As of 9 June 2020, 1 444 710 cases of COVID-19 were reported by EU/EEA countries and the UK, including 169 207 deaths . Detailed information on the COVID-19 cases reported so far are available on a dedicated ECDC webpage .
More up-to-date disease background information is available online (ECDC , WHO ) and from the latest ECDC Rapid Risk Assessment .
Infection prevention and control (IPC) practices are of critical importance in protecting the function of healthcare services at all levels and mitigating the impact on vulnerable populations. Although the management of possible COVID-19 cases is usually guided by national policies for specific healthcare facilities, community transmission is currently widespread in most EU/EEA countries and the UK, therefore primary healthcare providers in the community such as GPs, dentists and pharmacists are at risk of being exposed to COVID-19.
In most instances, coronaviruses, including SARS-CoV-2, are transmitted from person to person through large respiratory droplets produced during normal conversation or when coughing and sneezing, either by inhalation or deposition on mucosal surfaces. Other routes implicated in transmission of coronaviruses include contact with contaminated fomites (e.g. frequently touched surfaces) and inhalation of aerosols produced during aerosolgenerating procedures (AGPs). Viral RNA has also been detected in blood specimens, albeit rarely, but there is no evidence of transmission through contact with blood . The relative role of droplet, fomite and aerosol transmission for SARS-CoV-2, and the transmissibility of the virus at different stages of the disease remain partly unclear.
There is increasing evidence that persons with mild or no symptoms contribute to the spread of COVID-19 [5,6].
Asymptomatic infection at time of laboratory confirmation has been reported from many settings [7-10]. During a systematic screening of 143 393 residents and 139 409 healthcare workers in all Belgium long-term care facilities (as of 19 May 2020), 75% of 8 780 RT-PCR positives were asymptomatic at the time of nasopharyngeal sampling . Some of these cases developed some symptoms at a later stage of infection, however, the proportion of cases that will develop symptoms is not yet fully understood [12,13]. There are also reports of cases remaining asymptomatic but with detectable viral RNA shedding throughout the whole duration of laboratory monitoring. In a recent review, the proportion of positive cases that remained asymptomatic was estimated at 16%, with a range from 6 to 41% . Furthermore, pre-symptomatic transmission has been reported in cases where exposure occurred 1–3 days before the source patient developed symptoms . The proportion of presymptomatic transmission out of all transmissions has been inferred through mathematical modelling as being between 48% and 62%, in the presence of control measures . Because of the importance of a- and presymptomatic transmission of COVID-19, WHO recommended that in areas with community transmission of COVID19, all healthcare workers, including community health workers and caregivers, who work in clinical areas should continuously wear a medical mask during their routine activities throughout the entire shift .
Furthermore, with the exception of AGPs, it is unclear whether facial filtering piece (FFP) respirators (class 2 or 3) provide better protection than medical face masks against other coronaviruses and other respiratory viruses such as influenza [17,18]. Therefore, a rational approach to the use of PPE in case of widespread community transmission and shortages of PPE, necessitates that FFP2/3 respirators are prioritised for care activities with a higher perceived risk of transmission, such as AGPs.