[Outbreak of gastroenteritis caused by Norwalk virus at a senior citizens assisted living facility in Granada, Spain].
The outbreaks of acute gastroenteritis caused by a virus are currently one of the health problems having the greatest impact on those living in senior citizen facilities. The objective of this study is that of investigating the causes of the start and contagion of an outbreak of acute gastroenteritis caused by a Norwalk-Like virus.



At a senior citizen living facility with 141 residents and 71 employees exposed, the relations between the disease in question and different independent variables: personal traits, features of location, date of onset of symptoms, clinical pattern of the disease and causal factors (food and drinking water intake). A descriptive study, a contingency table and a hypothesis ?2 test, design of cases and controls with the calculation of the unprocessed and subsequently adjusted Odds Ratio (IC 95%) were carried out using logic regression.



No significant differences were found in the personal trait and features of location variables. The attack rate among the residents was 30.1%, being 21.12% among the employees. In the adjusted Odds Ratio calculation, solely the whipped cream mousse showed causal relationship values (adjusted Odds Ratio = 4.66; IC-95% 1.15-18.91; p = 0.031). Ten patient stool samples were sent for analysis, no disease-causing bacteria having been detected, Norwalk-Like virus however having been isolated in three samples.



The whipped cream mousse having been found to possibly have been responsible for the outbreak is a first involving Norwalk virus, but this result is subject to limitations, such as the possible bias of classification due to failing to recall having eaten foods. Even so, this is an element to be taken into account in the control of acute viral gastroenteritis.
Almagro Nievas
Diego
D
Distrito Sanitario Agrupación Loja Santa Fe. alminero@cica.es
Conti Cuesta
Francisco
F
Espínola García
Esther
E
Morcillo Ródenas
Carolina
C
Núñez Sevilla
Cristina
C
Linares Torres
Juan
J
Ortiz Espinosa
Juan
J
D000208:Acute Disease; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D040561:Assisted Living Facilities; D017250:Caliciviridae Infections / Q000453:epidemiology*; D004196:Disease Outbreaks; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009663:Norwalk virus; D016017:Odds Ratio; D012737:Sex Factors; D013030:Spain / Q000453:epidemiology