Descripción del brote de poliomielitis en la Argentina de 1971 / Description of the 1971 poliomyelitis outbreak in Argentina

La poliomielitis es una enfermedad de antigua data que afecta exclusivamente a los humanos. Sus secuelas de parálisis se encuentran ya documentadas en escritos del antiguo Egipto. Es producida por el poliovirus y se transmite por vía fecal-oral. Uno de cada doscientos niños infectados sufre un ataque vírico a las neuronas motoras del sistema nervioso central, que deja como secuela una parálisis flácida muscular. En la Argentina, las últimas epidemias de poliomielitis ocurrieron entre 1955 y1957, en 1971 y en 1983. La epidemia de 1953 registró 2.700 casos, mientras que en la de 1956 hubo 6.490 casos, con una tasa de mortalidad del 33,7%. Durante 1971, 46 pacientes fueron internados con diagnóstico de poliomielitis en las salas que dependían de la cátedra de Enfermedades Infecciosas de la Facultad de Ciencias Médicas de la Universidad de Buenos Aires, en el predio del Hospital Francisco Javier Muñiz. La cohorte estaba compuesta por 26 varones y 20 mujeres. Hemos realizado una revisión de las historias clínicas de aquellos pacientes, obrantes en el archivo de la cátedra. (AU)

Poliomyelitis is a human disease of ancient origin. Evidence of sequelae of paralysis is documented in ancient Egyptian writings. It is caused by the poliovirus and is transmitted through the fecal-oral route. One out of 200 infected children suffers a viral attack on the central nervous system´s motor neurons, which results in flaccid muscle paralysis. In Argentina, the last polio epidemics occurred between 1955 and 1957, in 1971 and in 1983. The 1953 poliomyelitis epidemic reported a total of 2,700 cases, while in the 1956 outbreak 6,490 cases were recorded with a mortality rate of 33.7%. In 1971, 46 patients were diagnosed with poliomyelitis and admitted to the wards of the Department of Infectious Diseases at the Faculty of Medical Sciences, University of Buenos Aires, located in the Javier Muñiz Hospital. The cohort consisted of 26 men and 20 women. We reviewed the medical records of those patients, recorded in the Department´s archive. (AU)

Efficacy of current vaccines against recently isolated foot and mouth disease virus type A South America (Venezuela) in Egypt 2022

Foot and mouth disease is a highly contagious viral disease that poses a significant economic threat to cloven-hoofed animals, including cattle and sheep. The emergence of a novel foot and mouth disease virus-A isolate, FMDV-A-Egy-AHRI-RL385-Ven-2022, in Egypt in 2022 has raised concerns about its potential impact on existing vaccination programs. Given that vaccination is a key strategy for foot and mouth disease virus control, the present study was aimed to assess the cross-protective efficacy of both local and imported inactivated vaccines against this new threat. Through challenge experiments and serum neutralization tests, we observed limited effectiveness of both vaccine types. The calculated r1-values at 28 days post-vaccination indicated a minimal immune response to FMDV-A-Egy-AHRI-RL385-Ven-2022 (0.176 and 0.175 for local and imported vaccines, respectively). Challenge experiments further confirmed these findings, revealing 0percent protection from the local vaccine and only 20percent rotection from imported vaccines by day 7 post-challenge. These results underscore the urgent need to update existing foot and mouth disease virus vaccines in Egypt by incorporating the newly circulating FMDV-A-Egy-AHRI-RL385-Ven-2022 strain. This proactive measure is crucial to prevent future outbreaks and ensure effective disease control(AU)

La fiebre aftosa es una enfermedad vírica muy contagiosa que supone una importante amenaza económica para los animales biungulados, entre ellos el ganado vacuno y ovino. La aparición de un nuevo aislado del virus A de la fiebre aftosa, el FMDV-A-Egy-AHRI-RL385-Ven-2022, en Egipto en 2022 ha suscitado preocupación por su posible impacto en los programas de vacunación existentes. Dado que la vacunación es una estrategia clave para el control del virus de la fiebre aftosa, el objetivo del presente estudio fue evaluar la eficacia protectora cruzada de las vacunas inactivadas locales e importadas frente a esta nueva amenaza. Mediante experimentos de desafío y pruebas de seroneutralización, observamos una eficacia limitada de ambos tipos de vacuna. Los valores r1 calculados a los 28 días posvacunación indicaron una respuesta inmunitaria mínima frente a FMDV-A-Egy-AHRI-RL385-Ven-2022 (0,176 y 0,175 para las vacunas local e importada, respectivamente). Los experimentos de provocación confirmaron aún más estos resultados, revelando un 0 por ciento de protección de la vacuna local y sólo un 20 por ciento de protección de las vacunas importadas al séptimo día después de la provocación. Estos resultados subrayan la urgente necesidad de actualizar las vacunas existentes contra el virus de la fiebre aftosa en Egipto incorporando la nueva cepa circulante FMDV-A-Egy-AHRI-RL385-Ven-2022. Esta medida proactiva es crucial para prevenir futuros brotes y garantizar un control eficaz de la enfermedad(AU)

Big data analytics for integrated infectious disease surveillance in sub-Saharan Africa

Background: Infectious disease outbreaks are common in sub-Saharan Africa (SSA). Consequently, integrated public health surveillance has become increasingly essential for the region. Health surveillance systems enable early detection and monitoring of emerging and re-emerging disease outbreaks, thus informing preparedness and response measures. However, complex and intertwined factors obstruct a successful integrated public health surveillance in SSA, with dire consequences. Objectives: The objective of this article was to establish how big data analytics can be used to enhance integrated infectious disease surveillance and response in SSA. Method: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used to identify and select relevant articles. A total of 10 studies that addressed the article's objective were selected. Results: Findings reveal several barriers to the application of big data analytics for public health surveillance in SSA. These include the absence of regulatory and data governance frameworks for big data management in healthcare, disparities in digital health infrastructure across SSA's healthcare systems, and the digital and analytical skills required for data capture and interpretation. The development of regulatory frameworks is essential for the ethical application of analytical technologies such as artificial intelligence. Conclusion: This article's contributions emphasise the need for comprehensive strategies for the application of big data analytics for public health surveillance, as well as addressing barriers to its successful application by highlighting the requirements for an integrated infectious disease surveillance and response system in SSA. Contribution: The article contributes to the body of knowledge on the interplay between the public health space and digital health interventions by emphasising the beneficial applications of big data analytics for surveillance and response to address emerging and re-emerging infectious disease outbreaks in the health systems of sub-Saharan Africa.

Asociación entre las tendencias de búsqueda en internet con el número de casos confirmados por la viruela símica: estudio multinacional en diez países / Association between internet search trends and the number of confirmed monkeypox cases: a multinational study in ten countries

INTRODUCCIÓN: La viruela símica es una infección zoonótica que se ha distribuido por todo el mundo. La búsqueda de información en internet refleja el interés y concientización de la población acerca de salud. OBJETIVO: Determinar la asociación entre el volumen relativo de búsquedas en internet con el número de casos confirmados por la viruela símica en diez países. MÉTODOS: Se realizó un estudio obser- vacional, analítico, retrospectivo, utilizando la herramienta Google Trends (GT™) para encontrar el volumen relativo búsqueda (VRB) sobre viruela símica desde 01 de enero al 31 de agosto del 2022 usando términos de búsqueda en el idioma oficial de los 10 países con mayor número de casos en dichas fechas, registrado por Our World in Data. Para establecer la relación lineal entre el VRB con los nuevos de casos por día se usó el coeficiente de correlación de Pearson con un nivel de significancia (p ≤ 0,05). RESULTADOS: Se encontró un coeficiente de correlación de Pearson fuerte en Brasil (Rp = 0,562,p = 0,001), y débil en países como Alemania (Rp = 0,281, p = 0,004), Estados Unidos de Norteamérica (Rp = 0,255, p = 0,008), España (Rp = 0,122, p = 0,213), Perú (Rp = 0,120, p = 0,333), Canadá (Rp = 0,116, p = 0,238), Francia (Rp = 0,095, p = 0,335), Reino Unido (Rp = 0,085, p = 0,362), Portugal (Rp = 0,024, p = 0,805) y Países Bajos (Rp = 0,067, p = 0,497). CONCLUSIÓN: Nuestro estudio evidencio que el VRB presento una relación positiva con el número de nuevos casos de viruela símica. Asimismo, se observo un coeficiente de correlación fuerte en Brasil, y en el resto de países fue débil.

BACKGROUND: Smallpox is a zoonotic infection that has been distributed worldwide. The search for information on the Internet reflects the interest and awareness of the population about health. AIM: To determine the correlation between the relative volume of internet searches and the number of confirmed cases of smallpox in ten countries. METHODS: An observational, analytical, retrospective study was conducted using the Google Trends (GT™) tool to find the relative search volume (RSV) on monkeypox from January 1 to August 31, 2022 using search terms in the official language of the 10 countries with the highest number of cases on those dates, as recorded by Our World in Data. To establish the relationship between RSV and new cases per day, Spearman's correlation was used with a significance level (p ≤ 0.05). RESULTS: A. strong Pearson correlation coefficient was found in Brazil (Rp = 0.562, p = 0.001), and weak in countries like Germany (Rp = 0.281, p = 0.004), United States (Rp = 0.255, p = 0.008), Spain (Rp = 0. 122, p = 0.213), Peru (Rp = 0.120, p = 0.333), Canada (Rp = 0.116, p = 0.238), France (Rp = 0.095, p = 0.335), United Kingdom (Rp = 0.085, p = 0.362), Portugal (Rp = 0.024, p = 0.805) and Netherlands (Rp = 0.067, p = 0.497). CONCLUSION: Our study showed that RSV had a positive relationship with the number of new cases of smallpox. Also, a strong correlation coefficient was observed in Brazil, while the rest of the countries showed a weak correlation coefficient.

Las epidemias de viruela y la introducción de la vacuna en el Virreinato del Río de la Plata / Smallpox epidemics and vaccine introduction in the Viceroyalty of the Río de la Plata

La viruela fue una de las enfermedades epidémicas más temidas desde la antigüedad debido a su alta mortalidad y a las secuelas que dejaba en aquellos que lograban sobrevivir. En el presente trabajo se abordará el ingreso de esta enfermedad en nuestro continente, así como su manifestación a través de epidemias, brotes y focos endémicos. Al mismo tiempo se verá qué reacciones provocó dentro del ámbito médico durante los años del Virreinato del Río de la Plata. Se analizarán los problemas que surgieron con el uso de la vacuna importada, así como el hallazgo de nuestra vacuna local, finalizando con los comienzos de la organización de los servicios de vacunación obligatoria. (AU)

Smallpox was one of the most feared epidemic diseases since ancient times due to its high mortality and the sequelae caused in those that managed to survive. In the present work, the introduction of this disease into our continent will be addressed as well as its manifestation through epidemics, outbreaks, and endemic foci. At the same time, the reactions this disease caused inside the medical field during the years of the Viceroyalty of the Río de la Plata will be observed. The problems that arose from the usage of the imported vaccine and the discovery of our local vaccine will be analyzed, and it will finish with the beginnings of the organization of the mandatory vaccination services. (AU)

Brote de tinea capitis y otras micosis superficiales en una comunidad urbana de Medellín / Tinea capitis outbreak and other superficial mycosis in an urban community of Medellín

Introducción. Las dermatofitosis son infecciones fúngicas superficiales de epitelios queratinizados. La tinea capitis es una de ellas y afecta a poblaciones escolares vulnerables. Carpinelo es un barrio del área periférica de Medellín con precarias condiciones socioeconómicas. Ante la sospecha de un brote de dermatofitosis, los afectados fueron evaluados. Objetivo. Evaluar clínica y microbiológicamente pacientes del barrio Carpinelo con sospecha de micosis cutáneas para determinar la presencia de un brote por dermatofitos. Materiales y métodos. Se llevó a cabo un estudio descriptivo, de corte longitudinal, con muestreo a conveniencia. Se hizo una búsqueda activa de casos en el Jardín Educativo Buen Comienzo de Carpinelo en niños de la institución y sus familiares. Se evaluaron clínicamente y se tomaron muestras de escamas y cabellos para exámenes directos y cultivos microbiológicos. Se analizó el perfil demográfico, clínico y micológico, con el programa estadístico SPSS™, versión 25. Resultados. Se estudiaron 57 pacientes, 47 eran menores de edad con una media de edad de seis años; se observó una proporción de hombres y mujeres de 2:1. Los pacientes con resultados positivos se diagnosticaron con tinea capitis (78,95 %), tinea faciei (15,79 %) y tinea corporis (10,52 %). El 75,43 % de los pacientes recibió tratamiento previo y de estos el 69,73 % fue con esteroides. El examen directo fue positivo en el 53,84 % y los cultivos en el 46,5 % de los casos. Los agentes aislados fueron: Microsporum canis (77,77 %), Trichophyton spp. (11,11 %), Trichophyton rubrum (5,55 %) y Malassezia spp. (5,55 %). Conclusión. Tinea capitis fue la presentación clínica más común y M. canis el dermatofito más frecuentemente aislado. Llamó la atención el uso de esteroides como primera y única opción del tratamiento empírico' lo cual resalta la importancia del diagnóstico microbiológico para proporcionar la terapia apropiada.

Introduction. Dermatophytoses are superficial fungal infections of the keratinized epithelium like tinea capitis. The latte mainly affects school-vulnerable populations. Carpinelo is a peripheral neighborhood in Medellín with poor socioeconomic conditions and where a suspected tinea capitis outbreak took place. Objective. To study and characterize, clinically and microbiologically, patients with suspected dermatophytosis in Carpinelo. Materials and methods. We carried out a descriptive and longitudinal study with an active case search of tinea capitis in children and their relatives from the Jardín Educativo Buen Comienzo community in Carpinelo. Patients were clinically evaluated, and samples of scales and hair were taken to perform mycological studies with a 10 % potassium hydroxide and culture in Sabouraud and Mycosel agar. We analyzed the data with the statistical program SPSS™. 25 version. Results. Fifty-seven individuals were studied: 47 were children with a mean age of six years and a ratio of 2:1 male to female. Patients with confirmed diagnosis presented the following clinical forms: tinea capitis (78.95%), tinea faciei (15.79%) or tinea corporis (10.52%). Out of the total, 69.76% of the patients had previous treatment with steroids. The direct test was positive in 53.84% of the samples, and 46.15% had positive cultures. The isolated species were: Microsporum canis (77.77%), Trichophyton spp. (11.11%), Trichophyton rubrum (5.55%), and Malassezia spp. (5.55 %). Conclusion.Tinea capitis was the most common clinical form, and M. canis was the most frequently isolated species. The use of steroids as the first and only option for empiric treatment was worth of notice. The findings of this study point out the importance of microbiological diagnosis in choosing the best treatment for the patients.

Enfermedad invasiva por Haemophilus influenzae: reporte de 14 casos luego de un año de iniciada la pandemia por COVID-19 / Invasive Haemophilus influenzae disease: A report of 14 cases one year after the COVID-19 pandemic outbreak

El Haemophilus influenzae (Hi) causa enfermedad invasiva (EI). Se distinguen cepas capsuladas, como el serotipo b (Hib), y cepas no tipificables (HNT). Al año de declarada la pandemia por COVID-19, observamos un aumento de casos. Se describen las características clínico-epidemiológicas de niños con EI por Hi internados en el hospital (julio 2021-julio 2022). Hubo 14 casos; 12 previamente sanos. Aislamientos: Hib (n = 6), Hi serotipo a (n = 2), HNT (n = 5), 1 no se tipificó. Mediana de edad: 8,5 meses (RIC 4-21). Manifestaciones: meningitis (n = 5), neumonía (n = 6), celulitis (n = 2), artritis (n = 1). Nueve presentaron vacunación incompleta para Hib. Observamos un incremento de EI por Hi de 2,5 veces respecto a años previos. Estos datos sugieren el resurgimiento de Hib por la caída de las coberturas de vacunación y porque otras cepas de Hi no b están en aumento.

Haemophilus influenzae (Hi) causes invasive disease. There are encapsulated strains, such as serotype b (Hib), and non-typeable strains (NTHi). One year after the outbreak of the COVID-19 pandemic, the number of cases increased. In this report we describe the clinical and epidemiological characteristics of children hospitalized with invasive Hi disease (July 2021-July 2022). There were 14 cases; 12 were previously healthy children. Isolations: Hib (n = 6), Hi serotype a (n = 2), NTHi (n = 5); 1 case was not typified. Median age: 8.5 months (IQR: 4­21). Manifestations: meningitis (n = 5), pneumonia (n = 6), cellulitis (n = 2), arthritis (n = 1). Incomplete Hib immunization was observed in 9 children. Invasive Hi disease increased 2.5 times from previous years. These data suggest the reemergence of Hib due to a decline in vaccination coverage and an increase in other non-b-type Hi serotypes.

Carga de enfermedad en el Perú. Estimación de los años de vida saludables perdidos 2019 / Burden of disease in Peru. Estimated healthy years of life lost 2019

En ese sentido, el estudio de carga de enfermedad en el Perú del 2019 nos presenta las principales enfermedades y lesiones que han aportado mayor número de años de vida saludables perdidos en el país, reconociendo no solo aquellas que producen muerte prematura, sino también discapacidad. De esta manera, podemos disponer de información valiosa para la toma de decisiones en salud pública y dirigir las acciones hacia un mayor beneficio para la población de nuestro país. Los años de vida ajustados por discapacidad -AVISA- estiman la carga de la enfermedad, de acuerdo a las distintas causas o problemas de salud consideradas. Un AVISA corresponde a un año de vida sana perdido y la medición de la carga de enfermedad por este indicador significaría la brecha existente entre la situación actual de salud de una población y la ideal en la que cada miembro de esa población podría alcanzar la vejez libre de enfermedad y discapacidad.

Outbreak report of SARS-CoV-2 infection by airborne transmission: Epidemiologic and molecular evidence / Reporte de un brote de infección por SARS-CoV-2 por transmisión aérea: evidencia epidemiológica y molecular

Introduction: It has been shown that the transmission of SARS-CoV-2 occurs mainly by air, and the risk of infection is greater in closed spaces. Objective: To describe the epidemiology, virology and molecular characterization of a COVID-19 outbreak at a closed vaccination point during the third wave of SARS-CoV-2 in Colombia. Materials and methods: Diagnostic tests, interviews, sampling, cell cultures and viral sequencing were carried out, the latter being molecular characterization and lineage identification. Results: Seven workers were positive for SARS-CoV-2; among these, 3 samples were analyzed, plus an additional sample belonging to the mother of the presumed index case; all samples were identified with lineage B.1.625, with a maximum of 2 nucleotides difference between them. Conclusions: Variant B.1.625 was identified as the cause of the COVID-19 outbreak, and a co-worker was also identified as the index case. Unexpectedly, attending a vaccination day became a risk factor for acquiring the infection.

Introducción. Se ha demostrado que la transmisión de SARS-CoV-2 se produce principalmente por vía aérea y el riesgo de infección es mayor en espacios cerrados con alta concentración de personas; este último factor se presentó en algunos de los puestos de vacunación de la ciudad de Medellín. Objetivo. Describir la epidemiología, virología y caracterización molecular de un brote de COVID-19 en un punto de vacunación cerrado durante la tercera ola de SARS-CoV-2 en Colombia. Materiales y métodos. Se realizaron test diagnósticos, entrevistas, toma de muestras, aislamiento viral y secuenciación genómica. Con esta última, se hizo la caracterización molecular y se identificó el linaje. Resultados. Siete trabajadores fueron positivos para SARS-CoV-2, y de estos, tres muestras fueron secuenciadas, más una muestra adicional perteneciente a la madre del presunto caso índice. Todas las muestras fueron identificadas con el linaje B.1.625, con un máximo de dos nucleótidos de diferencia entre ellas. Conclusiones. Se identificó la variante B.1.625 como la causante del brote de COVID-19, y también un compañero de trabajo fue identificado como el caso índice. De forma imprevista, asistir a una jornada de vacunación se convirtió en un factor de riesgo para adquirir la infección.

Prevention and control of COVID-19 outbreak in a hemodialysis center / Prevención y control de un brote de COVID-19 en una unidad de hemodiálisis

BACKGROUND: The prevention and control of SARS-CoV-2 infection in hemodialysis (HD) units is challenging. AIM: To describe the clinical characteristics and outcome of patients with chronic kidney disease (CKD) on HD with COVID-19, between March 2020 and January 28, 2021, attending a single HD unit in Bogotá, Colombia. MATERIAL AND METHODS: In this prospective observational study, incidence, prevalence, and case-fatality rate were estimated, including screening results with RT-PCR and anti-SARS-CoV-2 IgG and IgM antibodies in all patients and health personnel in the HD unit. RESULTS: Among patients and health workers, 55 and 9 cases of COVID-19 were identified, respectively. The median age of patients was 63 years (84% males). Fifty five percent of patients were symptomatic, with fever, cough and/or myalgia. The most common comorbidities were hypertension, type 2 diabetes mellitus, and coronary heart disease. The cumulative incidence of infection was 30.2%, population seroprevalence was 24.9%, and fatality was 9.1%. CONCLUSIONS: The incidence of SARS-CoV-2 infection in this HD unit was high. Strict biosafety protocols are required to prevent outbreaks.

INTRODUCCIÓN: La prevención y el control de la infección por SARS-CoV-2 en las unidades de hemodiálisis (HD) es un desafío. OBJETIVO: Describir las características clínicas y la evolución de los pacientes con enfermedad renal crónica (ERC) en HD con COVID-19, entre marzo de 2020 y el 28 de enero de 2021, que acudieron a una unidad de HD en Bogotá, Colombia. MATERIAL Y MÉTODOS: Estudio observacional prospectivo con estimación de incidencia, prevalencia y letalidad, incluyendo los resultados del cribado con RT-PCR y anticuerpos IgG e IgM anti-SARS-CoV-2 en todos los pacientes y personal sanitario de la unidad de HD. RESULTADOS: Se identificaron 55 casos de pacientes en HD y 9 casos de trabajadores de salud con COVID-19. La mediana de edad de los pacientes fue de 63 años y 84% eran hombres. Cincuenta y cinco por ciento de los pacientes eran sintomáticos, con fiebre, tos y/o mialgia. Las comorbilidades más frecuentes fueron hipertensión arterial, diabetes mellitus tipo 2 y enfermedad coronaria. La incidencia acumulada de infección fue del 30,2%, la seroprevalencia poblacional del 24,9% y la letalidad del 9,1%. CONCLUSIONES: La incidencia de infección por SARS-CoV-2 en esta unidad de HD fue alta. Se requieren de protocolos estrictos de bioseguridad para evitar brotes.

Challenges to global pertussis prevention and control / 中华流行病学杂志

Pertussis is an acute, highly infectious respiratory disease caused by Bordetella pertussis, and is one of the leading causes of infant disease and death worldwide. The pertussis vaccine has been used in the expanded program on immunization globally since 1974 and the vaccination coverage remains high. In recent years, the pertussis incidence rate increased, even pertussis outbreaks occurred, in more and more countries or areas after years with low incidence level. The disease burden of pertussis has been seriously underestimated, and the prevention and control of pertussis is facing many challenges. This article reviews the epidemic status of pertussis worldwide, the factors affecting the reemergence of pertussis, and the challenges in the prevention and control to provide a reference for prevention and control of pertussis.

Epidemiological characteristics and research progress of monkeypox in 2022 / 中华流行病学杂志

Monkeypox is a zoonosis caused by monkeypox virus. Monkeypox was endemic mainly in central and western Africa in the past. Since May 7, 2022, monkeypox outbreaks have been reported in many non-epidemic countries and regions around the world. As of December 25, 2022, monkeypox cases have been detected in 110 countries and areas. Moreover, human to human transmission, especially among men who have sex with men, has aroused high global concern. The incidence, transmission route and clinical characteristics of monkeypox in 2022 seemed different from those in the past. Therefore, this paper summarizes the progress in research of the changes of epidemiological characteristics of monkeypox, the clinical characteristics of monkeypox and its prevention and treatment to provide scientific evidence for the prevention and control of monkeypox.

Epidemiological characteristics of a 2019-nCoV outbreak caused by Omicron variant BF.7 in Shenzhen / 中华流行病学杂志

Objective: To explore the epidemiological characteristic of a COVID-19 outbreak caused by 2019-nCoV Omicron variant BF.7 and other provinces imported in Shenzhen and analyze transmission chains and characteristics. Methods: Field epidemiological survey was conducted to identify the transmission chain, analyze the generation relationship among the cases. The 2019-nCoV nucleic acid positive samples were used for gene sequencing. Results: From 8 to 23 October, 2022, a total of 196 cases of COVID-19 were reported in Shenzhen, all the cases had epidemiological links. In the cases, 100 were men and 96 were women, with a median of age, M (Q1, Q3) was 33(25, 46) years. The outbreak was caused by traverlers initial cases infected with 2019-nCoV who returned to Shenzhen after traveling outside of Guangdong Province.There were four transmission chains, including the transmission in place of residence and neighbourhood, affecting 8 persons, transmission in social activity in the evening on 7 October, affecting 65 persons, transmission in work place on 8 October, affecting 48 persons, and transmission in a building near the work place, affecting 74 persons. The median of the incubation period of the infection, M (Q1, Q3) was 1.44 (1.11, 2.17) days. The incubation period of indoor exposure less than that of the outdoor exposure, M (Q1, Q3) was 1.38 (1.06, 1.84) and 1.95 (1.22, 2.99) days, respcetively (Wald χ2=10.27, P=0.001). With the increase of case generation, the number and probability of gene mutation increased. In the same transmission chain, the proportion of having 1-3 mutation sites was high in the cases in the first generation. Conclusions: The transmission chains were clear in this epidemic. The incubation period of Omicron variant BF.7 infection was shorter, the transmission speed was faster, and the gene mutation rate was higher. It is necessary to conduct prompt response and strict disease control when epidemic occurs.

Analysis on infection sources and transmission chains of three outbreaks caused by 2019-nCoV Omicron variant in Beijing, China / 中华流行病学杂志

Objective: To investigate the infection sources and the transmission chains of three outbreaks caused by 2019-nCoV Omicron variant possibly spread through cross-border logistics in Beijing. Methods: Epidemiological investigation and big data were used to identify the exposure points of the cases. Close contacts were traced from the exposure points, and the cases' and environmental samples were collected for nucleic acid tests. Positive samples were analyzed by gene sequencing. Results: The Omicron variant causing 3 outbreaks in Beijing from January to April, 2022 belonged to BA.1, BA.1.1 and BA.2. The outbreaks lasted for 8, 12 and 8 days respectively, and 6, 42 and 32 cases infected with 2019-nCoV were reported respectively. International mail might be the infection source for 1 outbreak, and imported clothes might be the infection sources for another 2 outbreaks. The interval between the shipment start time of the imported goods and the infection time of the index case was 3-4 days. The mean incubation period (Q1, Q3) was 3 (2,4) days and the mean serial interval (Q1, Q3) was 3 (2,4)days. Conclusions: The 3 outbreaks highlighted the risk of infection by Omicron variant from international logistics-related imported goods at normal temperature. Omicron variant has stronger transmissibility, indicating that rapid epidemiological investigation and strict management are needed.

Epidemiological characteristics of norovirus acute gastroenteritis outbreaks and influencing factors in China, 2007-2021 / 中华流行病学杂志

Objective: To analyze the epidemiological characteristics of norovirus-caused acute gastroenteritis outbreaks in China, identify the factors influencing the scale of outbreaks, and provide scientific evidences for early control of norovirus infection outbreaks. Methods: The descriptive epidemiological analysis approach was applied to analyze the incidence of national norovirus infection outbreaks by using the data from the Public Health Emergency Event Surveillance System in China from January 1, 2007 to December 31, 2021. The unconditional logistic regression model was applied to analyze the risk factors that affected the outbreaks' scale. Results: A total of 1 725 norovirus infection outbreaks were recorded in China from 2007 to 2021, with an upward trend in the number of the reported outbreaks. The southern provinces had their annual outbreak peaks from October to March; the northern provinces had two outbreak peaks from October to December and from March to June annually. The outbreaks occurred mainly in southeastern coastal provinces with a trend of gradual spread to central, northeastern and western provinces. The outbreaks mainly occurred in schools and childcare setting (1 539 cases, 89.22%), followed by enterprises and institutions (67 cases, 3.88%) and community households (55 cases, 3.19%). Human to human transmission was the main infection route (73.16%), and norovirus GⅡ genotype was the predominate pathogen causing the outbreaks (899 cases, 81.58%). The time interval between the onset of the primary case and the outbreak reporting M (Q1, Q3) was 3 (2, 6) days and the case number of the outbreak M (Q1, Q3) was 38 (28, 62). The timeliness of outbreak reporting was improved in recent years and the scale of the outbreaks showed a decreasing trend over the years, the differences in reporting timeliness and outbreak scale among different settings were significant (P<0.001). The factors that affected outbreaks' scale included the outbreak setting, transmission route, outbreak reporting timeliness and type of living areas (P<0.05). Conclusions: From 2007 to 2021, the number of the norovirus-caused acute gastroenteritis outbreaks increased in China and the more areas were affected. However, the outbreak scale showed a decreasing trend and the outbreak reporting timeliness was improved. It is important to further improve the surveillance sensitivity and reporting timeliness for the effective control of the outbreak scale.

Thinking about development of multi-channel surveillance and multi-dimensional early warning system of emerging respiratory communicable diseases / 中华流行病学杂志

The world has paid a heavy price for the pandemic of the emerging respiratory communicable disease, so more concern about communicable disease surveillance and early warning has been aroused. This paper briefly reviews the establishment of the surveillance and early warning system of respiratory communicable diseases in China, discusses its future development and introduces the novel surveillance methods and early warning models for the purpose of establishment of a multi-channel surveillance and multi-dimensional early warning system of communicable diseases in the future and the improvement of the prevention and control of emerging respiratory communicable diseases in China.

Epidemiological characteristics and serum antibody detection of a COVID-19 aggregated outbreak in vaccinated population / 中华预防医学杂志

An epidemiological investigation was conducted on a cluster epidemic of COVID-19 in the vaccinated population in Beijing in 2022, and serum samples were collected from 21 infected cases and 61 close contacts (including 20 cases with positive nucleic acid in the isolation observation period). The results of antibody detection showed that the IgM antibody of two infected persons was positive, and the IgG antibody positive rates of patients who were converted, not converted to positive and infected persons were 36.84% (7/19), 63.41% (26/41) and 71.43% (15/21), respectively. About 98.78% of patients had been vaccinated with the SARS-CoV-2 inactivated vaccine. The positive rate of IgG antibody in patients immunized with three doses of vaccine was 86.00% (43/50), which was higher than that in patients with one or two doses [16.12% (5/31)]. The antibody level of M (Q1, Q3) in patients immunized with three doses was 4.255 (2.303, 7.0375), which was higher than that in patients with one or two doses [0.500 (0.500, 0.500)] (all P values<0.001). The antibody level of patients who were vaccinated less than three months [7.335 (1.909, 7.858)] was higher than that of patients vaccinated more than three months after the last vaccination [2.125 (0.500, 4.418)] (P=0.007). The positive rate and level of IgG antibody in patients who were converted to positive after three doses were 77.78% (7/9) and 4.207 (2.216, 7.099), respectively, which were higher than those in patients who were converted after one or two doses [0 and 0.500 (0.500, 0.500)] (all P values<0.05).

Diagnosis and treatment of adult tumor patients with COVID-19 / 中华肿瘤杂志

After the first outbreak of corona virus disease 2019 (COVID-19) at the end of 2019, it has caused multiple rounds of transmission in many countries around the world. Cancer patients are mainly elderly people, and the immunosuppression state caused by the tumor itself and anti-tumor treatment, more accompanying underlying diseases, and more hospital environmental exposure leading to a higher incidence of COVID-19 infection. The proportion of severe cases after infection is high, and the mortality is high. Therefore, based on the domestic and foreign research and clinical practice, the Expert Committee of Geriatric Cancer Prevention and Treatment of Chinese Society of Clinical Oncology launched a discussion based on the characteristics of cancer patients, including the epidemiology, clinical manifestations, differential diagnosis, definition and risk factors of severe cases, diagnosis and treatment recommendations, recovery of anti-tumor treatment and vaccination recommendations. To provide the corresponding suggestions for the clinical diagnosis and treatment of such patients.