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1.
PLoS Pathog ; 16(4): e1008409, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32287326

RESUMO

The continual emergence of novel influenza A strains from non-human hosts requires constant vigilance and the need for ongoing research to identify strains that may pose a human public health risk. Since 1999, canine H3 influenza A viruses (CIVs) have caused many thousands or millions of respiratory infections in dogs in the United States. While no human infections with CIVs have been reported to date, these viruses could pose a zoonotic risk. In these studies, the National Institutes of Allergy and Infectious Diseases (NIAID) Centers of Excellence for Influenza Research and Surveillance (CEIRS) network collaboratively demonstrated that CIVs replicated in some primary human cells and transmitted effectively in mammalian models. While people born after 1970 had little or no pre-existing humoral immunity against CIVs, the viruses were sensitive to existing antivirals and we identified a panel of H3 cross-reactive human monoclonal antibodies (hmAbs) that could have prophylactic and/or therapeutic value. Our data predict these CIVs posed a low risk to humans. Importantly, we showed that the CEIRS network could work together to provide basic research information important for characterizing emerging influenza viruses, although there were valuable lessons learned.


Assuntos
Doenças Transmissíveis Emergentes/veterinária , Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Vírus da Influenza A/isolamento & purificação , Zoonoses/virologia , Animais , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/virologia , Doenças do Cão/transmissão , Cães , Furões , Cobaias , Humanos , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N8/classificação , Vírus da Influenza A Subtipo H3N8/genética , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Humana/transmissão , Influenza Humana/virologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Estados Unidos , Zoonoses/transmissão
2.
J Virol ; 93(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434733

RESUMO

Vaccination is the best measure of protection against influenza virus infection. Vaccine-induced antibody responses target mainly the hemagglutinin (HA) surface glycoprotein, composed of the head and the stalk domains. Recently two novel vaccine platforms have been developed for seasonal influenza vaccination: a recombinant HA vaccine produced in insect cells (Flublok) and Flucelvax, prepared from virions produced in mammalian cells. In order to compare the fine specificity of the antibodies induced by these two novel vaccine platforms, we characterized 42 Flublok-induced monoclonal antibodies (MAbs) and 38 Flucelvax-induced MAbs for avidity, cross-reactivity, and any selectivity toward the head versus the stalk domain. These studies revealed that Flublok induced a greater proportion of MAbs targeting epitopes near the receptor-binding domain on HA head (hemagglutinin inhibition-positive MAbs) than Flucelvax, while the two vaccines induced similar low frequencies of stalk-reactive MAbs. Finally, mice immunized with Flublok and Flucelvax also induced similar frequencies of stalk-reactive antibody-secreting cells, showing that HA head immunodominance is independent of immune memory bias. Collectively, our results suggest that these vaccine formulations are similarly immunogenic but differ in the preferences of the elicited antibodies toward the receptor-binding domain on the HA head.IMPORTANCE There are ongoing efforts to increase the efficacy of influenza vaccines and to promote production strategies that can rapidly respond to newly emerging viruses. It is important to understand if current alternative seasonal vaccines, such as Flublok and Flucelvax, that use alternate production strategies can induce protective influenza-specific antibodies and to evaluate what type of epitopes are targeted by distinct vaccine formulations.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/imunologia , Vacinas de Produtos Inativados/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Estudos de Coortes , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Homologia de Sequência , Vacinação , Vacinas de Produtos Inativados/administração & dosagem , Adulto Jovem
3.
J Infect Dis ; 218(7): 1054-1060, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-29762672

RESUMO

Background: Influenza A pandemics cause significant mortality and morbidity. H2N2 viruses have caused a prior pandemic, and are circulating in avian reservoirs. The age-related frequency of current population immunity to H2 viruses was evaluated. Methods: Hemagglutinin inhibition (HAI) assays against historical human and recent avian influenza A(H2N2) viruses were performed across age groups in Rochester, New York, and Hong Kong, China. The impact of existing cross-reactive HAI immunity on the effective reproduction number was modeled. Results: One hundred fifty individual sera from Rochester and 295 from Hong Kong were included. Eighty-five percent of patients born in Rochester and Hong Kong before 1968 had HAI titers ≥1:40 against A/Singapore/1/57, and >50% had titers ≥1:40 against A/Berkeley/1/68. The frequency of titers ≥1:40 to avian H2N2 A/mallard/England/727/06 and A/mallard/Netherlands/14/07 in subjects born before 1957 was 62% and 24%, respectively. There were no H2 HAI titers >1:40 in individuals born after 1968. These levels of seroprevalence reduce the initial reproduction number of A/Singapore/1/1957 or A/Berkeley/1/68 by 15%-20%. A basic reproduction number (R0) of the emerging transmissible virus <1.2 predicts a preventable pandemic. Conclusions: Population immunity to H2 viruses is insufficient to block epidemic spread of H2 virus. An H2N2 pandemic would have lower impact in those born before 1968.


Assuntos
Vírus da Influenza A Subtipo H2N2/imunologia , Influenza Humana/epidemiologia , Pandemias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Demografia , Feminino , Hong Kong/epidemiologia , Humanos , Imunidade , Lactente , Vírus da Influenza A Subtipo H2N2/isolamento & purificação , Influenza Humana/imunologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Medição de Risco , Estudos Soroepidemiológicos , Adulto Jovem
4.
J Infect Dis ; 213(6): 922-9, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26655841

RESUMO

BACKGROUND: We evaluated a candidate A/Anhui/2013(H7N9) pandemic live attenuated influenza vaccine (pLAIV) in healthy adults, and assessed the ability of 1 or 2 doses to induce immune memory. METHODS: Healthy subjects in 2 age groups (18-49 years and 50-70 years) with undetectable hemagglutination-inhibiting (HAI) antibody to H7N9 were enrolled. Younger subjects received either 1 or 2 intranasal doses of 10(7.0) fluorescent focus units of A/Anhui/1/2013 pLAIV, while older subjects received a single dose. All subjects received a single 30-µg dose of unadjuvanted, antigenically matched A/Shanghai2/2013(H7N9) pandemic inactivated influenza vaccine (pIIV) 12 weeks after their first dose of pLAIV. RESULTS: Both vaccines were well tolerated. Serum HAI antibody responses were detected in 0 of 32 younger subjects and 1 of 17 older subjects after 1 dose of pLAIV and in 2 of 16 younger subjects after a second dose. Strong serum antibody responses were detected after a single subsequent dose of pIIV that was broadly reactive against H7 influenza viruses. CONCLUSIONS: An A(H7N9) pLAIV candidate was safe in both age groups. Priming with pLAIV resulted in responses to subsequent pIIV that exceeded those seen in naive subjects in previous reports. The A(H7N9) pLAIV induces strong immune memory that can be demonstrated by exposure to subsequent antigenic challenge. CLINICAL TRIALS REGISTRATION: NCT01995695 and NCT02274545.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Administração Intranasal , Adolescente , Adulto , Idoso , Envelhecimento , Anticorpos Antivirais/sangue , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Replicação Viral/fisiologia , Eliminação de Partículas Virais , Adulto Jovem
5.
Immunology ; 148(2): 160-73, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26854888

RESUMO

Influenza vaccination does not provide 100% protection from infection, partly due to antigenic drift of the haemagglutinin (HA) protein. Low serum antibody titres increase the risk of infection. To determine whether there were additional correlates of risk, we examined the relationship between human serum immunity and antigenic variation in seasonal H3N2 influenza viruses. Seasonal H3N2 vaccine strains grown in the presence of heterogeneous human or mono-specific ferret antisera selected variants with mutations in the HA antigenic sites. Surprisingly, circulating strains infecting human subjects in the same seasons displayed mutations in the same positions, although only in one case did the change correspond to the same amino acid. Serum antibody titres were lower against both the in vitro selected and clinical isolates compared with the vaccine strains, suggesting that the mutations are relevant to vaccine failure. Antibody titres were also significantly lower in sera from infected subjects than in non-infected subjects, suggesting relatively poor responses to vaccination in the infected subjects. Collectively, the data suggest that risk from influenza infection is a result of poor response to vaccination, as well as encounter with drifted seasonal influenza virus antigenic variants. The results also show that directed selection under human immune pressure could reveal antigenic variants relevant to real-world drifted viruses, helping in annual vaccine re-formulation.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Imunidade Humoral , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Animais , Anticorpos Antivirais/sangue , Variação Antigênica , Linhagem Celular , Pré-Escolar , Estudos de Coortes , Furões , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Mutagênese Sítio-Dirigida , Estudos Prospectivos , Estações do Ano , Resultado do Tratamento , Vacinação
6.
J Virol ; 89(10): 5427-40, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25741011

RESUMO

UNLABELLED: Although a large number of immune epitopes have been identified in the influenza A virus (IAV) hemagglutinin (HA) protein using various experimental systems, it is unclear which are involved in protective immunity to natural infection in humans. We developed a data mining approach analyzing natural H1N1 human isolates to identify HA protein regions that may be targeted by the human immune system and can predict the evolution of IAV. We identified 16 amino acid sites experiencing diversifying selection during the evolution of prepandemic seasonal H1N1 strains and found that 11 sites were located in experimentally determined B-cell/antibody (Ab) epitopes, including three distinct neutralizing Caton epitopes: Sa, Sb, and Ca2 [A. J. Caton, G. G. Brownlee, J. W. Yewdell, and W. Gerhard, Cell 31:417-427, 1982, http://dx.doi.org/10.1016/0092-8674(82)90135-0]. We predicted that these diversified epitope regions would be the targets of mutation as the 2009 H1N1 pandemic (pH1N1) lineage evolves in response to the development of population-level protective immunity in humans. Using a chi-squared goodness-of-fit test, we identified 10 amino acid sites that significantly differed between the pH1N1 isolates and isolates from the recent 2012-2013 and 2013-2014 influenza seasons. Three of these sites were located in the same diversified B-cell/Ab epitope regions as identified in the analysis of prepandemic sequences, including Sa and Sb. As predicted, hemagglutination inhibition (HI) assays using human sera from subjects vaccinated with the initial pH1N1 isolate demonstrated reduced reactivity against 2013-2014 isolates. Taken together, these results suggest that diversifying selection analysis can identify key immune epitopes responsible for protective immunity to influenza virus in humans and thereby predict virus evolution. IMPORTANCE: The WHO estimates that approximately 5 to 10% of adults and 20 to 30% of children in the world are infected by influenza virus each year. While an adaptive immune response helps eliminate the virus following acute infection, the virus rapidly evolves to evade the established protective memory immune response, thus allowing for the regular seasonal cycles of influenza virus infection. The analytical approach described here, which combines an analysis of diversifying selection with an integration of immune epitope data, has allowed us to identify antigenic regions that contribute to protective immunity and are therefore the key targets of immune evasion by the virus. This information can be used to determine when sequence variations in seasonal influenza virus strains have affected regions responsible for protective immunity in order to decide when new vaccine formulations are warranted.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Adulto , Idoso , Antígenos Virais/química , Antígenos Virais/genética , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação , Pandemias , Filogenia , Seleção Genética , Adulto Jovem
7.
J Infect Dis ; 212(8): 1270-8, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25838266

RESUMO

Recent studies have shown that live attenuated influenza vaccines (LAIVs) expressing avian influenza virus hemagglutinins (HAs) prime for strong protective antibody responses to an inactivated influenza vaccine (IIV) containing the HA. To better understand this priming effect, we compared H7 HA head and stalk domain-specific B-cell responses in H7N7 LAIV-primed subjects and non-H7-primed controls after a single dose of H7N7 IIV. As previously reported, H7N7 LAIV-primed subjects but not control subjects generated strong hemagglutination-inhibiting and neutralizing antibody responses to the H7N7 IIV. Here, we found that the quantity, epitope diversity, and affinity of H7 head-specific antibodies increased rapidly in only H7N7 LAIV-primed subjects after receipt of the IIV. However, all cohorts generated a vigorous, high-affinity, stalk-specific antibody response. Consistent increases in circulating memory B-cell frequencies after receipt of the IIV reflected the specificity of high-affinity antibody production. Our findings emphasize the value of LAIVs as a vehicle for prepandemic vaccination.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Influenza A Subtipo H7N7/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Anticorpos Neutralizantes/sangue , Linfócitos B/imunologia , Estudos de Coortes , Testes de Inibição da Hemaglutinação , Humanos , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Testes de Neutralização , Vacinas Atenuadas/imunologia , Vacinas de Produtos Inativados/imunologia
8.
J Infect Dis ; 207(2): 297-305, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23148285

RESUMO

BACKGROUND: The ability of influenza vaccines to elicit CD4(+) T cells and the relationship between induction of CD4(+) T cells and vaccine-induced neutralizing antibody responses has been controversial. The emergence of swine-origin 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) provided a unique opportunity to examine responses to an influenza vaccine composed of both novel and previously encountered antigens and to probe the relationship between B-cell and T-cell responses to vaccination. METHODS: We tracked CD4(+) T-cell and antibody responses of human subjects vaccinated with monovalent subunit A(H1N1)pdm09 vaccine. The specificity and magnitude of the CD4(+) T-cell response was evaluated using cytokine enzyme-linked immunosorbent spot assays in conjugation with peptide pools representing distinct influenza virus proteins. RESULTS: Our studies revealed that vaccination induced readily detectable CD4(+) T cells specific for conserved portions of hemagglutinin (HA) and the internal viral proteins. Interestingly, expansion of HA-specific CD4(+) T cells was most tightly correlated with the antibody response. CONCLUSIONS: These results indicate that CD4(+) T-cell expansion may be a limiting factor in development of neutralizing antibody responses to pandemic influenza vaccines and suggest that approaches to facilitate CD4(+) T-cell recruitment may increase the neutralizing antibody produced in response to vaccines against novel influenza strains.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linfócitos T CD4-Positivos/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Epitopos Imunodominantes/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Pandemias , Valor Preditivo dos Testes , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
9.
Microbiol Spectr ; 11(4): e0472822, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37318331

RESUMO

Due to antigenic drift and shift of influenza A viruses (IAV) and the tendency to elicit predominantly strain-specific antibodies, humanity remains susceptible to new strains of seasonal IAV and is at risk from viruses with pandemic potential for which limited or no immunity may exist. The genetic drift of H3N2 IAV is specifically pronounced, resulting in two distinct clades since 2014. Here, we demonstrate that immunization with a seasonal inactivated influenza vaccine (IIV) results in increased levels of H3N2 IAV-specific serum antibodies against hemagglutinin (HA) and neuraminidase (NA). Detailed analysis of the H3N2 B cell response indicated expansion of H3N2-specific peripheral blood plasmablasts 7 days after IIV immunization which expressed monoclonal antibodies (MAbs) with broad and potent antiviral activity against many H3N2 IAV strains as well as prophylactic and therapeutic activity in mice. These H3N2-specific B cell clonal lineages persisted in CD138+ long-lived bone marrow plasma cells. These results demonstrate that IIV-induced H3N2 human MAbs can protect and treat influenza virus infection in vivo and suggest that IIV can induce a subset of IAV H3N2-specific B cells with broad protective potential, a feature that warrants further study for universal influenza vaccine development. IMPORTANCE Influenza A virus (IAV) infections continue to cause substantial morbidity and mortality despite the availability of seasonal vaccines. The extensive genetic variability in seasonal and potentially pandemic influenza strains necessitates new vaccine strategies that can induce universal protection by focusing the immune response on generating protective antibodies against conserved targets within the influenza virus hemagglutinin and neuraminidase proteins. We have demonstrated that seasonal immunization with inactivated influenza vaccine (IIV) stimulates H3N2-specific monoclonal antibodies in humans that are broad and potent in their neutralization of virus in vitro. These antibodies also provide protection from H3N2 IAV in a mouse model of infection. Furthermore, they persist in the bone marrow, where they are expressed by long-lived antibody-producing plasma cells. This significantly demonstrates that seasonal IIV can induce a subset of H3N2-specific B cells with broad protective potential, a process that if further studied and enhanced could aid in the development of a universal influenza vaccine.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Humanos , Animais , Camundongos , Influenza Humana/prevenção & controle , Vacinas contra Influenza/genética , Hemaglutininas , Vírus da Influenza A Subtipo H3N2/genética , Neuraminidase , Anticorpos Monoclonais , Vírus da Influenza A Subtipo H1N1/genética , Anticorpos Antivirais , Vírus da Influenza A/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
10.
Oncologist ; 17(1): 125-34, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22240540

RESUMO

BACKGROUND: The immune response of patients who have cancer, who may be receiving immunosuppressive therapy, is generally considered to be decreased. This study aimed to evaluate the immune response of cancer patients to the 2009 influenza A (H1N1) vaccine. PATIENTS AND METHODS: We conducted a prospective single site study comparing the immune response after H1N1 vaccination of healthy controls (group A), patients who had solid tumors and were taking myelosuppressive chemotherapy (group B), patients who had solid tumors and were taking nonmyelosuppressive or no treatment (group C), and patients who had hematologic malignancies (group D). RESULTS: At 2-6 weeks after vaccination, seroconversion was observed in 80.0% of group A (95% confidence interval [CI], 65.0%-89.7%), 72.2% of group B (95% CI, 55.9%-84.3%), 87.0% of group C (95% CI, 72.2%-94.7%), and 75.0% of group D (95% CI, 52.8%-89.2%) (p = NS). The geometric mean titer ratio, that is, geometric mean factor increase in antibody titer after vaccination, was 12.6 (95% CI, 7.9-19.9), 12.7 (95% CI, 7.3-22.1), 23.0 (95% CI, 13.9-38.2), and 12.1 (95% CI, 5.3-27.9) (p = NS), and the seroprotection rates were 95.5% (95% CI, 84.0%-99.6%), 79.0% (95% CI, 63.4%-89.2%), 90.5% (95% CI, 77.4%-96.8%), and 90.0% (95% CI, 71%-98.7%) in the corresponding groups (p = NS). Immune responses were robust regardless of malignancy, or time intervals between the use of myelosuppressive or immunosuppressive medications and vaccination. No participants developed clinical H1N1 infection. CONCLUSION: Cancer patients, whether taking myelosuppressive chemotherapy or not, are able to generate an immune response to the H1N1 vaccine similar to that of healthy controls.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Neoplasias/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Estudos Prospectivos
11.
JAMA Pediatr ; 176(2): 159-168, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34757387

RESUMO

Importance: Long-term effect of parental COVID-19 infection vs vaccination on human milk antibody composition and functional activity remains unclear. Objective: To compare temporal IgA and IgG response in human milk and microneutralization activity against SARS-CoV-2 between lactating parents with infection and vaccinated lactating parents out to 90 days after infection or vaccination. Design, Setting, and Participants: Convenience sampling observational cohort (recruited July to December 2020) of lactating parents with infection with human milk samples collected at days 0 (within 14 days of diagnosis), 3, 7, 10, 28, and 90. The observational cohort included vaccinated lactating parents with human milk collected prevaccination, 18 days after the first dose, and 18 and 90 days after the second dose. Exposures: COVID-19 infection diagnosed by polymerase chain reaction within 14 days of consent or receipt of messenger RNA (mRNA) COVID-19 vaccine (BNT162b2 or mRNA-1273). Main Outcomes and Measures: Human milk anti-SARS-CoV-2 receptor-binding domain IgA and IgG and microneutralization activity against live SARS-CoV-2 virus. Results: Of 77 individuals, 47 (61.0%) were in the infection group (mean [SD] age, 29.9 [4.4] years), and 30 (39.0%) were in the vaccinated group (mean [SD] age, 33.0 [3.4] years; P = .002). The mean (SD) age of infants in the infection and vaccinated group were 3.1 (2.2) months and 7.5 (5.2) months, respectively (P < .001). Infection was associated with a variable human milk IgA and IgG receptor-binding domain-specific antibody response over time that was classified into different temporal patterns: upward trend and level trend (33 of 45 participants [73%]) and low/no response (12 of 45 participants [27%]). Infection was associated with a robust and quick IgA response in human milk that was stable out to 90 days after diagnosis. Vaccination was associated with a more uniform IgG-dominant response with concentrations increasing after each vaccine dose and beginning to decline by 90 days after the second dose. Vaccination was associated with increased human milk IgA after the first dose only (mean [SD] increase, 31.5 [32.6] antibody units). Human milk collected after infection and vaccination exhibited microneutralization activity. Microneutralization activity increased throughout time in the vaccine group only (median [IQR], 2.2 [0] before vaccine vs 10 [4.0] after the first dose; P = .003) but was higher in the infection group (median [IQR], 20 [67] at day 28) vs the vaccination group after the first-dose human milk samples (P = .002). Both IgA and non-IgA (IgG-containing) fractions of human milk from both participants with infection and those who were vaccinated exhibited microneutralization activity against SARS-CoV-2. Conclusions and Relevance: In this cohort study of a convenience sample of lactating parents, the pattern of IgA and IgG antibodies in human milk differed between COVID-19 infection vs mRNA vaccination out to 90 days. While infection was associated with a highly variable IgA-dominant response and vaccination was associated with an IgG-dominant response, both were associated with having human milk that exhibited neutralization activity against live SARS-CoV-2 virus.


Assuntos
Anticorpos Neutralizantes/sangue , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Leite Humano/imunologia , SARS-CoV-2/imunologia , Adulto , Estudos de Coortes , Feminino , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Lactente , Lactação , Masculino
12.
Pathogens ; 11(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35215130

RESUMO

Infection with the ß-coronavirus SARS-CoV-2 typically generates strong virus-specific antibody production. Antibody responses against novel features of SARS-CoV-2 proteins require naïve B cell activation, but there is a growing appreciation that conserved regions are recognized by pre-existing memory B cells (MBCs) generated by endemic coronaviruses. The current study investigated the role of pre-existing cross-reactive coronavirus memory in the antibody response to the viral spike (S) and nucleocapsid (N) proteins following SARS-CoV-2 infection. The breadth of reactivity of circulating antibodies, plasmablasts, and MBCs was analyzed. Acutely infected subjects generated strong IgG responses to the S protein, including the novel receptor binding domain, the conserved S2 region, and to the N protein. The response included reactivity to the S of endemic ß-coronaviruses and, interestingly, to the N of an endemic α-coronavirus. Both mild and severe infection expanded IgG MBC populations reactive to the S of SARS-CoV-2 and endemic ß-coronaviruses. Avidity of S-reactive IgG antibodies and MBCs increased after infection. Overall, findings indicate that the response to the S and N of SARS-CoV-2 involves pre-existing MBC activation and adaptation to novel features of the proteins, along with the potential of imprinting to shape the response to SARS-CoV-2 infection.

13.
Viruses ; 13(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477472

RESUMO

Influenza A Viruses (IAV) in domestic swine (IAV-S) are associated with sporadic zoonotic transmission at the human-animal interface. Previous pandemic IAVs originated from animals, which emphasizes the importance of characterizing human immunity against the increasingly diverse IAV-S. We analyzed serum samples from healthy human donors (n = 153) using hemagglutination-inhibition (HAI) assay to assess existing serologic protection against a panel of contemporary IAV-S isolated from swine in the United States (n = 11). Age-specific seroprotection rates (SPR), which are the proportion of individuals with HAI ≥ 1:40, corresponded with lower or moderate pandemic risk classifications for the multiple IAV-S examined (one H1-δ1, one H1-δ2, three H3-IVA, one H3-IVB, one H3-IVF). Individuals born between 2004 and 2013 had SPRs of 0% for the five classified H3 subtype IAV-S, indicating youth may be particularly predisposed to infection with these viruses. Expansion of existing immunologic gaps over time could increase likelihood of future IAV-S spillover to humans and facilitate subsequent sustained human-to-human transmission resulting in disease outbreaks with pandemic potential.


Assuntos
Vírus da Influenza A/imunologia , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia , Adulto , Idoso , Animais , Feminino , Humanos , Vírus da Influenza A/classificação , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Testes Sorológicos , Suínos , Doenças dos Suínos/virologia , Estados Unidos/epidemiologia
14.
mBio ; 12(1)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563823

RESUMO

Whether mother-to-infant SARS-CoV-2 transmission can occur during breastfeeding and, if so, whether the benefits of breastfeeding outweigh this risk during maternal COVID-19 illness remain important questions. Using RT-qPCR, we did not detect SARS-CoV-2 RNA in any milk sample (n = 37) collected from 18 women following COVID-19 diagnosis. Although we detected evidence of viral RNA on 8 out of 70 breast skin swabs, only one was considered a conclusive positive result. In contrast, 76% of the milk samples collected from women with COVID-19 contained SARS-CoV-2-specific IgA, and 80% had SARS-CoV-2-specific IgG. In addition, 62% of the milk samples were able to neutralize SARS-CoV-2 infectivity in vitro, whereas milk samples collected prior to the COVID-19 pandemic were unable to do so. Taken together, our data do not support mother-to-infant transmission of SARS-CoV-2 via milk. Importantly, milk produced by infected mothers is a beneficial source of anti-SARS-CoV-2 IgA and IgG and neutralizes SARS-CoV-2 activity. These results support recommendations to continue breastfeeding during mild-to-moderate maternal COVID-19 illness.IMPORTANCE Results from prior studies assaying human milk for the presence of SARS-CoV-2, the causative virus of COVID-19, have suggested milk may act as a potential vehicle for mother-to-child transmission. Most previous studies are limited because they followed only a few participants, were cross-sectional, and/or failed to report how milk was collected and/or analyzed. As such, considerable uncertainty remains regarding whether human milk is capable of transmitting SARS-CoV-2 from mother to child. Here, we report that repeated milk samples collected from 18 women following COVID-19 diagnosis did not contain SARS-CoV-2 RNA; however, risk of transmission via breast skin should be further evaluated. Importantly, we found that milk produced by infected mothers is a source of anti-SARS-CoV-2 IgA and IgG and neutralizes SARS-CoV-2 activity. These results support recommendations to continue breastfeeding during mild-to-moderate maternal COVID-19 illness as milk likely provides specific immunologic benefits to infants.


Assuntos
Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , COVID-19/imunologia , Leite Humano/imunologia , Complicações Infecciosas na Gravidez/imunologia , SARS-CoV-2/imunologia , Adulto , Mama/virologia , Aleitamento Materno , COVID-19/transmissão , COVID-19/virologia , Feminino , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Masculino , Leite Humano/virologia , Mães , Gravidez , Complicações Infecciosas na Gravidez/virologia , RNA Viral/isolamento & purificação , SARS-CoV-2/isolamento & purificação
15.
Cogn Behav Ther ; 39(3): 173-87, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20485997

RESUMO

The provision of mental health services over the Internet is becoming increasingly commonplace as new technologies continue to develop. Evidence in support of the efficacy of many such interventions is accumulating. Given the potential global reach of Internet-based psychological services, the authors examine ethical issues relating to this growing area of practice through the lens of the Universal Declaration of Ethical Principles for Psychologists (International Union of Psychological Science, 2008). They also raise issues relating to potential liability risks and offer recommendations intended to guide mental health practitioners who are considering involvement in the provision of Internet-based services.


Assuntos
Internet/estatística & dados numéricos , Serviços de Saúde Mental/ética , Serviços de Saúde Mental/legislação & jurisprudência , Psicoterapia/ética , Psicoterapia/legislação & jurisprudência , Humanos , Cooperação Internacional , Internet/ética , Internet/legislação & jurisprudência , Guias de Prática Clínica como Assunto
16.
medRxiv ; 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32995804

RESUMO

Background: It is not known whether SARS-CoV-2 can be transmitted from mother to infant during breastfeeding, and if so whether the benefits of breastfeeding outweigh this risk. This study was designed to evaluate 1) if SARS-CoV-2 RNA can be detected in milk and on the breast of infected women, 2) concentrations of milk-borne anti-SARS-CoV-2 antibodies, and 3) the capacity of milk to neutralize SARS-CoV-2 infectivity. Methods: We collected 37 milk samples and 70 breast swabs (before and after breast washing) from 18 women recently diagnosed with COVID-19. Samples were analyzed for SARS-CoV-2 RNA using RT-qPCR. Milk was also analyzed for IgA and IgG specific for the nucleocapsid protein, receptor binding domain (RBD), S2 subunit of the spike protein of SARS-CoV-2, as well as 2 seasonal coronaviruses using ELISA; and for its ability to neutralize SARS-CoV-2. Results: We did not detect SARS-CoV-2 RNA in any milk sample. In contrast, SARS-CoV-2 RNA was detected on several breast swabs, although only one was considered conclusive. All milk contained SARS-CoV-2-specific IgA and IgG, and levels of anti-RBD IgA correlated with SARS-CoV-2 neutralization. Strong correlations between levels of IgA and IgG to SARS-CoV-2 and seasonal coronaviruses were noted. Conclusions: Our data do not support maternal-to-child transmission of SARS-CoV-2 via milk; however, risk of transmission via breast skin should be further evaluated. Importantly, milk produced by infected mothers is a source of anti-SARS-CoV-2 IgA and IgG and neutralizes SARS-CoV-2 activity. These results support recommendations to continue breastfeeding during mild-to-moderate maternal COVID-19 illness.

17.
Gerontology ; 55(4): 460-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19468202

RESUMO

BACKGROUND: Consistent with fear-avoidance models of falling and pain, past research has demonstrated that, among adults living in the community, excessive fear of falling and fear of pain result in activity restriction and predict functional outcomes including falls (possibly because self-imposed activity restriction, due to fear of pain or falling, can lead to muscular decline and deconditioning). Among seniors with dementia, who rely on others for their care, decisions concerning activity restrictions are made by caregivers. As such, caregivers' fear about the possibility of care recipient falls and pain is important to examine. OBJECTIVE: In this investigation of patients with dementia, our goal was to conduct a longitudinal investigation of the relationship between professional caregivers' fears (about the possibility that care recipients will experience falls and pain) with long-term care (LTC) resident functional ability and falls. METHODS: For the purposes of our 3-month longitudinal study, nurses' and special care aides' fears that specific residents might experience pain and falls were examined. Resident functional ability was assessed, based on an established and well-validated caregiver-administered questionnaire, both before and after the 3-month period. Falls and fall-related injuries sustained by residents were recorded. RESULTS: After controlling for physical risk factors for falling and functional ability at the beginning of the study, caregiver fears that residents might experience pain or falls were found to be predictive of restraint/restriction use. In turn, the use of restraints/restrictions was found to be predictive of future functional ability of residents with dementia (after controlling for functional ability at the beginning of the study) and injurious falls (after controlling for physical risk factors for falling). CONCLUSIONS: This is the first study to apply a modified fear-avoidance model of falls and pain to seniors with dementia who reside in LTC facilities. Our results demonstrate the importance of considering caregiver fears concerning falls and pain, when developing programs designed to optimize the use of physical restrictions (to prevent falls and minimize functional decline) in LTC facilities.


Assuntos
Acidentes por Quedas , Envelhecimento/fisiologia , Envelhecimento/psicologia , Cuidadores/psicologia , Medo , Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Demência/enfermagem , Demência/fisiopatologia , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Assistência de Longa Duração , Masculino , Modelos Psicológicos , Inquéritos e Questionários
19.
Disabil Rehabil ; 38(11): 1041-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26474116

RESUMO

PURPOSE: The purpose of this study was to determine whether providing fall risk information to long-term care (LTC) nurses affects restraint use, activities of daily living (ADL), falls, and nurse fears about patient falls. METHODS: One-hundred and fifty LTC residents were randomized to a fall risk assessment intervention or care-as-usual group. Hypotheses were tested using analyses of variance and path analyses. RESULTS: Restraint use was associated with lower ADL scores. In the intervention group, there ceased to be significant relationships between nurse fears about falls and patient falls (after controlling for actual patient risk; post-intervention, nurse fears about falls were based on realistic appraisals), and between fears and restraints (i.e. unjustified nurse fears became less likely to lead to unjustified restraint use). No group differences in falls were identified. CONCLUSION: Despite a lack of group differences in falls, results show initial promise in potentially impacting resident care. Increasing intervention intensity may lead to fall reductions in future research. IMPLICATIONS FOR REHABILITATION: Given the high prevalence rates of falls in LTC and associated injuries, prevention programs are important. Nurse fears about patient falls may impact upon restraint use which, when excessive, can interfere with the patient's ability to perform ADL. Excessive restraint use, due to unjustified nurse fears, could also lead to falls. Providing accurate, concise information to nursing staff about patient fall risk may aid in reducing the association between unjustified nurse fears and the resulting restraint use that can have potential negative consequences.


Assuntos
Acidentes por Quedas/prevenção & controle , Instituição de Longa Permanência para Idosos , Enfermeiras e Enfermeiros/psicologia , Casas de Saúde , Restrição Física , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Feminino , Avaliação Geriátrica/métodos , Enfermagem Geriátrica/métodos , Humanos , Assistência de Longa Duração/métodos , Masculino , Avaliação em Enfermagem/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde , Restrição Física/métodos , Restrição Física/estatística & dados numéricos , Medição de Risco/métodos , Fatores de Risco
20.
Am J Infect Control ; 32(8): 445-50, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15573050

RESUMO

BACKGROUND: Urinary tract infections (UTIs) are the most common nosocomial infection experienced by patients in United States hospitals and are responsible for significant morbidity and excess hospital costs. The purpose of this study was to determine the efficacy of a silver alloy, hydrogel-coated, urinary catheter in the prevention of catheter-associated UTI, to assess the cost effectiveness of the coated catheter, and to test for the emergence of silver-resistance in urinary microbial isolates. METHODS: A 2-year prospective surveillance study in 10 patient care units was conducted to determine the rate of catheter-associated UTI. Historic control data was utilized to assess the effect of the coated catheter. A cost-effectiveness analysis was conducted using a range of cost estimates. Silver susceptibility was determined for microbes responsible for catheter-associated UTI. RESULTS: Data were analyzed using a Poisson regression model. The rate of catheter-associated UTI fell from 6.13/1000 catheter-days during the period 1999-2000 to 2.62/1000 catheter-days during 2001-2002 ( P = .002). Calculated cost savings varied widely. Modest savings were achieved at the realistic lower cost estimates. No silver-resistant microbes were recovered in the susceptibility tests. CONCLUSIONS: The introduction of a silver alloy, hydrogel-coated urinary catheter was associated with a significant decline in nosocomial UTI and cost savings over the range of cost estimates. Silver-resistant urinary pathogens were not recovered from patients experiencing catheter-associated UTI during the study period.


Assuntos
Prata/uso terapêutico , Cateterismo Urinário/instrumentação , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Cateteres de Demora , Análise Custo-Benefício , Infecção Hospitalar/economia , Infecção Hospitalar/prevenção & controle , Farmacorresistência Bacteriana , Desenho de Equipamento , Custos Hospitalares , Humanos , Estudos Prospectivos , Cateterismo Urinário/efeitos adversos , Cateterismo Urinário/economia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Infecções Urinárias/prevenção & controle
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