Outbreaks notification of legionellosis in Spain. Años 1989 a 1998LEGIONELLA
SPAIN
Antecedents
The legionellosis is a disease that attends with a panel of pneumonía. The paradigm of the emergent diseases related to the progress is considered, because it has to do with devices and systems created by the man like the systems of refrigeration and the complex networks of water supply. Its relevance in public health comes given by: Its high lethality, specially in people of age outpost or with underlying diseases, the economic importance in the independent communities with tourism and the possibility of prevention by means of the control of the facilities that use water. Unlike other outbreaks, like which they cause to infections and nourishing poisonings or those of diseases submissive immunization, the study appear of legionellosis is little frequent, perhaps because it is a disease about which the clinical doctors nor the epidemiologic think neither. In fact, their sub detection and sub notification are a general problem and frequents
1. The objective of the present work is to
present/display the results of the investigation of outbreaks of
legionellosis in the last decade and the characteristic more excellent
epidemiologists related to his present/display ción as well as the
implied factors of risk. Material and method the analysis has become from
the two existing sources of notification. First it is the National
Network of Monitoring Epidemiologist. Through her the document of final
report is received, sent by the CCAA to the National Center of Epidemiological,
when the finishing the investigation of the outbreak and gathers demographic,
clinical variables, epidemiologists and of the made environmental study.
Second source is the provided one by the European
Group of Monitoring of Legionellosis (EWGLI). This group notifies
cases of foreign tourists that they contracted
the disease while they visited our country. For the study they have been
considered as I bring forth those groupings of cases with temporary relation
with a same lodging and between which, at least a case, was confirmed.
The information epidemiologist of the cases facilitated by the notification
countries is little. The corresponding units in the CAmake the environmental
study of the indicated hotel installation. The data talk about to decade
1989 1998 and a descriptive analysis of the variables before mentioned
has been made.
Results During the period of study have declared
55 I appear of legionellosis, 31 to Network and 24 to the EWGLI (figure
1). For their analysis, to the outbreaks in three categories in agreement
with the antecedent or atmosphere have been divided where they took place:
a) Related to trips. b) Nosocomial and cs) Communitarian. In this last
group they are had including the communitarian outbreaks that have taken
place in municipalities or related to particular houses or companies.
The notified ones with more frequency are
the related ones to trips, 36 I appear, follow the nosocomial to them with
11 and, finally, the communitarian ones with 8 I appear. In both last years
there has been an increase in the number of declared outbreaks related
to trips (in special the notified ones by EWGLI) and nosocomial (figure
2).
Only the outbreaks related to trips have clear
a seasonal distribution, with a tip of Maxima declaration during the months
of May and June.
The average of cases by outbreaks greater
for the communitarian ones (57 cases, rank between 16 and 260).
The lethality is greater for those of nosocomial
origin (17.9 %, as opposed to 4.6 % for communitarian and 10.1 % in the
related ones to trips) (table1).
To the Mediterranean communities and the Canary islands the greater number of notified outbreaks corresponds. In their majority are out breaks related to the trips and the tourism. On the other hand, seven CCAA of the zone the northwest have not notified any outbreak during the ten considered years (figure 3). In the microbiological studies, L. pneumophila serogroup 1 has been the species that with more frequency has been identified, as much in the clinical samples as of the environmental study. As well, the Pontiac subtype was most frequent (figure 4). In twelve I appear verified in the reference laboratory the similarity of the found stocks clinical and environmental.
In 42 of the 55 I appear is had information
of the made environmental study. In thirty and two obtained positive microbiological
results in the study of the infection source and in ten the results were
negative.
The microbiological findings implied to the
network of shower, water supply and faucets in 25 I appear (45 % of the
total of the declared ones) (table 2). Of the results of inspection made
them it is come off that the deficiencies in the chlorine are most frequent,
followed the deficiencies detected in the supplying network (table 3).
In 22 I appear of the 55 is had information on the adopted measures of
control, being the cleaning accompanied by hyperchlorine those that have
been taken more, specially in the outbreaks related to the trips.
Discussion the joint analysis of the two sources
of notification favours that the outbreaks related to the trips are sobrere
presented, reason why is possible to wait for greater presence of the characteristics
related to these outbreaks
in the global results. The absence of declaration
of outbreaks in some CCAA coexisting with the presence of sporadic cases
makes think, specially when they are of nosocomial origin, in a possible
sub detection and/or sub notification.
The outbreaks that were declared with more
frequency were the related ones to trips for the reasons before commented,
this increase can be attributed to the greater use of the test of detection
of antigen of Legionella in orina in many European countries
2. This disease is related to the network
of water supply and to certain systems or device that uses it and that,
in last instance, produces aerosols containing Legionella. In the results
that appear here, it is indicated to the supplying network as the main
source of infection and the failures in the chlorine as the first deficiency
related to the appearance of outbreaks. Nevertheless, it is necessary to
make a greater emphasis in improving the study of these aspects, if we
want to identify the risk mechanisms more accurately. In the last years
one has advanced much in the knowledge and development of effective measures
from the point of view of the environmental health 3 and is necessary to
continue insisting on which this disease is anticipatable when the suitable
ones are put average.
References
1, Infuso To, Hubert B, Etienne J. Underreporting
of legionnaires it disease in France: the marries for dwells activates
survei-llance. Eurosurveillance 1998;3:48-50.
2, Joseph Ca, Harrison Tg, Ilijic-Car D, Bartlett Clr. Legionnaires and Wales disease in residents of England: 1997. Communicable Disease and Public Health 1998;1:252-7.
3, General subdivision of Environmental Health.
Recommendations for the prevention and control of the legionellosis. Madrid,
General Secretariat Técnica, Ministry of Health and Consumption
1999.
Information supplied by
Centre National of Epidemiological. Institute
of Salud Carlos III.
