Does tourism affect the long term course of COVID-19 pandemic in a country of destination? Evidence from a popular Greek island in 2020 where control measures were implemented

Greece opened its points of entry on July 1, 2020, with specific guidelines for travellers arriving by sea, air or land. The aim of this article is to examine the effect of tourism on the long term course of the Coronavirus Disease 2019 (COVID-19) pandemic during the pre-vaccination era (June to December 2020) on the popular Greek island of Crete. To achieve this, a cross-sectional serosurvey, repeated at monthly intervals, was conducted to compare the seroprevalence in Crete with seroprevalence in the mainland of Greece. Crete welcomed nearly 2,000,000 travellers during the 2020 summer season. Left-over serum samples were collected and obtained from public and private laboratories located in Greece, including the island of Crete. These samples were tested for the presence of anti-SARS-CoV-2 IgG antibodies. A total of 55,938 samples were collected, 3,785 of which originated from Crete. In Crete, the seroprevalence ranged between 0% (June 2020) and 2.58% (December 2020), while the corresponding seroprevalence in Greece was 0.19% and 10.75%, respectively. We identified 4.16 times lower seropositivity in Crete (2.58%) in comparison with the mainland of Greece (10.75%) during December 2020. Moreover, the monthly infection fatality rate (IFR) in Crete was calculated at 0.09%, compared with 0.21% in mainland Greece for December 2020. The island of Crete presented more than four times lower seroprevalence than the mainland of Greece, despite being a highly attractive tourist destination. This evidence supports the idea that tourism may not have affected the long term course of the COVID-19 pandemic in Greece. However, due to contradicting results from previous studies, further investigation is needed

Comparison of microbial colonization rates between central venous catheters and peripherally inserted central catheters

Abstract Background Central venous catheters (CVCs) and peripherally inserted central catheters (PICCs), have been widely used as intravascular devices in critically ill patients. However, they might evoke complications, such as catheter colonization that has been considered as predisposing factor for central line-associated bloodstream infections (CLABSIs). Although numerous studies have compared the risk of bloodstream infections between PICCs and CVCs, comparative studies on their colonization rates are limited. Objectives The episodes of catheter colonization in critically ill patients with CVCs or PICCs were retrospectively analysed during a two-year period in a Greek tertiary care hospital and colonization rates, microbial profiles and antimicrobial susceptibility patterns were compared. Methods Clinical and laboratory data of consecutive hospitalized critically-ill patients who underwent PICC and CVC placement between May 2017–May 2019 were analysed. All catheters were examined by the semiquantitative culture technique for bacterial pathogens, either as a routine process after catheter removal or after suspicion of infection. Species identification and antimicrobial resistance patterns were determined by the Vitek2 automated system. Results During the survey period a total of 122/1187 (10.28%) catheter colonization cases were identified among CVCs and 19/639 (2.97%) cases among PICCs (p = 0.001). The colonization rate was 12.48/1000 catheter-days for the CVC group and 1.71/1000 catheter-days for the PICC group (p < 0.001). The colonization rate per 1000 catheter-days due to multidrug-resistant organisms (MDROs) was 3.85 in all study cases, 7.26 (71/122) in the CVC group and 0.63 (7/19) in the PICC group (p < 0.001). Within the CVC group, the most common microorganism isolated was MDR Acinetobacter baumannii (n = 38, 31.1%) followed by MDR Klebsiella pneumoniae (n = 20, 16.4%). In the PICC group, the predominant microorganism isolated was Candida spp. (n = 5, 23.8%) followed by MDR K. pneumoniae and MDR A. baumannii in equal numbers (n = 3, 14.2%). Conclusion PICC lines were associated with significantly lower colonization rates comparing to the CVC ones. In addition, patterns of microbial colonization revealed a trend over the predominance of MDR gram-negatives in CVCs suggesting that PICCs might be a safer alternative for prolonged inpatient intravascular access. Prevention programs directed by local microbial ecology may diminish catheter colonization rates and CLABSIs

Myasthenia gravis: a pupillometric study

The transformation rules and field equations of d = 11 supergravity are given in a form which is manifestly covariant under local SU(8) transformations. In this formulation the SO(1, 10) local Lorentz group is replaced by SO(1, 3) × SU(8). The spinless fields are described by covariant quantities which constitute the Image representations of E7(+7)