Diagnostics for COVID-19: moving from pandemic response to control.

Diagnostics have proven to be crucial to the COVID-19 pandemic response. There are three major methods for the detection of SARS-CoV-2 infection and their role has evolved during the course of the pandemic. Molecular tests such as PCR are highly sensitive and specific at detecting viral RNA, and are recommended by WHO for confirming diagnosis in individuals who are symptomatic and for activating public health measures. Antigen rapid detection tests detect viral proteins and, although they are less sensitive than molecular tests, have the advantages of being easier to do, giving a faster time to result, of being lower cost, and able to detect infection in those who are most likely to be at risk of transmitting the virus to others. Antigen rapid detection tests can be used as a public health tool for screening individuals at enhanced risk of infection, to protect people who are clinically vulnerable, to ensure safe travel and the resumption of schooling and social activities, and to enable economic recovery. With vaccine roll-out, antibody tests (which detect the host's response to infection or vaccination) can be useful surveillance tools to inform public policy, but should not be used to provide proof of immunity, as the correlates of protection remain unclear. All three types of COVID-19 test continue to have a crucial role in the transition from pandemic response to pandemic control.

Estimating the impact of virus testing strategies on the COVID-19 case fatality rate using fixed-effects models.

The SARS-CoV2 has now spread worldwide causing over four million deaths. Testing strategies are highly variable between countries and their impact on mortality is a major issue. Retrospective multicenter study with a prospective database on all inpatients throughout mainland France. Using fixed effects models, we exploit policy discontinuities at region borders in France to estimate the effect of testing on the case fatality rate. In France, testing policies are determined at a regional level, generating exogenous variation in testing rates between departments on each side of a region border. We compared all contiguous department pairs located on the opposite sides of a region border. The increase of one percentage point in the test rate is associated with a decrease of 0.0015 percentage point in the death rate, that is, for each additional 2000 tests, we could observe three fewer deaths. Our study suggests that COVID-19 population testing could have a significant impact on the mortality rate which should be considered in decision-making. As concern grows over the current second wave of COVID-19, our findings support the implementation of large-scale screening strategies in such epidemic contexts.

Mechanisms of socioeconomic differences in COVID-19 screening and hospitalizations.

BACKGROUND: Social and ecological differences in early SARS-CoV-2 pandemic screening and outcomes have been documented, but the means by which these differences have arisen are not well understood. OBJECTIVE: To characterize socioeconomic and chronic disease-related mechanisms underlying these differences. DESIGN: Observational cohort study. SETTING: Outpatient and emergency care. PATIENTS: 12900 Cleveland Clinic Health System patients referred for SARS-CoV-2 testing between March 17 and April 15, 2020. INTERVENTIONS: Nasopharyngeal PCR test for SARS-CoV-2 infection. MEASUREMENTS: Test location (emergency department, ED, vs. outpatient care), COVID-19 symptoms, test positivity and hospitalization among positive cases. RESULTS: We identified six classes of symptoms, ranging in test positivity from 3.4% to 23%. Non-Hispanic Black race/ethnicity was disproportionately represented in the group with highest positivity rates. Non-Hispanic Black patients ranged from 1.81 [95% confidence interval: 0.91-3.59] times (at age 20) to 2.37 [1.54-3.65] times (at age 80) more likely to test positive for the SARS-CoV-2 virus than non-Hispanic White patients, while test positivity was not significantly different across the neighborhood income spectrum. Testing in the emergency department (OR: 5.4 [3.9, 7.5]) and cardiovascular disease (OR: 2.5 [1.7, 3.8]) were related to increased risk of hospitalization among the 1247 patients who tested positive. LIMITATIONS: Constraints on availability of test kits forced providers to selectively test for SARS-Cov-2. CONCLUSION: Non-Hispanic Black patients and patients from low-income neighborhoods tended toward more severe and prolonged symptom profiles and increased comorbidity burden. These factors were associated with higher rates of testing in the ED. Non-Hispanic Black patients also had higher test positivity rates.

Neurosurgical Outcomes, Protocols, and Resource Management During Lockdown: Early Institutional Experience from One of the World's Largest COVID 19 Hotspots.

BACKGROUND: As the COVID-19 pandemic surpasses 1 year, it is prudent to reflect on the challenges faced and the management strategies employed to tackle this overwhelming health care crisis. We undertook this study to validate our institutional protocols, which were formulated to cater to the change in volume and pattern of neurosurgical cases during the raging pandemic. METHODS: All admitted patients scheduled to undergo major neurosurgical intervention during the lockdown period (15 March 2020 to 15 September 2020) were included in the study. The data involving surgery outcomes, disease pattern, anesthesia techniques, patient demographics, as well as COVID-19 status, were analyzed and compared with similar retrospective data of neurosurgical patients operated during the same time period in the previous year (15 March 2019 to 15 September 2019). RESULTS: Barring significant increase in surgery for stroke (P = 0.008) and hydrocephalus (P <0.001), the overall case load of neurosurgery during the study period in 2020 was 42.75% of that in 2019 (P < 0.001), attributable to a significant reduction in elective spine surgeries (P < 0.001). However, no significant difference was observed in the overall incidence of emergency and essential surgeries undertaken during the 2 time periods (P = 0.482). There was an increased incidence in the use of monitored anesthesia care techniques during emergency and essential neurosurgical procedures by the anesthesia team in 2020 (P < 0.001). COVID-19 patients had overall poor outcomes (P = 0.003), with significant increase in mortality among those subjected to general anesthesia vis-a-vis monitored anesthesia care (P = 0.014). CONCLUSIONS: Despite a significant decrease in neurosurgical workload during the COVID-19 lockdown period in 2020, the volume of emergency and essential surgeries did not change much compared with the previous year. Surgery in COVID-19 patients is best avoided, unless critical, as the outcome in these patients is not favorable. The employment of monitored anesthesia care techniques like awake craniotomy and regional anesthesia facilitate a better outcome in the ongoing COVID-19 era.

COVID-19 in Africa: an ovarian victory?

Coronavirus disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mainly attacks the respiratory system and is characterized by pneumonia, cytokine storm, coagulation disorders and severe immune downregulation. Although public health experts predicted worst outcomes in Africa, the incidence, hospitalization and mortality rates have been lower in Africa compared to other continents. Interestingly, lower incidence and mortality rates have been observed in women from Africa compared to their cohorts from other continents. Also, in the US non-Hispanic Black females have lower COVID-19 and death rates compared to their white counterparts. It's unclear why this significant difference exists; however, the ovarian function, genetics and immunological statuses could play a major role. Women of African descent have elevated levels of estrogen compared with Caucasians hence we anticipate that estrogen might offer some protection against the SARS-CoV-2 infections. The racial differences in lifestyle, age and inaccessibility to contraceptive usage might also play a role. Here, we provide insight on how the high levels of estrogen in African women might contribute to the lower cases and fatalities in Africa. Specifically, estrogen might offer protection against COVID-19 by suppressing hyper-production of cytokines, promoting anti-inflammatory cytokines, stimulating antibody production and suppressing endoplasmic reticulum (ER) stress. This will as well provide useful information on how future pandemics could be managed using Africa as a case study.