Background The scale of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among health care workers (HCWs), particularly in resource-limited settings, remains unclear. To address this concern, universal (non-symptom-based) screening of HCWs was piloted to determine the proportion of SARS-CoV-2 infection and the associated epidemiological and clinical risk factors at a large public health care facility in Egypt. Methods Baseline voluntary screening of 4040 HCWs took place between 22 April and 14 May 2020 at 12 hospitals and medical centres in Cairo. Epidemiological and clinical data were collected using an online survey. All participants were tested for SARS-CoV-2 using reverse transcription polymerase chain reaction (RT-PCR) and rapid IgM and IgG serological tests. Results Of the 4040 HCWs screened, 170 [4.2%; 95% confidence interval (CI): 3.6-4.9] tested positive for SARS-CoV-2 by either of the three tests (i.e. infected); 125/170 (73.5%) tested PCR-positive. Most infected HCWs were nurses (97/170, 57.5%). Median age of infected HCWs was 31.5 [interquartile range (IQR): 27.0–41.3] years. Of infected HCWs, 78 (45.9%) reported contact with a suspected case and 47 (27.6%) reported face-to-face contact within 2 m with a confirmed case. The proportion of infection among symptomatic HCWs (n = 54/616) was 8.8% (95% CI: 6.7-11.3); 6/54 (11.1%) had fever ≥38°C and 7/54 (13.0%) reported severe symptoms. Most infected HCWs were asymptomatic (116/170, 68.2%). The proportion of infection among asymptomatic HCWs (n = 116/3424) was 3.4% (95% CI: 2.8-4.0). Conclusions The high rate of asymptomatic infections among HCWs reinforces the need for expanding universal regular testing. The infection rate among symptomatic HCWs in this study is comparable with the national rate detected through symptom-based testing. This suggests that infections among HCWs may reflect community rather than nosocomial transmission during the early phase of the COVID-19 epidemic in Egypt.

LP and KP were preventive factors for NEC with absolute risk reduction (AAR) 16, 15%, respectively and 18% for NS compared to placebo. Incidence of NEC and NS did not differ significantly between neonates supplemented with LP and those with KP. Preterm neonates supplemented with KP showed significantly lower incidence of NEC compared to placebo, while incidence of NS showed no significant difference between both groups. There is significant reduction in NS and NEC among neonates with positive Lactobacillus colonization of gut compared to those none colonized at day 7 (27.9 vs. 85.9%, 0 vs. 7.8%) and at day 14 (48.7 vs. 91.7% for NS and 0 vs. 20.8% for NEC). Overall comparison between the three groups showed statistical significant reduction in the incidence of NEC. Present conclusions are that early gut colonization with beneficial bacteria lowers the incidence of NEC and NS. KP retained similar benefits to live bacteria.

Based on nickel hexacyanidochromate and cobalt hexacyanidoferrate Prussian blue analogues, two series of photomagnetic/ferromagnetic sub-50 nm core multishell coordination nanoparticles have been synthesized in a surfactant-free one-pot multistep procedure with good control over the dispersity (10% standard deviation) and good agreement with the targeted size at each step. The composition and the valence state of each shell have been probed by different techniques that have revealed the predominance of Co(II)-NC-Fe(III) pairs in a series synthesized without alkali while Co(III)-NC-Fe(II) photoswitchable pairs have been successfully obtained in the photoactive coordination nanoparticles by control of Cs(+) insertion. When compared, the photoinduced behavior of the latter compound is in good agreement with that of the model one. Exchange coupling favors a uniform reversal of the magnetization of the heterostructured nanoparticles, with a large magnetization brought by a soft ferromagnetic shell and a large coercivity due to a harder photomagnetic shell. Moreover, a persistent increase of the photoinduced magnetization is observed for the first time up to the ordering temperature (60 K) of the ferromagnetic component because of a unique synergy.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection provides a critical host-immunological challenge. Aim: We explore the effect of host-genetic variation in interferon-lambda-3 rs12979860, Tolloid Like–1 (TLL1) rs17047200 and Discoidin domain receptor 1(DDR1) rs4618569 on host response to respiratory viral infections and disease severity that may probe the mechanistic approach of allelic variation in virus-induced inflammatory responses. Methods: 141 COVID-19 positive patients and 100 healthy controls were tested for interferon-lambda-3 rs12979860, TLL1 rs17047200 and DDR1 rs4618569 polymorphism by TaqMan probe-based genotyping. Different genotypes were assessed regarding the COVID-19 severity and prognosis. Results: There were statistically significant differences between the studied cases and control group with regard to the presence of comorbidities, total leucocytic count, lymphocytic count, CRP, serum LDH, ferritin and D-dimer (p < 0.01). The CC genotype of rs12979860 cytokine, the AA genotype of TLL1 rs17047200 and the AA genotype of the rs4618569 variant of DDR1 showed a higher incidence of COVID-19 compared to the others. There were significant differences between the rs4618569 variant of DDR and the outcome of the disease, with the highest mortality in AG genotype 29 (60.4%) in comparison to 16 (33.3%) and 3 (6.2%) in the AA and GG genotypes, respectively (p = 0.007*), suggesting that the A allele is associated with a poor outcome in the disease. Conclusion: Among people who carry C and A alleles of SNPs IFN-λ rs12979860 and TLL1 rs17047200, respectively, the AG genotype of the DDR1 rs4618569 variant is correlated with a COVID-19 poor outcome. In those patients, the use of anti-IFN-λ 3, TLL1 and DDR1 therapy may be promising for personalized translational clinical practice.

Background: We examined Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) seroconversion incidence and risk factors 21 days after baseline screening among healthcare workers (HCWs) in a resource-limited setting. Methods: A prospective cohort study of 4040 HCWs took place at 12 university healthcare facilities in Cairo, Egypt; April-June 2020. Follow-up exposure and clinical data were collected through online survey. SARS-CoV-2 testing was done using rapid IgM and IgG serological tests and reverse transcriptasepolymerase chain reaction (RT-PCR) for those with positive serology. Cox proportional hazards modelling was used to estimate adjusted hazard ratios (HR) of seroconversion. Results: 3870/4040 (95.8%) HCWs tested negative for IgM, IgG and PCR at baseline; 2282 (59.0%) returned for 21-day follow-up. Seroconversion incidence (positive IgM and/or IgG) was 100/2282 (4.4%, 95% CI:3.6-5.3), majority asymptomatic (64.0%); daily hazard of 0.21% (95% CI:0.17-0.25)/48 746 person-days of follow-up. Seroconversion was: 4.0% (64/1596; 95% CI:3.1-5.1) among asymptomatic; 5.3% (36/686; 95% CI:3.7-7.2) among symptomatic HCWs. Seroconversion was independently associated with older age; lower education; contact with a confirmed case >15 min; chronic kidney disease; pregnancy; change/loss of smell; and negatively associated with workplace contact. Conclusions: Most seroconversions were asymptomatic, emphasizing need for regular universal testing. Seropositivity was three-fold that observed at baseline. Cumulative infections increased nationally by a similar rate, suggesting HCW infections reflect community not nosocomial transmission.