SARS CoV-2 infection among Healthcare Workers from different public health units in Brazil.

Understanding COVID-19 exposure differences among Healthcare Workers (HCWs) across various healthcare units is crucial for their protection and effective management of future outbreaks. However, comparative data on COVID-19 among HCWs in different healthcare units are scarce in Brazil. This study evaluated the relationship between SARS-CoV-2 infection and workplaces in HCWs from three distinct healthcare settings in Brazil. It also examined COVID-19 symptom dynamics reported by them. The cohort comprised 464 HCWs vaccinated with two doses of CoronaVac and a BNT162b2 booster from different institutions: Primary Health Care Units (PHCUs), Emergency Care Units (ECUs), and Hospitals. Participants answered a questionnaire and underwent blood collection at various time points after vaccinations. RT-PCR data and post-vaccination antibody responses were utilized as indicators of SARS-CoV-2 infection. We found that most infected HCWs worked in ECUs, where positive RT-PCR percentages were higher compared to PHCUs and Hospitals. ECUs also showed the highest seropositivity and antibody levels, especially after the first CoronaVac dose. The second dose of CoronaVac diminished the differences in the antibody levels among HCWs from ECUS, PHCUs, and Hospitals, indicating the benefit of the second dose to equalize the antibody levels between previously exposed and unexposed persons. Moreover, COVID-19 symptoms appeared to evolve over time.

Influence of age, gender, previous SARS-CoV-2 infection, and pre-existing diseases in antibody response after COVID-19 vaccination: A review.

Vaccines induce specific long-term immunological memory against pathogens, preventing the worsening of diseases. The COVID-19 health emergency has caused more than 6 million deaths and started a race for vaccine development. Antibody response to COVID-19 vaccines has been investigated primarily in healthcare workers. The heterogeneity of immune responses and the behavior of this response in particular groups were still very little explored. In this review, we discuss whether antibody responses after vaccination are influenced by age, gender, previous SARS-CoV-2 infection, or pre-existing diseases.

Dynamics of SARS-CoV-2 Antibody Response to CoronaVac followed by Booster Dose of BNT162b2 Vaccine.

We evaluated the longitudinal dynamics of antibody response to the SARS-CoV-2 vaccine CoronaVac and the effect of a booster dose of BNT162b2 vaccine. We found a robust antibody response after the second dose of CoronaVac that wanes over time. The response was recovered by BNT162b2, which boosted anti-spike antibody titers.

Dynamics of antibody response to CoronaVac vaccine.

CoronaVac was the first vaccine approved in Brazil for use in healthcare workers (HCWs). However, there is limited information about it, with little long-term evidence on post-vaccination antibody persistence. This study evaluated the antibody response to SARS-CoV-2 in 1237 HCWs after the first (1D), second dose (2D), and 6 months postvaccination (6mA2D) with CoronaVac. The seropositivity was 88% at 1D, increasing to 99.8% at 2D, but decreasing to 97.9% at 6mA2D, which was also observed at the analyzed antibody levels. Interestingly, the levels in females were higher than males, and we found a positive correlation with previous SARS-CoV-2 infection. Participants with comorbidities had lower levels suggesting the need to monitor for a potential booster dose. Our findings suggest that CoronaVac induced a robust antibody response that wanes significantly over time. Further longitudinal studies are needed to identify whether the antibodies will decline or plateau at a lower level.

A wide spectrum of neurological manifestations in pediatrics patients with the COVID-19 infection: a case series.

Neurological symptoms in COVID-19 patients can also be found in the pediatric population, but they are usually described as mild symptoms. Herein, we described a case series of four pediatric patients with severe and highly heterogeneous central and peripheral nervous system manifestations. The objective was to report neurological manifestations of COVID-19 in children and adolescents. The design is case series. The participants are four children and adolescents with confirmed COVID-19. The main outcome and measures are as follows: Clinical data were gathered from electronic medical records, and data of all neurologic symptoms were checked by a trained neurologist. We reported four pediatric patients with COVID-19 and different neurologic symptoms. Case 1 was a 16-year-old girl with a sensory and motor polyradiculopathy with RT-qPCR for COVID-19 and dengue both detected in CSF that improved after appropriate treatment. Case 2 was a 15-year-old boy with Guillain-Barre syndrome and had good response after using human immunoglobulin. Case 3 was a 5-year-old girl with acute intracranial hypertension that improved after going through lumbar puncture and using acetazolamide. Case 4 was a 2-month-old male infant with focal epileptic seizures that recovered after antiepileptic treatment. We highlight the need to consider different neurologic manifestations as part of the COVID-19 clinical spectrum.

Fatal Outcome of Chikungunya Virus Infection in Brazil.

BACKGROUND: Chikungunya virus (CHIKV) emerged in the Americas in 2013 and has caused approximately 2.1 million cases and >600 deaths. A retrospective investigation was undertaken to describe clinical, epidemiological, and viral genomic features associated with deaths caused by CHIKV in Ceará state, northeast Brazil. METHODS: Sera, cerebrospinal fluid (CSF), and tissue samples from 100 fatal cases with suspected arbovirus infection were tested for CHIKV, dengue virus (DENV), and Zika virus (ZIKV). Clinical, epidemiological, and death reports were obtained for patients with confirmed CHIKV infection. Logistic regression analysis was undertaken to identify independent factors associated with risk of death during CHIKV infection. Phylogenetic analysis was conducted using whole genomes from a subset of cases. RESULTS: Sixty-eight fatal cases had CHIKV infection confirmed by reverse-transcription quantitative polymerase chain reaction (52.9%), viral antigen (41.1%), and/or specific immunoglobulin M (63.2%). Co-detection of CHIKV with DENV was found in 22% of fatal cases, ZIKV in 2.9%, and DENV and ZIKV in 1.5%. A total of 39 CHIKV deaths presented with neurological signs and symptoms, and CHIKV-RNA was found in the CSF of 92.3% of these patients. Fatal outcomes were associated with irreversible multiple organ dysfunction syndrome. Patients with diabetes appear to die at a higher frequency during the subacute phase. Genetic analysis showed circulation of 2 CHIKV East-Central-South African (ECSA) lineages in Ceará and revealed no unique virus genomic mutation associated with fatal outcome. CONCLUSIONS: The investigation of the largest cross-sectional cohort of CHIKV deaths to date reveals that CHIKV-ECSA strains can cause death in individuals from both risk and nonrisk groups, including young adults.

Dengue Fever and Aedes aegypti in indigenous Brazilians: seroprevalence, risk factors, knowledge and practices.

OBJECTIVE: Dengue remains an important public health problem in Brazil. We estimated the associated factors of dengue seroprevalence among native Indians of the Tremembé ethnic and their knowledge about the aspects related to the presence of mosquitoes of the genus Aedes. METHODS: An analytical cross-sectional study and a prospective environmental study to monitor the trapping of mosquito eggs monthly were performed. The serological portion of the study involved indigenous people living in the village of Tapera in northeastern Brazil. Ovitraps were monitored for 12 months. RESULTS: Two hundred and ninety of 350 indigenous people (82.9%) participated in the study, with an average age of 30.2 years. The seroprevalence was 22.1% and positivity increased with age, with rates of 4.2% in children under 15 years of age, 26.8% in 15 to 59-year-olds and 42.3% in those older than 59 (CI: 2.25-15.96; P < 0.001). A higher incidence of moving to the city and the presence of underlying diseases were associated with the occurrence of dengue (P < 0.001). Four serotypes were detected, with the highest prevalence of DENV-1 (77.8%), followed by DENV-2 (70.4%), DENV-3 (14.8%) and DENV-4 (11.1%). Eggs were collected in all months of the year and in the traps located in the vicinities of the domiciles (57%). CONCLUSIONS: We present the first seroepidemiological survey of dengue conducted among indigenous populations in Brazil. This lack of studies is likely due to the great bureaucratic challenge of working with indigenous populations, which may lead to greater negligence in the health of these populations.

Death by dengue fever in a Brazilian child: a case report.

BACKGROUND: Dengue is an important worldwide public health problem, and continues to spread in Brazil. This article presents the first Brazilian case report of the death of an indigenous child by dengue fever. CASE PRESENTATION: In August 2013, a child aged 2 years and from the Tremembé ethnic group, who was previously healthy with no complaints, suddenly presented intense crying, precordial pain, and general malaise. A few minutes after these non-specific symptoms, the patient started tonic-clonic convulsions and had cyanosis, a substantial increase in body temperature to the touch, cold sudoresis, sphincter relaxation, and unconsciousness. This situation remained for 15 minutes, progressing to respiratory insufficiency, with consequent absence of peripheral pulses. Death was confirmed approximately 40 minutes after the first symptoms. An autopsy was performed using the usual techniques. Immunohistochemistry was positive for dengue, and microscopic examination indicated micro perivascular edema and cerebral hemorrhage. CONCLUSION: Considering that the death occurred during the major endemic seasonal period for dengue fever, primary clinical evidence suggestive of viral infection presenting with sudden and quick death, and positive immunohistochemistry results, the case was closed as severe dengue fever. Clinicians must consider dengue as a diagnostic hypothesis among the indigenous population in Brazil.

Occurrence of natural vertical transmission of dengue-2 and dengue-3 viruses in Aedes aegypti and Aedes albopictus in Fortaleza, Ceará, Brazil.

BACKGROUND: Aedes aegypti and Aedes albopictus perform an important role in the transmission of the dengue virus to human populations, particularly in the tropical and subtropical regions of the world. Despite a lack of understanding in relation to the maintenance of the dengue virus in nature during interepidemic periods, the vertical transmission of the dengue virus in populations of A. aegypti and A. albopictus appears to be of significance in relation to the urban scenario of Fortaleza. METHODS: From March 2007 to July 2009 collections of larvae and pupae of Aedes spp were carried out in 40 neighborhoods of Fortaleza. The collections yielded 3,417 (91%) A. aegypti mosquitoes and 336 (9%) A. albopictus mosquitoes. Only pools containing females, randomly chosen, were submitted to the following tests indirect immunofluorescence (virus isolation), RT-PCR/nested-PCR and nucleotide sequencing at the C-prM junction of the dengue virus genome. RESULTS: The tests on pool 34 (35 A. albopictus mosquitoes) revealed with presence of DENV-3, pool 35 (50 A. aegypti mosquitoes) was found to be infected with DENV-2, while pool 49 (41 A. albopictus mosquitoes) revealed the simultaneous presence of DENV-2 and DENV-3. Based on the results obtained, there was a minimum infection rate of 0.5 for A. aegypti and 9.4 for A. albopictus. The fragments of 192 bp and 152 bp related to DENV-3, obtained from pools 34 and 49, was registered in GenBank with the access codes HM130699 and JF261696, respectively. CONCLUSIONS: This study recorded the first natural evidence of the vertical transmission of the dengue virus in populations of A. aegypti and A. albopictus collected in Fortaleza, Ceará State, Brazil, opening a discuss on the epidemiological significance of this mechanism of viral transmission in the local scenario, particularly with respect to the maintenance of these viruses in nature during interepidemic periods.