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2.
Clin Infect Dis ; 77(4): 560-564, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37036397

RESUMEN

In a randomized clinical trial, we compare early neutralizing antibody responses after boosting with bivalent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA) vaccines based on either BA.1 or BA.4/BA.5 Omicron spike protein combined with wild-type spike. Responses against SARS-CoV-2 variants exhibited the greatest reduction in titers against currently circulating Omicron subvariants for both bivalent vaccines.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , SARS-CoV-2/genética , Anticuerpos Neutralizantes , Vacunas Combinadas , Anticuerpos Antivirales
3.
Rev Chilena Infectol ; 32(2): 175-80, 2015 Apr.
Artículo en Español | MEDLINE | ID: mdl-26065450

RESUMEN

BACKGROUND: Respiratory infection caused by Pneumocystis jiroveci is a common opportunistic infection in patients with human immunodeficiency virus (HIV) with CD4 counts < 200 cells/mm(3). However, it has also been reported in patients with other causes of immunosuppression. OBJECTIVES: To compare the characteristics, severity and mortality of respiratory infection by P. jiroveci in patients with and without HIV infection. METHODS: Retrospective cohort follow-up of adult patients admitted to our hospital with infection by P. jiroveci since 2006 to 2013. RESULTS: We included 82 patients with respiratory infection by P. jiroveci of which 55% (45) were not infected with HIV. In this group, 68.8% (31) had diagnosis of cancer and 20% (9) received solid-organ transplant. 57.9% (26) were hospitalized in an intensive care unit. 42.2% (19) suffered multiple organ failure (MOF), 46.7% (21) required mechanical ventilation (MV) and 40.9% (18) inotropic drugs. Mortality was 33.3% (15). Statistically significant differences were observed between groups in age (p < 0.001), requirement of MV (p < 0.001) inotropic drugs (p 0.001) and MOF (p < 0.001). Mortality was higher in the HIV-positive group, reaching statistical significance (p 0.007). CONCLUSION: Pneumocystis pneumonia mortality was higher in patients without HIV, who suffered more complications and progression to respiratory failure with MOF.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Pneumocystis carinii , Neumonía por Pneumocystis/inmunología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/mortalidad , Adulto , Estudios de Cohortes , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Neumonía por Pneumocystis/diagnóstico , Neumonía por Pneumocystis/mortalidad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
4.
Vaccines (Basel) ; 11(6)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37376456

RESUMEN

People living with HIV (PLH) experience higher rates of HPV infection as well as an increased risk of HPV-related disease, including malignancies. Although they are considered a high-priority group for HPV vaccination, there are limited data regarding the long-term immunogenicity and efficacy of HPV vaccines in this population. Seroconversion rates and geometric mean titers elicited by vaccination are lower in PLH compared to immunocompetent participants, especially in individuals with CD4 counts below 200 cells/mm3 and a detectable viral load. The significance of these differences is still unclear, as a correlate of protection has not been identified. Few studies have focused on demonstrating vaccine efficacy in PLH, with variable results depending on the age at vaccination and baseline seropositivity. Although waning humoral immunity for HPV seems to be more rapid in this population, there is evidence that suggests that seropositivity lasts at least 2-4 years following vaccination. Further research is needed to determine the differences between vaccine formulations and the impact of administrating additional doses on durability of immune protection.

5.
J Clin Invest ; 133(10)2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36951954

RESUMEN

BackgroundMaintaining durable immunity following vaccination represents a major challenge, but whether mRNA booster vaccination improves durability is unknown.MethodsWe measured antibody responses in 55 healthy adults, who received a booster dose of the Pfizer-BioNTech or Moderna vaccine against SARS-CoV-2 and calculated the half-life of the antibody titers. We also measured memory B and T cell responses in a subset of 28 participants. In 13 volunteers who received a second booster vaccine, we measured serum antibody titers and memory B and T cell responses.ResultsThe booster (third immunization) dose at 6 to 10 months increased the half-life of the serum-neutralizing antibody (nAb) titers to 76 days from 56 to 66 days after the primary 2-dose vaccination. A second booster dose (fourth immunization) a year after the primary vaccination further increased the half-life to 88 days. However, despite this modestly improved durability in nAb responses against the ancestral (WA.1) strain, there was a loss of neutralization capacity against the Omicron subvariants BA.2.75.2, BQ.1.1, and XBB.1.5 (48-, 71-, and 66-fold drop in titers, respectively, relative to the WA.1 strain). Although only 45% to 65% of participants demonstrated a detectable nAb titer against the newer variants after the booster (third dose), the response declined to below the detection limit in almost all individuals by 6 months. In contrast, booster vaccination induced antigen-specific memory B and T cells that persisted for at least 6 months.ConclusionThe durability of serum antibody responses improves only marginally following booster immunizations with the Pfizer-BioNTech or Moderna mRNA vaccines.


Asunto(s)
COVID-19 , Adulto , Humanos , COVID-19/prevención & control , SARS-CoV-2 , Vacunas contra la COVID-19 , Vacunación , ARN Mensajero , Inmunidad , Anticuerpos Antivirales , Anticuerpos Neutralizantes
6.
Nat Med ; 29(9): 2334-2346, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37640860

RESUMEN

Vaccine protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection wanes over time, requiring updated boosters. In a phase 2, open-label, randomized clinical trial with sequentially enrolled stages at 22 US sites, we assessed safety and immunogenicity of a second boost with monovalent or bivalent variant vaccines from mRNA and protein-based platforms targeting wild-type, Beta, Delta and Omicron BA.1 spike antigens. The primary outcome was pseudovirus neutralization titers at 50% inhibitory dilution (ID50 titers) with 95% confidence intervals against different SARS-CoV-2 strains. The secondary outcome assessed safety by solicited local and systemic adverse events (AEs), unsolicited AEs, serious AEs and AEs of special interest. Boosting with prototype/wild-type vaccines produced numerically lower ID50 titers than any variant-containing vaccine against all variants. Conversely, boosting with a variant vaccine excluding prototype was not associated with decreased neutralization against D614G. Omicron BA.1 or Beta monovalent vaccines were nearly equivalent to Omicron BA.1 + prototype or Beta + prototype bivalent vaccines for neutralization of Beta, Omicron BA.1 and Omicron BA.4/5, although they were lower for contemporaneous Omicron subvariants. Safety was similar across arms and stages and comparable to previous reports. Our study shows that updated vaccines targeting Beta or Omicron BA.1 provide broadly crossprotective neutralizing antibody responses against diverse SARS-CoV-2 variants without sacrificing immunity to the ancestral strain. ClinicalTrials.gov registration: NCT05289037 .


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Vacunas contra la COVID-19/efectos adversos , SARS-CoV-2/genética , COVID-19/prevención & control , Anticuerpos ampliamente neutralizantes
8.
Res Sq ; 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37205592

RESUMEN

Vaccine protection against COVID-19 wanes over time and has been impacted by the emergence of new variants with increasing escape of neutralization. The COVID-19 Variant Immunologic Landscape (COVAIL) randomized clinical trial (clinicaltrials.gov NCT05289037) compares the breadth, magnitude and durability of antibody responses induced by a second COVID-19 vaccine boost with mRNA (Moderna mRNA-1273 and Pfizer-BioNTech BNT162b2), or adjuvanted recombinant protein (Sanofi CoV2 preS DTM-AS03) monovalent or bivalent vaccine candidates targeting ancestral and variant SARS-CoV-2 spike antigens (Beta, Delta and Omicron BA.1). We found that boosting with a variant strain is not associated with loss in neutralization against the ancestral strain. However, while variant vaccines compared to the prototype/wildtype vaccines demonstrated higher neutralizing activity against Omicron BA.1 and BA.4/5 subvariants for up to 3 months after vaccination, neutralizing activity was lower for more recent Omicron subvariants. Our study, incorporating both antigenic distances and serologic landscapes, can provide a framework for objectively guiding decisions for future vaccine updates.

9.
medRxiv ; 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37034641

RESUMEN

In a randomized clinical trial, we compare early neutralizing antibody responses after boosting with bivalent SARS-CoV-2 mRNA vaccines based on either BA.1 or BA.4/BA.5 Omicron spike protein combined with wildtype spike. Responses against SARS-CoV-2 variants exhibited the greatest reduction in titers against currently circulating Omicron subvariants for both bivalent vaccines.

10.
medRxiv ; 2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36482977

RESUMEN

Waning immunity to vaccination represents a major challenge in vaccinology. Whether booster vaccination improves the durability of immune responses is unknown. Here we show, using a cohort of 55 adult vaccinees who received the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine against SARS-CoV-2, that a booster (i.e., 3 rd immunization) dose at 6 - 10 months increased the half-life of serum neutralizing antibody (nAb) titers to 76 days from 56 - 66 days estimated after the primary two-dose vaccination series. A second booster dose (i.e., 4 th immunization) more than a year after the primary vaccination increased the half-life further to 88 days. However, despite this modestly improved durability in nAb responses against the Wuhan strain, there was a loss in neutralization capacity against Omicron subvariants, especially the recently emerged variants, BA.2.75.2 and BQ.1.1 (35 and 50-fold drop in titers respectively, relative to the ancestral (WA.1) strain. While only 55 â€" 65% of participants demonstrated a detectable nAb titer against the newer variants after the booster (3 rd dose), the response declined to below the detection limit in almost all individuals by 6 months. Notably, even against BA.1 and BA.5, the titers declined rapidly in a third of the vaccinees and were below the detection limit at 6 months. In contrast, booster vaccination induced antigen-specific memory B and T cells that persisted for at least 6 months. Collectively, our data show that the durability of immune responses improves following subsequent booster immunizations; however, the emergence of immune evasive variants reduces the effectiveness of booster doses in preventing infection.

11.
medRxiv ; 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35898343

RESUMEN

Background: Protection from SARS-CoV-2 vaccines wanes over time and is compounded by emerging variants including Omicron subvariants. This study evaluated safety and immunogenicity of SARS-CoV-2 variant vaccines. Methods: This phase 2 open-label, randomized trial enrolled healthy adults previously vaccinated with a SARS-CoV-2 primary series and a single boost. Eligible participants were randomized to one of six Moderna COVID19 mRNA vaccine arms (50µg dose): Prototype (mRNA-1273), Omicron BA.1+Beta (1 or 2 doses), Omicron BA.1+Delta, Omicron BA.1 monovalent, and Omicron BA.1+Prototype. Neutralization antibody titers (ID 50 ) were assessed for D614G, Delta, Beta and Omicron BA.1 variants and Omicron BA.2.12.1 and BA.4/BA.5 subvariants 15 days after vaccination. Results: From March 30 to May 6, 2022, 597 participants were randomized and vaccinated. Median age was 53 years, and 20% had a prior SARS-CoV-2 infection. All vaccines were safe and well-tolerated. Day 15 geometric mean titers (GMT) against D614G were similar across arms and ages, and higher with prior infection. For uninfected participants, Day 15 Omicron BA.1 GMTs were similar across Omicron-containing vaccine arms (3724-4561) and higher than Prototype (1,997 [95%CI:1,482-2,692]). The Omicron BA.1 monovalent and Omicron BA.1+Prototype vaccines induced a geometric mean ratio (GMR) to Prototype for Omicron BA.1 of 2.03 (97.5%CI:1.37-3.00) and 1.56 (97.5%CI:1.06-2.31), respectively. A subset of samples from uninfected participants in four arms were also tested in a different laboratory at Day 15 for neutralizing antibody titers to D614G and Omicron subvariants BA.1, BA.2.12.2 and BA.4/BA.5. Omicron BA.4/BA.5 GMTs were approximately one third BA.1 GMTs (Prototype 517 [95%CI:324-826] vs. 1503 [95%CI:949-2381]; Omicron BA.1+Beta 628 [95%CI:367-1,074] vs. 2125 [95%CI:1139-3965]; Omicron BA.1+Delta 765 [95%CI:443-1,322] vs. 2242 [95%CI:1218-4128] and Omicron BA.1+Prototype 635 [95%CI:447-903] vs. 1972 [95%CI:1337-2907). Conclusions: Higher Omicron BA.1 titers were observed with Omicron-containing vaccines compared to Prototype vaccine and titers against Omicron BA.4/BA.5 were lower than against BA.1 for all candidate vaccines. Clinicaltrialsgov: NCT05289037.

12.
Foot Ankle Int ; 40(1_suppl): 8S-9S, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31322947

RESUMEN

RECOMMENDATION: The administration of prophylactic antibiotics before total ankle arthroplasty (TAA) potentially reduces the incidence of surgical site infection (SSI) and/or periprosthetic joint infection (PJI). Weight-based (of at least 2 g) cefazolin administered intravenously within 60 minutes before the procedure can be an adequate choice for antibiotic prophylaxis. If the patient has a beta-lactam anaphylaxis, we recommend an appropriate alternative antibiotic effective against Staphylococcus. It is unclear whether prophylaxis should be given as a single dose or as multiple doses. LEVEL OF EVIDENCE: Strong. DELEGATE VOTE: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).


Asunto(s)
Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Artroplastia de Reemplazo de Tobillo , Cefazolina/uso terapéutico , Infecciones Relacionadas con Prótesis/prevención & control , Infección de la Herida Quirúrgica/prevención & control , Consenso , Humanos , Infecciones Relacionadas con Prótesis/microbiología , Infección de la Herida Quirúrgica/microbiología
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