COVID-19 impact on EuroTravNet infectious diseases sentinel surveillance in Europe.

BACKGROUND: The COVID-19 pandemic resulted in a sharp decline of post-travel patient encounters at the European sentinel surveillance network (EuroTravNet) of travellers' health. We report on the impact of COVID-19 on travel-related infectious diseases as recorded by EuroTravNet clinics. METHODS: Travelers who presented between January 1, 2019 and September 30, 2021 were included. Comparisons were made between the pre-pandemic period (14 months from January 1, 2019 to February 29, 2020); and the pandemic period (19 months from March 1, 2020 to September 30, 2021). RESULTS: Of the 15,124 visits to the network during the 33-month observation period, 10,941 (72%) were during the pre-pandemic period, and 4183 (28%) during the pandemic period. Average monthly visits declined from 782/month (pre-COVID-19 era) to 220/month (COVID-19 pandemic era). Among non-migrants, the top-10 countries of exposure changed after onset of the COVID-19 pandemic; destinations such as Italy and Austria, where COVID-19 exposure peaked in the first months, replaced typical travel destinations in Asia (Thailand, Indonesia, India). There was a small decline in migrant patients reported, with little change in the top countries of exposure (Bolivia, Mali). The three top diagnoses with the largest overall decreases in relative frequency were acute gastroenteritis (-5.3%), rabies post-exposure prophylaxis (-2.8%), and dengue (-2.6%). Apart from COVID-19 (which rose from 0.1% to 12.7%), the three top diagnoses with the largest overall relative frequency increase were schistosomiasis (+4.9%), strongyloidiasis (+2.7%), and latent tuberculosis (+2.4%). CONCLUSIONS: A marked COVID-19 pandemic-induced decline in global travel activities is reflected in reduced travel-related infectious diseases sentinel surveillance reporting.

Analysis of Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA) Parameters in Young Adults after SARS-CoV-2 Infection (COVID-19) Compared with Healthy Young Controls.

PURPOSE: To compare retinal changes in young adults with previous SARS-CoV-2 infection with healthy young controls using optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). METHODS: This prospective single-center study was conducted at the University Hospital of Zurich, Zurich, Switzerland. Participants were imaged from May to November 2021 using the SOLIX device (Visionix International SAS, Pont-de-l'Arche, France). We performed 12 mm × 12 mm, 6.4 mm × 6.4 mm, 6 mm × 6 mm and 3 mm × 3 mm OCT and OCTA scans, as well as fundus photography of each participant's eyes. RESULTS: In total, 466 participants were imaged. Of these, 233 were healthy controls with negative RT-PCR tests for SARS-CoV-2, 168 were young adults who had a SARS-CoV-2 infection at least 180 days previously, 19 were participants who had a SARS-CoV-2 infection < 180 days previously, and 46 were participants with asymptomatic SARS-CoV-2 infection (i.e., serologically positive but with no symptoms). Compared with healthy controls, statistically significant differences were found for OCTA recordings of the optic disc for the whole image (WI) and WI capillary vessel density, with both being higher in the SARS-CoV-2 group. CONCLUSION: Statistically significant results were only observed for selected variables, and in parts, only unilaterally, with relatively large p values (p = 0.02-0.03). Thus, we did not interpret these as clinically significant, leading to the conclusion that young and otherwise healthy individuals (mainly men) seem to recover from mild COVID-19 infections with no ophthalmological residues.

Persistence, prevalence, and polymorphism of sequelae after COVID-19 in unvaccinated, young adults of the Swiss Armed Forces: a longitudinal, cohort study (LoCoMo).

BACKGROUND: Persistent COVID-19 sequelae could have global, public health ramifications. We therefore aimed to describe sequelae presenting more than 180 days after COVID-19-focussing on several organ systems, general health, and laboratory parameters-in non-hospitalised, unvaccinated, young adults. METHODS: We did a longitudinal cohort study of all army bases in Switzerland. Eligible participants were personnel of the Swiss Armed Forces (SAF) who were aged 18-30 years with a positive or negative RT-PCR test for SARS-CoV-2 during their service between March 1, 2020, and Dec 31, 2020. Exclusion criteria were unwillingness to participate in testing. Females or men with a known reproductive anomaly were excluded from the optional component of male fertility testing. COVID-19 was defined as a positive diagnostic RT-PCR test result for SARS-CoV-2 with concurrent symptoms compatible with COVID-19. Participants were subdivided into four groups: control group (ie, serologically negative), asymptomatic infection group (ie, serologically positive but with no symptoms), non-recent COVID-19 group (>180 days since positive PCR test), and recent COVID-19 group (≤180 days since positive PCR test). Outcomes of interest were part of a comprehensive, intensive test battery that was administered during a single day. The test battery quantified the effect of SARS-CoV-2 infection on cardiovascular, pulmonary, neurological, renal, ophthalmological, male reproductive, psychological, general health, and laboratory parameters. This study was registered with ClinicalTrials.gov, number NCT04942249. FINDINGS: Between May 20, 2021, and Nov 26, 2021, we enrolled 501 participants. 29 (6%) of 501 were female and 464 (93%) were male, and the median age was 21 years (IQR 21-23). Eight (2%) of 501 had incomplete data and were not included into the study groups. 177 participants had previous COVID-19 that was more than 180 days (mean 340 days) since diagnosis (ie, the non-recent COVID-19 group) compared with 251 serologically negative individuals (ie, the control group). We included 19 participants in the recent COVID-19 group and 46 in the asymptomatic infection group. We found a significant trend towards metabolic disorders in participants of the non-recent COVID-19 group compared with those in the control group: higher BMI (median 24·0 kg/m2 [IQR 22·0-25·8] vs 23·2 kg/m2 [27·1-25·0]; p=0·035), lower aerobic threshold (39% [36-43] vs 41% [37-46]; p=0·012), and higher blood cholesterol (4·2 µM [3·7-4·7] vs 3·9 µM [3·5-4·5]; p<0·0001) and LDL concentrations (2·4 µM [1·9-2·9] vs 2·2 µM [1·7-2·7]; p=0·001). The only significant psychosocial difference was found in the results of the Chalder Fatigue scale with the non-recent COVID-19 group reporting higher fatigue scores than the control group (median 12 points [IQR 11-15] vs 11 [9-14]; p=0·027). No significant differences in other psychosocial questionnaire scores, ophthalmological outcomes, and sperm quality or motility were reported between the control group and non-recent COVID-19 group. INTERPRETATION: Young, previously healthy, individuals largely recover from SARS-CoV-2 infection. However, the constellation of higher BMI, dyslipidaemia, and lower physical endurance 180 days after COVID-19 is suggestive of a higher risk of developing metabolic disorders and possible cardiovascular complications. These findings will guide future investigations and follow-up management. FUNDING: Swiss Armed Forces.

Mobile apps for travel medicine and ethical considerations: A systematic review.

BACKGROUND: The advent of mobile applications for health and medicine will revolutionize travel medicine. Despite their many benefits, such as access to real-time data, mobile apps for travel medicine are accompanied by many ethical issues, including questions about security and privacy. METHODS: A systematic literature review as conducted following PRISMA guidelines. Database screening yielded 1795 results and seven papers satisfied the criteria for inclusion. Through a mix of inductive and deductive data extraction, this systematic review examined both the benefits and challenges, as well as ethical considerations, of mobile apps for travel medicine. RESULTS: Ethical considerations were discussed with varying depth across the included articles, with privacy and data protection mentioned most frequently, highlighting concerns over sensitive information and a lack of guidelines in the digital sphere. Additionally, technical concerns about data quality and bias were predominant issues for researchers and developers alike. Some ethical issues were not discussed at all, including equity, and user involvement. CONCLUSION: This paper highlights the scarcity of discussion around ethical issues. Both researchers and developers need to better integrate ethical reflection at each step of the development and use of health apps. More effective oversight mechanisms and clearer ethical guidance are needed to guide the stakeholders in this endeavour.

Assessment and management of asymptomatic COVID-19 infection: A systematic review.

BACKGROUND: COVID-19 can be asymptomatic in a substantial proportion of patients. The assessment and management of these patients constitute a key element to stop dissemination. AIM: To describe the assessment and treatment of asymptomatic infection in patients with a confirmed diagnosis of COVID-19. METHODS: We searched five databases and search engines for preprints/preproofs, up to August 22, 2020. We included cohort, cross-sectional, and case series studies, reporting the assessment and management of asymptomatic individuals. We extracted data on total discharges with negative PCR, length of hospitalization, treatment, and number of patients who remained asymptomatic. A random-effects model with inverse variance method was used to calculate the pooled prevalence. RESULTS: 41 studies (nine cross-sectional studies, five retrospective studies and 27 reports/case series; 647 asymptomatic individuals), were included, of which 47% were male (233/501). The age of patients was between 1month and 73 years. In patients who became symptomatic, length of hospitalization mean was 13.6 days (SD 6.4). Studies used lopinavir/ritonavir, hydroxychloroquine plus ritonavir/lopinavir, hydroxychloroquine with and without azithromycin, ribavirin plus interferon and interferon alfa. The proportion of individuals who remained asymptomatic was 91% (463/588 patients; 95%CI: 78.3%-98.7%); and asymptomatic individuals discharged with negative PCR was 86% (102/124 individuals; 95%CI: 58.4%-100%). CONCLUSIONS: There is no standard treatment for asymptomatic COVID-19 individuals. There are no studies of adequate design to make this decision. It has been shown that most asymptomatic individuals who were followed have recovered, but this cannot be attributed to standard treatment.

COVID-19 sequelae in adults aged less than 50 years: A systematic review.

BACKGROUND: There is emerging evidence of long-term sequelae in a considerable proportion of COVID-19 patients after recovery and the spectrum and severity of such sequelae should be systematically reviewed. This review aims to evaluate the available evidence of all intermediate and long-term COVID-19 sequelae affecting formerly healthy adults. METHODS: A systematic literature search of Embase, WHO, Scopus, Pubmed, Litcovid, bioRxiv and medRxiv was conducted with a cutoff date of the 17th September 2020 according to PRISMA guidelines and registered in PROSPERO (CRD42020208725). Search terms included "COVID-19", "coronavirus disease 2019", "SARS-CoV-2", "sequelae" and "consequence*". Publications on adult participants, with a confirmed SARS-CoV-2 infection were included. Elderly (>50 years old) and children (<18 years old) were excluded. Bias assessment was performed using a modified Newcastle-Ottawa Scale. RESULTS: A total of 31 papers were included. Study types included prospective and retrospective cohort studies, cross-sectional studies and case reports. Sequelae persistence since infection spanned 14 days to three months. Sequelae included persistent fatigue (39-73% of assessed persons), breathlessness (39-74%), decrease in quality of life (44-69%), impaired pulmonary function, abnormal CT findings including pulmonary fibrosis (39-83%), evidence of peri-/perimyo-/myocarditis (3-26%), changes in microstructural and functional brain integrity with persistent neurological symptoms (55%), increased incidence of psychiatric diagnoses (5.8% versus 2.5-3.4% in controls), incomplete recovery of olfactory and gustatory dysfunction (33-36% of evaluated persons). CONCLUSIONS: A variety of organ systems are affected by COVID-19 in the intermediate and longer-term after recovery. Main sequelae include post-infectious fatigue, persistent reduced lung function and carditis. Careful follow-up post COVID 19 is indicated to assess and mitigate possible organ damage and preserve life quality.

Reprint of: Air travel and COVID-19 prevention in the pandemic and peri-pandemic period: A narrative review.

Air travel during the COVID-19 pandemic is challenging for travellers, airlines, airports, health authorities, and governments. We reviewed multiple aspects of COVID peri-pandemic air travel, including data on traveller numbers, peri-flight prevention, and testing recommendations and in-flight SARS-CoV-2 transmission, photo-epidemiology of mask use, the pausing of air travel to mass gathering events, and quarantine measures and their effectiveness. Flights are reduced by 43% compared to 2019. Hygiene measures, mask use, and distancing are effective, while temperature screening has been shown to be unreliable. Although the risk of in-flight transmission is considered to be very low, estimated at one case per 27 million travellers, confirmed in-flight cases have been published. Some models exist and predict minimal risk but fail to consider human behavior and airline procedures variations. Despite aircraft high-efficiency filtering, there is some evidence that passengers within two rows of an index case are at higher risk. Air travel to mass gatherings should be avoided. Antigen testing is useful but impaired by time lag to results. Widespread application of solutions such as saliva-based, rapid testing or even detection with the help of "sniffer dogs" might be the way forward. The "traffic light system" for traveling, recently introduced by the Council of the European Union is a first step towards normalization of air travel. Quarantine of travellers may delay introduction or re-introduction of the virus, or may delay the peak of transmission, but the effect is small and there is limited evidence. New protocols detailing on-arrival, rapid testing and tracing are indicated to ensure that restricted movement is pragmatically implemented. Guidelines from airlines are non-transparent. Most airlines disinfect their flights and enforce wearing masks and social distancing to a certain degree. A layered approach of non-pharmaceutical interventions, screening and testing procedures, implementation and adherence to distancing, hygiene measures and mask use at airports, in-flight and throughout the entire journey together with pragmatic post-flight testing and tracing are all effective measures that can be implemented. Ongoing research and systematic review are indicated to provide evidence on the utility of preventive measures and to help answer the question "is it safe to fly?".

COVID-19 in the least developed, fragile, and conflict-affected countries - How can the most vulnerable be protected?

The relentless spread of coronavirus disease 2019 (COVID-19) and its penetration into the least developed, fragile, and conflict-affected countries (LDFCAC) is a certainty. Expansion of the pandemic will be expedited by factors such as an abundance of at-risk populations, inadequate COVID-19 mitigation efforts, sheer inability to comply with community mitigation strategies, and constrained national preparedness. This situation will reduce the benefits achieved through decades of disease control and health promotion measures, and the economic progress made during periods of global development. Without interventions, and as soon as international travel and trade resume, reservoirs of COVID-19 and other vaccine-preventable diseases in LDFCAC will continue 'feeding' developed countries with repeated infection seeds. Assuring LDFCAC equity in access to medical countermeasures, funds to mitigate the pandemic, and a paradigm change in the global development agenda, similar to the post-World War II Marshall Plan for Europe, are urgently needed. We argue for a paradigm change in strategy, including a new global pandemic financing mechanism for COVID-19 and other future pandemics. This approach should assist LDFCAC in gaining access to and membership of a global interdisciplinary pandemic taskforce to enable in-country plans to train, leverage, and maintain essential functioning and also to utilize and enhance surveillance and early detection capabilities. Such a task force will be able to build on and expand research into the management of pandemics, protect vulnerable populations through international laws/treaties, and reinforce and align the development agenda to prevent and mitigate future pandemics. Lifting LDFCAC from COVID-related failure will offer the global community the best economic dividends of the century.

After SARS-CoV-2, will H5N6 and other influenza viruses follow the pandemic path?

While the world is focused on attending, controlling, and mitigating the current pandemic of COVID-19, caused by the SARS-CoV-2, other viral threats are possibly emerging and reemerging especially in Asia, posing a risk for the spread in that region and beyond. A predictable threat is the avian influenza virus, especially H5N6, which has recently led to significant outbreaks in China and the Philippines, deserving more attention and control. In the current review, we assess the history of this highly pathogenic reemerging virus, as well as the contemporary implications of poultry outbreaks occurring in some Asian countries. We also look at outbreaks due to other strains not only in Asia but also across Europe and Africa, according to recent reports from the World Organization of Animal Health (OIE).

Air travel and COVID-19 prevention in the pandemic and peri-pandemic period: A narrative review.

Air travel during the COVID-19 pandemic is challenging for travellers, airlines, airports, health authorities, and governments. We reviewed multiple aspects of COVID peri-pandemic air travel, including data on traveller numbers, peri-flight prevention, and testing recommendations and in-flight SARS-CoV-2 transmission, photo-epidemiology of mask use, the pausing of air travel to mass gathering events, and quarantine measures and their effectiveness. Flights are reduced by 43% compared to 2019. Hygiene measures, mask use, and distancing are effective, while temperature screening has been shown to be unreliable. Although the risk of in-flight transmission is considered to be very low, estimated at one case per 27 million travellers, confirmed in-flight cases have been published. Some models exist and predict minimal risk but fail to consider human behavior and airline procedures variations. Despite aircraft high-efficiency filtering, there is some evidence that passengers within two rows of an index case are at higher risk. Air travel to mass gatherings should be avoided. Antigen testing is useful but impaired by time lag to results. Widespread application of solutions such as saliva-based, rapid testing or even detection with the help of "sniffer dogs" might be the way forward. The "traffic light system" for traveling, recently introduced by the Council of the European Union is a first step towards normalization of air travel. Quarantine of travellers may delay introduction or re-introduction of the virus, or may delay the peak of transmission, but the effect is small and there is limited evidence. New protocols detailing on-arrival, rapid testing and tracing are indicated to ensure that restricted movement is pragmatically implemented. Guidelines from airlines are non-transparent. Most airlines disinfect their flights and enforce wearing masks and social distancing to a certain degree. A layered approach of non-pharmaceutical interventions, screening and testing procedures, implementation and adherence to distancing, hygiene measures and mask use at airports, in-flight and throughout the entire journey together with pragmatic post-flight testing and tracing are all effective measures that can be implemented. Ongoing research and systematic review are indicated to provide evidence on the utility of preventive measures and to help answer the question "is it safe to fly?".