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BMC Infectious Diseases May 2023Numerous vaccination research experiments have been conducted on non-primate hosts to prevent or control HTLV-1 infection. Therefore, reviewing recent advancements for...
BACKGROUND
Numerous vaccination research experiments have been conducted on non-primate hosts to prevent or control HTLV-1 infection. Therefore, reviewing recent advancements for status assessment and strategic planning of future preventative actions to reduce HTLV-1 infection and its consequences would be essential.
METHODS
MEDLINE, Scopus, Web of Science, and Clinicaltrials.gov were searched from each database's inception through March 27, 2022. All original articles focusing on developing an HTLV-1 vaccine candidate were included.
RESULTS
A total of 47 studies were included. They used a variety of approaches to develop the HTLV-1 vaccine, including DNA-based, dendritic-cell-based, peptide/protein-based, and recombinant vaccinia virus approaches. The majority of the research that was included utilized Tax, Glycoprotein (GP), GAG, POL, REX, and HBZ as their main peptides in order to develop the vaccine. The immunization used in dendritic cell-based investigations, which were more recently published, was accomplished by an activated CD-8 T-cell response. Although there hasn't been much attention lately on this form of the vaccine, the initial attempts to develop an HTLV-1 immunization depended on recombinant vaccinia virus, and the majority of results seem positive and effective for this type of vaccine. Few studies were conducted on humans. Most of the studies were experimental studies using animal models. Adenovirus, Cytomegalovirus (CMV), vaccinia, baculovirus, hepatitis B, measles, and pox were the most commonly used vectors.
CONCLUSIONS
This systematic review reported recent progression in the development of HTLV-1 vaccines to identify candidates with the most promising preventive and therapeutic effects.
Topics: Animals; Humans; Human T-lymphotropic virus 1; HTLV-I Infections; T-Lymphocytes; Vaccinia virus; Viral Vaccines; Peptides
PubMed: 37170214
DOI: 10.1186/s12879-023-08289-7 -
Frontiers in Pharmacology 2021Viruses cause various human diseases, some of which become pandemic outbreaks. This study synthesized evidence on antiviral medicinal plants in Africa which could... (Review)
Review
Viruses cause various human diseases, some of which become pandemic outbreaks. This study synthesized evidence on antiviral medicinal plants in Africa which could potentially be further studied for viral infections including Coronavirus disease 2019 (COVID-19) treatment. PUBMED, CINAHIL, Scopus, Google Scholar, and Google databases were searched through keywords; antiviral, plant, herb, and Africa were combined using "AND" and "OR". studies, studies, or clinical trials on botanical medicine used for the treatment of viruses in Africa were included. Thirty-six studies were included in the evidence synthesis. Three hundred and twenty-eight plants were screened for antiviral activities of which 127 showed noteworthy activities against 25 viral species. These, were Poliovirus (42 plants), HSV (34 plants), Coxsackievirus (16 plants), Rhinovirus (14plants), Influenza (12 plants), Astrovirus (11 plants), SARS-CoV-2 (10 plants), HIV (10 plants), Echovirus (8 plants), Parvovirus (6 plants), Semiliki forest virus (5 plants), Measles virus (5 plants), Hepatitis virus (3 plants), Canine distemper virus (3 plants), Zika virus (2 plants), Vesicular stomatitis virus T2 (2 plants). Feline herpesvirus (FHV-1), Enterovirus, Dengue virus, Ebola virus, Chikungunya virus, Yellow fever virus, Respiratory syncytial virus, Rift Valley fever virus, Human cytomegalovirus each showed sensitivities to one plant. The current study provided a list of African medicinal plants which demonstrated antiviral activities and could potentially be candidates for COVID-19 treatment. However, all studies were preliminary and screening. Further are required for plant-based management of viral diseases.
PubMed: 35002686
DOI: 10.3389/fphar.2021.682794 -
American Journal of Epidemiology Dec 2019Children infected with human immunodeficiency virus (HIV) are at increased risk of measles morbidity and mortality. We searched abstracts from the PubMed, Embase, and...
Children infected with human immunodeficiency virus (HIV) are at increased risk of measles morbidity and mortality. We searched abstracts from the PubMed, Embase, and Latin American and Caribbean Center on Health Sciences Information databases for articles published from the earliest date available through September 26, 2017. The primary outcome of interest was serological responses to measles vaccine, stratified by HIV infection status. A total of 2,858 potentially eligible articles were identified, and the final review included 12 studies published between 1992 and 2013, 9 of which reported data on vaccine safety. The studies we included represented 3,573 children, of whom at least 335 were infected with HIV, 788 were HIV-exposed but not infected, and 1,478 were unexposed to HIV. Four of the 12 studies found statistically significant reductions in seropositivity among HIV-infected children compared with HIV-uninfected children within 4 months of vaccination (prevalence ratio range, 0.44-0.70), and forest plots provided visual trends of decreasing immunity over time among HIV-infected children in 2 additional studies. No vaccine-related deaths or serious adverse events were reported. This updated review demonstrated limitations of the existing published literature but supported evidence of reduced immunogenicity of measles vaccine among HIV-infected children, supporting the World Health Organization recommendation to revaccinate HIV-infected children against measles following immune reconstitution with combination antiretroviral therapy.
Topics: Child; HIV Infections; Humans; Immunogenicity, Vaccine; Measles; Measles Vaccine
PubMed: 31210268
DOI: 10.1093/aje/kwz144 -
The Lancet. Infectious Diseases Nov 2019Vaccinating infants with a first dose of measles-containing vaccine (MCV1) before 9 months of age in high-risk settings has the potential to reduce measles-related... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Vaccinating infants with a first dose of measles-containing vaccine (MCV1) before 9 months of age in high-risk settings has the potential to reduce measles-related morbidity and mortality. However, there is concern that early vaccination might blunt the immune response to subsequent measles vaccine doses. We systematically reviewed the available evidence on the effect of MCV1 administration to infants younger than 9 months on their immune responses to subsequent MCV doses.
METHODS
For this systematic review and meta-analysis, we searched for randomised and quasi-randomised controlled trials, outbreak investigations, and cohort and case-control studies without restriction on publication dates, in which MCV1 was administered to infants younger than 9 months. We did the literature search on June 2, 2015, and updated it on Jan 14, 2019. We included studies reporting data on strength or duration of humoral and cellular immune responses, and on vaccine efficacy or vaccine effectiveness after two-dose or three-dose MCV schedules. Our outcome measures were proportion of seropositive infants, geometric mean titre, vaccine efficacy, vaccine effectiveness, antibody avidity index, and T-cell stimulation index. We used random-effects meta-analysis to derive pooled estimates of the outcomes, where appropriate. We assessed the methodological quality of included studies using Grading of Recommendation Assessment, Development and Evaluation (GRADE) guidelines.
FINDINGS
Our search retrieved 1156 records and 85 were excluded due to duplication. 1071 records were screened for eligibility, of which 351 were eligible for full-text screening and 21 were eligible for inclusion in the review. From 13 studies, the pooled proportion of infants seropositive after two MCV doses, with MCV1 administered before 9 months of age, was 98% (95% CI 96-99; I=79·8%, p<0·0001), which was not significantly different from seropositivity after a two-dose MCV schedule starting later (p=0·087). Only one of four studies found geometric mean titres after MCV2 administration to be significantly lower when MCV1 was administered before 9 months of age than at 9 months of age or later. There was insufficient evidence to determine an effect of age at MCV1 administration on antibody avidity. The pooled vaccine effectiveness estimate derived from two studies of a two-dose MCV schedule with MCV1 vaccination before 9 months of age was 95% (95% CI 89-100; I=12·6%, p=0·29). Seven studies reporting on measles virus-specific cellular immune responses found that T-cell responses and T-cell memory were sustained, irrespective of the age of MCV1 administration. Overall, the quality of evidence was moderate to very low.
INTERPRETATION
Our findings suggest that administering MCV1 to infants younger than 9 months followed by additional MCV doses results in high seropositivity, vaccine effectiveness, and T-cell responses, which are independent of the age at MCV1, supporting the vaccination of very young infants in high-risk settings. However, we also found some evidence that MCV1 administered to infants younger than 9 months resulted in lower antibody titres after one or two subsequent doses of MCV than when measles vaccination is started at age 9 months or older. The clinical and public-health relevance of this immunity blunting effect are uncertain.
FUNDING
WHO.
Topics: Age Factors; Antibodies, Viral; Female; Humans; Immunity, Cellular; Immunity, Humoral; Immunization Schedule; Infant; Male; Measles; Measles Vaccine; Measles virus; T-Lymphocytes; Treatment Outcome
PubMed: 31548081
DOI: 10.1016/S1473-3099(19)30396-2 -
BMC Infectious Diseases May 2018Information on the incubation period and period of infectiousness or shedding of infectious pathogens is critical for management and control of communicable diseases in...
BACKGROUND
Information on the incubation period and period of infectiousness or shedding of infectious pathogens is critical for management and control of communicable diseases in schools and other childcare settings.
METHODS
We performed a systematic literature review (Pubmed and Embase) to identify and critically appraise all relevant published articles using incubation, infectiousness or shedding, and exclusion period as parameters for the search. No language, time, geographical or study design restrictions were applied.
RESULTS
A total of 112 articles met the eligibility criteria. A relatively large number were retrieved for gastrointestinal diseases and influenza or respiratory syncytial virus, but there were few or no studies for other diseases. Although a considerable number of publications reported the incubation and shedding periods, there was less evidence concerning the period of infectiousness. On average, five days of exclusion is considered for measles, mumps, rubella, varicella and pertussis. For other diseases, such as most cases of meningococcal disease, hepatitis A and influenza exclusion is considered as long as severe symptoms persist. However, these results are based on a diverse range of study characteristics, including age, treatment, vaccination, underlying diseases, diagnostic tools, viral load, study design and definitions, making statistical analysis difficult.
CONCLUSIONS
Despite inconsistent definitions for key variables and the diversity of studies reviewed, published data provide sufficient quantitative estimates to inform decision making in schools and other childcare settings. The results can be used as a reference when deciding about the exclusion of a child with a communicable disease that both prevents exposure and avoids unnecessary absenteeism.
Topics: Adolescent; Chickenpox; Child; Child Care; Child, Preschool; Communicable Disease Control; Communicable Diseases; Hepatitis A; Humans; Infant; Infectious Disease Incubation Period; Influenza, Human; Measles; Mumps; Rubella; Schools; Vaccination; Whooping Cough
PubMed: 29716545
DOI: 10.1186/s12879-018-3095-8 -
European Journal of Public Health Apr 2024Child vaccinations are among the most effective public health interventions. However, wide gaps in child vaccination remain among different groups with uptake in most...
Understanding the health system barriers and enablers to childhood MMR and HPV vaccination among disadvantaged, minority or underserved populations in middle- and high-income countries: a systematic review.
BACKGROUND
Child vaccinations are among the most effective public health interventions. However, wide gaps in child vaccination remain among different groups with uptake in most minorities or ethnic communities in Europe substantially lower compared to the general population. A systematic review was conducted to understand health system barriers and enablers to measles, mumps and rubella (MMR) and human papilloma virus (HPV) child vaccination among disadvantaged, minority populations in middle- and high-income countries.
METHODS
We searched Medline, Cochrane, CINAHL, ProQuest and EMBASE for articles published from 2010 to 2021. Following title and abstract screening, full texts were assessed for relevance. Study quality was appraised using Critical Appraisal Skills Program checklists. Data extraction and analysis were performed. Health system barriers and enablers to vaccination were mapped to the World Health Organization health system building blocks.
RESULTS
A total of 1658 search results were identified from five databases and 24 from reference lists. After removing duplicates, 1556 titles were screened and 496 were eligible. Eighty-six full texts were assessed for eligibility, 28 articles met all inclusion criteria. Factors that affected MMR and HPV vaccination among disadvantaged populations included service delivery (limited time, geographic distance, lack of culturally appropriate translated materials, difficulties navigating healthcare system), healthcare workforce (language and poor communication skills), financial costs and feelings of discrimination.
CONCLUSION
Policymakers must consider health system barriers to vaccination faced by disadvantaged, minority populations while recognizing specific cultural contexts of each population. To ensure maximum policy impact, approaches to encourage vaccinations should be tailored to the unique population's needs. A one-size-fits-all approach is not effective.
Topics: Child; Humans; Vulnerable Populations; Developed Countries; Papillomavirus Infections; Vaccination; Delivery of Health Care
PubMed: 38183166
DOI: 10.1093/eurpub/ckad232 -
The Cochrane Database of Systematic... Aug 2016Reduced vitamin A concentration increases the risk of blindness in children infected with the measles virus. Promoting vitamin A supplementation in children with measles... (Review)
Review
BACKGROUND
Reduced vitamin A concentration increases the risk of blindness in children infected with the measles virus. Promoting vitamin A supplementation in children with measles contributes to the control of blindness in children, which is a high priority within the World Health Organization (WHO) VISION 2020 The Right to Sight Program.
OBJECTIVES
To assess the efficacy of vitamin A in preventing blindness in children with measles without prior clinical features of vitamin A deficiency.
SEARCH METHODS
We searched CENTRAL 2015, Issue 11, MEDLINE (1950 to December week 3, 2015), Embase (1974 to December 2015) and LILACS (1985 to December 2015).
SELECTION CRITERIA
Randomised controlled trials (RCTs) assessing the efficacy of vitamin A in preventing blindness in well-nourished children diagnosed with measles but with no prior clinical features of vitamin A deficiency.
DATA COLLECTION AND ANALYSIS
For the original review, two review authors independently assessed studies for eligibility and extracted data on reported outcomes. We contacted trial authors of the included studies for additional information on unpublished data. We included two RCTs which were clinically heterogenous. We presented the continuous outcomes reported as the mean difference (MD) with 95% confidence interval (CI) and dichotomous outcomes as risk ratio (RR) with 95% CI. Due to marked clinical heterogeneity we considered it inappropriate to perform a meta-analysis.
MAIN RESULTS
For the first publication of this review, two RCTs involving 260 children with measles which compared vitamin A with placebo met the inclusion criteria. Neither study reported blindness or other ocular morbidities as end points. One trial of moderate quality suggested evidence of a significant increase in serum retinol levels in the vitamin A group one week after two doses of vitamin A (MD 9.45 µg/dL, 95% CI 2.19 to 16.71; 17 participants, moderate-quality evidence), but not six weeks after three doses of vitamin A (MD 2.56 µg/dL, 95% CI -5.28 to 10.40; 39 participants, moderate-quality evidence). There was no significant difference in weight gain six weeks (MD 0.39 kg, -0.04 to 0.82; 48 participants, moderate-quality evidence) and six months (MD 0.52 kg, 95% CI -0.08 to 1.12; 36 participants, moderate-quality evidence) after three doses of vitamin A.The second trial found no significant difference in serum retinol levels two weeks after a single dose of vitamin A (MD 2.67 µg/dL, 95% CI -0.29 to 5.63; 155 participants, moderate-quality evidence). Percentage of undernutrition between the two groups did not differ significantly at one week (RR 0.93, 95% CI 0.56 to 1.54, 145 participants) and two weeks (RR 0.82, 95% CI 0.52 to 1.29, 147 participants) after a single dose of vitamin A. No adverse event was reported in either study. We did not find any new RCTS for this second update.
AUTHORS' CONCLUSIONS
We did not find any trials assessing whether or not vitamin A supplementation in children with measles prevents blindness, as neither study reported blindness or other ocular morbidities as end points.
Topics: Adolescent; Blindness; Child; Child, Preschool; Humans; Infant; Measles; Randomized Controlled Trials as Topic; Vitamin A; Vitamins
PubMed: 27580345
DOI: 10.1002/14651858.CD007719.pub4 -
Current Journal of Neurology Jul 2021The environmental factors play a major role as risk factors of multiple sclerosis (MS). This study aimed at gathering environmental risk factors of MS in the Middle... (Review)
Review
The environmental factors play a major role as risk factors of multiple sclerosis (MS). This study aimed at gathering environmental risk factors of MS in the Middle East and North Africa (MENA). We used MEDLINE and EMBASE databases by a systematic review method. Out of a total of 123 studies, 16 studies met the eligibility criteria. Totally, 47 risk factors were assessed as follows: six studies found sunlight exposure as a protective factor with the odds ratio (OR) ranging from 0.06 to 0.57. Six studies evaluated smoking as a risk factor with the OR ranging from 1.69 in all patients to 6.48 in female patients. Four studies supported measles infection as a risk factor with the OR ranging from 1.60 to 3.77, and in 3 studies, stressful events had a significant association with the OR of 1.80, 1.90, and 32.57. Among 47 assessed risk factors, sunlight exposure, cigarette smoking, measles infection, Epstein-Barr virus (EBV) infection, and stressful events had a significant association with MS.
PubMed: 38011462
DOI: 10.18502/cjn.v20i3.7693 -
Nutrients Oct 2022Vitamin A (VA) deficiency is associated with increased host susceptibility to infections, but evidence on its role in the prevention and management of viral infections... (Review)
Review
Vitamin A (VA) deficiency is associated with increased host susceptibility to infections, but evidence on its role in the prevention and management of viral infections is still lacking. This review aimed at summarizing the effects of VA supplementation against viral infections to support clinicians in evaluating supplemental treatments. PubMed, Scopus, and Web of Science were searched. Randomized clinical trials comparing the direct effects of VA oral supplementation in any form vs. placebo or standard of care in the prevention and/or management of confirmed viral infections in people of any age were included. A narrative synthesis of the results was performed. The revised Cochrane Risk-Of-Bias tool was used to assess quality. Overall, 40 articles of heterogeneous quality were included. We found data on infections sustained by ( = 17), ( = 2), ( = 1), ( = 3), ( = 4), and ( = 13). Studies were published between 1987 and 2017 and mostly conducted in Africa. The findings were heterogeneous across and within viral families regarding virological, immunological, and biological response, and no meaningful results were found in the prevention of viral infections. For a few diseases, VA-supplemented individuals had a better prognosis and improved outcomes, including clearance of HPV lesions or reduction in some measles-related complications. The effects of VA oral supplementation seem encouraging in relation to the management of a few viral infections. Difference in populations considered, variety in recruitment and treatment protocols might explain the heterogeneity of the results. Further investigations are needed to better identify the benefits of VA administration.
Topics: Dietary Supplements; Humans; Randomized Controlled Trials as Topic; Virus Diseases; Vitamin A; Vitamin D
PubMed: 36235733
DOI: 10.3390/nu14194081 -
Frontiers in Pediatrics 2022In 2011, the first European League Against Rheumatism (EULAR) vaccination recommendations for pediatric patients with autoimmune inflammatory rheumatic diseases...
Efficacy, Immunogenicity and Safety of Vaccination in Pediatric Patients With Autoimmune Inflammatory Rheumatic Diseases (pedAIIRD): A Systematic Literature Review for the 2021 Update of the EULAR/PRES Recommendations.
BACKGROUND
In 2011, the first European League Against Rheumatism (EULAR) vaccination recommendations for pediatric patients with autoimmune inflammatory rheumatic diseases (pedAIIRD) were published. The past decade numerous new studies were performed to assess the safety, efficacy and immunogenicity of vaccinations in pedAIIRD. A systematic literature review (SLR) was therefore performed to serve as the basis for the updated 2021 EULAR/PRES recommendations.
METHODS
An SLR was performed according to the standard operating procedures for EULAR-endorsed recommendations. Primary outcomes were efficacy, immunogenicity and safety of vaccination in pedAIIRD. The search was performed in Medline, Embase and the Cochrane Library and included studies published from November 2010 until July 2020.
RESULTS
The SLR yielded 57 studies which were included for critical appraisal and data extraction. Only 8 studies described the occurrence of vaccine-preventable infections after vaccination (efficacy), none of these studies were powered to assess efficacy. The majority of studies assessed (humoral) immune responses as surrogate endpoint for vaccine efficacy. Studies on non-live vaccines showed that these were safe and in general immunogenic. Biologic disease-modifying antirheumatic drugs (bDMARDs) in general did not significantly reduce seroprotection rates, except for B-cell depleting therapies which severely hampered humoral responses. Four new studies on human papilloma virus vaccination showed that this vaccine was safe and immunogenic in pedAIIRD. Regarding live-attenuated vaccinations, level 1 evidence of the measles mumps rubella (MMR) booster vaccination became available which showed the safety of this booster for patients treated with methotrexate. In addition, level 3 evidence became available that suggested that the MMR and varicella zoster virus (VZV) vaccination for patients on low dose glucocorticosteroids and bDMARDs might be safe as well.
CONCLUSIONS
The past decade, knowledge on the safety and immunogenicity of (live-attenuated) vaccines in pedAIIRD significantly increased. Data on efficacy (infection prevention) remains scarce. The results from this SLR are the basis for the updated EULAR/PRES vaccination recommendations in pedAIIRD.
PubMed: 35874582
DOI: 10.3389/fped.2022.910026