Angela Karani
A5020827597- Pneumonia and Respiratory Infections
- SARS-CoV-2 and COVID-19 Research
- Respiratory viral infections research
- SARS-CoV-2 detection and testing
- COVID-19 diagnosis using AI
- COVID-19 epidemiological studies
- Bacterial Infections and Vaccines
- Pneumocystis jirovecii pneumonia detection and treatment
- Vaccine Coverage and Hesitancy
- Viral Infections and Outbreaks Research
- COVID-19 Clinical Research Studies
- Influenza Virus Research Studies
- Biosensors and Analytical Detection
- Viral gastroenteritis research and epidemiology
- Immune responses and vaccinations
- Streptococcal Infections and Treatments
- Emergency and Acute Care Studies
- Amino Acid Enzymes and Metabolism
- Virology and Viral Diseases
- Simulation Techniques and Applications
- Child and Adolescent Health
- Immunodeficiency and Autoimmune Disorders
- Cystic Fibrosis Research Advances
- Scientific Computing and Data Management
- COVID-19 Impact on Reproduction
Kenya Medical Research Institute
2016-2025
Wellcome Trust
2010-2024
University of London
2024
University College London
2024
London School of Hygiene & Tropical Medicine
2024
Background The eff ect of 7-valent pneumococcal conjugate vaccine (PCV) in developed countries was enhanced by indirect protection unvaccinated individuals, mediated reduced nasopharyngeal carriage vaccine-serotype pneumococci.The potential 10-valent PCV (PCV10) a developing country setting is unknown.We sought to estimate the ectiveness introduction PCV10 Kenya against serotypes and its on other bacteria.Methods introduced into infant vaccination programme January, 2011, accompanied...
Ten-valent pneumococcal conjugate vaccine (PCV10), delivered at 6, 10, and 14 weeks of age was introduced in Kenya January, 2011, accompanied by a catch-up campaign Kilifi County for children aged younger than 5 years. Coverage with least two PCV10 doses 2-11 months 80% 2011 84% 2016; coverage one dose 12-59 66% 87% 2016. We aimed to assess effect against nasopharyngeal carriage invasive disease (IPD) adults County.
Background Pneumococcal conjugate vaccines (PCV) reduce nasopharyngeal carriage of vaccine-serotype pneumococci but increase in the non-vaccine serotypes. We studied epidemiology among children 3–59 months old before vaccine introduction Kilifi, Kenya. Methods In a rolling cross-sectional study from October 2006 to December 2008 we approached 3570 healthy selected at random population register Kilifi Health and Demographic Surveillance System 134 HIV-infected registered specialist clinic. A...
Lack of a gold standard for identifying bacterial and viral etiologies pneumonia has limited evaluation C-reactive protein (CRP) pneumonia. We evaluated the sensitivity specificity CRP vs respiratory syncytial virus (RSV) in Pneumonia Etiology Research Child Health (PERCH) multicenter case-control study. measured serum levels cases with World Organization–defined severe or very subset community controls. elevated "confirmed" (positive blood culture positive lung aspirate pleural fluid...
Background. To understand and model the impact of pneumococcal conjugate vaccines at population level, we need to know transmission dynamics individual serotypes. We estimated serotype-specific clearance acquisition rates nasopharyngeal colonization among Kenyan children.
Antibiotic exposure and specimen volume are known to affect pathogen detection by culture. Here we assess their effects on bacterial both culture polymerase chain reaction (PCR) in children. PERCH (Pneumonia Etiology Research for Child Health) is a case-control study of pneumonia children aged 1–59 months investigating pathogens blood, nasopharyngeal/oropharyngeal (NP/OP) swabs, induced sputum PCR. was ascertained serum bioassay, cases, record antibiotic treatment prior collection....
Abstract Background Few studies have assessed the seroprevalence of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers (HCWs) in Africa. We report findings from a survey HCWs 3 counties Kenya. Methods recruited 684 Kilifi (rural), Busia and Nairobi (urban) counties. The serosurvey was conducted between 30 July 4 December 2020. tested for immunoglobulin G to SARS-CoV-2 spike protein, using enzyme-linked immunosorbent assay. Assay...
We sought to estimate SARS-CoV-2 antibody seroprevalence within representative samples of the Kenyan population during third year COVID-19 pandemic and second vaccine use.
Background. Herd protection and serotype replacement disease following introduction of pneumococcal conjugate vaccine (PCV) are attributable to the vaccine's impact on colonization. Prior in Kenya, we did an epidemiological study estimate rate acquisition, by serotype, uncolonized population.
The Pneumonia Etiology Research for Child Health study was conducted across 7 diverse research sites and relied on standardized clinical laboratory methods the accurate meaningful interpretation of pneumonia etiology data. Blood, respiratory specimens, urine were collected from children aged 1-59 months hospitalized with severe or very community controls same age without tested an extensive array diagnostic tests. A testing algorithm standard operating procedures applied all sites. Site...
Introduction The high proportion of SARS-CoV-2 infections that have remained undetected presents a challenge to tracking the progress pandemic and estimating extent population immunity. Methods We used residual blood samples from women attending antenatal care services at three hospitals in Kenya between August 2020 October 2021and validated IgG ELISA for SARS-Cov-2 spike protein adjusted results assay sensitivity specificity. fitted two-component mixture model as an alternative threshold...
Pneumococcal conjugate vaccines are an expensive component of the routine immunization schedule. Fractional-dose regimens may be one option to increase sustainability vaccine program.
Haemophilus influenzae type b (Hib) conjugate vaccine, delivered as a three-dose series without booster, was introduced into the childhood vaccination programme in Kenya 2001. The duration of protection and need for booster dose are unknown. We aimed to assess vaccine effectiveness, impact on nasopharyngeal carriage, population immunity after introduction Hib infancy Kenya. This study took place Kilifi Health Demographic Surveillance System (KHDSS), an area that has been monitored vital...
We investigated the performance of polymerase chain reaction (PCR) on blood in diagnosis pneumococcal pneumonia among children from 7 low- and middle-income countries. tested by PCR for autolysin gene aged 1–59 months Pneumonia Etiology Research Child Health (PERCH) study. Children had World Organization–defined severe or very were age-frequency–matched community controls. Additionally, we general pediatric admissions Kilifi, Kenya, a PERCH site. The proportion PCR-positive was compared...
Abstract Pneumococcal conjugate vaccines (PCVs) protect against invasive pneumococcal disease (IPD) among vaccinees. However, at population level, this protection is driven by indirect effects. PCVs prevent nasopharyngeal acquisition of vaccine-serotype (VT) pneumococci, reducing onward transmission. Each episode preceded infection from a carrier, so vaccine impacts on carriage provide minimum estimate reduction in settings lacking expensive IPD surveillance. We documented prevalence and...
Changes in nasopharyngeal (NP) carriage of vaccine-type (VT) Streptococcus pneumoniae can be used to assess the effectiveness a pneumococcal conjugate vaccine (PCV10). We conducted baseline survey rural (Kumbotso, Kano) and urban (Pakoto, Ogun) Nigeria. In this cross-sectional study, we obtained data on demography, clinical history, risk factors, took NP swabs for culture. calculated crude age-standardised prevalence log-binomial regression factors carriage. Among children aged <5 years, 92%...
Although causing substantial morbidity, the burden of pneumococcal disease among older children and adults in Africa, particularly rural settings, is not well-characterized. We evaluated bacteremia 21,000 persons ≥5 years old a prospective cohort as part population-based infectious surveillance western Kenya from October 2006-September 2008. Blood cultures were done on patients meeting pre-defined criteria - severe acute respiratory illness (SARI), fever, admission for any reason at referral...
Background The impact on carriage and optimal schedule for primary vaccination of older children with 10-valent pneumococcal non-typeable Haemophilus influenzae protein-D conjugate vaccine (PHiD-CV) are unknown. Methods 600 Kenyan aged 12–59 months were vaccinated at days 0, 60 180 in a double-blind randomized controlled trial according to the following sequence: Group A: PHiD-CV, diphtheria/tetanus/acellular pertussis (DTaP); B: DTaP, PHiD-CV; C: hepatitis A (HAV), HAV. Nasopharyngeal...
Most of the studies that have informed public health response to COVID-19 pandemic in Kenya relied on samples are not representative general population. We conducted population-based serosurveys at three Health and Demographic Surveillance Systems (HDSSs) determine cumulative incidence infection with SARS-CoV-2.
Background. International recommendations for the control of coronavirus disease 2019 (COVID-19) pandemic emphasize central role laboratory testing severe acute respiratory syndrome 2 (SARS-CoV-2), etiological agent, at scale. The availability reagents, equipment and qualified staff are important bottlenecks to achieving this. Elsewhere, pooled (i.e. combining multiple samples in same reaction) has been suggested increase capacities period. Methods. We discuss our experience with SARS-CoV-2...
Abstract In October 2020, anti-SARS-CoV-2 IgG seroprevalence among truck drivers and their assistants (TDA) in Kenya was 42.3%, higher than other key populations. TDA transport essential supplies during the COVID-19 pandemic, placing them at increased risk of being infected transmitting SARS-CoV-2 infection over a wide geographical area.
In October 2020, anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
<ns4:p><ns4:bold>Background.</ns4:bold> International recommendations for the control of coronavirus disease 2019 (COVID-19) pandemic emphasize central role laboratory testing severe acute respiratory syndrome 2 (SARS-CoV-2), etiological agent, at scale. The availability reagents, equipment and qualified staff are important bottlenecks to achieving this. Elsewhere, pooled (i.e. combining multiple samples in same reaction) has been suggested increase capacities period.</ns4:p><ns4:p>...