As 2021 drew to a close, Cuba struggled to contain the highly transmissible omicron variant of SARS-CoV-2, braced for a new wave of infections and kept a close eye on other variants of concern popping up around the world-a common experience to countries everywhere as we head into the second year of the pandemic. In Cuba, however, there is one marked difference making all the difference: by early January, 87% of the population was fully vaccinated using a three-dose schedule of vaccines developed and produced on the island.[1] This massive vaccination campaign is complemented by a rapid booster rollout-also using Cuban vaccines-that began in December 2021 and was ongoing as we finalized this issue. The island nation was able to achieve the third highest COVID-19 vaccination rate in the world[2] after decades of scientific investment, research, discovery and innovation; regulatory oversight and compliance; professional training; and increased production capacity. But a vaccine is only as effective as the health system charged with administering it-in a safe and timely manner, to as many people as possible. Here too, Cuba has decades of experience, including a national pediatric immunization program where 98% of children under 5 are immunized against 13 diseases,[3] an annual polio vaccination campaign (both launched in 1962 and uninterrupted since) and campaigns to contain epidemics such as H1N1. When the first COVID-19 cases were detected on the island in March 2020, Cuba harnessed this vaccine experience, making a hard tack towards developing its own vaccines. Two of the main protagonists in the country's biotechnology development, the Finlay Vaccine Institute (IFV) and the Genetic Engineering and Biotechnology Center (CIGB), both with several groundbreaking preventive and therapeutic vaccines in their portfolios, led the search for a vaccine. Today, Cuba has three vaccines authorized for emergency use-Soberana 02 and Soberana Plus developed by IFV, and Abdala, developed by CIGB. Schedules with these vaccines have demonstrated more than 90% efficacy in clinical trials,[4] and after regulatory approval for emergency use, became the backbone of Cuban COVID-19 vaccination efforts. A fourth vaccine, Mambisa (CIGB), administered nasally, and a fifth, Soberana 01 (IFV) are still in clinical trials. For this installment in MEDICC Review's series spotlighting leading women of Cuban science, we sat down with Dr Verena Muzio, Director of Clinical Research at CIGB. A pioneer of Cuba's biotechnology sector, she is an immunologist with a doctorate in biological sciences. Her professional trajectory began researching the genetically engineered hepatitis B surface antigen that led to the development of Cuba's recombinant hepatitis B vaccine in 1989. The same technological platform used in this vaccine was used to develop CIGB's Abdala vaccine against SARS-CoV-2-part of the reason Cuba was able to secure a vaccine so quickly. A phase 3 clinical trial determined a 92.28% efficacy rate for Abdala, with results to appear in forthcoming publications.
INTRODUCTIONFerritin is the best biomarker for assessing iron deficiency, but ferritin concentrations increase with inflammation. Several adjustment methods have been proposed to account for inflammation's effect on iron biomarker interpretation. The most recent and highly recommended method uses linear regression models, but more research is needed on other models that may better define iron status in children, particularly when distributions are heterogenous and in contexts where the effect of inflammation on ferritin is not linear.OBJECTIVEAssess the utility and relevance of quadratic regression models and quantile quadratic regression models in adjusting ferritin concentration in the presence of inflammation.METHODSWe used data from children aged under five years, taken from Cuba's national anemia and iron deficiency survey, which was carried out from 2015-2018 by the National Hygiene, Epidemiology and Microbiology Institute. We included data from 1375 children aged 6 to 59 months and collected ferritin concentrations and two biomarkers for inflammation: C-reactive protein and α-1 acid glycoprotein. Quadratic regression and quantile regression models were used to adjust for changes in ferritin concentration in the presence of inflammation.RESULTSUnadjusted iron deficiency prevalence was 23% (316/1375). Inflammation-adjusted ferritin values increased iron-deficiency prevalence by 2.6-4.5 percentage points when quadratic regression correction model was used, and by 2.8-6.2 when quantile regression was used. The increase when using the quantile regression correction model was more pronounced and statistically significant when both inflammation biomarkers were considered, but adjusted prevalence was similar between the two correction methods when only one biomarker was analyzed.CONCLUSIONSThe use of quadratic regression and quantile quadratic regression models is a complementary strategy in adjusting ferritin for inflammation, and is preferable to standard regression analysis when the linear model's basic assumptions are not met, or when it can be assumed that ferritin-inflammation relationships within a subpopulation may deviate from average trends.
INTRODUCTION:Polyserositis is described as inflammation with effusion of more than one serous membrane. There is very little published literature linking it to COVID-19 as a late complication.OBJECTIVE:Present and describe a case of post-COVID-19 polyserositis.METHODS:Data were collected from the medical record of a female patient admitted for fainting spells and marked weakness. The patient underwent a clinical evaluation, additional hematology, imaging and histopathology tests, and a surgical procedure. The new index, called the abdominal adipose deposit index, was obtained by multiplying the subcutaneous fat thickness by visceral fat thickness, both measured by ultrasound. A cutoff point was established that facilitated discernment of an unhealthy phenotype: normal weight but metabolically obese, a cardiometabolic risk factor.RESULTS:We present the case of a 57-year-old female patient admitted to hospital for fainting spells and marked weakness, four months after COVID-19 infection. She also had a history of obesity, asthma, type 2 diabetes mellitus and a cholecystectomy in December 1992 for gallstones. Clinical assessment revealed pericardial effusion and bilateral pleural effusion, in addition to a tumor-like lesion outside the pericardium, proximal to the right ventricular wall. A surgical procedure and findings from additional tests led to diagnoses of thymic remnants and polyserositis.CONCLUSIONS:This is a case of polyserositis in a post-COVID-19 patient. After other causes of polyserositis were ruled out, and since there is a likely physiological and pathogenic mechanism operating between the two diseases, the polyserositis was determined to be a late complication of COVID-19. To date, it is the second case reported in the world and the first reported in Cuba.
As 2021 drew to a close, Cuba struggled to contain the highly transmissible omicron variant of SARS-CoV-2, braced for a new wave of infections and kept a close eye on other variants of concern popping up around the world-a common experience to countries everywhere as we head into the second year of the pandemic. In Cuba, however, there is one marked difference making all the difference: by early January, 87% of the population was fully vaccinated using a three-dose schedule of vaccines developed and produced on the island.[1] This massive vaccination campaign is complemented by a rapid booster rollout-also using Cuban vaccines-that began in December 2021 and was ongoing as we finalized this issue. The island nation was able to achieve the third highest COVID-19 vaccination rate in the world[2] after decades of scientific investment, research, discovery and innovation; regulatory oversight and compliance; professional training; and increased production capacity. But a vaccine is only as effective as the health system charged with administering it-in a safe and timely manner, to as many people as possible. Here too, Cuba has decades of experience, including a national pediatric immunization program where 98% of children under 5 are immunized against 13 diseases,[3] an annual polio vaccination campaign (both launched in 1962 and uninterrupted since) and campaigns to contain epidemics such as H1N1. When the first COVID-19 cases were detected on the island in March 2020, Cuba harnessed this vaccine experience, making a hard tack towards developing its own vaccines. Two of the main protagonists in the country's biotechnology development, the Finlay Vaccine Institute (IFV) and the Genetic Engineering and Biotechnology Center (CIGB), both with several groundbreaking preventive and therapeutic vaccines in their portfolios, led the search for a vaccine. Today, Cuba has three vaccines authorized for emergency use-Soberana 02 and Soberana Plus developed by IFV, and Abdala, developed by CIGB. Schedules with these vaccines have demonstrated more than 90% efficacy in clinical trials,[4] and after regulatory approval for emergency use, became the backbone of Cuban COVID-19 vaccination efforts. A fourth vaccine, Mambisa (CIGB), administered nasally, and a fifth, Soberana 01 (IFV) are still in clinical trials. For this installment in MEDICC Review's series spotlighting leading women of Cuban science, we sat down with Dr Verena Muzio, Director of Clinical Research at CIGB. A pioneer of Cuba's biotechnology sector, she is an immunologist with a doctorate in biological sciences. Her professional trajectory began researching the genetically engineered hepatitis B surface antigen that led to the development of Cuba's recombinant hepatitis B vaccine in 1989. The same technological platform used in this vaccine was used to develop CIGB's Abdala vaccine against SARS-CoV-2-part of the reason Cuba was able to secure a vaccine so quickly. A phase 3 clinical trial determined a 92.28% efficacy rate for Abdala, with results to appear in forthcoming publications.
Globally, SARS CoV-2 omicron variant has led to a notable increase of COVID-19 diagnoses, although with less severe clinical manifestations and decreased hospitalizations. The omicron wave swelled faster than previous waves, completely displacing the delta variant within weeks, and creating worldwide concern about final, successful pandemic control. Some authors contend that symptoms associated to omicron differ from 'traditional' symptoms and more closely resemble those of the common cold. One major COVID-19 symptom frequent with other variants-loss of taste and smell-is rarely present with omicron. This may be of interest, since it has also been suggested that direct SARS-CoV-2 invasion into the brainstem through the olfactory nerves by transsynaptic pathways could provide one explanation for the acute respiratory distress syndrome refractory to treatment. Brainstem infection by SARS-CoV-2 can severely damage the respiratory center, triggering functional deviations that affect involuntary respiration, leading to acute respiratory distress syndrome refractory to treatment, the main cause of death in COVID-19 patients. A shift in the omicron SARS-CoV-2 entry pathway from cell-surface fusion, triggered by TMPRSS2, to cathepsin-dependent fusion within the endosome, may affect transmission, cellular tropism and pathogenesis. Therefore, we can hypothesize that this entrance modification may impact transmission from the olfactory nerve to the brainstem through transsynaptic pathways. A decrement of the virus's direct invasion into the brainstem could diminish respiratory center dysfunction, reducing acute respiratory distress syndrome and the need for mechanical ventilation.
