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Serogroup epidemiology of invasive meningococcal disease (IMD) is constantly evolving, varying by time and location. Surveillance reports have indicated a rise in meningococcal serogroup Y (MenY) in some regions in recent years. This systematic literature review explores the evolving epidemiology of MenY IMD globally based on review of recent articles and national surveillance reports published between 1 January 2010 and 25 March 2021. Generally, MenY incidence was low (<0.2/100,000) across all ages in most countries. The reported incidence was more frequent among infants, adolescents, and those aged ≥65 years. More than 10% of all IMD cases were MenY in some locations and time periods. Implementation of vaccination evolved over time as the rise in MenY IMD percentage occurred. Cases decreased in countries with quadrivalent vaccine programs (e.g., United Kingdom, the Netherlands, United States, and Australia), whereas the MenY burden increased and made up a large proportion of cases in areas without vaccine programs. Continuous monitoring of epidemiologic changes of IMD is essential to establish MenY burden and for implementation of prevention strategies.
Identifying persons with HIV (PWH) at increased risk for Alzheimer’s disease (AD) is complicated because memory deficits are common in HIV-associated neurocognitive disorders (HAND) and a defining feature of amnestic mild cognitive impairment (aMCI; a precursor to AD). Recognition memory deficits may be useful in differentiating these etiologies. Therefore, neuroimaging correlates of different memory deficits (i.e., recall, recognition) and their longitudinal trajectories in PWH were examined.
Design:
We examined 92 PWH from the CHARTER Program, ages 45–68, without severe comorbid conditions, who received baseline structural MRI and baseline and longitudinal neuropsychological testing. Linear and logistic regression examined neuroanatomical correlates (i.e., cortical thickness and volumes of regions associated with HAND and/or AD) of memory performance at baseline and multilevel modeling examined neuroanatomical correlates of memory decline (average follow-up = 6.5 years).
Results:
At baseline, thinner pars opercularis cortex was associated with impaired recognition (p = 0.012; p = 0.060 after correcting for multiple comparisons). Worse delayed recall was associated with thinner pars opercularis (p = 0.001) and thinner rostral middle frontal cortex (p = 0.006) cross sectionally even after correcting for multiple comparisons. Delayed recall and recognition were not associated with medial temporal lobe (MTL), basal ganglia, or other prefrontal structures. Recognition impairment was variable over time, and there was little decline in delayed recall. Baseline MTL and prefrontal structures were not associated with delayed recall.
Conclusions:
Episodic memory was associated with prefrontal structures, and MTL and prefrontal structures did not predict memory decline. There was relative stability in memory over time. Findings suggest that episodic memory is more related to frontal structures, rather than encroaching AD pathology, in middle-aged PWH. Additional research should clarify if recognition is useful clinically to differentiate aMCI and HAND.
This Element examines two prominent public health crises – the emergence of bovine spongiform encephalopathy (BSE) in British cattle and the COVID-19 pandemic. It contends that a group of arguments called the informal fallacies functioned as cognitive heuristics and facilitated public health reasoning during both crises. These arguments, which include the argument from ignorance, the argument from authority, and circular argument, are particularly well adapted to the type of uncertainty that surrounds the emergence of novel infectious diseases. By bridging gaps in knowledge, these arguments can facilitate reasoning when evidence about these diseases is limited and the need to take action is urgent. The Element charts a public health journey beginning in the 1950s with a disease called kuru, then examines the response to the emergence of BSE in 1986 and extends to the present day with the COVID-19 pandemic. This title is also available as Open Access on Cambridge Core.
Studies on climate variables and food pathogens are either pathogen- or region-specific, necessitating a consolidated view on the subject. This study aims to systematically review all studies on the association of ambient temperature and precipitation on the incidence of gastroenteritis and bacteraemia from Salmonella, Shigella, Campylobacter, Vibrio, and Listeria species. PubMed, Ovid MEDLINE, Scopus, and Web of Science databases were searched up to 9 March 2023. We screened 3,204 articles for eligibility and included 83 studies in the review and three in the meta-analysis. Except for one study on Campylobacter, all showed a positive association between temperature and Salmonella, Shigella, Vibrio sp., and Campylobacter gastroenteritis. Similarly, most of the included studies showed that precipitation was positively associated with these conditions. These positive associations were found regardless of the effect measure chosen. The pooled incidence rate ratio (IRR) for the three studies that included bacteraemia from Campylobacter and Salmonella sp. was 1.05 (95 per cent confidence interval (95% CI): 1.03, 1.06) for extreme temperature and 1.09 (95% CI: 0.99, 1.19) for extreme precipitation. If current climate trends continue, our findings suggest these pathogens would increase patient morbidity, the need for hospitalization, and prolonged antibiotic courses.
Between 2016 and 2020 the Australian government established a regional health security diplomacy project, known as the Indo–Pacific Centre for Health Security. In light of the COVID-19 pandemic, the initiative looked prescient. Its roots, however, could be traced back to Australia’s engagement with health security in the early 2000s. Then, as now, the government aligned its foreign policy agenda with health – specifically emerging infectious diseases – as a ‘scaled up’ approach comprising diplomatic, aid, and research and development. To explain Australia’s evolving relationship with health security this chapter proceeds in four parts. First, health security is situated with the recent tradition of ‘non-traditional security’. The second part examines the establishment of health security as a core theme in Australia’s response to global challenges. The third part turns to the government’s strategy and especially the Indo–Pacific Centre for Health Security both before and during the COVID-19 era. Finally, the chapter examines how Australia conceptualised its leadership role in regional health security.
Contemporary understanding of the mechanisms of disease increasingly points to examples of “genetic diseases” with an infectious component and of “infectious diseases” with a genetic component. Such blurred boundaries generate ethical, legal, and social issues and highlight historical contexts that must be examined when incorporating host genomic information into the prevention, outbreak control, and treatment of infectious diseases.
Occurrence of cryptosporidiosis has been associated with weather conditions in many settings internationally. We explored statistical clusters of human cryptosporidiosis and their relationship with severe weather events in New Zealand (NZ). Notified cases of cryptosporidiosis from 1997 to 2015 were obtained from the national surveillance system. Retrospective space–time permutation was used to identify statistical clusters. Cluster data were compared to severe weather events in a national database. SaTScan analysis detected 38 statistically significant cryptosporidiosis clusters. Around a third (34.2%, 13/38) of these clusters showed temporal and spatial alignment with severe weather events. Of these, nearly half (46.2%, 6/13) occurred in the spring. Only five (38%, 5/13) of these clusters corresponded to a previously reported cryptosporidiosis outbreak. This study provides additional evidence that severe weather events may contribute to the development of some cryptosporidiosis clusters. Further research on this association is needed as rainfall intensity is projected to rise in NZ due to climate change. The findings also provide further arguments for upgrading the quality of drinking water sources to minimize contamination with pathogens from runoff from livestock agriculture.
COVID-19 has significantly impacted society for over 2.5 years, and Long COVID is concerning for its long-term impact on the healthcare system. Further, cognitive and emotional functioning in Long COVID has limited research, but 2 recent studies (Whiteside et al., 2022a, Whiteside et al., 2022b) examined cognitive and emotional functioning in Long COVID patients approximately 6 months post-diagnosis. The studies found limited cognitive deficits, but significant depression and anxiety, which in turn were the best predictors of low average cognitive scores. Further, the mean Personality Assessment Inventory (PAI) profile included highest mean elevations on somatic preoccupation (SOM) and depression (DEP) subscales. To further explore personality functioning in Long COVID, this study compared PAI profiles of Long COVID patients with a potentially similar group with post-concussion syndrome (PCS) which has been shown to have a strong psychological component.
Participants and Methods:
Participants included 44 consecutive outpatients (Mean age = 47.89, SD = 13.05, 84% Female, 75% Caucasian) referred from a Long COVID clinic with cognitive complaints related to COVID, while the comparison group of PCS patients included 50 consecutive referrals (Mean age = 38.82, SD = 16.24, 52% Female, 90% Caucasian) related to cognitive complaints attributed to PCS. A series of t-tests between the 2 groups was conducted on the PAI validity, clinical, interpersonal, and treatment consideration scales. PAI clinical subscales were also compared. To control for multiple comparisons, p < .01 was utilized and effect sizes were compared.
Results:
The results demonstrated that both Long COVID (SOM M = 68.66, SD = 12.56; DEP M = 63.39, SD = 12.70) and PCS groups (SOM M = 65.28, SD = 12.06; DEP M = 70.32, SD = 16.15) displayed the highest mean elevations on PAI SOM and DEP scales but no statistically significant differences in mean scale elevations between Long COVID and PCS groups on SOM (t [92] = 1.33, p = .80) and DEP (t [92] = -2.11, p = .097). However, results demonstrated statistically significant differences on the paranoia subscale (PAR; t [92] = -3.27, p = .009), antisocial features subscale (ANT; t [92] = -2.22, p = .01), stress subscale (STR; t [90] = -3.51, p = .006) and suicidal ideation subscale (SUI; t [92] = -2.73, p = .000) of the PAI. Specifically, the mean scores for the PCS group were higher across the paranoia (M = 57.30), antisocial features (M= 52.24), stress (M = 58.44), and suicidal ideation subscales (M = 57.82) of the PAI than the Long COVID group. While these patterns of reporting differed between groups, mean scores for both groups were in the normal range.
Conclusions:
Results support the similarities in emotional/personality functioning across Long COVID and PCS patients and the importance of evaluating psychological functioning in these samples as a standard part of neuropsychological evaluations. Further, the results suggest that psychological treatment strategies utilized with PCS patients may be helpful for Long COVID patients, but more research is needed.
To evaluate changes in neuropsychiatric symptoms among patients with multiple sclerosis (MS) following coronavirus disease of 2019 (COVID-19) infection using the National COVID Cohort Collaborative (N3C). The N3C represents the largest cohort of COVID-19 cases, through the unification of electronic health records from over 60 medical centers.
Participants and Methods:
Out of 5,631,225 COVID-19 confirmed positive patients, we identified a cohort of patients with MS who were diagnosed with COVID-19. Conditions were searched using terms denoting common neuropsychiatric comorbid diagnoses, including anxiety, depression, pain, sleep disorders, fatigue, and cognitive disorders. We examined descriptively the percentages of patients who were newly diagnosed with each comorbid condition after COVID-19 infection. Additionally, we searched for various patient-reported outcome measures in the N3C dataset; only the Patient Health Questionnaire-9 (PHQ-9) had an adequate sample size in our cohort for analysis. To control for variability due to non-COVID-19 factors, we only included PHQ-9 scores that were reported one year before and after COVID-19 infection. A repeated-measures analysis of variance (ANOVA) was conducted to analyze the difference between PHQ-9 scores before and after COVID-19 diagnosis among MS patients.
Results:
In our final dataset, there were 40,690 patients who were diagnosed with MS and COVID-19. Among patients without pre-existing anxiety conditions, 9.18% were diagnosed with an anxiety disorder after COVID-19 infection. Among those who did not have a pre-existing cognitive disorder, 1.73% had such diagnoses after COVID-19 infection. Among those without previous depressive disorders, 8.89% were diagnosed with a depressive disorder after COVID-19 infection. Of those without fatigue conditions prior to COVID-19 in their medical records, 8.81% had documented fatigue in their records after contracting COVID-19. Of those without pain conditions in their medical records, 11.37% had documented pain in their records after COVID-19 infection. Finally, among patients without pre-existing sleep disorders, 8.71% were diagnosed with sleep disorders after COVID-19 infection. Regarding PHQ-9 scores, 50 patients had documented scores before their COVID-19 diagnosis and 50 after COVID-19 diagnosis (17 had scores for both before and after COVID-19 diagnosis). There was no significant difference in PHQ-9 scores before and after COVID-19 diagnosis (F(df) = 0.326, p = 0.572; meanbefore = 8.77, meanafter = 9.32).
Conclusions:
Approximately 2-11% of MS patients developed new neuropsychiatric conditions after COVID-19 infection, with pain being the most common, followed by anxiety, fatigue, depression, and sleep disorders. Cognitive disorders were the least prevalent new onset neuropsychiatric sequelae of COVID-19 in this cohort. Additionally, there was a non-significant increase in severity of depressive symptoms, as indicated by a 1.36-point increase in PHQ-9 scores. These results suggest that patients with MS who have also been diagnosed with COVID-19 may be at risk for developing newly onset neuropsychiatric symptoms.
Cognitive difficulties are amongst the most frequently reported sequelae following COVID-19 infection, even in those experiencing mild to moderate illness (Matos et al., 2021). Recent research has identified patterns of diminished cognitive performance on tests of memory and executive functioning in COVID-19 cases; however, the etiology of neurocognitive difficulties remains unclear (Delgado-Alonso et al., 2022). Emerging evidence has identified moderate associations between decreased performance on neuropsychological tests of memory and elevated anxiety and depression symptom reporting in COVID-19 patients. Similar associations are well-established in the literature in persons with anxiety and depression disorders, warranting further investigation as to whether mental health variables such as internalizing symptom severity may moderate the association between COVID-19 illness and cognitive difficulties. This study examined how internalizing symptoms as indexed by depression and anxiety symptom scales may differentially influence performance on neuropsychological tests of memory between persons who have and have not had COVID-19.
Participants and Methods:
In this cross-sectional study, 104 adults aged 19-80, were recruited in Ontario and British Columbia, Canada; 84 adults met inclusion criteria and participated in neuropsychological testing. There were 40 participants who tested positive for COVID-19 infection (N=44 with no suspected exposures or confirmed diagnosis of COVID-19). Participants had no history of dementia, mild cognitive impairment, or other known neurological disorder. Anxiety and depression symptoms were measured using the Generalized Anxiety Disorder-7 (GAD-7) and Center for Epidemiologic Studies Depression Scale (CES-D) via self-report on Qualtrics. Memory encoding and delayed recognition performance were assessed using the Hopkins Verbal Learning Test Revised (HVLT-R) and the Neuropsychological Assessment Battery Shape Learning subtest (NAB-SL). To test for potential moderating effects of anxiety and depression symptoms on the association between COVID-19 infection status and memory performance, a series of multiple linear regressions were conducted. Age and sex were included as covariates in all analyses.
Results:
Moderation analyses revealed that the interaction between COVID-19 infection and anxiety symptoms accounted for a significant portion of variance in both HVLT-R recognition (B= -0.78, SE= 0.34, p<0.05) and NAB-SL delayed recognition scores (B= -0.83, SE= 0.35, p<0.05). Simple slopes analyses revealed that among participants who tested positive for COVID-19 infection, higher GAD-7 scores were associated with lower verbal and visual recognition scores. A similar interaction was observed between COVID-19 and depressive symptoms in accounting for variance in NAB-SL delayed recognition scores, however, for that model the threshold of p=0.05 was not met in our small sample (p=0.07).
Conclusions:
Findings demonstrate that anxiety symptom severity had a moderating effect on the impact of COVID-19 on delayed retrieval of verbal and visual information from memory. Future work in a larger sample is needed to further elucidate the potential moderating role of depression on memory in COVID-19 positive persons, as the current work suggests that depression symptoms could have a similar impact as anxiety. Further identifying the relationships between key modifiable psychological factors such as anxiety and memory following COVID-19 infection will provide insight into potential interventions to minimize the negative effects of internalizing symptoms on long-term cognitive outcomes.
Children with post-acute sequelae of COVID-19 (PASC) often report fatigue, attention problems, anxiety, and low mood. Sluggish cognitive tempo (SCT) is a constellation of behavioral symptoms (e.g., drowsiness, moving slowly, mental fogginess, daydreaming, confusion, or inattention) often associated with but distinct from attention-deficit/hyperactivity disorder (ADHD), executive function deficits and depressive symptoms. Given the apparent overlapping symptoms of PASC and SCT, this retrospective chart review aimed to 1) characterize SCT symptoms among pediatric patients with PASC relative to published normative and clinically referred samples, and 2) examine associations between subscales of SCT with ADHD symptoms, depression, anxiety, and functional impairment in this clinical sample.
Participants and Methods:
This study included retrospective data from 25 patients with PASC (17 females; Mean age=13.73 years, SD=2.07, range=8-19) who were referred for a neuropsychological evaluation following a multidisciplinary visit at a post-COVID-19 rehabilitation clinic within an academic medical center. Patients’ caregivers completed the SCT Scale, ADHD Rating Scale 5 (ADHD-RS-V),
Conners Comprehensive Behavior Rating Scale (CBRS), and Impairment Rating Scale (IRS). Higher scores on the SCT, CBRS, and IRS total reflect more problems in the specified area. Welch’s t-tests were utilized to compare SCT scores from our cohort of pediatric patients with PASC relative to a normative community sample (Penny et al., 2009) and a heterogeneous clinically-referred sample (Koriakin et al., 2015). Bivariate correlations were computed to examine associations between SCT (Daydreamy, Low Initiation, Sluggish/Sleepy), ADHD (Inattention and Hyperactivity subscales from the ADHD-RS-V), affective symptoms (Major Depressive Episode (MDE) and Generalized Anxiety Disorder (GAD) scales from the CBRS), and functional impairment (average score from IRS). Multiple linear regressions were used to determine whether SCT factors independently contribute to variance in functional deficits after accounting for age of evaluation, low mood, and anxiety.
Results:
Sluggish/Sleepy and Low Initiation were elevated in our cohort with PASC as compared to normative and mixed clinical samples from Penny et al. and Koriakin et al. (t>4.36, p<0.001). Patients with PASC had lower scores on the Daydreamy SCT scale than the clinically referred cohort (t=2.06, p=0.049), but similar to the normative sample (t=1.48, p=0.15). After controlling for age of testing, of the SCT subscales, only Low Initiation was associated with MDE (r=0.62, p=0.005), GAD (r=0.56, p=0.01) and overall Functional Impairment (r=0.48, p=0.04). Low Initiation was not correlated with Inattention or Hyperactivity. Notably, multiple regressions revealed Low Initiation scores were not associated with functional impairment when accounting for depression and anxiety symptoms(Low Initiation: ß=0.48, p=0.04; Low Initiation when depression and anxiety are included in independent regression models: ßs=0.13 and 0.29, ps=0.58 and 0.27 respectively).
Conclusions:
Children and adolescents with PASC demonstrate more sluggish/sleepy presentation and difficulties with initiating activities or directing effort, as compared to normative and mixed clinically referred samples. Low initiation was associated with symptoms of MDE and GAD and functional impairment, but not with symptoms of ADHD. Depression and anxiety may moderate the association between poor initiation with functional impairment, highlighting the importance of psychological interventions to address mental health among youth with PASC and behavioral/cognitive concerns.
Central nervous system (CNS) infections with the dematiaceous fungus Cladophialophora bantiana (C. bantiana) are extremely rare, with approximately 120 confirmed cases reported as of 2016. C. bantiana is a highly neurotropic and thermotolerant fungus found in soil worldwide. The mode of entry into the CNS remains unknown, but inhalation of fungal spores or subcutaneous trauma have been suggested. Entry of fungal spores can cause cerebral phaeohyphomycosis with the main clinical manifestation of a brain abscess. Symptoms are non-specific and can include headache, fever, hemiparesis, aphasia, visual disturbances, and confusion. C. bantiana cerebral phaeohyphomycosis occurs in both immunocompetent and immunocompromised individuals, with a slightly higher prevalence in immunocompetent males for unknown reasons. Diagnosis is often delayed due to its nonspecific presentation and prevalence in individuals without pre-existing immunological disease. Prognosis is poor, with mortality rates of approximately 70% despite aggressive treatment. Treatment is not standardized but may include several anti-fungal agents and surgical intervention. Case reports documenting the variability seen with cerebral phaeohyphomycosis by C. bantiana can provide valuable insight into this emerging disease. C. bantiana’s neurotropic propensity also warrants cognitive investigation of the disease; however, there are currently limited descriptions of cognitive findings in published case reports of C. bantiana CNS infections.
Participants and Methods:
Here, we describe a case of a 35-year-old immunocompetent, college educated male with a CNS C. bantiana infection, presumably following a fall while biking in Costa Rica. First symptoms included left sided facial palsy, headache, and hand weakness, prompting extensive diagnostic workup, with diagnosis of C. bantiana infection confirmed 8 months after symptom onset. Initial treatment included anti-fungal agents and steroids, but his course of infection was complicated by infectious vasculitis with posterior circulation infarcts and obstructive hydrocephalus requiring ventriculoperitoneal shunt placement two years following the fungal infection diagnosis. The most recent brain MRI revealed encephalomalacia in global periventricular areas, two small masses, likely representing small fungal phlegmons, and enhancing lesions in the upper cervical spinal canal.
Results:
The patient reported cognitive changes following the infarcts and shunt placement including difficulties with spatial navigation, following directions, and articulating thoughts. Memory concerns and lapses in judgment were also reported. Results from a neuropsychological evaluation revealed high average baseline intellectual abilities with decrements in visuospatial processing, processing speed, executive functioning, and aspects of memory stemming from his executive dysfunction. At the time, his cognitive profile suggested parietal and frontosubcortical systems disruption meeting criteria for mild cognitive impairment. Two years later, the patient reported continuing cognitive difficulties prompting a follow-up neuropsychological evaluation. Results were similar to his first evaluation, revealing deficits in aspects of visuospatial processing, decreased verbal and visual learning, bradyphrenia and processing speed deficits, and difficulties with visual planning and organization. Minimal anxiety and depression, but increased apathy and executive dysfunction were endorsed on self-report measures.
Conclusions:
This case report highlights neurological sequela resulting from CNS infection with C. bantiana, -with a course complicated by subsequent strokes, hydrocephalus, and cognitive impairment-, and contributes additional insight into the relatively limited existing reports of an extremely rare but emerging disease.
Many individuals with COVID-19 develop mild to moderate physical symptoms that can last days to months. In addition to physical symptoms, individuals with COVID-19 have reported depressive symptoms and cognitive decline, posing a long-term threat to mental health and functional outcomes. Few studies have examined the presence of co-occurring depression and subjective cognitive decline in individuals who tested positive for COVID-19. The current study examined whether having COVID-19 is subsequently associated with greater depressive symptoms and subjective cognitive decline when compared to healthy individuals. Our study also examined differential associations between symptoms of depression and subjective cognitive decline between individuals who have and have never had COVID-19.
Participants and Methods:
Adults (N = 104; mean age = 37 years, 69% female) were recruited online from Ontario and British Columbia, Canada. Participants were categorized into two groups: (1) persons who tested positive for COVID-19 at least three months prior, had been symptomatic, and had not been ventilated (N = 50); and (2) persons who have never been suspected of having COVID-19 (N = 54). The Center for Epidemiological Studies Depression Scale (CES-D) and the Subjective Cognitive Decline Questionnaire (SCD-Q) were administered to both groups as part of a larger clinical neuropsychological evaluation. Two separate linear regression analyses were conducted to examine the association of COVID-19 with depressive symptoms and subjective cognitive decline. A moderation analysis was performed to examine whether depressive symptoms were associated with subjective cognitive decline and the extent to which this differed by group (COVID-19 and controls). Participants’ age, self-reported sex, and history of depression were included as covariates.
Results:
The first regression model explained 17.2% of the variance in CES-D scores. It was found that the COVID-19 group had significantly higher CES-D scores (ß = .20, p = .03). The second regression model explained 35.9% of the variance in SCD-Q scores. Similar to the previous model, it was found that the COVID-19 group had significantly higher SCD-Q scores compared to healthy controls (ß = .22 p = .01). Lastly, the moderation model indicated that higher CES-D scores were associated with higher SCD-Q scores (ß = .43, p < .01), but there was no statistically significant group X CES-D score interaction.
Conclusions:
These findings suggest that individuals who previously experienced a mild to moderate symptomatic COVID-19 infection report greater depressive symptom severity as well as greater subjective cognitive decline. Additionally, while more severe depressive symptoms predicted greater subjective cognitive decline in our sample, the magnitude of this association did not vary between those with and without a previous COVID-19 infection. While the underlying neurobiological and social mechanisms of cognitive difficulties and depressive symptoms in persons who have had COVID-19 have yet to be fully elucidated, our findings highlight treatment for depression and cognitive rehabilitation as potentially useful intervention targets for the post COVID-19 condition.
Published results focusing on language assessment in acutely recovered COVID-19 patients have shown communication problems in this group, including significant cognitive-linguistic disruptions in verbal fluency (Cummings, 2022). Extant research also indicates that poorer health-related outcomes, such as reduced physical functioning and quality of life, co-occur with cognitive difficulties post-COVID-19 infection (Mendez et al., 2021; Tabacof et al., 2022). Understanding what factors may worsen the impact of COVID-19 on cognition, and aspects of language function specifically, is necessary to determine who is at greatest risk of adverse outcomes following infection. Our goal was to examine the effect of health-related outcomes on language abilities, specifically verbal fluency, post-COVID-19 infection.
Participants and Methods:
37 adults 19 years and older (M age = 38.78, 67.5% female, 92.5%> high school education) were recruited from British Columbia and Ontario, Canada. Participants provided documentation indicating they had had a COVID-19 infection at least 3 months prior to participation. Participants completed a series of online questionnaires, including the Short Form Health Survey (SF-20), to measure aspects of health-related quality of life. The SF-20 measures dimensions of functioning (physical, social, role) and well-being (mental health, health perception, pain). For each parameter except pain, higher scores indicate better functioning/well-being; for pain higher scores indicate greater pain levels. Participants also completed neuropsychological tests, including measures of verbal fluency, via teleconference. Animals and F-A-S total scores were combined to represent verbal fluency (semantic and phonemic, respectively) performance. To assess the impact of health outcomes on verbal fluency performance, hierarchical regression analyses were conducted. The six SF-20 subscale scores were entered as predictors and verbal fluency score (sum) as the outcome. Age and sex (Male/Female) were controlled for in the model.
Results:
Age and sex were not significantly related to verbal fluency scores in our sample. After controlling for these demographics, the overall model including SF-20 subscales did not significantly predict fluency performance (F (8, 28) = 1.04, p = .433). However, Pain scores did individually predict verbal fluency performance (B = 5.60, t = 2.53, p = <.05). Unexpectedly, pain ratings were positively associated with fluency scores, such that each increase in pain rating (e.g., “none” to “mild”) was associated with a fluency score increase of 5.60 points (i.e., 5.6 more words stated across administered tasks).
Conclusions:
These preliminary findings suggest that participants’ self-reported pain severity was positively associated with verbal fluency task performance in our sample (i.e., greater pain severity predicting better fluency). These findings are contrary to substantial evidence showing the deleterious effects of pain on cognitive functions in other populations (Khera & Rangasamy, 2021). It is possible that findings may be explained by a potential unknown intervening variable not included in our model. This is the first study to our knowledge to examine associations between experienced pain and verbal fluency performance post-COVID-19 infection. It will be important for future work to not only utilize more robust measures of pain experiences and explore more areas of cognition and language, but also to employ larger samples and examine a broader set of covariates.
Emerging evidence suggests that individuals recovering from COVID-19 perceive changes to their cognitive function and psychological health that persist for weeks to months following acute infection. Although there is a strong relationship between initial COVID-19 infection severity and development of prolonged symptoms, there is only a modest relationship between initial COVID-19 severity and self-reported severity of prolonged symptoms. While much of the research has focused on more severe COVID-19 cases, over 90% of COVID-19 infections are classified as mild or moderate. Previous work has found evidence that non-severe COVID-19 infection is associated with cognitive deficits with small-to-medium effect sizes, though patients who were not hospitalized generally performed better on cognitive measures than did those who were hospitalized for COVID-19 infection. As such, it is important to also quantify subjective cognitive functioning in non-severe (mild or moderate) COVID-19 cases. Our meta-analysis examines self-reported cognition in samples that also measured objective neuropsychological performance in individuals with non-severe COVID-19 infections in the post-acute (>28 days) period.
Participants and Methods:
This study’s design was preregistered with PROSPERO (CRD42021293124) and used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist for reporting guidelines. Inclusion criteria were established prior to article searching and required peer-reviewed studies to have (1) used adult participants with a probable or documented diagnosis of non-severe (asymptomatic, mild, or moderate) COVID-19 who were in the post-acute stage (>28 days after initial infection); (2) used objective neuropsychological testing to document cognitive functioning; and (3) include a self-report measure of subjective cognition. At least two independent reviewers conducted all aspects of the screening, reviews, and extraction process. Twelve studies with three types of study design met full criteria and were included (total n=2,744).
Results:
Healthy comparison group comparison: Compared with healthy comparison participants, the post-COVID-19 group reported moderately worse subjective cognition (d=0.546 [95% CI (0.054, 1.038)], p=0.030). Severity comparison: When comparing hospitalized and not hospitalized groups, patients who were hospitalized reported modestly worse subjective cognition (d=-0.241, [95% CI (-0.703, 0.221)], p=0.30), though the difference was not statistically significant. Normative data comparison: When all non-severe groups (mild and moderate; k=12) were compared to the normative comparison groups, there was a large, statistically significant effect (d=-1.06, [95% CI (-1.58, -0.53)], p=0.001) for self-report of worse subjective cognitive functioning.
Conclusions:
There was evidence of subjective report of worse cognitive functioning following non-severe COVID-19 infection. Future work should explore relationships between objective neuropsychological functioning and subjective cognitive difficulties following COVID-19.
“Brain fog” is one of the most common consequences of developing COVID-19. The available research focuses mainly on the decline in overall cognitive performance. Much less papers refers to the evaluation of particular cognitive domains, and when it does, it focuses particularly on attention and memory disorders. The available data on the effects of COVID-19 infection on visuospatial functions is sparse, so the aim of this study was to investigate the level of visuospatial functioning in adults who have a history of COVID-19 infection. It was also intended to explore whether there is a protective effect of vaccination on the cognitive functioning after COVID-19.
Participants and Methods:
The group included sixty volunteers (age: M = 40.12, SD = 16.78; education: M = 12.95 SD = 2.25; sex: M = 20, F = 40) - thirty seven with a history of COVID-19 and twenty three who were never infected with SARS-COV-2. Of those with a history of COVID-19, twenty-four were vaccinated at the time of the disease, and thirteen were not. Subjects from individual groups did not differ demographically. Participants were examined with a set of neuropsychological tests to assess: a) general cognitive functioning - Montreal Cognitive Assessment (MoCA), b) attention - d2 Test of Attention, memory - Rey-Osterieth Complex Figure - delayed recall, and c) visuospatial functions - Rey-Osterieth Complex Figure - copy, Block Design - subtest of WAIS-R and three experimental tasks consisting of: incomplete pictures, rotating puzzles, counting cubes in a 3D tower.
Results:
Subjects who had a history of COVID-19 achieved significantly lower scores in the MoCA test (p = 0.033) compared to those who did not suffer from COVID-19. They also needed more time in mental rotation task (p = 0,04). Statistically significant differences were also found in the d2 Test of Attention GP score (p = 0.001). Moreover, in group of adults who had a history of COVID-19, statistically significant differences were found between the vaccinated and unvaccinated subjects. It turned out that those who were vaccinated during their illness performed significantly better than those who were unvaccinated in the following cognitive domains: attention (d2 Test of Attention) and visuospatial functions (Rey-Osterieth Complex Figure test - copy, Block Design from WAIS-R, as well as experimental trials: incomplete pictures, rotating puzzles, counting cubes).
Conclusions:
Among adults who have been infected with COVID-19, there is a decrease in general cognitive performance, but also in individual cognitive abilities, including visuospatial functions. Vaccination significantly reduces the risk of cognitive impairment.
To effectively diagnose and treat cognitive post-COVID-19 symptoms, it is important to understand objective cognitive difficulties across the range of acute COVID-19 severity. The aim of this meta-analysis is to describe objective neuropsychological test performance in individuals with non-severe (mild/moderate) COVID-19 cases in the post-acute stage of infection (>28 days after initial infection).
Participants and Methods:
This meta-analysis was pre-registered with Prospero (CRD42021293124) and utilized the PRISMA reporting guidelines, with screening conducted by at least two independent reviewers for all aspects of the screening and data extraction process. Inclusion criteria were established before the article search and were as follows: (1) Studies using adult participants with a probable or formal and documented diagnosis of COVID-19 in the post-acute stage of infection; (2) Studies comparing cognitive functioning using objective neuropsychological tests in one or more COVID-19 groups and a comparison group, or one group designs using tests with normative data; (3) Asymptomatic, mild, or moderate cases of COVID-19. Twenty-seven articles (n=18,202) with three types of study designs and three articles with additional longitudinal data met our full criteria.
Results:
Individuals with non-severe initial COVID-19 infection demonstrated worse cognitive performance compared to healthy comparison participants (d=-0.412 [95% CI, -0.718, -0.176)], p=0.001). We used metaregression to examine the relationship between both average age of the sample and time since initial COVID-19 infection (as covariates in two independent models) and effect size in studies with comparison groups. There was no significant effect for age (b=-0.027 [95% CI (0.091, 0.038)], p=0.42). There was a significant effect for time since diagnosis, with a small improvement in cognitive performance for every day following initial acute COVID-19 infection (b=0.011 [95% CI (0.0039, 0.0174)], p=0.002). However, those with mild (non-hospitalized) initial COVID-19 infections performed better than did those who were hospitalized for initial COVID-19 infections (d=0.253 [95% CI (0.372, 0.134)], p<0.001). For studies that used normative data comparisons, there was a small, non-significant effect compared to normative data (d=-0.165 [95% CI (-0.333, 0.003)], p=0.055).
Conclusions:
Individuals who have recovered from non-severe cases of COVID-19 may be at risk for cognitive decline or impairment and may benefit from cognitive health interventions.
hough there is much that is unknown about “post-COVID conditions” the Center for Disease Control (CDC) recognizes that these conditions represent a wide array of new, returning, or ongoing health issues in individuals who have been infected with the novel corona virus, COVID-19. This case series describes the emotional and cognitive screening of three females in their 50's who contracted COVID-19, and were hospitalized during the course of their illness. This case series hopes to provide an initial framework to discuss the recovery trajectory of post-COVID patients who were hospitalized, who have experienced residual post-traumatic stress and cognitive symptoms.
Participants and Methods:
Three middle-aged female patients (ages 52, 53, 55) were screened in an outpatient post-COVID recovery center for initial and post-COVID emotional, cognitive, and physical symptoms. All three women reported being hospitalized during their illness. The Post-Traumatic Stress Disorder - Primary Care PTSD Screen for DSM-5 (PC-PTSD-5) was administered via clinical interview and the patients were asked about subjective cognitive complaints related to concentration, memory, and word finding.
Results:
All three women reported persisting cognitive problems, including difficulties with concentration, problems with memory, and word finding difficulties. They also endorsed symptoms of post-traumatic stress, such as avoidance of thoughts and events, as well as recurrent nightmares related to the course of their illness.
Conclusions:
The CDC notes that there are no tests that specifically evaluate the multitude of post-COVID conditions. Regardless, this case series suggests that emotional and cognitive screeners may assist in treatment planning and support recovery in this population. Future research should examine the exact nature of the relationship between hospitalization, emotional symptoms, and cognitive functioning in post-COVID patients.
Acute cognitive complications following COVID-19 infection have been appreciated in a subset of patients since the early months of the global pandemic. Emerging data reveal that some patients go on to experience cognitive improvement, whereas others may experience further cognitive decline. We aimed to assess trajectories and predictors of cognitive change in a sample of post-COVID-19 patients.
Participants and Methods:
This prospective cohort study assessed longitudinal cognitive change in adults receiving care for COVID-19 in the Johns Hopkins Post-Acute COVID-19 Team (JH PACT) clinic. Participants self-administered the Digital Automated Neurobehavioral Assessment (DANA) battery of seven cognitive tests and a performance-based measure of cognitive fatigue on up to six occasions over six weeks. Improvement or decline between the first and last assessment was defined as change of >1 standard deviation of the baseline mean of each outcome. Potential predictors of change included demographic features (age, sex, race/ethnicity, education), COVID-19 illness characteristics (hospitalization or ICU stay, months since symptom onset), and comorbid disease burden. Analyses included measures of central tendency, independent samples t-tests, and chi-square tests of independence.
Results:
Of the 36 enrolled participants, 29 (81%) completed at least one DANA assessment (M = 4.7 assessments, SD = 1.8). Those completing at least three assessments (n = 24, 66.7%) were included in the present analyses (71% female; 58% white; M age = 54 years, SD = 10.9; M education = 14.6 years, SD = 2.4; M months since COVID-19 symptom onset at recruitment = 9.8, SD = 4.7; M comorbidities = 2.8, SD = 2.0). Fatigue was the most frequently improved outcome measure, with 41.7% of participants scoring >1 standard deviation above the baseline mean fatigue score at their final assessment. Among cognitive outcomes, the greatest frequency of improvement was observed on tests assessing rapid spatial processing (37.5%), processing speed (33.3%), and memory (33.3%). There were no consistent predictors of improvement, but several subtest-specific findings emerged. Specifically, (a) more comorbidities were positively associated with rate of fatigue reduction (p = .04), (b) longer duration since COVID-19 illness was positively associated with rates of memory improvement (p = .02), (c) older age, male sex, and more comorbidities were positively associated with rate of improvement in reaction time (ps < .05), and (d) more assessments completed was positively associated with rates of improvements in working memory (ps < .05). Response inhibition (12.5%), simple reaction times (16.7%), and working memory (16.7%) showed the lowest rates of improvement over time. Declines in cognition were infrequent, with 4.2 - 8.3% (n = 1 to 2) declining on measures of procedural reaction time, spatial processing, inhibitory control, or working memory.
Conclusions:
At an average of >9 months following acute COVID-19 illness, we observed longitudinal improvements in cognitive fatigue as well as processing speed, memory, and spatial reasoning. Consistent predictors of recovery were not identified, although age, sex, comorbid conditions, and time since illness predicted rates of improvement in select domains. Further analyses with a larger sample size and more stringent analyses are needed to confirm and extend these findings.
Health protection refers to threats to health such as infectious diseases, environmental threats, natural hazards and threats from terrorist acts. Health protection may also overlap with action, tackling the determinants of health, especially legislative aspects such as workplace smoking bans or speed restrictions and even lifestyle choices and the health issues of ageing populations, such as increasing levels of chronic disease (which we now know may also be due to infections).
This chapter outlines the public health aspects of communicable disease control and touches on some of the other areas now included within health protection in the UK. Important health protection terms are included in the glossary.