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1.
Trends Mol Med ; 28(8): 662-680, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1931041

ABSTRACT

COVID-19 caused by SARS-CoV-2 coronavirus has been associated with severe illness in pregnant women. Furthermore, COVID-19 during pregnancy is associated with adverse fetal outcomes including preterm labor. Pregnant women were largely excluded from initial clinical trials investigating the safety and efficacy of COVID-19 vaccines; however, they have since been included as part of the routine roll-out of these vaccines. This narrative review synthesizes the evidence on the safety, immunogenicity, and effectiveness predominantly of the mRNA COVID-19 vaccines which have been most widely used in pregnant women.


Subject(s)
COVID-19 Vaccines , COVID-19 , Pregnancy Complications, Infectious , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Female , Humans , Immunogenicity, Vaccine , Infant, Newborn , Pregnancy , Pregnancy Complications, Infectious/prevention & control , SARS-CoV-2
2.
Front Immunol ; 13: 873191, 2022.
Article in English | MEDLINE | ID: covidwho-1825483

ABSTRACT

Influenza virus hemagglutinin (HA) stalk-specific antibodies have been shown to potently induce Fc-mediated effector functions which are important in protection from disease. In placebo-controlled maternal influenza (MatFlu) vaccination trials of pregnant women living with or without HIV, reduced risk of influenza illness was associated with high HA stalk antibody titers following trivalent inactivated vaccination (TIV). However, the mechanisms of immunity conferred by the HA stalk antibodies were not well understood. Here, we investigated HA stalk-specific Fc effector functions including antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent complement deposition (ADCD), and FcγRIIa and FcγRIIIa binding in response to seasonal influenza vaccination. These were measured pre- and 1-month post-vaccination in 141 HIV-uninfected women (67 TIV and 74 placebo recipients) and 119 women living with HIV (WLWH; 66 TIV and 53 placebo recipients). In contrast to HIV-uninfected women, where HA stalk-specific ADCP and FcγRIIa binding were significantly boosted, WLWH showed no increase in response to vaccination. HA stalk-specific ADCC potential and FcγRIIIa binding were not boosted regardless of HIV status but were higher in WLWH compared with HIV-uninfected women prior to vaccination. HA stalk-specific ADCD was significantly increased by vaccination in all women, but was significantly lower in the WLWH both pre- and post- vaccination. Co-ordination between HA stalk-specific ADCP and ADCD in WLWH was improved by vaccination. Fc polyfunctionality was enhanced by vaccination in HIV-uninfected women and driven by the HA stalk antibody titers. However, in the WLWH, higher pre-vaccination Fc polyfunctionality was maintained post-vaccination but was decoupled from titer. Overall, we showed differential regulation of Fc effector HA stalk responses, suggesting that HIV infection results in unique humoral immunity in response to influenza vaccination, with relevance for future strategies that aim to target the HA stalk in this population.


Subject(s)
HIV Infections , Influenza, Human , Antibodies, Viral , Female , Hemagglutinin Glycoproteins, Influenza Virus , Hemagglutinins , Humans , Influenza, Human/prevention & control , Male , Pregnancy , Vaccination
3.
Gates Open Research ; 2021.
Article in English | ProQuest Central | ID: covidwho-1835895

ABSTRACT

Background: A potential explanation for the fact that the high rate of infection of SARS-CoV-2 in South Africa did not translate into high rates of severe illness and death may be the presence of cross-reactive immunity induced by common cold coronaviruses (CCoV). Methods: We used SARS-CoV-2 peptide pools and whole virus antigen to stimulate peripheral blood mononuclear cells collected pre-2020 from South African women. Dual-colour FluoroSpot assay was used to measure interferon gamma (IFNγ) and interleukin 2 (IL2) production. Results: Among the 97 study participants, IFNγ responses were observed in 29.9% of the women and IL2 among 39.2%. Overall, 51.6% of women demonstrated response to at least one stimulant. Conclusion: We demonstrate the presence of cross-reactive immunity to SARS-CoV-2, which might have been induced by past exposure to CCoV.

4.
Vaccines (Basel) ; 10(3)2022 Mar 17.
Article in English | MEDLINE | ID: covidwho-1753697

ABSTRACT

We investigated Omicron infections among healthcare workers (HCW) presenting with symptoms of SARS-CoV-2 infection and evaluated the protective effect of vaccination or prior infection. Between 24 November and 31 December 2021, HCW in Johannesburg, South Africa, were tested for SARS-CoV-2 infection by Nucleic Acid Amplification Test (NAAT). Blood samples collected either at the symptomatic visit or in the 3 months prior, were tested for spike protein immunoglobulin G (IgG). Overall, 433 symptomatic HCW were included in the analysis, with 190 (43.9%) having an Omicron infection; 69 (16.7%) were unvaccinated and 270 (62.4%) received a single dose of the Ad26.COV.2 vaccine. There was no difference in the odds of identifying Omicron between unvaccinated and Ad26.COV.2 vaccinated HCW (adjusted odds ratio (aOR) 0.81, 95% confidence interval (CI): 0.46, 1.43). One-hundred and fifty-four (35.3%) HCW had at least one SARS-CoV-2 NAAT-confirmed prior infection; these had lower odds of Omicron infection compared with those without past infection (aOR 0.55, 95%CI: 0.36, 0.84). Anti-spike IgG concentration of 1549 binding antibody unit/mL was suggestive of significant reduction in the risk of symptomatic Omicron infection. We found high reinfection and vaccine breakthrough infection rates with the Omicron variant among HCW. Prior infection and high anti-spike IgG concentration were protective against Omicron infection.

5.
PLoS One ; 17(1): e0262179, 2022.
Article in English | MEDLINE | ID: covidwho-1636037

ABSTRACT

Comparisons of histopathological features and microbiological findings between decedents with respiratory symptoms due to SARS-CoV-2 infection or other causes, in settings with high prevalence of HIV and Mycobacterium tuberculosis (MTB) infections have not been reported. Deaths associated with a positive ante-mortem SARS-CoV-2 PCR test and/or respiratory disease symptoms at Chris Hani Baragwanath Academic Hospital in Soweto, South Africa from 15th April to 2nd November 2020, during the first wave of the South African COVID-19 epidemic, were investigated. Deceased adult patients had post-mortem minimally-invasive tissue sampling (MITS) performed to investigate for SARS-CoV-2 infection and molecular detection of putative pathogens on blood and lung samples, and histopathology examination of lung, liver and heart tissue. During the study period MITS were done in patients displaying symptoms of respiratory disease including 75 COVID-19-related deaths (COVID+) and 42 non-COVID-19-related deaths (COVID-). The prevalence of HIV-infection was lower in COVID+ (27%) than in the COVID- (64%), MTB detection was also less common among COVID+ (3% vs 13%). Lung histopathology findings showed differences between COVID+ and COVID- in the severity of the morphological appearance of Type-II pneumocytes, alveolar injury and repair initiated by SARS-CoV-2 infection. In the liver necrotising granulomatous inflammation was more common among COVID+. No differences were found in heart analyses. The prevalence of bacterial co-infections was higher in COVID+. Most indicators of respiratory distress syndrome were undifferentiated between COVID+ and COVID- except for Type-II pneumocytes. HIV or MTB infection does not appear in these data to have a meaningful correspondence with COVID-related deaths.


Subject(s)
Alveolar Epithelial Cells/pathology , COVID-19/epidemiology , COVID-19/mortality , Diabetes Mellitus/epidemiology , Hypertension/epidemiology , Pandemics , SARS-CoV-2/genetics , Adult , Aged , Autopsy , Biopsy, Large-Core Needle/methods , COVID-19/pathology , COVID-19/virology , COVID-19 Nucleic Acid Testing/methods , Comorbidity , Female , Humans , Length of Stay , Male , Middle Aged , Real-Time Polymerase Chain Reaction/methods , South Africa/epidemiology
6.
Cell ; 2022.
Article in English | EuropePMC | ID: covidwho-1601904

ABSTRACT

On the 24th November 2021 the sequence of a new SARS CoV-2 viral isolate Omicron-B.1.1.529 was announced, containing far more mutations in Spike (S) than previously reported variants. Neutralization titres of Omicron by sera from vaccinees and convalescent subjects infected with early pandemic as well as Alpha, Beta, Gamma, Delta are substantially reduced or fail to neutralize. Titres against Omicron are boosted by third vaccine doses and are high in cases both vaccinated and infected by Delta. Mutations in Omicron knock out or substantially reduce neutralization by most of a large panel of potent monoclonal antibodies and antibodies under commercial development. Omicron S has structural changes from earlier viruses, combining mutations conferring tight binding to ACE2 to unleash evolution driven by immune escape, leading to a large number of mutations in the ACE2 binding site which rebalance receptor affinity to that of early pandemic viruses. A comprehensive analysis of sera from vaccinees, convalescent patients infected previously by multiple variants and potent monoclonal antibodies from early in the COVID-19 pandemic reveals a substantial overall reduction the ability to neutralize the SARS-CoV-2 Omicron variant, which a third vaccine dose seems to ameliorate. Structural analyses of the Omicron RBD suggest a selective pressure enabling the virus bind ACE2 with increased affinity that is offset by other changes in the receptor binding motif that facilitates immune escape.

7.
Clin Infect Dis ; 73(10): 1896-1900, 2021 11 16.
Article in English | MEDLINE | ID: covidwho-1522151

ABSTRACT

From April to September 2020, we investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in a cohort of 396 healthcare workers (HCWs) from 5 departments at Chris Hani Baragwanath Hospital, South Africa. Overall, 34.6% of HCWs had polymerase chain reaction-confirmed SARS-CoV-2 infection (132.1 [95% confidence interval, 111.8-156.2] infections per 1000 person-months); an additional 27 infections were identified by serology. HCWs in the internal medicine department had the highest rate of infection (61.7%). Among polymerase chain reaction-confirmed cases, 10.4% remained asymptomatic, 30.4% were presymptomatic, and 59.3% were symptomatic.


Subject(s)
COVID-19 , SARS-CoV-2 , Cohort Studies , Health Personnel , Humans , Longitudinal Studies , South Africa/epidemiology
8.
Pediatr Infect Dis J ; 40(9): e323-e332, 2021 09 01.
Article in English | MEDLINE | ID: covidwho-1358506

ABSTRACT

BACKGROUND: Globally, very few childhood deaths have been attributed to coronavirus disease 2019 (COVID-19). We evaluated clinical, microbiologic and postmortem histopathologic findings in childhood deaths in whom severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified antemortem or postmortem. METHODS: Surveillance of childhood deaths was ongoing during the initial COVID-19 outbreak in South Africa from April 14, 2020, to August 31, 2020. All children hospitalized during this time had a SARS-CoV-2 test done as part of standard of care. Postmortem sampling included minimally invasive tissue sampling (MITS) of lung, liver and heart tissue; blood and lung samples for bacterial culture and molecular detection of viruses (including SARS-CoV-2) and bacteria. The cause of death attribution was undertaken by a multidisciplinary team and reported using World Health Organization framework for cause of death attribution. RESULTS: SARS-CoV-2 was identified on antemortem and/or postmortem sampling in 11.7% (20/171) of deceased children, including 13.2% (12/91) in whom MITS was done. Eighteen (90%) of 20 deaths with SARS-CoV-2 infection were <12 months age. COVID-19 was attributed in the causal pathway to death in 91.7% (11/12) and 87.5% (7/8) cases with and without MITS, respectively. Lung histopathologic features in COVID-19-related deaths included diffuse alveolar damage (n = 6, 54.5%), type 2 pneumocyte proliferation (n = 6, 54.5%) and hyaline membrane formation (n = 5, 36.4%). Culture-confirmed invasive bacterial disease was evident in 54.5% (6/11) of COVID-19 attributed deaths investigated with MITS. CONCLUSIONS: COVID-19 was in the causal pathway of 10.5% (18/171) of all childhood deaths under surveillance. The postmortem histopathologic features in fatal COVID-19 cases in children were consistent with reports on COVID-19 deaths in adults; although there was a high prevalence of invasive bacterial disease in the children.


Subject(s)
COVID-19/mortality , SARS-CoV-2/isolation & purification , Adolescent , COVID-19/complications , COVID-19/pathology , COVID-19/therapy , Child , Child, Preschool , Female , Gastroenteritis/complications , Humans , Infant , Infant, Newborn , Male , Respiration, Artificial , Respiratory Tract Diseases/complications , Seizures/complications , South Africa/epidemiology
9.
mBio ; 12(1)2021 01 08.
Article in English | MEDLINE | ID: covidwho-1066816

ABSTRACT

In December 2019 a new coronavirus (CoV) emerged as a human pathogen, SARS-CoV-2. There are few data on human coronavirus infections among individuals living with HIV. In this study we probed the role of pneumococcal coinfections with seasonal CoVs among children living with and without HIV hospitalized for pneumonia. We also described the prevalence and clinical manifestations of these infections. A total of 39,836 children who participated in a randomized, double-blind, placebo-controlled clinical trial on the efficacy of a 9-valent pneumococcal conjugate vaccine (PCV9) were followed for lower respiratory tract infection hospitalizations until 2 years of age. Nasopharyngeal aspirates were collected at the time of hospitalization and were screened by PCR for four seasonal CoVs. The frequency of CoV-associated pneumonia was higher in children living with HIV (19.9%) than in those without HIV (7.6%, P < 0.001). Serial CoV infections were detected in children living with HIV. The case fatality risk among children with CoV-associated pneumonia was higher in those living with HIV (30.4%) than without HIV (2.9%, P = 0.001). C-reactive protein and procalcitonin levels were elevated in 36.8% (≥40 mg/liter) and 64.7% (≥0.5 ng/ml), respectively, of the fatal cases living with HIV. Among children without HIV, there was a 64.0% (95% CI: 22.9% to 83.2%) lower incidence of CoV-associated pneumonia hospitalizations among PCV9 recipients compared to placebo recipients. These data suggest that Streptococcus pneumoniae infections might have a role in the development of pneumonia associated with endemic CoVs, that PCV may prevent pediatric CoV-associated hospitalization, and that children living with HIV with CoV infections develop more severe outcomes.IMPORTANCE SARS-CoV-2 may cause severe hospitalization, but little is known about the role of secondary bacterial infection in these severe cases, beyond the observation of high levels of reported inflammatory markers, associated with bacterial infection, such as procalcitonin. We did a secondary analysis of a double-blind randomized trial of PCV to examine its impact on human CoV infections before the pandemic. We found that both children living with and without HIV randomized to receive PCV had evidence of less hospitalization due to seasonal CoV, suggesting that pneumococcal coinfection may play a role in severe hospitalized CoV infections.


Subject(s)
AIDS-Related Opportunistic Infections/prevention & control , Coronavirus Infections/prevention & control , Pneumococcal Vaccines/administration & dosage , Pneumonia, Viral/prevention & control , Streptococcus pneumoniae/immunology , AIDS-Related Opportunistic Infections/epidemiology , AIDS-Related Opportunistic Infections/pathology , Coinfection/epidemiology , Coinfection/microbiology , Coinfection/prevention & control , Coinfection/virology , Coronavirus/classification , Coronavirus/isolation & purification , Coronavirus Infections/epidemiology , Coronavirus Infections/pathology , Follow-Up Studies , Hospitalization/statistics & numerical data , Humans , Incidence , Infant , Pneumonia, Pneumococcal/epidemiology , Pneumonia, Pneumococcal/prevention & control , Pneumonia, Viral/epidemiology , Prevalence , Randomized Controlled Trials as Topic
10.
SSRN; 2020.
Preprint | SSRN | ID: ppcovidwho-1749

ABSTRACT

Background: In December 2019 a new coronavirus (CoV) emerged as a human pathogen, SARS-CoV-2. There are few data on human coronavirus infections among individua

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