness of communicable disease
incidence trends and outbreaks, primarily in European countries, to foster closer links between those
who work in the prevention and control of communicable diseases, and to promote better working
practices. Its target readership includes public health practitioners, infectious disease specialists,
microbiologists, and makers of related policy.
The editorial board of Eurosurveillance consists of the editors of national communicable disease
surveillance bulletins in the European Union. All papers submitted are peer reviewed by independent
experts. Eurosurveillance (monthly) is sent free of charge to over 10 000 recipients throughout Europe
and beyond and is available in its entirety on the internet. The paper edition is published in English
and French, and the electronic edition in English, French, Spanish, Portuguese, and Italian. The
Eurosurveillance project is coordinated by two Anglo-French teams based at the Institut de Veille
Sanitaire (InVS, National Public Health Institute) in Paris, France, and the Public Health Laboratory
Service Communicable Disease Surveillance Centre (PHLS CDSC) in London, United Kingdom.
Reported by Noël Gill ([email protected]), Eurosurveillance editorial office.
Update on the outbreak of legionnaires' disease in Murcia, Spain
Between the end of June and the first few days of July a very large and explosive outbreak of
legionnaires' disease occurred in Murcia, a Spanish city of 360 000 people (1). As of 18 July a total of
745 cases of pneumonia had been diagnosed, of which 315 have been confirmed as legionnaires’
disease by detection of legionella antigen in urine. Dates of onset of illness of confirmed cases ranged
from 26 June to 16 July, with a peak on 5-6 July (figure 1). From 6 July the incidence declined rapidly.
One death has been reported in a case in which legionella pneumophila serogroup 1 has been
isolated. A total of 12 cases were admitted to intensive care units. Seventy-six per cent of cases were
male, and about two thirds of cases were aged over 50 years.
Nearly 70% of all cases lived in a small area to the north and northwest of the city centre. Preliminary
information from patient interviews indicated that the other cases had visited the city centre in the last
week of June or the first few days of July. The likely source of infection for the outbreak is a cooling
tower in the city centre. Several cooling towers in that area were positive by PCR but no legionella
pneumophila sg1 have so far been isolated. Control measures have been applied to this and all other
cooling towers in the vicinity, and also to other potential sources of infection in the area.
Murcia is the host city for this year’s European Youth Olympic Days, to be held from 22-27 July.
Because of concern for the health of the several thousand sports people and other visitors due to
arrive in Murcia, the European Olympic Committee (EOC) arranged for an international group of
legionella experts to visit Murcia between 11-15 July to assess rapidly the impact of the outbreak and
discuss control measures with the local public health team. The international group were a total of five
epidemiologists and microbiologists, two from the UK Public Health Laboratory Service, one from the
Netherlands National Institute of Public Health and one each from the National Centres of
Epidemiology and Microbiology in Spain. All are national representatives in the European Surveillance
Scheme for Travel Associated Legionnaires’ Disease and members of the European Working Group
for Legionella Infections (http://www.ewgli.org/). They concluded that the local health authorities had
taken rapid steps to investigate and control the outbreak, and had implemented appropriate control
measures to prevent the occurrence of further cases. The outbreak now seems to be over. On the
basis of these findings, the international group recommended to the EOC and to the International
Olympic Committee (IOC) that the games should continue. The IOC accepted the recommendation,
and the games are to go ahead as planned.
<<Insert figure 1>>
Comment
This seems to be the world’s largest outbreak of legionnaires' disease since the disease was first
recognised in 1976. Remarkably, only one death is associated with this outbreak, which may be due
in part to the fast diagnosis and adequate treatment of the patients concerned. Another very large
outbreak, the Melbourne aquarium outbreak of 2000 (2), was also recognised early and showed a
case fatality rate of <2% (3). Moreover, in Australia and Spain, many pneumonia patients are treated
empirically with antibiotics that have activity against legionella. In contrast, the Dutch flower show
outbreak of 1999 (4,5) was only recognised when a large majority of the cases were already ill and in
that outbreak the case fatality rate was 11% (6). Empirical therapy for pneumonia in the Netherlands
is with beta-lactam antibiotics rather than macrolides. Other factors may also have contributed to the
absence of deaths in the Murcia outbreak. The legionella strain may have been less virulent, and
patients may have had prior exposure to this strain.
References:
1.
2.
3.
4.
5.
6.
Cano Portero R, Joseph C. Community outbreak of legionnaires’ disease in Murcia, Spain. Eurosurveillance Weekly
2001; 5: 010712. (http://www.eurosurv.org/2001/010712.html)
Joseph C. Outbreak of legionnaires’ disease associated with aquarium in Australia. Eurosurveillance Weekly 2000;
4: 000504. (http://www.eurosurv.org/2000/000504.html)
Tallis G, Greig J, Zwolak B, Carnie J, Hart W, Tan A, et al. A descriptive analysis of the Melbourne aquarium
outbreak of Legionnaires' disease. Fifth international conference on legionella infections. Ulm, Germany, September
2000. (http://www.uni-ulm.de/legionella/abstracts/v-tallis.doc)
van Wijngarden J. Outbreak of legionnaires’ disease in the Netherlands. Eurosurveillance Weekly 1999; 3: 990318.
(http://www.eurosurv.org/1999/990318.html)
Wijgergangs L. Legionnaires’ disease in the Netherlands - update. Eurosurveillance Weekly 1999; 3: 990401.
(http://www.eurosurv.org/1999/990401.html)
den Boer JW, Yzerman EPF, Schellekens J, Lettinga KD, Boshuizen H, van Steenbergen J, et al. A large outbreak of
Legionnaires' disease at a Dutch flower show. Fifth international conference on legionella infections. Ulm, Germany,
September 2000. (http://www.uni-ulm.de/legionella/abstracts/v-denboer.doc)
Reported by Carmen Navarro ([email protected]) and Ana Garcia-Fulgueiras
([email protected]), Regional Health Council of Murcia, Spain; Jacob Kool ([email protected]),
Rijksinstituut voor Volksgezondheid en Milieu, Netherlands; Carol Joseph ([email protected]),
Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre, London,
England; John Lee ([email protected]), PHLS Water and Environmental Microbiology Research Unit,
London, England; Carmen Pelaz ([email protected]), National Centre of Microbiology, and Odorina
Tello ([email protected]), National Centre of Epidemiology, Health Institute of Carlos III, Madrid, Spain.
Salmonella Typhimurium outbreak in Sweden from contaminated jars of helva
(or halva)
In early June 2001, at least 10 people resident in the south of Sweden were found to be infected with
Salmonella Typhimurium definitive phage type (DT)104. They were mostly children with a
predominance of Arabic names. An earlier outbreak of S. Typhimurium infection, involving both DT9,
DT30, and probably also not specifically typeable (NST) strains of S. Typhimurium that had a
common phage type pattern, was associated with the consumption of tahini (sesame paste), with
most cases also in the south of Sweden. It was therefore suspected that the new cases had acquired
the infection in a similar way. The first interviews showed, however, that the cases had not been
eating tahini, but imported helva (or halva)– a type of dessert or sweet made from sesame seeds.
The first case in the recent outbreak of S. Typhimurium DT104 infection fell ill on 13 April and the
latest reported case on 19 June. The investigation showed that 27 people (23 from the south of
Sweden – two of them asymptomatic – and four from another county) had become infected after
consuming helva. Three of the four people in the nearby county belonged to the same family. The
phage typing has been completed for all but two of the patients, and all 25 have S. Typhimurium
DT104. The age of the cases ranged from 5 months to 50 years, with 15 of the cases being younger
than 10 years. Eleven of the cases were men and 16 women, none of whom died.
Salmonella of the same type has also been directly isolated from five jars of helva, four with pistachio
and one with cocoa flavouring. Information about salmonella isolated from helva (pistachio flavour)
was first disseminated by the Swedish Food Administration on 11 June, with notification on 20 June
that cocoa flavoured helva was also contaminated.
Initial information about the product stated that it had been distributed solely in the very south of
Sweden, but the appearance of four cases from another county showed that this was incorrect. This
uncertainty about the distribution area underlines the difficulty of informing all at risk, particularly those
who may still have the product at home. Language problems also added to the difficulties of
disseminating prevention information.
Full details of the contaminated helva product, which was distributed in 350 g and 750 g jars, are
available on the website of the Swedish Food Administration (http://www.slv.se/livstecknet/). On 19
June an international alert notification was distributed through the European Commission’s Rapid
Alert System for Food. The extent of international distribution of the contaminated product is unclear
at present.
In recent years, Smittskyddsinstitutet (SMI, Swedish Institute for Infectious Disease Control) has seen
an increase of salmonella infection – from outbreaks and from food samples associated with different
types of imported vegetables, spices, and seeds, including tahini, fresh and dry spices, banana
leaves, and bean sprouts.
Reported by Yvonne Andersson ([email protected]) and Birgitta de Jong,
Smittskyddsinstitutet (SMI), Stockholm, Sweden; Lasse Hellström and Ulla Stamer, County Medical
Officers' Office of Skåne region; Ralfh Wollin and Johan Giesecke, SMI, Stockholm, Sweden.
Outbreak of Q fever in Germany
Two weeks ago Eurosurveillance Weekly reported on three cases of Q fever in the United Kingdom,
which affected farm workers helping to cull cattle during an outbreak of foot and mouth disease in the
country (1). Elsewhere in Europe, Q fever has been associated with sheep flocks passing populated
areas (1). A prolonged outbreak in Germany between December 2000 and May 2001 was recently
reported in Germany’s national surveillance bulletin (2). The outbreak affected three adjacent county
districts in the German state of North-Rhine Westphalia, and sheep were implicated as its likely
source.
Altogether 73 cases were notified to the Robert Koch-Institut (RKI) in Berlin by the district where the
first outbreak occurred; five of these did not have clinical symptoms. The epidemic peaked from 30
January to 17 February 2001 (week 5-7); after 1 May the number of new cases had dropped to one or
two per week. Veterinary investigations of blood specimens showed that several flocks of sheep in the
district were the likely source of infection. The likely transmission route was inhaled dust containing
Coxiella burnetii from contaminated afterbirth that had been deposited during the lambing season.
Local physicians and the public were kept informed by the health authorities and the media. There
was a potential risk of transmission to a large number of people attending an open air theatre festival
season in the town of Hallenberg, an annual event taking place between June and September, but no
additional cases were notified subsequently. As a result of strict preventive measures imposed on
sheep farmers in the area, after the end of the lambing season the number of notified cases
decreased; the last case was notified at the end of May (week 21).
Two neighbouring country districts reported 25 cases and two cases of Q fever, respectively, to RKI in
weeks 7-24, most of whom lived in close proximity to the first district. Preventive measures were
imposed on sheep farmers, and the public and local physicians were informed by the local authorities
in both these districts. No further cases have been reported since week 24.
In a special meeting on 9 May, which was attended by experts and representatives from authorities at
a federal, state, and local level from all three affected districts, it was decided that, although the
current risk of transmission was low, it could not be excluded altogether, and the following measures
were imposed on sheep farmers in the region.

Lambing must take place inside a building located outside a residential area. The doors have
to be kept shut until after the birth and after disposal of the contaminated straw.

Ewes and newborn lambs have to be kept indoors for a minimum of 14 days after the birth.

Afterbirths and stillbirths must be collected in closed sealed containers and have to be
disposed of through a disposal unit for animal carcasses. After collection of the body parts,
the containers have to be cleaned and disinfected immediately.

Contaminated straw and dung must be piled up, covered with a strong plastic cover, secured
against wind damage, and kept untouched for two years, after which it may be used as
fertiliser.

Shearing is allowed only in buildings outside a residential area. The staff must wear protective
masks. The wool has to be kept in an enclosed room until collection.

After shearing, the sheep have to be treated with a chemical bath to eliminate ticks.

Grazing areas must not be closer than 700 metres to residential or industrial areas (except for
Hallenberg, but no details are available with regard to the limit there).
These measures take into account the transmission routes and aim at preventing contact of the
population with contaminated afterbirth of sheep. It may be advisable to extend the time ewes and
lambs are kept indoors to a total of eight weeks. Humans should also avoid exposure to dust from the
fleece, which may be contaminated by excretions of ticks, which are a known host for C. burnetii.
References:
1.
2.
Smith R. Occupational exposure risk for Q fever and other zoonoses among those working on control of the foot and
mouth disease epidemic in the United Kingdom. Eurosurveillance Weekly 2001; 5: 010705.
(http://www.eurosurv.org/2001/010705.html)
Robert Koch Institut. Ein Q-Fieber Ausbruch im Hochsauerland und Nordhessen. Epidemiologisches Bulletin 2001;
26: 187-9. (http://www.rki.de/INFEKT/EPIBULL/EPI.HTM)
Reported by Wiebke Hellenbrand and Wolfgang Kiehl ([email protected]), Robert Koch-Institut, Berlin, in
cooperation with the regional health offices (Kreisgesundheitsamt des Hochsauerlandkreises,
Meschede; Kreisgesundheitsamt Waldeck-Frankenberg, Korbach); translated and adapted from
reference 2 by Birte Twisselmann ([email protected]), Eurosurveillance editorial office.
Rapid reporting EU surveillance system for meningitis W135: 2a: P1.2, 5 –
update
After an epidemic of meningococcal disease caused by Neisseria meningitidis serotype W135 among
travellers to the haj pilgrimage to Mecca in 2000, an enhanced surveillance system for serogroup
W135: 2a: P1.2, 5 meningococcal disease was set up among several European countries (1-2). Data
have been reported since September 2000, and this report summarises all confirmed cases during
the period 28 April-29 June 2001. Cases of W135: 2a: P1.2, 5 or compatible strains were reported in
France, Germany, the Netherlands, and the United Kingdom (UK). The World Health Organisation
independently reported two and four cases in Denmark and Norway, respectively, with three of these
cases having had contact with haj pilgrims (3).
In France, a strain of W135: 2a: P1.2, 5 was isolated from the blood of a 53 year old woman.
Multilocus DNA fingerprinting (MLDF) analysis showed markers of electrophoretic type (ET)-37
complex. There was no known link to haj 2001, and the patient survived. An isolate of strain W135:
NT: P1.5 was received by the French reference laboratory from the blood of a 4 month old girl. MLDF
typing showed that this strain did not belong to ET-37 complex. The patient survived, and again there
was no known link to haj 2001. Strains of serotype W135 were isolated from the blood of a 21 year
old man, an 8 month old boy, and an 83 year old man, and from the cerebrospinal fluid (CSF) of a 3
month old boy and a 20 year old woman. Serological typing is to be done on all isolates and MLDF
typing showed markers for ET-37, except in the case of the 8 month old boy. All patients survived,
and no links to haj 2001 were found.
In Germany, a case of W135: 2a: P1.2, 5 was reported in a 5 year old girl from a CSF isolate. A
connection to the haj is not known at this point. A second case of W135: 2a: P1.2, 5 was found in a 4
week old boy who died from fulminant Waterhouse-Friderichsen Syndrome. There was no known link
to the haj.
The Netherlands reported a case of W135: NT: P1.2, 5 and W135: NT: P1.7 in two boys aged 4 and 3
years, respectively. There were no known links to the haj. A case of meningococcal infection with
strain W135: 2a: P1.2, 5 was reported in a 10 month old boy, but further information about this case is
currently not available.
Six cases in the UK were confirmed as the W135: 2a: P1.2, 5 strain. Three girls aged 1–3 years all
survived, but a 34 year old man and a 2 year old boy died. They had no known links with the haj. One
case was reported in a 4 month old boy whose grandparents had contact with returning pilgrims. This
case is not known to be fatal.
References:
1.
2.
3.
Handford S, Henderson B, Ramsay M. Rapid reporting EU surveillance system for meningitis W135: 2a: P1.2, 5 –
update and summary. Eurosurveillance Weekly 2001; 5: 010607. (http://www.eurosurv.org/2001/010607.html).
Henderson B, Handford S, Ramsay M. Rapid reporting system for meningitis W135: 2a: P1.2, 5: update.
Eurosurveillance Weekly 2001; 5: 010517. (http://www.eurosurv.org/2001/010517.html).
World Health Organisation. Meningococcal Disease, serogroup W135 (update). Wkly Epidemiol Rec 2001; 76(28):
213-4. (http://www.who.int/wer/pdf/2001/wer7628.pdf)
Reported by Sarah Handford ([email protected]), Brian Henderson ([email protected]),
and Mary Ramsay ([email protected]), Public Health Laboratory Service Communicable Disease
Surveillance Centre, London, England.