Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
1.
Ann Intern Med ; 174(8): 1073-1080, 2021 08.
Article in English | MEDLINE | ID: covidwho-1456490

ABSTRACT

BACKGROUND: Assessing the evolution of SARS-CoV-2 immune response among patients receiving dialysis can define its durability in a highly clinically relevant context because patients receiving dialysis share the characteristics of persons most susceptible to SARS-CoV-2 infection. OBJECTIVE: To evaluate the persistence of SARS-CoV-2 receptor-binding domain (RBD) IgG in seroprevalent patients receiving dialysis. DESIGN: Prospective. SETTING: Nationwide sample from dialysis facilities. PATIENTS: 2215 patients receiving dialysis who had evidence of SARS-CoV-2 infection as of July 2020. MEASUREMENTS: Remainder plasma from routine monthly laboratories was used to measure semiquantitative RBD IgG index value over 6 months. RESULTS: A total of 2063 (93%) seroprevalent patients reached an assay detectable response (IgG index value ≥1). Most (n = 1323, 60%) had responses in July with index values classified as high (IgG ≥10); 1003 (76%) remained within this stratum. Adjusted median index values declined slowly but continuously (July vs. December values were 21 vs. 13; P < 0.001). The trajectory of the response did not vary by age group, sex, race/ethnicity, or diabetes status. Patients without an assay detectable response (n = 137) were more likely to be White and in the younger (18 to 44 years) or older (≥80 years) age groups and less likely to have diabetes and hypoalbuminemia. LIMITATION: Lack of data on symptoms or reverse transcriptase polymerase chain reaction diagnosis, cohort of persons who survived infection, and use of a semiquantitative assay. CONCLUSION: Despite impaired immunity, most seropositive patients receiving dialysis maintained RBD antibody levels over 6 months. A slow and continual decline in median antibody levels over time was seen, but no indication that subgroups with impaired immunity had a shorter-lived humoral response was found. PRIMARY FUNDING SOURCE: Ascend Clinical Laboratories.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Immunoglobulin G/blood , Protein Domains/immunology , Renal Dialysis , Spike Glycoprotein, Coronavirus/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , SARS-CoV-2 , Young Adult
2.
Iran J Immunol ; 18(1): 1-12, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-1160970

ABSTRACT

Severe Acute Respiratory Syndrome (SARS) associated with SARS-CoV-2, causes a severe form of the respiratory illness known as Coronavirus Disease-19 (COVID-19). COVID-19 has emerged as a worldwide pandemic with a high number of fatalities. Approximately 112,654,202 people have been infected so far with this disease which has led to the death of more than one point seven million (2,496,749) till 24th Feb, 2021. Measures to counter this disease have led to a global economic slowdown. Multiple drug trials are ongoing and several putative candidates for vaccination against the virus have been approved and are in the pipeline. Many studies have also characterized the immunological profile of patients infected with COVID-19. Some studies suggest that the severity of the COVID-19 infection is directly associated with the cytokine storm. In this review, we aim to compile the available knowledge and describe the nature of immune responses in patients infected with COVID-19 in different age groups, comorbidity, and immune-compromised state and their association with disease severity.


Subject(s)
Adaptive Immunity , COVID-19/immunology , Immunity, Innate , SARS-CoV-2/immunology , Adaptive Immunity/drug effects , Age Factors , Antiviral Agents/therapeutic use , COVID-19/drug therapy , COVID-19/mortality , COVID-19/therapy , COVID-19/virology , COVID-19 Vaccines/therapeutic use , Comorbidity , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/virology , Host-Pathogen Interactions , Humans , Immunity, Humoral , Immunity, Innate/drug effects , Immunocompromised Host , Prognosis , Risk Assessment , Risk Factors , Severity of Illness Index
3.
BMC Med ; 19(1): 35, 2021 02 03.
Article in English | MEDLINE | ID: covidwho-1061076

ABSTRACT

BACKGROUND: The COVID-19 pandemic has disrupted routine measles immunisation and supplementary immunisation activities (SIAs) in most countries including Kenya. We assessed the risk of measles outbreaks during the pandemic in Kenya as a case study for the African Region. METHODS: Combining measles serological data, local contact patterns, and vaccination coverage into a cohort model, we predicted the age-adjusted population immunity in Kenya and estimated the probability of outbreaks when contact-reducing COVID-19 interventions are lifted. We considered various scenarios for reduced measles vaccination coverage from April 2020. RESULTS: In February 2020, when a scheduled SIA was postponed, population immunity was close to the herd immunity threshold and the probability of a large outbreak was 34% (8-54). As the COVID-19 contact restrictions are nearly fully eased, from December 2020, the probability of a large measles outbreak will increase to 38% (19-54), 46% (30-59), and 54% (43-64) assuming a 15%, 50%, and 100% reduction in measles vaccination coverage. By December 2021, this risk increases further to 43% (25-56), 54% (43-63), and 67% (59-72) for the same coverage scenarios respectively. However, the increased risk of a measles outbreak following the lifting of all restrictions can be overcome by conducting a SIA with ≥ 95% coverage in under-fives. CONCLUSION: While contact restrictions sufficient for SAR-CoV-2 control temporarily reduce measles transmissibility and the risk of an outbreak from a measles immunity gap, this risk rises rapidly once these restrictions are lifted. Implementing delayed SIAs will be critical for prevention of measles outbreaks given the roll-back of contact restrictions in Kenya.


Subject(s)
COVID-19/epidemiology , Disease Outbreaks/prevention & control , Measles Vaccine/supply & distribution , Measles/prevention & control , SARS-CoV-2 , Adolescent , COVID-19/complications , Child , Child, Preschool , Female , Humans , Immunization Programs , Infant , Infant, Newborn , Kenya/epidemiology , Male , Measles/blood , Measles/complications , Vaccination Coverage
4.
Pathogens ; 9(10)2020 Oct 06.
Article in English | MEDLINE | ID: covidwho-905981

ABSTRACT

The coronavirus disease 19 (COVID-19) is caused by the highly transmissible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has affected the global population despite socioeconomic status and amazed surveillance agencies for its incidence, mortality, and recovery rates. COVID-19 affects all age groups; however, it is suggested to progress into severe disease and cause mortality in over 10% of the confirmed cases, depending on the individual characteristics of the affected population. One of the biggest unanswered questions it is why only some individuals develop into the severe stages of the disease. Current data indicate that most of the critically ill are the elderly or those with comorbidities such as hypertension, diabetes, and asthma. However, it has been noted that, in some populations, severe disease is mostly observed in much younger individuals (<60-years old) with no reported underlying medical conditions. Certainly, many factors may contribute to disease severity including intrinsic host factors such as genetic variants, the expression levels of tissue proteins, among others. Considering all these aspects, this review aims to discuss how the expression levels of tissue proteases and the different profiles of immune responses influence the susceptibility to COVID-19 as well as disease severity and outcome.

SELECTION OF CITATIONS
SEARCH DETAIL