The Epidemiological Impact of Dengue in Colombia: A Systematic Review.

Dengue is the most important viral vector-borne disease in the tropics, with Colombia being one of the most affected countries. In this context, it is essential to identify and synthesize the existing evidence on the epidemiology of dengue in Colombia. A systematic review (PROSPERO CRD42021257985) was conducted by searching for epidemiological data in populations with suspected or confirmed dengue in Colombia from 2012 to 2020. We searched PubMed, EMBASE, the Cochrane Library, the LILACS, and SciELO databases, and 104 publications out of 1,234 records were selected. The dengue annual incidence rate varied through the years without a clear trend. The lowest annual incidence rate was observed in 2017 (90.7 per 100,000 population) and the highest in 2013 (476.2 per 100,000 population). The proportion of severe cases in the same period ranged between 0.89% in 2016 and 2.7% in 2012. The four dengue virus (DENV) serotypes co-circulated in the country, and DENV-2 was the predominant serotype. Fifty percent of dengue cases occurred in people under 20 years, and those between 5 and 14 years had the highest incidence rate. The mortality rate for all dengue cases ranged from 0.07% in 2020 to 0.16% in 2012 and 2015. In conclusion, dengue is a hyperendemic disease in Colombia with the circulation of four serotypes. New strategies must be implemented to prevent the contagion and impact of the disease on the population at risk.

Seroprevalence of bovine leukemia virus and association with bovine infectious abortion in Creole breeds from tropical grazing herds in the Colombian Caribbean.

Background and Aim: In the Caribbean region of Colombia, the concomitance of endemic infectious agents is a common problem, and coinfections are possible, increasing the complexity of cattle herds' sanitary, reproductive, and productive problems. This study aimed to estimate the seroprevalence of bovine leukemia virus and its association with bovine infectious abortion in grazing Creole breeds from tropical herds in the Colombian Caribbean. Materials and Methods: For the determination of bovine leukemia virus (BLV), bovine viral diarrhea virus (BVDV), bovine herpes virus-1 (BoHV-1), and Neospora Caninum (NC), the enzyme-linked immunosorbent assay technique was used. Matrix analysis was performed to represent multiple seroprevalence in the same cow. To explore the association between the seroprevalence of BLV and bovine infectious abortion agents, a multivariate logistic regression model was used. Results: The seroprevalence was as follows: BLV 30.78%, BVDV 33.01%, BoHV-1 12.85%, and NC 8.96%. In the multivariate logistic regression model, seroprevalence of BVDV (OR 10.8; 95% CI: 7.5-15.6) and seroprevalence of BoHV-1 (OR 1.8; 95% CI: 1.1-3.0) were associated with the seroprevalence of BLV. Conclusion: Animals infected with BLV are more susceptible to coinfections with BVDV and BoHV-1. Implementing healthy measures against these two immunosuppressive infections could enhance the hygiene of numerous cattle herds. This study was designed as a retrospective cross-sectional study, which limits the ability to confirm that BLV is the primary infection. Further studies to confirm the primary infection of BLV with an active viral coinfection are necessary and the factors associated with these phenomena.

Biotechnological sovereignty is not a mere nationalist concept, it is a necessity for Colombia and Latin America.

During the pandemic, Latin American countries suffered the collapse of their health systems. This was caused by the high demand for care of patients infected with SARS-CoV-2, which was added to the care of patients with other diseases. The significant increase in demand for health services caused medical and laboratory supplies to decline rapidly. The COVID-19 pandemic exacerbated a health crisis in several developing countries, mainly caused by insufficient systematic policies for integrating scientific knowledge. The current Colombian government must formulate a Biotechnological or Biosecurity Sovereignty Law that guarantees scientific autonomy, ensuring that Colombia is self-sufficient in Science, Technology, and Innovation. Colombian government should also focus on establishing and developing pharmaceutical chemical production by acquiring active chemical ingredients from other countries. This strategy could reduce the production costs and final prices of medicines, as well as generate high-level employment and wealth for the country. In this way, the Colombian government could prevent shortage of essential medicines and excessive price increases by commercial intermediation. In conclusion, the manuscript focuses on the lack of biotechnological sovereignty in Colombia. We propose a model of a Latin American Science and Technology ecosystem to achieve biotechnological sovereignty via state funding of research, strengthening universities, and fostering participation among private companies and Ministries of Science, Education, Trade, and Health. Scientific autonomy based on innovative processes that strengthen biotechnological independence can contribute to the economy by generating gross added value, creating high-quality employment, and facilitating the appropriation and social dissemination of knowledge, and cost reduction.

Unexpected arboviruses found in an epidemiological surveillance of acute tropical febrile syndrome in the department of Meta, Eastern Colombia.

BACKGROUND: Nonspecific acute tropical febrile illnesses (NEATFI) are common in the Latin American tropics. Dengue, Chikungunya, Zika, Mayaro, and Usutu, among others, can coexist in the American tropics. This study aimed to surveil the arboviruses that cause| acute febrile syndrome in patients in the Meta department, Colombia. METHODS: Between June 2021 and February 2023, an epidemiological surveillance study was conducted in the Llanos of the Meta department in Eastern Colombia. RESULTS: One hundred patients in the acute phase with typical prodromal symptoms of NEATFI infection who attended the emergency department of the Villavicencio Departmental Hospital were included. ELISA tests were performed for Dengue, Usutu, Chikungunya, and Mayaro. RT-qPCR was performed to detect the arboviruses Usutu, Dengue, Zika, Mayaro, and Oropouche. The seroprevalence for the Chikungunya, Mayaro, and Usutu viruses was 41 % (28/68), 40 % (27/67), and 62 % (47/75), respectively. Seroconversion for Chikungunya was observed in one patient; two seroconverted to Mayaro and one to Usutu. The NS5 gene fragment of the Usutu virus was detected in nine febrile patients. RT-qPCR of the remaining arboviruses was negative. The clinical symptoms of the nine Usutu-positive patients were very similar to those of Dengue, Chikungunya, Zika, and Mayaro infections. CONCLUSIONS: The pervasive detection of unexpected viruses such as Usutu and Mayaro demonstrated the importance of searching for other viruses different from Dengue. Because Usutu infection and Mayaro fever have clinical features like Dengue, a new algorithm should be proposed to improve the accuracy of acute tropical fevers.

Hard ticks (Ixodida: Ixodidae) in the Colombian Caribbean harbor the Jingmen tick virus: an emerging arbovirus of public health concern.

BACKGROUND: Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. METHODS: Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. RESULTS: A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. CONCLUSIONS: JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases.

Biotechnological sovereignty is not a mere nationalist concept, it is a necessity for Colombia and Latin America / Soberanía biotecnológica no es un mero concepto nacionalista, pero una necesidad para Colombia y América Latina / A soberania biotecnológica não é um mero conceito nacionalista, é uma necessidade para a Colômbia e a América Latina

Abstract: During the pandemic, Latin American countries suffered the collapse of their health systems. This was caused by the high demand for care of patients infected with SARS-CoV-2, which was added to the care of patients with other diseases. The significant increase in demand for health services caused medical and laboratory supplies to decline rapidly. The COVID-19 pandemic exacerbated a health crisis in several developing countries, mainly caused by insufficient systematic policies for integrating scientific knowledge. The current Colombian government must formulate a Biotechnological or Biosecurity Sovereignty Law that guarantees scientific autonomy, ensuring that Colombia is self-sufficient in Science, Technology, and Innovation. Colombian government should also focus on establishing and developing pharmaceutical chemical production by acquiring active chemical ingredients from other countries. This strategy could reduce the production costs and final prices of medicines, as well as generate high-level employment and wealth for the country. In this way, the Colombian government could prevent shortage of essential medicines and excessive price increases by commercial intermediation. In conclusion, the manuscript focuses on the lack of biotechnological sovereignty in Colombia. We propose a model of a Latin American Science and Technology ecosystem to achieve biotechnological sovereignty via state funding of research, strengthening universities, and fostering participation among private companies and Ministries of Science, Education, Trade, and Health. Scientific autonomy based on innovative processes that strengthen biotechnological independence can contribute to the economy by generating gross added value, creating high-quality employment, and facilitating the appropriation and social dissemination of knowledge, and cost reduction.

Resumen: Durante la pandemia, los países latinoamericanos vieron colapsar sus sistemas de salud. Esto se debió a la alta demanda de atención para las personas contagiadas con SARS-CoV-2 y a la atención de pacientes con otros tipos de enfermedades. El aumento significativo de la demanda de los servicios de salud llevó a la rápida disminución de los suministros médicos y de laboratorio. La pandemia de la COVID-19 intensificó la crisis sanitaria en los países en desarrollo, principalmente por una política sistemática e insuficiente de apropiación del conocimiento científico. Si el actual gobierno colombiano formulara una Ley de Soberanía Biotecnológica o de Bioseguridad por la cual se garantizaría la autonomía científica, esto conduciría a una autonomía de Colombia en Ciencia, Tecnología e Innovación. El Gobierno de Colombia también debería centrarse en fomentar y desarrollar la producción de productos químicos farmacéuticos mediante el abastecimiento de ingredientes químicos activos de otros países. Esta estrategia favorece la reducción de costos de producción y del precio final de los medicamentos, además de generar empleos de alto nivel y riqueza para el país. De esta manera, no habría escasez de medicamentos esenciales, ni alzas excesivas de precios en la intermediación comercial. Pero, la realidad es que hay una débil soberanía biotecnológica en Colombia. En este texto se propone un modelo de ecosistema basado en Ciencia y Tecnología para que Latinoamérica logre la soberanía biotecnológica mediante el financiamiento estatal a la investigación en universidades, con la participación de entidades privadas y Ministerios de Ciencia, Educación, Comercio y Salud. La autonomía científica se basa en procesos de innovación que implican el fortalecimiento de la autonomía biotecnológica.

Resumo: Durante a pandemia, os países latino-americanos sofreram o colapso de seus sistemas de saúde. Isso foi causado pela alta demanda de atendimento aos infectados pelo SARS-CoV-2, que somou-se, em paralelo, ao atendimento de pacientes com outros tipos de doenças. O aumento significativo na demanda por serviços de saúde levou à rápida diminuição dos suprimentos médicos e laboratoriais. A pandemia de COVID-19 acelerou, nos países em desenvolvimento, uma crise sanitária causada principalmente por uma política sistemática e insuficiente de apropriação do conhecimento científico. O atual governo colombiano deve formular uma Lei de Soberania Biotecnológica ou de Biossegurança que garanta a autonomia científica, o que leva à autonomia que garante que a Colômbia seja autossuficiente em Ciência, Tecnologia e Inovação. O governo da Colômbia também deve se concentrar em estabelecer e desenvolver a produção de produtos químicos farmacêuticos, adquirindo ingredientes químicos ativos de outros países. Essa estratégia reduz os custos de produção e o preço final dos medicamentos, além de gerar empregos de alto nível e riqueza para o país. Desta forma, não haveria escassez de medicamentos essenciais, nem estaríamos sujeitos a aumentos excessivos de preços por intermediação comercial. Em conclusão, o manuscrito foca na fracassada soberania biotecnológica na Colômbia. Propomos um modelo de ecossistema latino-americano de Ciência e Tecnologia para alcançar a soberania biotecnológica por meio do financiamento estatal do fortalecimento da pesquisa das universidades, com a participação de empresas privadas e Ministérios da Ciência, Educação, Comércio e Saúde. A autonomia científica é baseada em processos de inovação que fortalecem a autonomia biotecnológica.

Borrelia puertoricensis in opossums (Didelphis marsupialis) from Colombia.

BACKGROUND: The genus Borrelia comprises pathogenic species of bacteria that pose a significant risk to public health. Borrelia spp. are emerging or reemerging infectious agents worldwide with complex transmission cycles, and many species use rodents as vertebrate reservoir hosts. Spirochetes morphologically compatible with Borrelia have been recurrently observed in opossums; however, there is currently a lack of genetic evidence confirming infection or supporting that these marsupials are hosts of Borrelia spirochetes. METHODS: During 2017, 53 serum samples of Didelphis marsupialis from the municipality of Colosó (department of Sucre, Colombia) were collected and allocated in a serum bank. DNA extracted from the serum samples was submitted to a Borrelia genus-specific real-time PCR targeting the 16S rRNA gene. Positive samples were subsequently derived from semi-nested PCR protocols to obtain large fragments of the 16S rRNA and flaB genes. Obtained amplicons were subjected to Sanger sequencing. One positive sample was randomly selected for next-generation sequencing (NGS). Obtained reads were mapped to genomes of Borrelia spp. and sequences of two genes used in a multilocus sequence typing scheme retrieved for taxonomic assignment and phylogenetic analyses. RESULTS: Overall, 18.8% (10/53) of the samples were positive by qPCR. Of them, 80% (8/10) and 60% (6/10) were positive for the 16S rRNA and flaB genes after semi-nested PCRs, respectively. Bioinformatic analysis of one sample sequenced with NGS yielded 22 reads of genus Borrelia with different sizes. Two housekeeping genes, rplB and pyrG, were recovered. Nucleotide pairwise comparisons and phylogenetic analyses of 16S rRNA, flaB, rplB and pyrG genes showed that the Borrelia sp. found in opossums from Colosó corresponded to Borrelia puertoricensis. CONCLUSIONS: We describe the first molecular evidence to our knowledge of B. puertoricensis in Colombia, specifically in opossums, and the first detection of this spirochete in a vertebrate host since its isolation from Ornithodoros puertoricensis in Panama. This detection is also relevant because of the epidemiological importance of opossums as reservoirs of zoonotic diseases to humans.

Etiologies of Zoonotic Tropical Febrile Illnesses That Are Not Part of the Notifiable Diseases in Colombia.

In Colombia, tropical febrile illnesses represent one of the most important causes of clinical attention. Febrile illnesses in the tropics are mainly zoonotic and have a broad etiology. The Colombian surveillance system monitors some notifiable diseases. However, several etiologies are not monitored by this system. In the present review, we describe eleven different etiologies of zoonotic tropical febrile illnesses that are not monitored by the Colombian surveillance system but have scientific, historical, and contemporary data that confirm or suggest their presence in different regions of the country: Anaplasma, Arenavirus, Bartonella, relapsing fever group Borrelia, Coxiella burnetii, Ehrlichia, Hantavirus, Mayaro virus, Orientia, Oropouche virus, and Rickettsia. These could generate a risk for the local population, travelers, and immigrants, due to which they should be included in the mandatory notification system, considering their importance for Colombian public health.

Genomic epidemiology of SARS-CoV-2 variants during the first two years of the pandemic in Colombia.

BACKGROUND: The emergence of highly transmissible SARS-CoV-2 variants has led to surges in cases and the need for global genomic surveillance. While some variants rapidly spread worldwide, other variants only persist nationally. There is a need for more fine-scale analysis to understand transmission dynamics at a country scale. For instance, the Mu variant of interest, also known as lineage B.1.621, was first detected in Colombia and was responsible for a large local wave but only a few sporadic cases elsewhere. METHODS: To better understand the epidemiology of SARS-Cov-2 variants in Colombia, we used 14,049 complete SARS-CoV-2 genomes from the 32 states of Colombia. We performed Bayesian phylodynamic analyses to estimate the time of variants' introduction, their respective effective reproductive number, and effective population size, and the impact of disease control measures. RESULTS: Here, we detect a total of 188 SARS-CoV-2 Pango lineages circulating in Colombia since the pandemic's start. We show that the effective reproduction number oscillated drastically throughout the first two years of the pandemic, with Mu showing the highest transmissibility (Re and growth rate estimation). CONCLUSIONS: Our results reinforce that genomic surveillance programs are essential for countries to make evidence-driven interventions toward the emergence and circulation of novel SARS-CoV-2 variants.

Colombia reported its first COVID-19 case on 6th March 2020. By April 2022, the country had reported over 6 million infections and over 135,000 deaths. Here, we aim to understand how SARS-CoV-2, the virus that causes COVID-19, spread through Colombia over this time and how the predominant version of the virus (variant) changed over time. We found that there were multiple introductions of different variants from other countries into Colombia during the first two years of the pandemic. The Gamma variant was dominant earlier in 2021 but was replaced by the Delta variant. The Mu variant had the highest potential to be transmitted. Our findings provide valuable insights into the pandemic in Colombia and highlight the importance of continued surveillance of the virus to guide the public health response.

Not all respiratory infections were SARS-CoV-2 during the pandemic, analysis in a clinic on the Colombian Caribbean coast.

INTRODUCTION: Acute Respiratory Infections (ARIs) are considered one of the leading causes of morbidity and mortality worldwide. Children under five and older adults are most likely to die from this cause. OBJECTIVE: To describe the behavior of infection by respiratory viruses other than SARS-CoV-2 during the pandemic in a clinic in the Colombian Caribbean. METHODS: This descriptive and retrospective study evaluates the characteristics, associated comorbidities, and requirements of hospitalization or Intensive Care Unit in patients diagnosed with respiratory viral infections treated at IMAT Oncomedica clinic from July 2020 to August 2022. RESULTS: This study evaluated 351 patients with respiratory symptoms, observing an exponential increase in cases of respiratory infection as of April 2022, with a high proportion of syncytial virus infections mainly in children under 18 years of age (22.1%) and Human Rhinovirus/Enterovirus in patients with solid tumors and hematological disorders (48.8%), the latter was associated with a higher rate of hospitalization and ICU requirement in the individuals evaluated. CONCLUSIONS: Respiratory viruses other than SARS-CoV-2, such as Rhino/Enterovirus, RSV, and adenovirus, are circulating in the population at a clinic on the Colombian Caribbean coast. The findings should motivate public health authorities to conduct more thorough surveillance in the rest of the state.

Case Report: A Case of Sepsis due to Shewanella algae Infection in the Colombian Caribbean.

Shewanella algae is an opportunistic Gram-negative bacillus that inhabits marine ecosystems and can cause sepsis in humans. This case report describes an 80-year-old obese woman with liver cirrhosis who presented with neurological and respiratory impairment. Shewanella algae were isolated in the blood cultures. Due to age and comorbidities, sepsis could be the cause of the patient's fatal outcome. Shewanella algae infection is a risk for immunocompromised people in the tropics.

Burden of COVID-19 in Córdoba, A Department of Colombia: Results of Disability-Adjusted Life-Years: Carga de COVID-19 en Córdoba, un Departamento de Colombia: Resultados de los Años de Vida Ajustados por Discapacidad.

OBJECTIVES: This study aimed to estimate the burden of acute COVID-19 in Córdoba, one of the most affected departments (states) in Colombia, through the estimation of disability-adjusted life-years (DALYs). METHODS: DALYs were estimated based on the number of cases of severe acute respiratory syndrome coronavirus 2 infection cases reported by official Colombian sources. A transition probability matrix among severity states was calculated using data obtained from a retrospective cohort that included 1736 COVID-19 confirmed subjects living in Córdoba. RESULTS: Córdoba had 120.23 deaths per 100 000 habitants during the study period (March 2020 to April 2021). Estimated total DALYs were 49 243 (2692 DALYs per 100 000 inhabitants), mostly attributed to fatal cases (99.7%). On average, 25 years of life were lost because of death by this infection. A relevant proportion of years of life lost because of COVID-19 (46.6%) was attributable to people < 60 years old and was greater in men. People ≥ 60 years old showed greater risk of progression to critical state than people between the age of 35 and 60 years (hazard ratio 2.5; 95% confidence interval 2.5-12.5) and younger than 35 years (9.1; 95% confidence interval 4.0-20.6). CONCLUSION: In Córdoba, premature mortality because of COVID-19 was substantially represented by people < 60 years old and was greater in males. Our data may be representative of Latin American populations with great infection spread during the first year of the pandemic and contribute to novel methodological aspects and parameter estimations that may be useful to measure COVID-19 burden in other countries of the region.

Molecular evidence of Borrelia spp. in bats from Córdoba Department, northwest Colombia.

BACKGROUND: The genus Borrelia is composed of two well-defined monophyletic groups, the Borrelia burgdorferi sensu lato complex (Bb) and the relapsing fever (RF) group borreliae. Recently, a third group, associated with reptiles and echidnas, has been described. In general, RF group borreliae use rodents as reservoir hosts; although neotropical bats may also be involved as important hosts, with scarce knowledge regarding this association. The objective of this study was to detect the presence of Borrelia spp. DNA in bats from the department of Córdoba in northwest Colombia. METHODS: During September 2020 and June 2021, 205 bats were captured in six municipalities of Córdoba department, Colombia. Specimens were identified using taxonomic keys and DNA was extracted from spleen samples. A Borrelia-specific real-time PCR was performed for the 16S rRNA gene. Fragments of the 16S rRNA and flaB genes were amplified in the positive samples by conventional PCR. The detected amplicons were sequenced by the Sanger method. Phylogenetic reconstruction was performed in IQ-TREE with maximum likelihood based on the substitution model TPM3+F+I+G4 with bootstrap values deduced from 1000 replicates. RESULTS: Overall, 10.2% (21/205) of the samples were found positive by qPCR; of these, 81% (17/21) and 66.6% (14/21) amplified 16S rRNA and flaB genes, respectively. qPCR-positive samples were then subjected to conventional nested and semi-nested PCR to amplify 16S rRNA and flaB gene fragments. Nine positive samples for both genes were sequenced, and seven and six sequences were of good quality for the 16S rRNA and flaB genes, respectively. The DNA of Borrelia spp. was detected in the insectivorous and fruit bats Artibeus lituratus, Carollia perspicillata, Glossophaga soricina, Phyllostomus discolor, and Uroderma sp. The 16S rRNA gene sequences showed 97.66-98.47% identity with "Borrelia sp. clone Omi3," "Borrelia sp. RT1S," and Borrelia sp. 2374; the closest identities for the flaB gene were 94.02-98.04% with "Borrelia sp. Macaregua." For the 16S rRNA gene, the phylogenetic analysis showed a grouping with "Candidatus Borrelia ivorensis" and "Ca. Borrelia africana," and for the flaB gene showed a grouping with Borrelia sp. Macaregua and Borrelia sp. Potiretama. The pathogenic role of the Borrelia detected in this study is unknown. CONCLUSIONS: We describe the first molecular evidence of Borrelia spp. in the department of Córdoba, Colombia, highlighting that several bat species harbor Borrelia spirochetes.

Laboratory life cycle of Ornithodoros puertoricensis (Ixodida: Argasidae) collected in the Colombian Caribbean.

Three studies on the biology of Ornithodoros puertoricensis are available in the literature, using different hosts and incubation temperatures. In a previous study, we identified O. puertoricensis in the Colombian Caribbean. The aim of the present work was to analyze life cycle data along one generation from these specimens under laboratory conditions. Eggs of O. puertoricensis were collected in between fragments of bahareque material in a rural dwelling in the municipality of Planeta Rica (Córdoba Department, Colombia), and transported to the laboratory. All post-egg stages (i.e., larvae, nymphs, and adults) were incubated at 27 °C and 85% RH and fed on laboratory mice (Mus musculus). Sixteen engorged larvae were obtained to start a laboratory colony. Average feeding period for larvae was 4.6 days (4-5). The first nymphal instar (N1) did not require feeding and the subsequent nymphal stages (N2, N3, and N4) and adults had feeding periods ranging from 55 to 75 min. Average pre-molting period in nymphs was 15 days (10-21). Most of the N3 molted to males and all N4 molted to females. Two gonotrophic cycles were recorded: the first had a preoviposition period of 12 days (7-18) and produced 190 eggs (171-223), the second lasted 6.6 days (6-7) and produced 146 eggs (104-201). The mean life cycle duration (from parental eggs to F1 eggs) was 70.7 days (58.7-82.7) without fasting periods. The collected data agree with previous studies even with differences in hosts and maintenance conditions.

Seroprevalence of antibodies against to SARS-CoV 2 in umbilical cord blood in two hospital centers in Córdoba and Sucre, Colombia.

INTRODUCTION: Pregnant women continue to be vulnerable to COVID-19, and their immunosuppressed state could put them at greater risk of developing more severe forms of the disease. In Colombia and Latin America, there are few studies on the immune response of the newborn against SARS-CoV-2. AIM: To determine the prevalence of SARS-CoV-2 infection in umbilical cord blood in two hospital centers in Córdoba and Sucre. METHODS: Between March and June 2021, a prospective descriptive cross-sectional study was carried out. Two hospitals from the departments of Córdoba and Sucre, located in the Northwest Caribbean area of Colombia, participated. Three hundred sixty umbilical cord blood samples were taken at the two hospitals. A commercial ELISA was performed to detect total IgG, IgM, and IgA antibodies against the N protein of SARS-CoV-2. The ethics committee approved the study of the participating institutions. RESULTS: Of 3.291 women who gave birth in the hospital centers included in the study, 360 (11%) participated. Complete clinical data were obtained for 223 women. The mean age of the women was 24 years (range, 15-42). 29.4% (106/360) of the umbilical cord samples had total antibodies against SARS-CoV-2. Pregnant women did not have blood samples taken. 58% of the women were asymptomatic. There was no association between umbilical cord samples, clinical, epidemiological characteristics, and serological response to antibodies to SARS-CoV-2 (p > 0.05). CONCLUSIONS: The prevalence of umbilical cord blood samples was 29.4% for total SARS-CoV-2 antibodies. The study provides essential aspects for the epidemiological approach to neonates infected with SARS-CoV-2.

Immunogenicity and safety of a RBD vaccine against SARS-CoV-2 in a murine model.

INTRODUCTION: Although more than half of the world's population is already vaccinated, the appearance of new variants of concern puts public health at risk due to the generation of new immunogens against the virus as a crucial and relevant strategy in the control of these new variants. METHODS: A preclinical study used a potential vaccine candidate (RBD, SARS-CoV-2). Four groups of BALB/c mice were used, a control group, an adjuvant group, a group inoculated with one dose of RBD subunit protein, and the fourth group inoculated with two doses of RBD subunit protein. RESULTS: No inflammatory or cellular changes were shown in the mice's anatomopathological evaluation. Higher kinetics and 75% seroconversion were obtained in the mice inoculated with two doses of RBD (P < 0.0001). CONCLUSIONS: The application of two doses of the RBD vaccine candidate in BALB/c mice proved safe and immunogenic against SARS-CoV-2.

SARS-CoV-2 in a tropical area of Colombia, a remarkable conversion of presymptomatic to symptomatic people impacts public health.

BACKGROUND: The ability of SARS-CoV-2 to remain in asymptomatic individuals facilitates its dissemination and makes its control difficult. OBJECTIVE: To establish a cohort of asymptomatic individuals, change to the symptomatic status, and determine the most frequent clinical manifestations.  METHODS: Between April 9 and August 9, 2020, molecular diagnosis of SARS-CoV-2 infection was confirmed in 154 asymptomatic people in contact with subjects diagnosed with COVID-19. Nasopharyngeal swabs were performed on these people in different hospitals in Córdoba, the Caribbean area of Colombia. The genes E, RdRp, and N were amplified with RT-qPCR. Based on the molecular results and the Cq values, the patients were subsequently followed up through telephone calls to verify their health conditions. RESULTS: Overall, of 154 asymptomatic individuals, 103 (66.9%) remained asymptomatic, and 51 (33.1%) changed to symptomatic. The most frequent clinical manifestations in young people were anosmia and arthralgia. Adults showed cough, ageusia, and odynophagia; in the elderly were epigastralgia, dyspnea, and headache. Mortality was 8%. CONCLUSIONS: A proportion of 33% of presymptomatic individuals was found, of which four of them died. This high rate could indicate a silent transmission, contributing significantly to the epidemic associated with SARS-CoV-2.