key: cord-0843298-sg4lfsov
authors: Peytremann, Arnaud; Senn, Prof Nicolas; Mueller, Dr Yolanda
title: Infection prevention and control measures in practices of the Swiss sentinel network during seasonal influenza epidemics
date: 2020-09-03
journal: J Hosp Infect
DOI: 10.1016/j.jhin.2020.08.026
sha: 6ddb64fb39759abb70395016153d3421129f5f7d
doc_id: 843298
cord_uid: sg4lfsov

BACKGROUND: There is limited data about healthcare influenza transmission in the context of primary care practices, despite the fact that a significant proportion of the population consults their primary care physician for an influenza-like illness every year. AIM: We aimed to describe the use of influenza prevention and control methods in private practices of the Swiss sentinel network. METHODS: This online cross-sectional survey collected data about infection prevention and control measures in the 166 private practices of the Swiss sentinel surveillance network during the 2018-19 influenza season. Questions pertained to the practice setting, infection prevention and control recommendations, influenza vaccination of the physicians and their employees, adhesion to hand hygiene, and mask wearing. FINDINGS: Among the 122 practices that answered (response rate 73.5%), 90.2% of the responding physicians were themselves vaccinated, and 46.7% (56/120) estimated their staff vaccination coverage to be above 60%, although it was offered to employees in all practices. Most practices (68, 55.7%) had no specific recommendations for their staff concerning mask wearing. Most physicians reported washing or disinfecting their hands before examining a patient (91, 74.6%), after examination (110, 90.2%) and before a medical procedure (112, 91.8%). However, this rate decreased regarding arrival at the practice (78, 63.9%) or leaving it (83, 68.0%). CONCLUSION: Most physicians of the Sentinella network are themselves vaccinated. However, the vaccination rates among employees are low, despite vaccine availability. Hand hygiene measures were also sub-optimal. These results warrant further efforts to implement infection prevention and control measures in the ambulatory setting.

Influenza is a very common disease, affecting a significant proportion of the population every year, and while mild in most cases, it can be fatal for vulnerable groups. The roles of different transmission settings are largely unknown [1] . Schools and day care centres probably play an important role, as do hospitals for vulnerable groups [2] . However, the role of primary care (PC) sector in the transmission chain is unclear, as most data about healthcare associated infections are based on inpatient studies rather than the ambulatory sector.

Primary care physicians (PCP) play key roles during the seasonal influenza epidemics, first by vaccinating the population in particular vulnerable groups and second, by managing the vast majority of influenza cases. For example, in Switzerland it was estimated that during the 2018-19 season 2.5% of the Swiss population consulted a PCP for an influenza-like-illness (ILI), defined as a history of fever (>38°C) and presence of either sore throat or cough [3] .

Finally, some PCP participate in the Swiss influenza surveillance system (Sentinella), on which the Federal Office of Public Health (FOPH) relies to officially declare each influenza epidemic season (defined as an influenza incidence above 68/100 000 population for the past season) [3] . This system is composed of PCP all over Switzerland that take part voluntarily in epidemiological disease surveillance, by sending ILI cases data to FOPH and collecting swabs and sending them for analysis to the National Reference Centre for Influenza (NRCI) [4] .

These practices do not receiving any additional training nor extra material (apart from swabs) for infection prevention and control, as they are meant to be representative of Swiss primary care practices. Many countries have such a sentinel approach to monitor the J o u r n a l P r e -p r o o f influenza epidemic, which is complementary to newer approaches based on voluntary selfreporting by the population via connected tools [5] .

The main challenge with influenza infectivity is that people begin to be infectious 24 hours prior to the appearance of symptoms. Therefore, infection control targeting only symptomatic individuals, for example mask wearing in case of symptoms, is unable to prevent all of influenza transmission. In addition, transmission occurs via different routes, mainly by direct contact or droplets, but also via aerosols [6] . Furthermore, its clinical diagnosis is not reliable [7] . Concerning healthcare associated infection, a study in Canada showed that 17.3% of hospital-admitted patients with a positive influenza test had acquired their influenza infection in a healthcare facility [8] .

Because of their daily interaction with sick people in general, and especially those with influenza, HCW are more at risk to be infected [1] , but also to transmit influenza virus, especially as they can be asymptomatic carriers [9] [10] [11] [12] [13] . For example, 23% of HCW in four Scottish hospitals had probably acquired an asymptomatic influenza infection during the season, defined as an increase of at least 50% in antibody titres, during the 1993/1994 epidemic [14] . A systematic review published in 2019 showed that there was very little data about interventions to reduce influenza transmission in primary care practices; most recommendations made in PC are indeed extrapolated from studies done in inpatient settings [15] . A recent survey in Netherlands showed that there was no proper data for healthcare acquired infection treated by PCP and that some physicians believed they were mainly related to hospital and not outpatient settings [16, 17] .

Even if vaccine effectiveness is difficult to assess, vaccination is still one of the only proven prevention methods against influenza [18, 19] , leading to a lower rate of influenza infection in vaccinated HCW [9] . A study in 2016 showed that the vaccination rate among HCW was highly variable and as low as around 40% in Europe, compared to 77% in USA [20] , while a recent Italian study found a vaccination rate of 30% among primary care physicians [21] . In Switzerland, that rate was estimated around 16% for the years 2012 and 2017 [22] .

General infection control measures, such as basic hand-hygiene, either with soap and water or with alcohol-based solution, are other recognized ways to reduce transmission [23, 24] .

We conducted a cross-sectional survey among the 166 primary care practices of the Swiss sentinel network (Sentinella) between March 12 th and April 25 th , 2019. Sentinella is a network of general practitioners and paediatricians from all over Switzerland, put in place by the FOPH to monitor transmissible diseases in the country, mainly influenza. These private practices take part voluntarily in the collection of data.

In each Sentinella practice, a single physician is identified as responder for the sentinel network. The number of practices can vary depending on how many practices choose to participate, but at the time of our study it was 166. In 2019, 37.5% of Sentinella physicians were women, which is comparable to the proportion reported by the Swiss Physicians Federation (Foederatio Medicorum Helveticorum -FMH) [33] .

The topics addressed by the questionnaire were the following: J o u r n a l P r e -p r o o f -10 -Physician participation in the survey was voluntary and no specific written consent was required. The FOPH manages the Sentinella system and guarantees participants' anonymity by using a unique code for each practice. The investigators had no access to identifying data.

As the data contained no patient specific information, it was not under the scope of the Human Health Research Law and did not require ethical review.

Results:

Out of the 166 member practices of the Sentinella network, 133 questionnaires were received (80.12%), of which 15 were paper-based. After removing duplicates and incomplete forms and including non-referenced identifier that were considered data entry errors and accepted as valid, we had in the end 122 valid responses (73.5%, figure 1 ).

Most practices included a generalist physician (88.5%) and/or a paediatrician (13.1%). Only a small number of physicians were from other specialties. The median number of physicians per practice was two, and they were consulting a median of 7.5 half-days per week. There were four additional staff on average, mainly medical assistants, administrative secretaries, or cleaners. The median number of consultation rooms was three with one waiting room.

( Table I ). In most practices, patients with influenza symptoms were asked to wait in a separate room (N=80, 65.6%); in others there was no separation from other patients (N=8, 6.6%) or we got no answer (N=34, 27.9%). (Table II Vaccination was offered free of charge to employees in all practices and most physicians reported knowing (105, 86.1%) who among their staff was vaccinated. They estimated their staff vaccination coverage to be above 60%, respectively above 80%, in 46.7% (56/120) and 29 .2% (35/120) ( Table II) .

Most physicians reported having washed or disinfected their hands before examining a patient (91, 74.6%), after examination (110, 90.2%) and before a medical procedure (112, 91.8%). However, this rate was lower on arrival at the practice (78, 63.9%) or when leaving it (83, 68.0%). (Figure 2: Hand Hygiene) .

Almost all practices provided access to hand sanitizer for their staff (121, 99.2%).

Nevertheless, when it came to providing disinfectant to patients, this rate decreased, with some providing it only during the influenza season (13, 10.7%), or not at all (45, 37,2%) ( Table II) .

Masks for self-protection were rarely made available to patients (63, 52.5%), with 28.3% In this survey, some infection prevention and control measures are already implemented in private practices of the Swiss sentinel network, yet there is room for improvement. For example, physicians' reported vaccination coverage was excellent but coverage in the other staff was lower. Adherence to hand hygiene rules was good after examining a patient and before medical procedures, but sub-optimal at other time-points. Most of the practices were cleaning and ventilating their consultation and waiting rooms frequently, which may contribute to a reduction in influenza transmission. Patient isolation was rarely feasible when there is only one waiting room. There were often no clear recommendations about mask wearing, whether for staff or for patients. In general, Swiss Primary Care physicians are aware of the rules for hand-hygiene edited by the WHO (Clean your hands campaign), and also the national recommendation about vaccination [32] .

Our study has some limitations. First, the survey was based on self-declaration, which leads to inevitable desirability bias. Second, we did not request the exact rate of vaccination coverage amongst the staff, but only the rate estimated by the physician. However, assuming that the reporting physician follows the health of his staff, the given approximation is probably close to the reality. Third, regarding hand hygiene, despite a good reported availability of hand disinfectants, we were not able to observe direct use by the staff or physicians, and we only have data about the physicians and not their staff.

The influenza vaccination coverage among primary care (PC) staff was lower than the usual 75% coverage recommended by WHO [20, 21] . Nevertheless, it was still higher than most J o u r n a l P r e -p r o o f rates found in the health sector around the world [20] . In comparison, an Italian study showed a vaccination rate of 22% among Medical Residents [11] , but another French survey showed a rate of 78% for influenza vaccination among GPs [35] . This year in Switzerland, the estimated vaccination rate for HCW was 23% [3] . A positive point is that the vaccination was offered in every participating practice, and that physicians themselves are vaccinated. They could act as role models to improve the vaccination among their staff, as it has been shown to be effective [20] . A systematic review demonstrated that HCW vaccination was associated with a lower risk of ILI for themselves [36] and that it drastically lowers the infection risk for patients [19] .

The hand hygiene questions revealed substantial variation, as in certain conditions proper hand hygiene was respected 90% of the time, whereas in the absence of direct contact with patients, this percentage was much lower. This is unsurprising, however, since little attention has been given to hand hygiene in the primary care sector. The "five moments for hand hygiene" advocated by WHO were developed for the hospital setting and may require some adaptation before implementation in the primary care context [23] , considering that hand-hygiene, if properly done, can lower influenza transmission [24] . Many physicians use soap-based cleaning almost as frequently as alcohol-based hand rub, which was similar to results of a Dutch study [16] . The hand hygiene could be optimised by campaign from the FOPH or specific trainings to private practices to encourage them.

In addition, according to the results of our survey, there were often no clear recommendations given by the physicians in the participating practices about the use of J o u r n a l P r e -p r o o f protective masks, be it for patients or staff. Despite the fact that mask wearing is recommended by most health authorities [7] , some reviews showed that the protective effect of using mask was not proven against influenza [1, 37] , and another study in 2019 proved that there was no difference between high-filtration or normal medical masks [38] . In our study we did not collect data on the utilization rate of masks by the working personnel.

We nevertheless have data regarding the availability of masks for the staff for their personal use. We hope that physicians will be more aware of their role as implementers of protectivemask wearing during seasonal respiratory epidemics after our study.

In terms of generalizability, Sentinella practices may not be fully representative of Swiss family practices as they voluntarily participate in influenza surveillance and may therefore be more concerned about infection prevention and control. However, the practices in our survey are comparable to Swiss primary care practices, in terms of practice size and activity [33, 39] . In addition, all Swiss regions are represented in the network. Although adhesion to prevention and control measures is likely to be better in Sentinella practices compared to the average Swiss practice, the weaknesses in prevention and control habits identified in our survey can still be used to develop recommendations better targeted to this context. More data is definitely needed in the field of infection prevention and control in primary care practices, as well as more evidence regarding the impact of specific measures and interventions to increase their implementation. In particular, hand hygiene or room ventilation should be recommended clearly, and intensely promoted at practice level. In addition, specific studies assessing the effectiveness of staff vaccination, or mask wearing on influenza transmission in PCP are required. As the first study of this kind, the data collected here are very valuable, as they will pave the way for future, more comprehensive studies. In particular, it would be very interesting to repeat the survey during the COVID-19 pandemic, to capture changes that took place in PCP. 

The authors declare no conflict of interest in this study.

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We acknowledge the contributions of Damir Perisa and Raphael Rytz from the Federal Office of Public Health in communicating the study information to the Sentinella members and transmitting the data to the investigators.We thank all the physicians and staff of the Sentinella network for collecting and reporting the data.We thank also Dr Christiane Petignat, Cantonal Unit for Hospital Prevention and Control of Infection, for her advice on the questionnaire. J o u r n a l P r e -p r o o f