Infectious diseases

In this population based study in Denmark, the risk for reinfection with SARS-CoV-2 is generally low (higher among adults aged 65 and older). The reinfection rate was 8 per 100,000 person-days of follow-up among people aged 65 and older, versus 4-6 per 100,000 person-days among younger age groups. The authors state that these results underline that natural herd immunity will be very difficult to occur and the need for a global vaccine program in order to control the current pandemic state.

Public health medicine

This articles summarizes arguments for two approaches on vaccination strategies: keeping standard regimen or delaying the second dose. The following section is quite relevant: "Under normal circumstances, the vaccines should be deployed in keeping with the trial protocols. However, the current circumstances — a slow vaccine rollout, a limited vaccine supply, and the recent emergence of more infectious SARS-CoV-2 variants that threaten to outpace our vaccination program — are anything but normal. This may be a case in which the risks of strict adherence to the plan outweigh the risks of modifying it. Some argue that any deviation from the protocol used in the clinical trials is unscientific. But the argument is based on an overly narrow definition of science. In both trials, the cases in the placebo and active vaccine groups began to diverge about 10 days after the first dose, with growing vaccine efficacy over time. By the day of the injection of the second dose, the efficacy of the first dose was somewhere in the range of 80 to 90%."

Public health medicine

In this randomized clinical trial that included 476 patients, the duration of symptoms was not significantly different for patients who received a 5-day course of ivermectin compared with placebo (median time to resolution of symptoms, 10 vs 12 days; hazard ratio for resolution of symptoms, 1.07 - 95% CI, 0.87 to 1.32). The findings do not support the use of ivermectin for treatment of mild COVID-19.

Public health medicine

Os resultados dizem-nos que profissionais de saúde com infecção anterior por COVID-19, com base em testes sorológicos confirmados em laboratório, apresentaram respostas de títulos de anticorpos mais elevados a uma única dose de vacina de mRNA do que aqueles que não foram previamente infectados. Os autores defendem que estas pessoas, no contexto de escassez de vacinas, possam ser vacinadas com apenas 1 dose ou sejam colocadas no final da lista de prioridades.