Infezioni correlate alla pratica assistenziale in strutture residenziali per anziani in Veneto: prevalenza, colonizzazione da MRSA e proposta di un programma di controllo che include un sistema di allerta precoce per epidemie

During the past few decades demographic, social and medical care factors have resulted in a remarkable increase in the institutionalized elderly population in Italy. These persons present, because of physiological features and of the particular medical assistance they receive, very high health risks, including a risk of developing infections. Risk of infection in long term care facilities for the elderly is considered to be at the same level as in regular hospitals. In Italy this issue is still not well known, however recent investigations highlighted remarkable difficulties in the application of control measures, which represents a serious health problem since in this specific context even outbreaks of limited dimension can have a significant impact on the health of the patients. The general purpose of the project is to contribute to the improvement of aid and sanitary care in residential facilities for the elderly through a specific infection control program. Considering the lack of knowledge of the problem in Italy, we first tried to quantify the issue through a prevalence investigation in a few facilities of Veneto. The investigation used a detection form appositely created that bases infectious disease diagnoses on symptomatic criteria and that also includes a collection of individual information in order to identify possible personal risk factors. Starting from the infection risks detected during our prevalence investigation we created guidelines for infection control in long term healthcare facilities for elderly people, in collaboration with experts in infectious disease control measures. Considering that the appearance of multidrug resistant strain bacteria is currently one of the emerging problems in health care facilities we also arranged to verify MRSA colonization in a part of the population included in the investigation. Finally the case definitions of the prevalence surveys were proposed to be used to create a syndromic epidemic early warning system manageable by non medical staff through the support of simple software which highlights anomalous epidemiological conditions (aberrations). The research activities took place during the first two years at the Regional Epidemiological Centre of Veneto (SER Servizio Epidemiologico Regione Veneto), in Castelfranco Veneto, Italy, and during the third year at the Epidemic Alert and Response Unity of the Regional Office for the Americas (AMRO) of the World Health Organization (WHO), based in Washington, DC (USA). Activities regarded four different issues: 1) Prevalence of infections in long term care facilities for elderly people Initially the activity focused on the creation of an infectious disease detection tool that consisted of an intake form including two sections. The first section helps to define the institutionalized guests by collecting individual demographic and sanitary information, which highlight individual potential risk factors. The second section of the form includes the detection of infections. Taking into account the limitations in long term care facilities for the elderly, such as the difficulty of obtaining laboratory diagnoses and the lack of medical staff, we decided to use symptomatic criteria (easily identifiable signs and symptoms) for case definitions without the need of laboratory confirmations. These definitions were developed for this specific target population during a consensus conference at the beginning of the 1990s; criteria were subsequently approved by the main medical organizations dealing with infection control and are currently considered the gold standard in prevalence investigations of infections in long term care facilities for the elderly. Once the detection tool was defined we validated it through some pilot studies before using it for investigations in three long term care facilities for the elderly in Veneto, involving 340 patients. During the first investigation, infections were diagnosed in 52 patients for a prevalence rate of 15.3%. Half of the cases were respiratory infections; skin and urinary infections were also frequent; and there was a significant association between infections and patient disability level. A second investigation was developed using the same case detection tool in two additional residential facilities for elderly people of Veneto, involving a total of 570 individuals. The target population presented the same demographic characteristics and medical conditions as in the first survey. There were 64 cases of infections detected in 63 patients, prevalence rate was 11.1%. The most frequent infections involved the lower respiratory tract, urinary tract and skin/soft tissues. Prevalence was higher in people hospitalized at least one time during the last year; risk was also related to number of systemic antibiotic treatments received during last 12 months. 2) Prevalence of MRSA colonization in long term care facilities for elderly people The only relevant modification in the income form used during the second investigation was the record of all antibiotic treatments received by the guests in the twelve previous months. Modification was related to the decision to combine this second prevalence investigation with an evaluation of state of Methicillin Resistant Staphylococcus aureus (MRSA) colonization of the nasal mucosa. MRSA is a major public health challenge in health care facilities and an important cause of death in hospitalized individuals. The presence of this agent has also been recently documented at nursing homes; currently there is a lack of investigation in Italy about this issue and our study, with 551 of 570 patients, represents the most important analysis at the national level. We used the individual information registered in the income form to analyze the association between MRSA colonization and individual risk factors, in particular antibiotic administration. 43 subjects colonized with MRSA have been identified, prevalence was 7.8 %. All colonized individuals resulted to be fluorochinolone-resistant, nine were also resistant to eritromicina, five to clindamicina and one to trimetropin-sulfametossazolo Of the fifteen wards in the two nursing homes only two were MRSA free. Recent investigations obtained similar results regarding fluorochinolone resistance. This means there is the need for a prudent use of antibiotic treatment in the case of this elderly population, especially for this class of drugs. 3) Guidelines for infection control in long tem care facilities The project also included specific training for the staff giving assistance to the elderly population hosted in the nursing homes. The manual considers epidemiological aspects of infections and specific recommendations for a relevant control program, including basic standard precautions and additional transmission based precautions for patients with documented or suspected contagious pathogens. Specific short intensive courses were held during the time of the project. 4) Syndromic Surveillance The last part of the activity took place at the Regional Office of the Americas of the World Health Organization, specifically at the Epidemic Alert and Response Team (EAR). Activity was focused on recollecting further documentation on long term care facility infection control and to develop skills on syndromic surveillance. The EAR team provided support in developing and implementing a Mass Gathering Surveillance System (MGSS) during an important international event which affected countries with limited surveillance resources. An international event, such as this, which attracts a high number of visitors from around the world and occurs in a country facing diagnostic difficulties, can be compared to long term care facilities for the elderly. In both cases detection of infectious diseases is difficult and target populations present a potentially very high risk for infection. Syndromic surveillance is an array of methods aimed at early detection of epidemics, monitoring syndromes that might represent early stages of epidemics. Clearly such a system does not identify subjects with confirmed infections; nevertheless it creates a useful informative system that with the support of statistical softwares identifies situations that need further investigation. This can prevent potential epidemics in a context with diagnostic difficulties isuch as in long term care facilities. The proposal is to apply a syndromic surveillance system in long term care facilities for a few specific syndromes, with the goal of identifying suspected cases of infections using the same case definitions included in the prevalence survey tool. The system should be managed, after adequate training, by the internal staff and would consist in periodic recording of cases following syndromic case definitions and in periodical statistical elaborations of recorded data through software able to detect significant increases of potential pathological conditions that need to be investigated.