Interim Effectiveness Estimates of 2024 Southern Hemisphere Influenza Vaccines in Preventing Influenza-Associated Hospitalization - REVELAC-i Network, Five South American Countries, March-July 2024.

To reduce influenza-associated morbidity and mortality, countries in South America recommend annual influenza vaccination for persons at high risk for severe influenza illness, including young children, persons with preexisting health conditions, and older adults. Interim estimates of influenza vaccine effectiveness (VE) from Southern Hemisphere countries can provide early information about the protective effects of vaccination and help guide Northern Hemisphere countries in advance of their season. Using data from a multicountry network, investigators estimated interim VE against influenza-associated severe acute respiratory illness (SARI) hospitalization using a test-negative case-control design. During March 13-July 19, 2024, Argentina, Brazil, Chile, Paraguay, and Uruguay identified 11,751 influenza-associated SARI cases; on average, 21.3% of patients were vaccinated against influenza, and the adjusted VE against hospitalization was 34.5%. The adjusted VE against the predominating subtype A(H3N2) was 36.5% and against A(H1N1)pdm09 was 37.1%. These interim VE estimates suggest that although the proportion of hospitalized patients who were vaccinated was modest, vaccination with the Southern Hemisphere influenza vaccine significantly lowered the risk for hospitalization. Northern Hemisphere countries should, therefore, anticipate the need for robust influenza vaccination campaigns and early antiviral treatment to achieve optimal protection against influenza-associated complications.

Human Papillomavirus (HPV) Infection and Risk Behavior in Vaccinated and Non-Vaccinated Paraguayan Young Women.

Cervical cancer is a global health concern and ranks fourth among the most prevalent cancers in women worldwide. Human papillomavirus (HPV) infection is a known precursor of cervical cancer and preventive measures include prophylactic vaccines. This study focused on sexually active Paraguayan women aged 18-25 years, exploring the intersection of HPV vaccination and sexual behavior. Among 254 participants, 40.9% received the Gardasil-4 vaccine, with no significant differences in sexual behavior between the vaccinated and unvaccinated sexually active groups. However, a notable decrease in the prevalence of HPV among the vaccinated women highlights the efficacy of this vaccine in reducing infections. The prevalence of any HPV type was 37.5% in vaccinated participants compared to 56.7% in unvaccinated participants (p = 0.0026). High-risk HPV types showed a significant difference, with a prevalence of 26.0% in vaccinated women compared with 52.7% in unvaccinated women (p < 0.001). Although a potential decline in genital warts was observed among the vaccinated individuals, statistical significance (p = 0.0564) was not reached. Despite the challenges in achieving high vaccination coverage, the observed reduction in HPV prevalence underscores the importance of ongoing monitoring, healthcare professional recommendations, and comprehensive risk management. These findings contribute to dispelling concerns about HPV vaccination influencing sexual behavior, advocating further large-scale research to explore the impact of vaccines on various HPV types and potential cross-protection.

Characterization of Dengue Virus 4 Cases in Paraguay, 2019-2020.

In 2019-2020, dengue virus (DENV) type 4 emerged to cause the largest DENV outbreak in Paraguay's history. This study sought to characterize dengue relative to other acute illness cases and use phylogenetic analysis to understand the outbreak's origin. Individuals with an acute illness (≤7 days) were enrolled and tested for DENV nonstructural protein 1 (NS1) and viral RNA by real-time RT-PCR. Near-complete genome sequences were obtained from 62 DENV-4 positive samples. From January 2019 to March 2020, 799 participants were enrolled: 253 dengue (14 severe dengue, 5.5%) and 546 other acute illness cases. DENV-4 was detected in 238 dengue cases (94.1%). NS1 detection by rapid test was 52.5% sensitive (53/101) and 96.5% specific (387/401) for dengue compared to rRT-PCR. DENV-4 sequences were grouped into two clades within genotype II. No clustering was observed based on dengue severity, location, or date. Sequences obtained here were most closely related to 2018 DENV-4 sequences from Paraguay, followed by a 2013 sequence from southern Brazil. DENV-4 can result in large outbreaks, including severe cases, and is poorly detected with available rapid diagnostics. Outbreak strains seem to have been circulating in Paraguay and Brazil prior to 2018, highlighting the importance of sustained DENV genomic surveillance.

COVID-19 vaccine effectiveness against hospitalizations in Paraguay, May 2021-April 2022: A test-negative design.

BACKGROUND: Vaccine effectiveness (VE) estimates vary by population characteristics and circulating variants. North America and Europe have generated many COVID-19 VE estimates but relied heavily on mRNA vaccines. Fewer estimates are available for non-mRNA vaccines and from Latin America. We aimed to estimate the effectiveness of several COVID-19 vaccines in preventing SARS-CoV-2-associated severe acute respiratory infection (SARI) in Paraguay from May 2021 to April 2022. METHODS: Using sentinel surveillance data from four hospitals in Paraguay, we conducted a test-negative case-control study to estimate COVID-19 vaccine effectiveness against SARI by vaccine type/brand and period of SARS-CoV-2 variant predominance (Gamma, Delta, Omicron). We used multivariable logistic regression adjusting for month of symptom onset, age group, and presence of ≥1 comorbidity to estimate the odds of COVID-19 vaccination in SARS-CoV-2 test-positive SARI case-patients compared to SARS-CoV-2 test-negative SARI control-patients. RESULTS: Of 4,229 SARI patients, 2,381 (56%) were SARS-CoV-2-positive case-patients and 1,848 (44%) were SARS-CoV-2-negative control-patients. A greater proportion of case-patients (73%; 95% CI: 71-75) than of control-patients (40%; 95% CI: 38-42) were unvaccinated. During the Gamma variant-predominant period, VE estimates for partial vaccination with mRNA vaccines and Oxford/AstraZeneca Vaxzevria were 90.4% (95% CI: 66.4-97.6) and 52.2% (95% CI: 25.0-69.0), respectively. During the Delta variant-predominant period, VE estimates for complete vaccination with mRNA vaccines, Oxford/AstraZeneca Vaxzevria, or Gamaleya Sputnik V were 90.4% (95% CI: 74.3-97.3), 83.2% (95% CI: 67.8-91.9), and 82.9% (95% CI: 53.0-95.2), respectively. The effectiveness of all vaccines declined substantially during the Omicron variant-predominant period. CONCLUSIONS: This study contributes to our understanding of COVID-19 VE in Latin America and to global understanding of vaccines that have not been widely used in North America and Europe. VE estimates from Paraguay can parameterize models to estimate the impact of the national COVID-19 vaccination campaign in Paraguay and similar settings.

End-of-season influenza vaccine effectiveness during the Southern Hemisphere 2022 influenza season - Chile, Paraguay, and Uruguay.

OBJECTIVES: This study estimated the 2022 end-of-season influenza vaccine effectiveness (VE) against severe acute respiratory illness (SARI) hospitalization in Chile, Paraguay, and Uruguay. METHODS: We pooled surveillance data from SARI cases in 18 sentinel surveillance hospitals in Chile (n = 9), Paraguay (n = 2), and Uruguay (n = 7) from March 16-November 30, 2022. VE was estimated using a test-negative design and logistic regression models adjusted for country, age, sex, presence of ≥1 comorbidity, and week of illness onset. VE estimates were stratified by influenza virus type and subtype (when available) and influenza vaccine target population, categorized as children, individuals with comorbidities, and older adults, defined per countries' national immunization policies. RESULTS: Among the 3147 SARI cases, there were 382 (12.1%) influenza test-positive case patients; 328 (85.9%) influenza case patients were in Chile, 33 (8.6%) were in Paraguay, and 21 (5.5%) were in Uruguay. In all countries, the predominant subtype was influenza A(H3N2) (92.6% of influenza cases). Adjusted VE against any influenza-associated SARI hospitalization was 33.8% (95% confidence interval: 15.3%, 48.2%); VE against influenza A(H3N2)-associated SARI hospitalization was 30.4% (95% confidence interval: 10.1%, 46.0%). VE estimates were similar across target populations. CONCLUSION: During the 2022 influenza season, influenza vaccination reduced the odds of hospitalization among those vaccinated by one-third. Health officials should encourage influenza vaccination in accordance with national recommendations.

Serum biomarkers and anti-flavivirus antibodies at presentation as indicators of severe dengue.

BACKGROUND: Dengue is the most common vector-borne viral disease worldwide. Most cases are mild, but some evolve into severe dengue (SD), with high lethality. Therefore, it is important to identify biomarkers of severe disease to improve outcomes and judiciously utilize resources. METHODS/PRINCIPAL FINDINGS: One hundred forty-five confirmed dengue cases (median age, 42; range <1-91 years), enrolled from February 2018 to March 2020, were selected from an ongoing study of suspected arboviral infections in metropolitan Asunción, Paraguay. Cases included dengue virus types 1, 2, and 4, and severity was categorized according to the 2009 World Health Organization guidelines. Testing for anti-dengue virus IgM and IgG and serum biomarkers (lipopolysaccharide binding protein and chymase) was performed on acute-phase sera in plate-based ELISAs; in addition, a multiplex ELISA platform was used to measure anti-dengue virus and anti-Zika virus IgM and IgG. Complete blood counts and chemistries were performed at the discretion of the care team. Age, gender, and pre-existing comorbidities were associated with SD vs. dengue with/without warning signs in logistic regression with odds ratios (ORs) of 1.07 (per year; 95% confidence interval, 1.03, 1.11), 0.20 (female; 0.05,0.77), and 2.09 (presence; 1.26, 3.48) respectively. In binary logistic regression, for every unit increase in anti-DENV IgG in the multiplex platform, odds of SD increased by 2.54 (1.19-5.42). Platelet count, lymphocyte percent, and elevated chymase were associated with SD in a combined logistic regression model with ORs of 0.99 (1,000/µL; 0.98,0.999), 0.92 (%; 0.86,0.98), and 1.17 (mg/mL; 1.03,1.33) respectively. CONCLUSIONS: Multiple, readily available factors were associated with SD in this population. These findings will aid in the early detection of potentially severe dengue cases and inform the development of new prognostics for use in acute-phase and serial samples from dengue cases.

Severity of influenza illness by seasonal influenza vaccination status among hospitalised patients in four South American countries, 2013-19: a surveillance-based cohort study.

BACKGROUND: Although several studies have reported attenuated influenza illness following influenza vaccination, results have been inconsistent and have focused predominantly on adults in the USA. This study aimed to evaluate the severity of influenza illness by vaccination status in a broad range of influenza vaccine target groups across multiple South American countries. METHODS: We analysed data from four South American countries (Argentina, Brazil, Chile, and Paraguay) participating in REVELAC-i, a multicentre, test-negative design, vaccine effectiveness network including 41 sentinel hospitals. Individuals hospitalised at one of these centres with severe acute respiratory infection were tested for influenza by real-time RT-PCR, and were included in the analysis if they had complete information about their vaccination status and outcomes of their hospital stay. We used multivariable logistic regression weighted by inverse probability of vaccination and adjusted for antiviral use, duration of illness before admission, and calendar week, to calculate the adjusted odds ratios (aORs) of intensive care unit (ICU) admission and in-hospital death (and combinations of these outcomes) among influenza-positive patients by vaccination status for three target groups: young children (aged 6-24 months), adults (aged 18-64 years) with pre-existing health conditions, and older adults (aged ≥65 years). Survival curves were used to compare length of hospital stay by vaccination status in each target group. FINDINGS: 2747 patients hospitalised with PCR-confirmed influenza virus infection between Jan 1, 2013, and Dec 8, 2019, were included in the study: 649 children (70 [10·8%] fully vaccinated, 193 [29·7%] partially vaccinated) of whom 87 (13·4%) were admitted to ICU and 12 (1·8%) died in hospital; 520 adults with pre-existing medical conditions (118 [22·7%] vaccinated), of whom 139 (26·7%) were admitted to ICU and 55 (10·6%) died in hospital; and 1578 older adults (609 [38·6%] vaccinated), of whom 271 (17·2%) were admitted to ICU and 220 (13·9%) died in hospital. We observed earlier discharge among partially vaccinated children (adjusted hazard ratio 1·14 [95% CI 1·01-1·29]), fully vaccinated children (1·24 [1·04-1·47]), and vaccinated adults with pre-existing medical conditions (1·78 [1·18-2·69]) compared with their unvaccinated counterparts, but not among vaccinated older adults (0·82 [0·65-1·04]). Compared with unvaccinated individuals, lower odds of ICU admission were found for partially vaccinated children (aOR 0·64 [95% CI 0·44-0·92]) and fully vaccinated children (0·52 [0·28-0·98]), but not for adults with pre-existing conditions (1·25 [0·93-1·67]) or older adults (0·88 [0·72-1·08]). Lower odds of in-hospital death (0·62 [0·50-0·78]) were found in vaccinated versus unvaccinated older adults, with or without ICU admission, but did not differ significantly in partially vaccinated (1·35 [0·57-3·20]) or fully vaccinated young children (0·88 [0·16-4·82]) or adults with pre-existing medical conditions (1·09 [0·73-1·63]) compared with the respective unvaccinated patient groups. INTERPRETATION: Influenza vaccination was associated with illness attenuation among those hospitalised with influenza, although results differed by vaccine target group. These findings might suggest that attenuation of disease severity might be specific to certain target groups, seasons, or settings. FUNDING: US Centers for Disease Control and Prevention. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Evaluación del sistema de vigilancia epidemiológica universal de las meningoencefalitis en Paraguay, 2016 / Evaluation of the universal epidemiological surveillance system for meningoencephalitis in Paraguay, 2016

Introducción.Las patologías neurológicas bacterianas constituyen un problema de salud mundial. En Paraguay, se emplean dos tipos de vigilancia epidemiológica para las infecciones meningocócicas: universal y centinela. Objetivo. Evaluar el sistema de vigilancia epidemiológica universal de las meningoencefalitis. Metodología.Estudio descriptivo transversal, basado en las directrices del Updated Guidelines for Evaluating Public Health Surveillance Systems-CDC-2001. Se analizó la base de datos del sistema nacional del 2016 seleccionando en forma aleatoria una muestra de 240 casos sospechosos de un total de 640 casos para evaluar los atributos de calidad de datos, aceptabilidad, oportunidad, sensibilidad y valor predictivo positivo (VPP), mediante una escala de calificaciones. Las medidas de frecuencias y tendencia central (media, mediana) fueron calculadas en Excel. Resultado.La evaluación de la calidad de los datos mostró una completitud de 95% e inconsistencia 4,2%. La aceptabilidad de los actores alcanzó 92%. La oportunidad de toma de muestra ≤ 24h (mediana= 1 día; rango= -31-35 días), el de diagnóstico ≤72h (mediana= 0 día; rango= 0-61 días) y la de notificación ha superado las 24h requeridas (mediana= 3 días; rango= 0-41 días). La sensibilidad del sistema fue 90% y elVPP 7,5%. Conclusión. El sistema es sensible en cuanto a la vigilancia clínica con un VPP bajo, la calidad de datos es excelente, aceptable por los actores, oportuna para la toma de muestras y de diagnóstico. Sin embargo, se debe mejorar la oportunidad de notificación.

Introduction. Bacterial neurological diseases are a global health problem. In Paraguay, two types of epidemiological surveillance are used for meningococcal infections: universal and sentinel. Objetive.The objective was to evaluate the universal epidemiological surveillance system for meningoencephalitis. Methodology:Cross-sectional descriptive study, following the guidelines of the Updated Guidelines for Evaluating Public Health Surveillance Systems-CDC-2001. The database of the national system of 2016 was analyzed. To evaluate the attributes: data quality, acceptability, timeliness, sensitivity and positive predictive value (PPV) the sample size of a total population of 640 was calculated using EpiInfo7.2.2.2, confidence level 95%. The minimum size studied was 240 suspected cases. The grading scale was developed. Random samples of records, frequency measurements and central tendency (mean, median) were calculated in Excel. Results:Epidemiological files were evaluated, the quality of the data in terms of completeness was 95% and inconsistency 4.2%. The acceptability of the actors reached 92%. The opportunity to take a sample ≤ 24 hours (Me= 1 day; R= -31-35 days), diagnosis ≤72h (Me= 0 days; R= 0-61 days) and notification has exceeded the required 24h (Me= 3 days; R= 0-41 days). The sensitivity of thesystem was found to be 90% with a PPV of 7.5%. Conclusion.In conclusion, the system is sensitive in terms of clinical surveillance with a low PPV, the data quality is excellent, acceptable by the actors, timely for sampling and diagnosis. However, the timeliness of notification needs to be improved.

Carga de influenza en la comunidad de Barrio Obrero. Paraguay / Burden of Influenza in the community of Barrio Obrero. Paraguay

La influenza (FLU) causa morbilidad grave y mortalidad. El objetivo del estudio fue evaluar la incidencia, la etiología y el uso de recursos para la gripe en un barrio de bajos ingresos de Asunción, Paraguay mediante un estudio de cohorte prospectiva de base poblacional con muestreo aleatorio estratificado de viviendas de julio a Octubre de 2013. El monitoreo de los hogares para la identificación de los casos de enfermedad tipo influenza (ETI) fue telefónico. En aquellos pacientes con ETI, se tomaron hisopados nasofaríngeos para RT-PCR e IFI. Se establecieron los factores de riesgo para ETI por la prueba de chi cuadrado considerándose significativa p<0,05; además se calculó RR con IC95%. De 8.279 viviendas, 401 familias (2.065 personas) fueron monitoreadas; se identificaron 141 casos de ETI que representa una incidencia de 6,8% (IC95%: 5,5-7,6%); el 56% de los casos buscaron atención médica, en su mayoría (80%) en servicios públicos. Se testaron 84% de los hisopados nasofaríngeos, siendo positivo en el 22% para virus respiratorios; 86% FLU (63% FLU A, 37% FLU B). Se encontró asociación (p< 0,001) entre enfermar de ETI y tener edad menor de 5 años (RR: 2,43 (1,68-3,49). Este es el primer estudio que da información sobre la carga de Influenza en Paraguay. El monitoreo telefónico resultó ser una buena estrategia para monitoreo de los hogares para la identificación de los casos de ETI. El virus de la Influenza fue el patógeno más común identificado, con una alta demanda de asistencia médica, lo que resulta una carga sustancial para los servicios de salud.

Influenza (FLU) causes severe morbidity and mortality. This study aimed to evaluate the incidence, etiology and use of resources for influenza in a low-income neighborhood in Asunción, Paraguay through a prospective population base cohort with stratified random sampling of houses from July to October 2013. Monitoring of cases of influenza-like illness (ILI) was by telephone. In ETI cases, nasopharyngeal swabs were collected for RT-PCR and IFI. Risk factors for ETI were established using chi square test at p≤0.05; RR with CI 95% was also calculated. Of 8,279 homes, 401 families (2,065 people) were monitored; 141 ILI cases were identified, yielding an incidence of 6.8% (95% CI 5.5-7.6), 56% of cases sought medical attention, mostly (80%) in public health services. Among the ILIs, 84% of nasopharyngeal swabs were tested, 22% positive for respiratory viruses; 86% FLU (63% FLU A, 37% FLU B). An association (p<0.001) between ILI disease and aged less than 5 years (RR: 2.43 (1.68-3.49) was found. This is the first study that gives information on Influenza burden in Paraguay. Telephone monitoring was a good strategy for house monitoring in order to identify cases of ILI. Influenza virus was the most common pathogen identified, with a high demand for medical assistance, which results in a substantial burden for health services.

Pandemia por influenza A H1N1 2009: características clínicas y epidemiológicas de los casos pediátricos en Paraguay / The 2009 H1N1 influenza A pandemic: clinical and epidemiological characteristics of pediatric cases in Paraguay

Objetivo: Describir las características clínicas y epidemiológicas de los casos pediátricos (0 a 18 años) reportados a la Dirección General de Vigilancia de la Salud (DGVS) durante la pandemia del 2009. Metodología: El estudio es observacional, descriptivo con componentes analíticos, incluyéndose todos los casos sospechosos de infección por Influenza A (H1N1) menores de 19 años que fueron notificados a la DGVS a partir del 28 de abril de 2009 hasta el 30 de enero del 2010.Los centros notificadores fueron públicos y privados. Para la recolección de los datos se utilizó una ficha clínico- epidemiológica que incluía: edad, sexo, procedencia, signos y síntomas, co-morbilidades, antecedentes de vacunación, resultado laboratorial para influenza A (H1N1) y evolución clínica. Resultados: Fueron notificados a la DGVS, 3233 casos sospechosos de Influenza A (H1N1), de los cuales el 50,6% era del sexo masculino. El grupo etareo predominante fue de 15 a 18 años (43,9%), seguido del grupo de 1 a 4 años (31,7%). La mayoría de los casos provenía del Departamento Central 38,4%, seguido de Asunción 23%, y Alto Paraná 10,2%. El 90% de los casos se reportó entre junio y agosto. Entre los signos y síntomas más frecuentemente hallados se encuentran la tos (90%), fiebre (77%) y dolor de garganta (61%). El 4,7% de los casos tenía por lo menos un factor de riesgo de complicaciones, citándose entre las más frecuentes el asma (n=91), embarazo (n=26), enfermedad cardiovascular (n=19). El 6,6% de los que presentaron algún factor de riesgo de co-morbilidad, falleció. La tasa de mortalidad fue de 1,6% y fue significativamente mayor en los menores de 1 año (5,6%, p<0,001). En 476 casos (14,7%), se confirmó la infección por Influenza A (H1N1). Conclusión: Las características clínicas observadas fueron similares a las reportadas a nivel internacional. La necesidad de hospitalización y la mortalidad fueron significativamente mayores en los menores de 1 año.

Introduction: In April 2009 the first cases were reported of a new influenza subtype, H1N1 Influenza A, which showed different clinical behavior in different age groups. Objective: To describe the clinical and epidemiological characteristics of pediatric cases (ages 0 to 18 years) reported to the general directorate for health surveillance (DGVS) during the pandemic of 2009.Methodology: The study was observational and descriptive with analytical components, and included all suspected cases of infection by H1N1 influenza A in patients under age 19 reported to the DGVS between April 28, 2009 and January 30, 2010. Reporting centers included both public and private facilities. To collect data we used a clinical-epidemiological form that included: age, sex, place of origin, signs and symptoms, comorbidities, vaccination history, laboratory results for influenza A H1N1, and clinical outcome. Results: The DGVS received 3233 reports of suspected cases of influenza A H1N1, of which 50.6% were in male patients. Incidence was highest in the age 15 to 18 group (43.9%), followed by the age 1 to 4 group (31.7%). Most cases came from the Central Department (38.4%), followed by Asuncion(23%) and Alto Parana 10.2%). Fully 90% of cases were reported between June and August. Signs and symptoms most frequently found were cough (90%), fever (77%) and sore throat (61%). At least one risk factor for complications was present in 4.7% of cases, with the most common being asthma (n=91), pregnancy (n=26), and cardiovascular disease (n=19). Of those that presented any comorbidity risk factor, 6.6% died. The mortality rate was 1.6% and was significantly higher in children under age 1 year (5.6%, p<0.001). In 476 cases (14.7%) infection by H1N1 influenza A was confirmed. Conclusion: The clinical features observed were similar to those reported internationally. The need for hospitalization and mortality were significantly higher in children under age 1 year.

Medicos durante la guerra contra triple alianza 1865-1870 / Physicians during Triple Alliance War 1865-1870 against

Son pocos los datos que se disponen con respecto a la Sanidad Militar que actuó en la guerra contra la triple alianza,algunos de ellos son que el cuerpo médico disponia de un cirujano mayor,tres medicos de primera clase,un farmaceutico(casi todos los extranjeros)y numerosos practicantes paraguayos.Los elementos de curación eran escasos pero la higiene implantado en el ejercito era muy rigurosa,consiguiendose gracias a esto,un estado sanitario relativamente buenolos hospitales de sangre eran improvisados en los campamentos de transpote de heridos y enfermos se realizaban en carretas