Association between breakthrough infection with COVID-19 and Toxoplasma gondii: a cross-sectional study

Abstract

The breakthrough infection following COVID-19 vaccination has been a subject of concern recently. Evidence suggests that COVID-19 vaccine efficacy diminishes over time due to multiple factors related to the host, and vaccine. Coinfection with other pathogens was claimed earlier as a contributing cause for this phenomenon. Hence, we aimed to stratify the association of post-COVID-19 vaccination breakthrough coinfection with Toxoplasma gondii (T. gondii) and its impact on disease severity. This cross-sectional study included 330 COVID-19-vaccinated patients confirmed by RT-PCR. They were also screened for anti- T. gondii antibodies using ELISA. Toxoplasma seropositive cases’ whole blood was screened for DNA using PCR to correlate results with COVID-19 severity. Out of 330 COVID-19 vaccinated patients with breakthrough infection, 34.5% (114 patients) showed positivity for Toxoplasma IgG by ELISA, and none of the cases was IgM positive. Eleven patients (9.6%) of the IgG-positive cases were positive by PCR. Positive PCR cases correlated positively with the Toxoplasma IgG titer (P < 0.001), and the Cutoff point was 191.5. Molecular analysis of Toxoplasma and COVID-19 severity showed that 8 (72.7%), 1 (9.1%), and 2 cases (18.2%) had mild, moderate, and severe courses of the disease, respectively, with no significant correlation. Our study reported a heightened prevalence of latent toxoplasmosis among mild cases of COVID-19 breakthrough infection. Nevertheless, a discernible correlation between latent toxoplasmosis and COVID-19 severity is lacking. Hence, implementing studies on a larger scale could provide a more comprehensive comprehension of this association.

Frequency of exposure to Toxoplasma gondii in COVID-19 patients. a systematic review and meta-analysis

“…et al in Mexico revealed that 21.9% of patients with COVID-19 showed the presence of T. gondii (17). Studies by Gouda MA, et al, (20) and Hasanzadeh M, et al (22) indicated the absence of active T. gondii infection in patients with COVID-19 by IgM detection.…”

“…Disparities in the prevalence of toxoplasmosis in patients with COVID-19 in various studies can be attributed to environmental factors such as temperature, humidity, geographic regions, and also sociodemographic factors such as the age distribution of the population examined (20,32). A greater propensity for infection has been noted in areas with humid and warm climates.…”

“…The frequency of exposure to T. gondii, detected through the presence of IgG in patients with COVID-19, reached 49% (95% CI: 34-63%; 2,947 participants; 13 studies; I 2 = 98%, p < 0.01) (Fig. 2) (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). In addition, the frequency of exposure to T. gondii, detected through the presence of IgM in patients with COVID-19, reached 2% (95% CI: 0-6%; 1,302 participants; 6 studies; I 2 = 94%, p < 0.01) (Fig.…”

“…Likewise, among the 1,302 COVID-19 patients tested, 36 cases were identi ed with the presence of T. gondii by IgM detection. Finally, of the 533 patients with COVID-19 screened by PCR, 21 cases were found to have T. gondii (Table 1) (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). Considering all patients, approximately 43.26% were males and 49.41% were females.…”

“…A subgroup analysis by country was performed, which revealed that the frequency of T. gondii exposure in patients with COVID-19 in Iran reached 62% (95% CI: 37-83%; 843 participants; 5 studies; I 2 = 98%, p < 0.01) (13,15,16,19,22), while in Egypt it was 38% (95% CI: 26-52%; 1303 participants; 6 studies; I 2 = 96%, p < 0.01) (11,12,18,20,21,23) (Figure S2).…”