Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jul;94(7):3410-3415.
doi: 10.1002/jmv.27686. Epub 2022 Mar 22.

Active surveillance and early detection of community transmission of SARS-CoV-2 Mu variant (B.1.621) in the Brazilian Amazon

Gabriella S Oliveira  1 , Luciana Silva-Flannery  2 , Juliana F Silva  2 , Charlene Siza  2 , Roberto J Esteves  3 , Barbara J Marston  2 , Juliette Morgan  3 , Mateusz Plucinski  2 , Tárcio P Roca  1 , Ana M P Silva  1 , Soraya S Pereira  4 , Juan M V Salcedo  1   5 , Dhelio B Pereira  5 , Felipe G Naveca  6 , Deusilene S Vieira Dall'Acqua  1   4 ; Brazil Investigation Team
Affiliations

Active surveillance and early detection of community transmission of SARS-CoV-2 Mu variant (B.1.621) in the Brazilian Amazon

Gabriella S Oliveira et al. J Med Virol. 2022 Jul.

Abstract

Through active surveillance and contact tracing from outpatients, we aimed to identify and characterize SARS-CoV-2 variants circulating in Porto Velho-Rondônia, a city in the Brazilian Amazon. As part of a prospective cohort, we gathered information from 2,506 individuals among COVID-19 patients and household contacts. Epidemiological data, nasopharyngeal swabs, and blood samples were collected from all participants. Nasopharyngeal swabs were tested for antigen rapid diagnostic test and reverse transcription-polymerase chain reaction (RT-PCR) followed by genomic sequencing. Blood samples underwent ELISA testing for IgA, IgG, and IgM antibody levels. From 757 specimens sequenced, three were identified as Mu variant, none of the individuals carrying this variant had a travel history in the previous 15 days before diagnosis. One case was asymptomatic and two presented mild symptoms. Two infected individuals from different households caring viruses with additional amino acid substitutions ORF7a P45L and ORF1a T1055A compared to the Mu virus reference sequence. One patient presented IgG levels. Our results highlight that genomic surveillance for SARS-CoV-2 variants can assist in detecting the emergency of SARS-CoV-2 variants in the community, before its identification in other parts of the country.

Keywords: Active surveillance; Brazilian Amazon; Mu variant; SARS-CoV-2.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Representation of the genome‐wide mutation frequency of the Mu variant identified in this study. All three cases described here had the defining mutations of the Mu strain, additionally, Cases 1 and 3 had two amino acid substitutions ORF7a P45L and ORF1a T1055A compared to the Mu variant reference sequence
Figure 2
Figure 2
Phylogenetic tree including SARS‐CoV‐2 variant virus sequences identified in Rondônia state, western Brazil, during June–August 2021 (in color): Delta (B.1.617.2, n = 3 [green]), Mu (B.1.621, n = 3 [described here, blue]), and Gamma (P.1, father [red]) lineages. For comparison, 16 sequences obtained from GISAID (www.gisaid.org) for SARS‐CoV‐2 viruses from Delta, Mu, and Gamma lineages identified in the state are shown by genetic distance using a bootstrap analysis to estimate the confidence of the branches
See this image and copyright information in PMC

References

    1. Laiton‐Donato K, Franco‐Munoz C, Alvarez‐Diaz DA, et al. Characterization of the emerging B.1.621 variant of interest of SARS‐CoV‐2. Infect Genet Evol. 2021;95:105038. 10.1016/J.MEEGID.2021.105038 - DOI - PMC - PubMed
    1. Rees‐Spear C, Muir L, Griffith SA, et al. The effect of spike mutations on SARS‐CoV‐2 neutralization. Cell Rep. 2021;34(12):108890. 10.1016/J.CELREP.2021.108890 - DOI - PMC - PubMed
    1. Davies NG, Abbott S, Barnard RC, et al. Estimated transmissibility and impact of SARS‐CoV‐2 lineage B.1.1.7 in England. Science. 2021;372(6538):283. 10.1126/science.abg3055 - DOI - PMC - PubMed
    1. Jeyanathan M, Afkhami S, Smaill F, Miller MS, Lichty BD, Xing Z. Immunological considerations for COVID‐19 vaccine strategies. Nat Rev Immunol. 2020;20(10):615‐632. 10.1038/s41577-020-00434-6 - DOI - PMC - PubMed
    1. Harvey WT, Carabelli AM, Jackson B, et al. SARS‐CoV‐2 variants, spike mutations and immune escape. Nat Rev Microbiol. 2021;19(7):409‐424. 10.1038/s41579-021-00573-0 - DOI - PMC - PubMed

Publication types

Substances

Supplementary concepts