August is generally a quiet month for academics, at least in the northern hemisphere, and this leaves us with a smaller selection of papers than usual. This week we learnt that one third of deaths from COVID-19 in England were in patients with diabetes, that the prevalence of COVID-19 in healthcare workers in Long Island was lower than in the general population, suggesting that PPE is effective, and that face masks are predicted to reduce the number of infections, even if they are only partially effective.
A lipid nanoparticle containing mRNA that encodes the coronavirus spike protein was tested in 45 humans, and induced a good antibody response. Further human trials of the BNT162b1 vaccine are ongoing.
The immune response to infection was described COVID-19 patients and healthy controls in Hong Kong and Atlanta. Interferon production was impaired and levels of inflammatory mediators were enhanced, especially in severely ill patients.
Extracorporeal membrane oxygenation had a similarly positive effect on severe COVID-19 patients with acute respiratory distress syndrome as for other types of ARDS, according to a study of 83 patients in France. Another study from Chicago also found that ECMO can be effective in COVID-19 patients.
Almost 10% of healthcare workers in a New York healthcare system tested positive for a past SARS-CoV-2 infection by serology testing. Seroprevalence was lower than in the general population of Long Island, where 17% tested positive, and there was no difference between workers in high and low risk areas. This suggests that PPE is effective.
Face masks can reduce the number of infections and flatten the curve, even if they only have a limited effect, according to a modelling study. Another study found that N95 respirators past their expiry date, those that are sterilised and those that have been previously used all worked to acceptable levels, according to a study of their filtration efficiency.
Two papers from the UK looked at diabetes as a risk factor for fatal COVID-19. The first study found that of more than 23,000 COVID-19 deaths recorded in England, one third were in people with diabetes, mainly type 2. The second study found that all-cause deaths in people with type 1 and type 2 diabetes were up by 51% and 64% respectively in England during 2020, compared to previous years. Not all of these deaths were directly attributed to COVID-19, but of those that were, several risk factors were identified including non-white ethnicity, low or high BMI, and cardiovascular and renal complications of diabetes.
COVID-19 patients with haematological malignancies such as leukaemia were more likely to have a fatal outcome than the general population with COVID-19, as well as cancer patients without COVID-19, according to a study from Italy.
Biomarkers of severe disease
Lupus antigen was found in severe COVID-19 patients at a higher rate than in uninfected controls, and was associated with an increased risk of thrombosis, indicating that it may have a role in this complication.
Nursing homes in the US that were rated highly for nurse staffing had fewer COVID-19 outbreaks than those rated low. There was no correlation with high ratings for health inspection or quality measure ratings. Another study found that 28% of nursing home residents in Connecticut tested positive for SARS-CoV-2, 78% of whom were asymptomatic.
Rates of in-hospital acute myocardial infarction varied during the pandemic period, with worse patient outcomes during the early and late COVID-19 periods.
At the time of writing, New Zealand had just 1569 cases of COVID-19 and 22 deaths, with little or no ongoing transmission. Cases have just begun to increase on the islands, showing the challenges of remaining free from imported cases.