Since the declaration of the COVID-19 pandemic, several studies have demonstrated its considerable psychological impact. The isolation and social distancing, the increased fear of being infected or infecting others and the insecurity generated by the economic impact, could contribute to an increase in the incidence of mental health issues, such as psychotic disorders.

The aim is to discuss four clinical cases in order to provide further evidence on this matter.

We report on three females and one male with no personal psychiatric history who were admitted to a tertiary hospital during the first three months after the declaration of the pandemic. The average age was 44,25 ± 14,97 years.

All patients met the International Statistical Classification of Diseases (ICD-10) criteria for acute and transient psychotic disorder. All of the episodes were triggered by the stress generated from the COVID-19. Complementary tests were unremarkable. They all tested negative for SARS-CoV-2. Rapid discharge with favorable response to relatively low doses of antipsychotics was possible with a mean length of stay of 7,25 ± 2,86 days. In two of the cases the delirious content was predominantly marked by the coronavirus itself.

It has been suggested that the intense psychosocial stress associated with a new life-threatening disease and national lockdown restrictions could be triggers for new-onset psychotic disorders. Some authors have reported cases similar to ours, which means that we could be experiencing and increase in the incidence of psychotic disorders due to the exceptional circumstances we are living around the world.

Psychotic symptoms have been linked to religious experience, but empirical evidence is scarce. We have investigated the impact of the Welsh religious revival (RR) of 1904–1905 on the number of admissions to the regional psychiatric hospital, their diagnostic features and lifelong course.

All case-notes of patients admitted to the North Wales Hospital between 1902 and 1907 were included.

There was a significant increase in admissions for brief polymorphic psychoses (BPP; ICD-10: F23.0 and F23.1) in the revival years, but the number of first admissions for other mental disorders did not change. The vast majority of BPP admissions were linked to a revival meeting and did not result in further admissions.

Intensive religious experience can lead to transient psychotic episodes. Our data also support the view that BPP triggered by life events rarely lead to chronic mental illness, distinguishing them from other psychoses and supporting the validity of the concept of reactive psychosis.