The impact of the COVID-19 pandemic on vaccine coverage in Kilifi, Kenya: A retrospective cohort study.

The COVID-19 pandemic caused unprecedented disruption in health service delivery, globally. This study sought to provide evidence on the impact of the pandemic on vaccine coverage in Kilifi County, Kenya. We conducted a vaccine coverage survey between April and June 2021 within the Kilifi Health and Demographic Surveillance System (KHDSS). Simple random sampling was used to identify 1500 children aged 6 weeks-59 months. Participants were grouped into three retrospective cohorts based on when they became age-eligible for vaccination: before the pandemic, during the first year, or during the second year of the pandemic. Survival analysis with Cox regression was used to evaluate the association between the time-period at which participants became age-eligible for vaccination and the rate of vaccination within a month of age-eligibility for the third dose of pentavalent vaccine (Pentavalent-3) and within three months of age-eligibility for the first dose of Measles vaccine (MCV-1). A total of 1,341 participants were included in the survey. Compared to the pre-COVID-19 baseline period, the rate of vaccination within a month of age-eligibility for Pentavalent-3 was not significantly different in the first year of the pandemic (adjusted hazard ratio [aHR] 1.03, 95 % confidence interval [CI] 0.90-1.18) and was significantly higher during the second year of the pandemic (aHR 1.33, 95 % CI 1.07-1.65). The rate of vaccination with MCV-1 within three months of age-eligibility was not significantly different among those age-eligible for vaccination during the first year of the pandemic (aHR 1.04, 95 % CI 0.88-1.21) and was 35 % higher during the second year of the pandemic (95 % CI 1.11-1.64), compared to those age-eligible pre-COVID-19. After adjusting for known determinants of vaccination, the COVID-19 pandemic did not adversely affect the rate of vaccination within the KHDSS.

The importance of supplementary immunisation activities to prevent measles outbreaks during the COVID-19 pandemic in Kenya.

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.

Expression and Prognostic Relevance of GAGE1 and XAGE1 Cancer/Testis Antigens in Head and Neck Squamous Cell Carcinoma.

BACKGROUND: In the last decades, survival rates in head and neck squamous cell carcinoma (HNSCC) have not changed, with a five-year survival of only 50%. Thus, there is a great need for the identification of new molecular targets and development of novel therapeutic strategies. Cancer-testis antigens (CTAs) are expressed in various types of tumor but rarely in healthy normal tissues. Therefore, they appear as ideal targets for immunotherapy approaches, as well as, unique markers for cancer diagnosis/prognosis. OBJECTIVE: This study evaluated the expression pattern of cancer/testis antigens (CTA) in HNSCC samples and correlated the expression data with the clinicopathological prognostic variables. METHODS: An in silico screening was performed using all CTA genes cataloged on the CTDatabase and the expression of the eight CTA genes (ARMC3, DDX53, FTHL17, GAGE1, MAGEA11, SYCE1, TCP11, and XAGE1) was examined in 89 HNSCC and 20 normal mucosa samples using RT-PCR analysis. RESULTS: GAGE1 (48.3%), XAGE1 (40.4%) and MAGEA11 (19.1%) were frequently and specifically expressed in HNSCC samples and 68.5% of the cases expressed at least one of these antigens. Moreover, GAGE1 and XAGE1 mRNA positivity was significantly associated with the presence of metastasis in the lymph nodes (p=0.038 and p=0.023, respectively) and, by multivariate analysis, male gender (p=0.032), advanced clinical stage (p=0.018) and mRNA positivity for GAGE1 (p=0.010) were independent prognostic factors for overall survival. CONCLUSION: These findings suggest GAGE1 and XAGE1 expressions to be useful as prognostic markers for HNSCC.