key: cord-0858045-wmofyeqx
authors: Remes-Troche, J. M.; Ramos-de-la-Medina, A.; Manriquez-Reyes, M.; Martinez-Perez Maldonado, L.; Solis-Gonzalez, M. A.; Hernandez-Flores, K.; Vivanco-Cid, H.
title: Prevalence of SARS-CoV-2 IgG antibodies in a population from Veracruz (Southeastern Mexico).
date: 2020-10-21
journal: nan
DOI: 10.1101/2020.10.19.20215558
sha: 596feeb710db4a71d0f5bac84a3eab5f9c2b2e22
doc_id: 858045
cord_uid: wmofyeqx

Introduction/Aim: Recent studies have shown that seroprevalence is quite variable depending on the country, the population and the time of the pandemic in which the serological tests are performed. Here, we investigated the prevalence of IgG antibodies against SARS-CoV-2 in a population living in Veracruz City, Mexico. Methods: From of June 1 to July 31, 2020, the consecutive adult patients that attended 2 ambulatory diagnostic private practice centers for testing were included. Samples were run on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG assay. The main outcome was seroprevalence. Demographics, previous infection to SARS-CoV-2 (according to a previous positive polymerase-chain reaction nasopharyngeal swab), self-suspicious of virus of infection (according to have in the previous 4 weeks either fever, headache, respiratory symptoms but not a confirmatory PCR) or no having symptoms were also evaluated. Results: A total of 2174 subjects were tested, included 53.6% women (mean age 41.8, range 18-98 years). One thousand and forty-one (52.5%) subjects were asymptomatic, 722 (33.2%) had suspicious of infection and 311 (14.3%) had previous infection. Overall, 642 of 2174 (29.5% [95% CI 27.59%-31.47%]) of our population were seropositive. Seropositivity among groups was 21.3% in asymptomatic, 23.4% in self-suspicious patients and 73.9% in previous infection patients. Conclusions: We found one of the highest seroprevalences reported for SARS-CoV-2 worldwide in asymptomatic subjects (21.3%) as well in subjects with self-suspicious of COVID-19 (23.4%). The number of infected subjects in our population is not encouraging and it should be interpreted with caution.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted October 21, 2020. . https://doi.org/10.1101/2020.10.19.20215558 doi: medRxiv preprint Abstract Introduction/Aim: Recent studies have shown that seroprevalence is quite variable depending on the country, the population and the time of the pandemic in which the serological tests are performed. Here, we investigated the prevalence of IgG antibodies against SARS-CoV-2 in a population living in Veracruz City, México.

Methods: From of June 1 to July 31, 2020, the consecutive adult patients (age ≥ 18 years) that attended 2 ambulatory diagnostic private practice centers for testing were included. Samples were run on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG assay. The main outcome was seroprevalence. Demographics, previous infection to SARS-CoV-2 (according to a previous positive polymerase-chain reaction nasopharyngeal swab), self-suspicious of virus of infection (according to have in the previous 4 weeks either fever, headache, respiratory symptoms but not a confirmatory PCR) or no having symptoms were also evaluated.

A total of 2174 subjects were tested, included 53.6% women (mean age 41.8±15.17 years, range 18-98 years). One thousand and forty-one (52.5%) subjects were asymptomatic, 722 (33.2%) had suspicious of infection and 311 (14.3%) had previous infection. Overall, 642 of 2174 (29.5% [95% CI 27.59%-31.47%]) of our population were seropositive. Seropositivity among groups was 21.3% in asymptomatic, 23.4% in selfsuspicious patients and 73.9% in previous infection patients.

We found one of the highest seroprevalences reported for SARS-CoV-2 worldwide in asymptomatic subjects (21.3%) as well in subjects with self-suspicious of COVID-19 (23.4%). The number of infected subjects in our population is not encouraging and it should be interpreted with caution.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted October 21, 2020. Here, we investigated the prevalence of IgG antibodies against SARS-CoV-2and associations with demographics, previous SARS-CoV-2 infection or suspicion of virus exposure, as well in asymptomatic subjects.

From of June 1 to July 31, 2020, the consecutive adult patients (age ≥ 18 years) that attended 2 ambulatory diagnostic private practice centers for testing were included.

Samples were run on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG assay. The main outcome was seroprevalence. Seroprevalence with 95% confidence interval was calculated by the exact binomial technique. Demographics, previous infection to SARS-CoV-2 (according to a previous positive polymerase-chain reaction nasopharyngeal swab), self-suspicious of virus of infection (according to have in the previous 4 weeks either fever, headache, respiratory symptoms but not a confirmatory PCR) or no having symptoms were also evaluated. Associations among seroprevalence and . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted October 21, 2020. 

The number of infected subjects in our Mexican population is not encouraging and it should be interpreted with caution. Although some might think that we can be closer to the "so-called" herd immunity, on the other hand it could also make us think that in the case of reinfection our situation would not be so promising, since it be also higher. We fully understand that the true seroprevalence to SARS-CoV-2 is difficult to estimate at this point in the pandemic and with current essays.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted October 21, 2020. . https://doi.org/10.1101/2020.10.19.20215558 doi: medRxiv preprint Our study has obvious limitations. Selection bias is likely. The estimated prevalence may be biased due to symptomatic individuals and their family members may have been more likely to participate. Prevalence estimates could change with new information on the accuracy of test kits used. Also, the study was limited to our region of our county.

Serologic testing in other locations is warranted to track the progress of the epidemic in the whole country. . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)

The copyright holder for this preprint this version posted October 21, 2020. 

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Prevalence of SARS-CoV-2 Antibodies in Health Care Personnel in the New York City Area

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted October 21, 2020. . https://doi.org/10.1101/2020.10.19.20215558 doi: medRxiv preprint