First snap-shot meta-analysis to estimate the prevalence of serum antibodies to SARS-CoV-2 in humans

BackgroundCOVID-19 is arguably the number-one public health concern worldwide, and efforts are now escalating to control its spread. ObjectiveIn this study, we undertake a meta-analysis to estimate the global and regional anti-SARS-CoV-2 seroprevalence rates in humans and assess whether seroprevalence associates with geographical, climatic and socio-demographic factors. Data sourcesWe systematically reviewed PubMed, Scopus, Embase, medRxiv and bioRxiv for peer-reviewed articles or preprints (up to 14 August 2020). Study eligibility criteriaPopulation-based studies describing prevalence of anti-SARS-CoV-2 serum antibodies in general people. Participantsgeneral people who were tested for prevalence of anti-SARS-CoV-2 serum antibodies. InterventionsThere were no interventions. MethodsWe used random-effects model to estimate pooled seroprevalence, and then extrapolated these findings to the global population (for 2020). Sub-group and meta-regression analyses explored potential sources of heterogeneity in the data and relationships between seroprevalence and socio-demographic, geographical and climatic factors. ResultsIn total, 47 serological studies involving 399,265 people from 23 countries met the inclusion criteria. The pooled seroprevalence of SARS-CoV-2 in general people was estimated at 3.38% (95% CI, 3.05%-3.72%; 15,879/399,265). On a regional basis, we determined seroprevalence estimates of 5.27% (3.97-6.57%) in Northern Europe; 4.41% (2.20-6.61%) in Southern Europe; 4.41% (3.03- 5.79%) in North America; 3.17% (1.96-4.38%) in Western Europe; 2.02% (1.56-2.49%) in the Eastern Asia; and 1.45% (0.95-1.94%) in South America. Extrapolating to the 2020 world population, we estimated that 263,565,606 individuals had been exposed or infected with SARS-CoV-2 at the first wave of the pandemic. A significantly higher seroprevalence was related to higher income levels and human development indices, higher geographical latitudes and lower mean environmental temperatures. InterpretationThis study reinforces that SARS-CoV-2 infection is a very rapidly-spreading communicable disease and calls for routine surveys to constantly monitor temporal changes in seroprevalence around the globe.

A systematic review and meta-analysis of the prevalence of toxoplasmosis in hemodialysis patients in Iran / 한국역학회지

OBJECTIVES: Toxoplasmosis is a parasitic disease that occurs worldwide, with a wide range of complications in immunocompromised patients. This systematic review and meta-analysis was performed to evaluate the seroprevalence of Toxoplasma gondii among patients undergoing hemodialysis in Iran. METHODS: We searched English and Persian databases for studies reporting T. gondii seroprevalence in Iranian hemodialysis patients through December 31, 2017. Inclusion and exclusion criteria were applied. RESULTS: A total of 10 studies containing 1,865 participants (1,048 patients and 817 controls) met the eligibility criteria. Immunoglobulin G (IgG) antibodies against T. gondii were found in 58% (95% confidence interval [CI], 46 to 70) of hemodialysis patients and 40% (95% CI, 31 to 50) of healthy controls, while immunoglobulin M (IgM) antibodies were found in 2% (95% CI, 0 to 6) of hemodialysis patients and 0% (95% CI, 0 to 1) of healthy controls. The meta-analysis showed that hemodialysis patients were significantly more likely to be seropositive for IgG (odds ratio [OR], 2.04; 95% CI, 1.54 to 2.70; p < 0.001) and IgM (OR, 2.53; 95% CI, 1.23 to 5.22; p < 0.001) antibodies against T. gondii infection than healthy individuals. CONCLUSIONS: The current study revealed a high prevalence of T. gondii infection in hemodialysis patients. Since hemodialysis patients are immunocompromised and T. gondii can cause serious clinical complications, we recommend that periodic screenings for T. gondii infection should be incorporated into the routine clinical care of these patients.

A systematic review and meta-analysis of the prevalence of toxoplasmosis in hemodialysis patients in Iran / 한국역학회지

OBJECTIVES: Toxoplasmosis is a parasitic disease that occurs worldwide, with a wide range of complications in immunocompromised patients. This systematic review and meta-analysis was performed to evaluate the seroprevalence of Toxoplasma gondii among patients undergoing hemodialysis in Iran.METHODS: We searched English and Persian databases for studies reporting T. gondii seroprevalence in Iranian hemodialysis patients through December 31, 2017. Inclusion and exclusion criteria were applied.RESULTS: A total of 10 studies containing 1,865 participants (1,048 patients and 817 controls) met the eligibility criteria. ImmunoglobulinG (IgG) antibodies against T. gondii were found in 58% (95% confidence interval [CI], 46 to 70) of hemodialysis patients and 40% (95% CI, 31 to 50) of healthy controls, while immunoglobulin M (IgM) antibodies were found in 2% (95% CI, 0 to 6) of hemodialysis patients and 0% (95% CI, 0 to 1) of healthy controls. The meta-analysis showed that hemodialysis patients were significantly more likely to be seropositive for IgG (odds ratio [OR], 2.04; 95% CI, 1.54 to 2.70; p < 0.001) and IgM (OR, 2.53; 95% CI, 1.23 to 5.22; p < 0.001) antibodies against T. gondii infection than healthy individuals.CONCLUSIONS: The current study revealed a high prevalence of T. gondii infection in hemodialysis patients. Since hemodialysis patients are immunocompromised and T. gondii can cause serious clinical complications, we recommend that periodic screenings for T. gondii infection should be incorporated into the routine clinical care of these patients.

A systematic review and meta-analysis of the prevalence of toxoplasmosis in hemodialysis patients in Iran / 한국역학회지

OBJECTIVES@#Toxoplasmosis is a parasitic disease that occurs worldwide, with a wide range of complications in immunocompromised patients. This systematic review and meta-analysis was performed to evaluate the seroprevalence of Toxoplasma gondii among patients undergoing hemodialysis in Iran.@*METHODS@#We searched English and Persian databases for studies reporting T. gondii seroprevalence in Iranian hemodialysis patients through December 31, 2017. Inclusion and exclusion criteria were applied.@*RESULTS@#A total of 10 studies containing 1,865 participants (1,048 patients and 817 controls) met the eligibility criteria. ImmunoglobulinG (IgG) antibodies against T. gondii were found in 58% (95% confidence interval [CI], 46 to 70) of hemodialysis patients and 40% (95% CI, 31 to 50) of healthy controls, while immunoglobulin M (IgM) antibodies were found in 2% (95% CI, 0 to 6) of hemodialysis patients and 0% (95% CI, 0 to 1) of healthy controls. The meta-analysis showed that hemodialysis patients were significantly more likely to be seropositive for IgG (odds ratio [OR], 2.04; 95% CI, 1.54 to 2.70; p < 0.001) and IgM (OR, 2.53; 95% CI, 1.23 to 5.22; p < 0.001) antibodies against T. gondii infection than healthy individuals.@*CONCLUSIONS@#The current study revealed a high prevalence of T. gondii infection in hemodialysis patients. Since hemodialysis patients are immunocompromised and T. gondii can cause serious clinical complications, we recommend that periodic screenings for T. gondii infection should be incorporated into the routine clinical care of these patients.

Modulation of axonal sprouting along rostro-caudal axis of dorsal hippocampus and no neuronal survival in parahippocampal cortices by long-term post-lesion melatonin administration in lithium-pilocarpine model of temporal lobe epilepsy.

Feature outcome of hippocampus and extra-hippocampal cortices was evaluated in melatonin treated lithium-pilocarpine epileptic rats during early and chronic phases of temporal lobe epilepsy (TLE). After status epilepticus (SE) induction, 5 and 20 mg/kg melatonin were administered for 14 days or 60 days. All animals were killed 60 days post SE induction and the histological features of the rosrto-caudal axis of the dorsal hippocampus, piriform and entorhinal cortices were evaluated utilizing Nissl, Timm, and synapsin I immunoflorescent staining. Melatonin (20 mg/kg) effect on CA1 and CA3 neurons showed a region-specific pattern along the rostro-caudal axis of the dorsal hippocampus. The number of counted granular cells by melatonin (20 mg/kg) treatment increased along the rostro-caudal axis of the dorsal hippocampus in comparison to the untreated epileptic group. The density of Timm granules in the inner molecular layer of the dentate gyrus decreased significantly in all melatonin treated groups in comparison to the untreated epileptic animals. The increased density of synapsin I immunoreactivity in the outer molecular layer of the dentate gyrus of untreated epileptic rats showed a profound decrease following melatonin treatment. There was no neuronal protection in the piriform and entorhinal cortices whatever the melatonin treatment. Long-term melatonin administration as a co-adjuvant probably could reduce the post-lesion histological consequences of TLE in a region-specific pattern along the rostro-caudal axis of the dorsal hippocampus.