Corrigendum to "Cross-sectional analysis of students and school workers reveals a high number of asymptomatic SARS-CoV-2 infections during school reopening in Brazilian cities" [Heliyon 8 (11) (November 2022) Article e11368].

[This corrects the article DOI: 10.1016/j.heliyon.2022.e11368.].

Cross-sectional analysis of students and school workers reveals a high number of asymptomatic SARS-CoV-2 infections during school reopening in Brazilian cities.

Brazil experienced one of the most prolonged periods of school closures, and reopening could have exposed students to high rates of SARS-CoV-2 infection. However, the infection status of students and school workers at the time of the reopening of schools located in Brazilian cities is unknown. Here we evaluated viral carriage by RT-PCR and seroprevalence of anti-SARS-CoV-2 antibodies (IgM and IgG) by immunochromatography in 2259 individuals (1139 students and 1120 school workers) from 28 schools in 28 Brazilian cities. We collected the samples within 30 days after public schools reopened and before the start of vaccination campaigns. Most students (n = 421) and school workers (n = 446) had active (qRT-PCR + IgM- IgG- or qRT-PCR + IgM + IgG-/+) SARS-CoV-2 infection. Regression analysis indicated a strong association between the infection status of students and school workers. Furthermore, while 45% (n = 515) of the students and 37% (n = 415) of the school workers were neither antigen nor antibody positive in laboratory tests, 16% of the participants (169 students and 193 school workers) were oligosymptomatic, including those reinfected. These individuals presented mild symptoms such as headache, sore throat, and cough. Notably, most of the individuals were asymptomatic (83.9%). These results indicate that many SARS-CoV-2 infections in Brazilian cities during school reopening were asymptomatic. Thus, our study highlights the need to promote a coordinated public health effort to guarantee a safe educational environment while avoiding exacerbating pre-existent social inequalities in Brazil, reducing social, mental, and economic losses for students, school workers, and their families.

Low prevalence of influenza A strains with resistance markers in Brazil during 2017-2019 seasons.

The influenza A virus (IAV) is of a major public health concern as it causes annual epidemics and has the potential to cause pandemics. At present, the neuraminidase inhibitors (NAIs) are the most widely used anti-influenza drugs, but, more recently, the drug baloxavir marboxil (BXM), a polymerase inhibitor, has also been licensed in some countries. Mutations in the viral genes that encode the antiviral targets can lead to treatment resistance. Worldwide, a low prevalence of antiviral resistant strains has been reported. Despite that, this situation can change rapidly, and resistant strain surveillance is a priority. Thus, the aim of this was to evaluate Brazilian IAVs antiviral resistance from 2017 to 2019 through the identification of viral mutations associated with reduced inhibition of the drugs and by testing the susceptibility of IAV isolates to oseltamivir (OST), the most widely used NAI drug in the country. Initially, we analyzed 282 influenza A(H1N1)pdm09 and 455 A(H3N2) genetic sequences available on GISAID. The amino acid substitution (AAS) NA:S247N was detected in one A(H1N1)pdm09 strain. We also identified NA:I222V (n = 6) and NA:N329K (n = 1) in A(H3N2) strains. In addition, we performed a molecular screening for NA:H275Y in 437 A(H1N1)pdm09 samples, by pyrosequencing, which revealed a single virus harboring this mutation. Furthermore, the determination of OST IC50 values for 222 A(H1N1)pdm09 and 83 A(H3N2) isolates revealed that all isolates presented a normal susceptibility profile to the drug. Interestingly, we detected one A(H3N2) virus presenting with PA:E119D AAS. Moreover, the majority of the IAV sequences had the M2:S31N adamantanes resistant marker. In conclusion, we show a low prevalence of Brazilian IAV strains with NAI resistance markers, in accordance with what is reported worldwide, indicating that NAIs still remain an option for the treatment of influenza infections in Brazil. However, surveillance of influenza resistance should be strengthened in the country for improving the representativeness of investigated viruses and the robustness of the analysis.

Estimated SARS-CoV-2 Infection and Seroprevalence in Firefighters from a Northeastern Brazilian State: A Cross-Sectional Study.

The new coronavirus has been affecting health worldwide and essential service workers are continually exposed to this infectious agent, increasing the chance of infection and the development of the disease. Thus, this study aimed to estimate the frequency of infection and seroprevalence for SARS-CoV-2 in military firefighters in a city in Northeastern Brazil in January 2021. An observational cross-sectional study was carried out with 123 firefighters who answered a brief questionnaire to collect socio-epidemiological data and underwent RT-PCR and immunofluorescence test (IgM and IgG). The results found reveal a positive seroprevalence, with a high rate of infection in this class of workers, since they are essential service professionals who are exposed to risk due to their working hours, in addition to sharing some spaces and work materials. Besides, there were significant associations between positivity for IgG and IgM, as well as for positive RT-PCR prior to the study and the presence of IgG, with odd ratios of 3.04 and 4.9, respectively. These findings reinforce the need for immunization in this category, whose line of service hinders the adoption of distancing measures, since in many situations physical contact is inevitable.

Molecular characterization and phylogenetic analysis of Chikungunya virus during the 2016 outbreak in Sergipe, northeastern Brazil.

BACKGROUND: Chikungunya (CHIKV) is an arbovirus transmitted mainly by Aedes aegypti females. CHIKV has been highlighted as the pathogen with the greatest impact due to the high morbidity caused by the infection. In 2016, Brazil experienced an outbreak that affected almost 272 000 people. Here, we performed a molecular characterization and phylogenetic analysis of the CHIKV circulating in 2016 in the state of Sergipe, Brazil. METHODS: A partial region of the E1 gene of 16 CHIKV-positive samples from Sergipe State was amplified and sequenced. RESULTS: All sequences belonged to the East-Central-South-African genotype and three point mutations were verified. Two of them were silent mutations and one was a non-synonymous mutation, which changed lysine to threonine at position 211 in the E1 protein. This mutation was present in 81.2% of the sequences, as well as in other five Brazilian sequences from previous studies. This study found that CHIKV strains circulating in Sergipe during the 2016 outbreak belonged to two different haplotypes. CONCLUSIONS: The strains circulating in Sergipe are phylogenetically close to other Brazilian samples circulating in the northeast and southeast of the country, as well as viruses circulating during the same period in Haiti, indicating the rapid spread of these haplotypes.

Evolutionary Dynamics and Dissemination Pattern of the SARS-CoV-2 Lineage B.1.1.33 During the Early Pandemic Phase in Brazil.

A previous study demonstrates that most of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) Brazilian strains fell in three local clades that were introduced from Europe around late February 2020. Here we investigated in more detail the origin of the major and most widely disseminated SARS-CoV-2 Brazilian lineage B.1.1.33. We recovered 190 whole viral genomes collected from 13 Brazilian states from February 29 to April 31, 2020 and combined them with other B.1.1 genomes collected globally. Our genomic survey confirms that lineage B.1.1.33 is responsible for a variable fraction of the community viral transmissions in Brazilian states, ranging from 2% of all SARS-CoV-2 genomes from Pernambuco to 80% of those from Rio de Janeiro. We detected a moderate prevalence (5-18%) of lineage B.1.1.33 in some South American countries and a very low prevalence (<1%) in North America, Europe, and Oceania. Our study reveals that lineage B.1.1.33 evolved from an ancestral clade, here designated B.1.1.33-like, that carries one of the two B.1.1.33 synapomorphic mutations. The B.1.1.33-like lineage may have been introduced from Europe or arose in Brazil in early February 2020 and a few weeks later gave origin to the lineage B.1.1.33. These SARS-CoV-2 lineages probably circulated during February 2020 and reached all Brazilian regions and multiple countries around the world by mid-March, before the implementation of air travel restrictions in Brazil. Our phylodynamic analysis also indicates that public health interventions were partially effective to control the expansion of lineage B.1.1.33 in Rio de Janeiro because its median effective reproductive number (R e ) was drastically reduced by about 66% during March 2020, but failed to bring it to below one. Continuous genomic surveillance of lineage B.1.1.33 might provide valuable information about epidemic dynamics and the effectiveness of public health interventions in some Brazilian states.

Granzyme a in Chikungunya and other arboviral infections

Granzyme A (GzmA) is secreted by cytotoxic lymphocytes and has traditionally been viewed as a mediator of cell death. However, a growing body of data suggests the physiological role of GzmA is promotion of inflammation. Here, we show that GzmA is significantly elevated in the sera of chikungunya virus (CHIKV) patients and that GzmA levels correlated with viral loads and disease scores in these patients. Serum GzmA levels were also elevated in CHIKV mouse models, with NK cells the likely source. Infection of mice deficient in type I interferon responses with CHIKV, Zika virus, or dengue virus resulted in high levels of circulating GzmA. We also show that subcutaneous injection of enzymically active recombinant mouse GzmA was able to mediate inflammation, both locally at the injection site as well as at a distant site. Protease activated receptors (PARs) may represent targets for GzmA, and we show that treatment with PAR antagonist ameliorated GzmA- and CHIKV-mediated inflammation.

Granzyme a in Chikungunya and other arboviral infections

Granzyme A (GzmA) is secreted by cytotoxic lymphocytes and has traditionally been viewed as a mediator of cell death. However, a growing body of data suggests the physiological role of GzmA is promotion of inflammation. Here, we show that GzmA is significantly elevated in the sera of chikungunya virus (CHIKV) patients and that GzmA levels correlated with viral loads and disease scores in these patients. Serum GzmA levels were also elevated in CHIKV mouse models, with NK cells the likely source. Infection of mice deficient in type I interferon responses with CHIKV, Zika virus, or dengue virus resulted in high levels of circulating GzmA. We also show that subcutaneous injection of enzymically active recombinant mouse GzmA was able to mediate inflammation, both locally at the injection site as well as at a distant site. Protease activated receptors (PARs) may represent targets for GzmA, and we show that treatment with PAR antagonist ameliorated GzmA- and CHIKV-mediated inflammation.

Granzyme A in Chikungunya and Other Arboviral Infections.

Granzyme A (GzmA) is secreted by cytotoxic lymphocytes and has traditionally been viewed as a mediator of cell death. However, a growing body of data suggests the physiological role of GzmA is promotion of inflammation. Here, we show that GzmA is significantly elevated in the sera of chikungunya virus (CHIKV) patients and that GzmA levels correlated with viral loads and disease scores in these patients. Serum GzmA levels were also elevated in CHIKV mouse models, with NK cells the likely source. Infection of mice deficient in type I interferon responses with CHIKV, Zika virus, or dengue virus resulted in high levels of circulating GzmA. We also show that subcutaneous injection of enzymically active recombinant mouse GzmA was able to mediate inflammation, both locally at the injection site as well as at a distant site. Protease activated receptors (PARs) may represent targets for GzmA, and we show that treatment with PAR antagonist ameliorated GzmA- and CHIKV-mediated inflammation.

Case Report: Microcephaly in Twins due to the Zika Virus.

Recent studies have demonstrated an association between congenital Zika virus (ZIKV) infection and microcephaly; however, to date, there have been no reports on the consequences of ZIKV infection on fetuses in twin pregnancies. Herein, we reported on the first case of a monochorionic diamniotic (MCDA) twin pregnancy having ZIKV-related microcephaly. Our findings suggested that, in an MCDA twin pregnancy, the ZIKV may cause infection in both fetuses, resulting in severe abnormalities in the central nervous system due to neural cell destruction and the disruption of the normal development processes of the brain. This case report and other similar twin cases may help to understand the pathogenesis and to confirm the etiology of ZIKV as a teratogenic microorganism.

Isopropoxy-carvacrol, a derivative obtained from carvacrol, reduces acute inflammation and nociception in rodents.

Monoterpenes, compounds mainly presented in essential oils, have important pharmacological actions. Isopropoxy-carvacrol (IPC) is a derivative of the monoterpene carvacrol, and its pharmacological properties have not yet been investigated. The aim of this study was to analyse the acute anti-inflammatory and antinociceptive properties of IPC. Mice (25­30 g) and rats (150­230 g) were pre-treated (i.p.) with IPC at the doses of 10, 30 or 100 mg/kg or vehicle (Tween 80, 0.5%), 30 min. before injection of the phlogistic agents. Both the first and the second phases of formalin-induced nociception were significantly reduced by IPC (100 mg/kg). Injection of carrageenan in mice paw reduced the threshold of stimulus intensity, applied with an analgesymeter, necessary to cause paw withdrawal, which was significantly reduced by 100 mg/kg of IPC. The area under curve (0­4 hr) of rat paw oedema induced by injection of carrageenan was also significantly diminished by the administration of IPC (100 mg/kg). Administration of 12-O-tetradecanoylphorbol-13-acetate (TPA) markedly increased mice ear oedema and myeloperidase (MPO) activity. Topical co-administration of IPC (0.3­3 mg/ear) during the induction did not affect TPA-induced ear oedema, but significantly decreased MPO activity in the ears, when compared with the vehicle. In in vitro experiments, IPC reduced lipoperoxidation induced by different stimuli, showed nitric oxide scavenger activity and did not interfere with murine macrophage viability in concentrations up to 100 lg/mL. These results demonstrate that IPC exerts acute anti-inflammatory and antinociceptive activities, suggesting that it may represent an alternative in the development of new future therapeutic strategies.

The ethanol extract of the inner bark of Caesalpinia pyramidalis (Tul.) reduces urinary bladder damage during cyclophosphamide-induced cystitis in rats.

Hemorrhagic cystitis (HC) is a common side effect of cyclophosphamide therapy, which deserves new therapeutic strategies, such as those based on natural products. The ethanol extract of the inner bark of Caesalpinia pyramidalis (Tul.) (EECp) possesses anti-inflammatory, antinociceptive, and antioxidant activities as previously showed by our group. We have investigated the effect of EECp on the cyclophosphamide-induced HC. Cystitis was induced in male Wistar rats by the injection of cyclophosphamide. These animals were pretreated with EECp (100-400 mg/kg), vehicle, or mesna. Myeloperoxidase activity and malondialdehyde formation were measured in urinary bladder and other tissues. Bladder edema and histopathological alterations and serum nitric oxide metabolites concentration NOx- were also evaluated. Treatment with EECp (100-400 mg/kg) or mesna impaired the increase of myeloperoxidase activity in urinary bladder and the serum NOx- induced by cyclophosphamide but did not reduce edema in this tissue, as did mesna. Total histological score was reduced by EECp (100 mg/kg). Lung myeloperoxidase activity, which was increased by cyclophosphamide, was decreased significantly by EECp (400 mg/kg). EECp also diminished the malondialdehyde formation in bladder, lung, and spleen, although these parameters were not affected by cyclophosphamide. These results indicate that EECp reduced urinary bladder damage during cyclophosphamide-induced HC in rats.

Chemical constituents and potential anti-inflammatory activity of the essential oil from the leaves of Croton argyrophyllus

Many species from Croton genus have been used in traditional medicine and its pharmacological activities demonstrated. Croton argyrophyllus Kunth, Euphorbiaceae, is a shrub that grows in the flora of Northeastern Brazilian. The essential oil of C. argyrophyllus leaves was tested in rodents (10-100 mg/kg, p.o.) in classical models of inflammation (carrageenan-induced paw oedema and peritonitis) and its chemical constituents were determined by GC-MS/FID analysis. Nitric oxide radical-scavenging activity and lipidic peroxidation were determined to evaluate the antioxidant capacity of the essential oil (0.001-100 µg/mL). Forty-two components were identified, among them, bicyclogermacrene (14.60%) and spathulenol (8.27%) were the most abundant ones. C. argyrophyllus essential oil reduced significantly the oedema (30 and 100 mg/kg, p<0.05) and, besides, reduced the carrageenan increase in mieloperoxidase activity (10, 30, and 100 mg/kg, p<0.001). The carrageenan-induced peritonitis was significantly reduced (p<0.001) by the essential oil (10, 30, and 100 mg/kg). The essential oil (100 mg/kg) reduces the total peritoneal lavage NOx- concentration (p<0.01). Nitric oxide radical generated from sodium nitroprusside was found to be inhibited by the essential oil (p<0.001). C. argyrophyllus essential oil was able to prevent Fe2+- or Fe2+ plus H2O2-induced lipid peroxidation (p<0.001). This study suggests that the anti-inflammatory effect of the essential oil of C. argyrophyllus observed in the present study can be related, at least in part, its antioxidant capacity.

Evaluation of mechanisms involved in the antinociception of the ethanol extract from the inner bark of Caesalpinia pyramidalis in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia pyramidalis Tul. (Fabaceae) is an endemic tree of the Northeast region of Brazil, mainly in the Caatinga region. More commonly, inner bark or flowers are traditionally used to treat many painful and inflammatory processes. A common use of this plant is made by macerating a handful of its stem bark in a liter of wine or sugarcane brandy. It is drunk against stomachache, dysenteries, and diarrheas. MATERIALS AND METHODS: The ethanol extract of Caesalpinia pyramidalis inner bark was used in mice via oral route, at the doses of 10, 30, and 100mg/kg, in behavioral models of nociception and investigates some of the mechanisms underlying this effect. RESULTS: The ethanol extract (30 and 100mg/kg, P<0.001), given orally, produced dose dependent inhibition of acetic acid-induced visceral pain. The ethanol extract also caused significant and dose-dependent inhibition of capsaicin-(100mg/kg, P<0.001) and glutamate-(10, 30, and 100mg/kg, P<0.01) induced pain. The antinociception caused by the ethanol extract (30mg/kg) in the abdominal constriction test was significantly attenuated (P<0.001) by intraperitoneal treatment of mice with l-arginine (600mg/kg). CONCLUSIONS: Collectively, the present results suggest that the ethanol extract of Caesalpinia pyramidalis produced dose-related antinociception in several models of pain through mechanisms that involved both glutamatergic system and/or the l-arginine-nitric oxide pathway, supporting the folkloric usage of the plant to treat various painful processes.

Beneficial effects of the ethanol extract of Caesalpinia pyramidalis on the inflammatory response and abdominal hyperalgesia in rats with acute pancreatitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia pyramidalis Tul. (Fabaceae) is a plant found in the Northeast of Brazil that is popularly used to treat inflammation. Acute pancreatitis (AP) is an inflammatory disease for which abdominal pain is a relevant symptom. As there is no specific therapy for AP, we investigated the effect of the ethanol extract from the inner bark of C. pyramidalis (EECp) on the AP induced by common bile duct obstruction (CBDO) in rats. MATERIAL AND METHODS: AP was induced in male Wistar rats (200-250 g, n=6-8) through laparotomy and subsequent CBDO. Animals were euthanized after 6 (G6h) or 24 h (G24h) of induction. In the G6h protocol, animals were pretreated with EECp (100-400 mg/kg, p.o.) or vehicle (Tween 80; 0.2%) 1h before CBDO or sham surgery. For the G24h protocol, rats were pretreated with EECp (400mg/kg, 1h before CBDO or 1 h before and 12 h after CBDO) or vehicle. The following parameters were measured: inflammatory/oxidative (myeloperoxidase activity and malondialdehyde formation in the pancreas and lung, leukocyte counts in the blood and serum nitrate/nitrite), enzymatic (serum amylase and lipase levels) and nociceptive (abdominal hyperalgesia). RESULTS: Induction of AP by CBDO significantly increased all the parameters evaluated in both G6h and G24h protocols when compared with the respective sham group. In the G6h protocol, the EECp pretreatment (400 mg/kg) significantly reduced all these parameters, besides completely inhibiting abdominal hyperalgesia. The same profile of reduction was observed from two administrations of EECp in the G24h protocol, while one single dose of EECp was able to significantly reduce pancreatic MDA, serum lipase levels, leukocyte counts in the blood and abdominal hyperalgesia without affecting the other parameters in the G24h protocol. Furthermore, rutin was found in the EECp. CONCLUSIONS: Our results demonstrated that EECp decreases inflammation, lipoperoxidation and hyperalgesia in CBDO-induced AP, making it of interest in future approaches to treat this condition.

Carvacrol attenuates mechanical hypernociception and inflammatory response.

Carvacrol is a phenolic monoterpene present in the essential oil of the family Lamiaceae, as in the genera Origanum and Thymus. We previously reported that carvacrol is effective as an analgesic compound in various nociceptive models, probably by inhibition of peripheral mediators that could be related with its strong antioxidant effect observed in vitro. In this study, the anti-hypernociceptive activity of carvacrol was tested in mice through models of mechanical hypernociception induced by carrageenan, and the involvement of important mediators of its signaling cascade, as tumor necrosis factor-alpha (TNF-α), prostaglandin E(2) (PGE(2)), and dopamine, were assessed. We also investigated the anti-inflammatory effect of carvacrol on the model of carrageenan-induced pleurisy and mouse paw edema, and the lipopolysaccharide (LPS)-induced nitrite production in murine macrophages was observed. Systemic pretreatment with carvacrol (50 or 100 mg/kg; i.p.) inhibited the development of mechanical hypernociception and edema induced by carrageenan and TNF-α; however, no effect was observed on hypernociception induced by PGE(2) and dopamine. Besides this, carvacrol significantly decreased TNF-α levels in pleural lavage and suppressed the recruitment of leukocytes without altering the morphological profile of these cells. Carvacrol (1, 10, and 100 µg/mL) also significantly reduced (p < 0.001) the LPS-induced nitrite production in vitro and did not produce citotoxicity in the murine peritoneal macrophages in vitro. The spontaneous locomotor activity of mice was not affected by carvacrol. This study adds information about the beneficial effects of carvacrol on mechanical hypernociception and inflammation. It also indicates that this monoterpene might be potentially interesting in the development of novel tools for management and/or treatment of painful conditions, including those related to inflammatory and prooxidant states.

Antinociceptive and anti-inflammatory effects of Caesalpinia pyramidalis in rodents

Caesalpinia pyramidalis Tul., Fabaceae, is a plant with an anti-inflammatory activity that is used in folk medicine. To evaluate the mechanism of action of this plant, studies were performed on its antinociceptive and anti-inflammatory properties using an ethanol extract (EE) made from the inner bark. Oral treatment of mice with the EE (100, 200, and 400 mg/kg) decreased their acetic acid-induced abdominal writhes (p<0.001) and their formalin-induced paw licking in both the first and second phases (p<0.001). This treatment increased the reaction time of mice on the hot-plate test (400 mg/kg, p<0.05); however, it did not alter their performance on the Rotarod performance test. The carrageenan-induced paw edema in the rats and the leukocyte migration into the peritoneal cavity of the mice were also reduced by the EE given at a dose of 400 mg/kg (p<0.05). In addition, the EE (100-400 mg/kg, v.o.) did not alter the arterial pressure of non-anesthetized rats. In conclusion, the EE of C. pyramidalis shows antinociceptive and anti-inflammatory activities in rodents, supporting the usage of this plant to treat various inflammatory diseases for which it has traditionally been used.