Near real-time surveillance of the SARS-CoV-2 epidemic with incomplete data.

Designing public health responses to outbreaks requires close monitoring of population-level health indicators in real-time. Thus, an accurate estimation of the epidemic curve is critical. We propose an approach to reconstruct epidemic curves in near real time. We apply this approach to characterize the early SARS-CoV-2 outbreak in two Spanish regions between March and April 2020. We address two data collection problems that affected the reliability of the available real-time epidemiological data, namely, the frequent missing information documenting when a patient first experienced symptoms, and the frequent retrospective revision of historical information (including right censoring). This is done by using a novel back-calculating procedure based on imputing patients' dates of symptom onset from reported cases, according to a dynamically-estimated "backward" reporting delay conditional distribution, and adjusting for right censoring using an existing package, NobBS , to estimate in real time (nowcast) cases by date of symptom onset. This process allows us to obtain an approximation of the time-varying reproduction number ( R t ) in real-time. At each step, we evaluate how different assumptions affect the recovered epidemiological events and compare the proposed approach to the alternative procedure of merely using curves of case counts, by report day, to characterize the time-evolution of the outbreak. Finally, we assess how these real-time estimates compare with subsequently documented epidemiological information that is considered more reliable and complete that became available later in time. Our approach may help improve accuracy, quantify uncertainty, and evaluate frequently unstated assumptions when recovering the epidemic curves from limited data obtained from public health surveillance systems in other locations.

Effect of mobile phone text messaging for improving the uptake of influenza vaccination in patients with rare diseases.

OBJECTIVES: Influenza vaccine is recommended in some chronic medical conditions, including several rare diseases. The objectives of the study were to assess the effect of text message reminders on influenza vaccination uptake of patients with selected rare diseases and delayed vaccination, and to describe their characteristics. METHODS: Quasi-experimental pre-post intervention study performed along the 2016 influenza vaccination campaign in the Autonomous Community of Madrid. Unvaccinated patients diagnosed with a selected rare disease were targeted for intervention. SMS were sent to them at least one month after the beginning of the campaign, in four consecutive weeks. Those with no mobile phones available or no certainty of message reception, were assigned as controls. The association between the reception of the SMS and vaccination uptake was assessed using multiple poisson regression models. RESULTS: Of 69.040 patients with delayed vaccination, 87.2% received an SMS reminder in the asigned contact mobile telephone. Global influenza vaccine coverage reached 41.3%. The uptake of influenza vaccine was significantly higher among those receiving the reminder (9.3% vs. 7.1% in the control group, p < 0.001). Those who received a SMS reminder were 30% more likely to uptake seasonal influenza vaccine. By sex and age, the reception of the reminder was associated with a significantly higher probability of vaccination in men ≥65 years with at least a concurrent chronic condition (IRR: 1.58, CI95%: 1.25-2.00). Among women, this higher probability was detected in those between 14 and 64 years of age (IRR: 1.41, CI95%: 1.22-1.63), and ≥65 years without concurrent chronic conditions (IRR: 1.40, CI95%: 1.05-1.89). CONCLUSION: Although the intervention was modestly effective, it proved beneficial in some cases. It can be an additional strategy to improve vaccine uptake, since it is simple, feasible, affordable and easily scalable, particularly when immunization and target population data are available in population registries.

Age and gender differences in Clostridium difficile-related hospitalization trends in Madrid (Spain) over a 12-year period.

This study aimed to analyze temporal trends by gender and age in Clostridium difficile infection (CDI)-related hospitalization rates in the Autonomous Community of Madrid (Spain) over a 12-year period. A population-based cross-sectional study of all hospital admissions with a CDI diagnosis from 2003 to 2014 was carried out. Annual age-specific hospitalization rates were calculated by gender. All the analyses were performed separately for total hospitalizations and hospitalizations with CDI as the primary diagnosis. Joinpoint regression models were used to analyze time trends. A total of 13,526 hospital discharges were identified (26.8 % with CDI as the primary diagnosis). In both sexes, a gradient in age-specific rates was observed, ranging in 2014 from 5.92 hospitalizations per 100,000 person-years in patients <15 years of age to 378.96 in patients ≥85 years of age. Since 2009, in the age group of 15-44 years, both men and women presented an increasing trend of around 18 %. A significantly increasing trend was detected in women of age 45-84 years, with an estimated annual percentage of change of 7.6 % in the age group of 45-64 years, and rounding with 4.5 % in the age group of 65-84 years. In men of age 45-64 years, the average annual percentage of increase was 4.7 %, and it was 21.1 % between 2010 and 2014 in the age group of 65-74 years. No trends were identified in the 85 years and over age group. Surveillance methods to assess trends by age group should be implemented. Preventive and therapeutic initiatives should remain a priority.

Coverage of and factors associated with pneumococcal vaccination in chronic obstructive pulmonary disease.

SETTING: Patients aged ⩾ 40 years with a diagnosis of chronic obstructive pulmonary disease (COPD; codes R95, R79 and R91 in the International Classification for Primary Care) registered in primary care clinical records in the Autonomous Community of Madrid, Spain. OBJECTIVE: To assess pneumococcal vaccination coverage in patients with COPD and to analyse factors associated with vaccination uptake. DESIGN: Population-based cross-sectional study in which data were collected in September 2010. RESULTS: We found that 93,797 patients (72.0% men and 28.0% women) had COPD. Overall coverage was 65.5% (67.5% men vs. 60.4% women, P < 0.001). In patients aged 40-59 years, coverage was 19.5%, reaching 75.8% in those aged ⩾ 60 years. In patients aged <60 years, uptake was associated with a higher number of comorbidities and appropriate adherence to seasonal influenza and pandemic vaccination schedules. In patients aged ⩾ 60 years, factors associated with uptake in both sexes were older age and appropriate adherence to seasonal influenza vaccination schedules. Factors associated with uptake in men were concomitant comorbidities and pandemic vaccination. CONCLUSION: Vaccination coverage in individuals aged <60 years with COPD is less than acceptable in Madrid. Coverage was higher in men and in patients with another chronic condition.

Temporal trends in incidence rates of herpes zoster among patients treated in primary care centers in Madrid (Spain), 2005-2012.

OBJECTIVES: This study aimed to estimate total and age-specific incidence rates of HZ with data from electronic clinical records in primary care (ECRPC) and to analyze trends by sex and age. METHODS: Descriptive cross-sectional study covering the incident HZ episodes registered in the ECRPC of the Madrid Regional Public Health System in 2005-2012. Annual crude and age-adjusted incidence rates were calculated. Differences by sex and age were assessed by poisson regression. The annual percentage of change (APC) of incidence rates and 'breakthrough points' of the time trends were determined with the Joinpoint Regression Program. RESULTS: 211,650 episodes of HZ were identified (60.6% women, 52.2% > 55 years). The incidence rate increased from 363.21 to 481.92 per 100,000 person-year in 2005-2012. Rates were higher among women and increased with age. The APC for the period was 3.59% in men and 3.67% in women (p < 0.05). Age-specific rates increased in patients over 14 years. The APC in the 25-44 age group was 7.4% since 2007. The incidence rate ratio (women/men) was highest in this group. CONCLUSIONS: The incidence of HZ presents an upward trend in 2005-2012 in adults and the elderly. Monitoring the incidence and age-specific rates, will help to detect changes in trends.

Epidemiological usefulness of population-based electronic clinical records in primary care: estimation of the prevalence of chronic diseases.

BACKGROUND: Chronic health problems are the main cause of disease, disability and death in developed countries, and their prevalence is increasing. OBJECTIVE: To estimate the prevalence of selected chronic illnesses based on electronic clinical records in primary care (ECRPC) and to assess its usefulness for epidemiological research, by comparing ECRPC data against those reported by a contemporary health survey. DESIGN: Descriptive cross-sectional study. SETTING: All primary care medical consultations in the Madrid Regional Public Health System (PHS). SUBJECTS: A total of 23 535 182 ECRPC-registered episodes of illness, generated by PHS patients over 15 years of age seeking medical care during 2005-06. MAIN OUTCOME MEASURES: Prevalences of chronic diseases estimated on the basis of medically examined cases registered in ECRPC and morbidity as reported by a contemporary health survey covering the same geographic area. RESULTS: A total of 52.5% of the adult population had some chronic health problem. The highest overall prevalences were hypertension (14.8%), mental disorders (12.0%) and allergy (11.6%). Prevalences were generally highest among women, elderly and the native population. Depending on the specific disease, ECRPC-based prevalences were similar to (e.g. diabetes), higher (e.g. chronic skin problems) or lower (e.g. asthma and dyslipidaemia) than those reported by surveys, with certain age- and sex-related variations. CONCLUSIONS: Prevalences estimated from ECRPC and survey data present variations depending on the disease, age and sex. Both data sources provide complementary information about chronic disease prevalence. ECRPC have the advantage of generating an ongoing standardized register and entailing no additional effort for health professionals.

Papel de la determinación de cotinina en orina en el tratamiento farmacológico del tabaquismo / Role of the measurement of cotinine in urine in the smoking cessation drug treatment

Objetivo: Analizar el factor predictivo de éxito que tiene el estudio de los porcentajes de sustitución de cotinina en orina, obtenidos con parches, en el tratamiento del tabaquismo. Métodos: Un total de 187 fumadores en tratamiento con parches denicotina han sido seguidos durante 12 semanas. A lo largo de este periodo fueron vistos en 8 ocasiones (visita basal, y a la 1, 2, 4, 6, 8, 10 y12 semanas después del día de abandono del tabaco). Antes de instaurar tratamiento se realizaron diversos procedimientos diagnósticos (test de Fagerström, cooximetría y estudio semicuantitativo de cotinina en orina mediante el sistema NicAlert). El análisis semicuantitativo permite conocer esos niveles en una escala comprendida entre 0 y 6.Se utilizaron parches de nicotina de 16 h a diferentes dosis dependiendode los niveles basales de cotinina en orina. El objetivo fundamental del tratamiento fue alcanzar, con los parches de nicotina, los mismos niveles de cotinina en orina que se habían tenido con el consumo de cigarrillos. Las determinaciones de cotinina se realizaron durante las siguientes visitas: basal, y en las de la 1, 2 y 4 semanas después de dejar de fumar. Se definió abstinencia completa como la ausencia total del consumo de cigarrillos desde el día del abandono que se acompañase de niveles de CO en aire espirado iguales o menores de 10 ppm. Resultados: Un total de 187 fumadores han sido incluidos en el estudio.103 mujeres y 84 hombres. Edad media 44,5. Índice abstinencia completa. De los 187 fumadores que comenzaron el estudio, 156 (83%) permanecieron abstinentes a las 4 semanas, 140 (74,8%) a las 8 semanas y 125 (66,8%) a las 12 semanas. Relación entre el índice de abstinencia y la obtención de correctos % de sustitución: a los tres meses de seguimiento en 129 sujetos se habían obtenido correctos porcentajes de sustitución. 106 de los 129 (82,1%) sujetos que obtuvieron adecuados niveles de sustitución cumplieron criterios de abstinencia completa al cabo de las 12 semanas y 23 (17,9%) fracasaron. En tanto que, 19 de los 58 (32,7%) sujetos que no obtuvieron adecuados niveles de sustitución cumplieron criterios de abstinencia completa al cabo de las 12 semanas de seguimiento y 39 (67,3%) fracasaron. Odds ratio 0,17 (0,07-0,33), p menor de 0,0001. Conclusiones: en el tratamiento farmacológico del tabaquismo, la adecuada sustitución nicotínica, se asocia de forma significativa a la probabilidad de cesación. El 70% de los que tienen controlada la cotinina en orina dejan de fumar a las 12 semanas. A nivel global, la fracción prevenible por tener ajustados los niveles de cotinina durante el tratamiento es un 50% superior de éxito comparado con los que no la tienen controlada (AU)

Objective: Analyze the predictive factor of success of the study of the percentages of cotinine replacement in urine, obtained with patches, in the treatment of smoking cessation. Methods: A total of 187 smokers under treatment with nicotine patches were followed-up for 12 weeks. During this period, they were seen on8 occasions (baseline visit, and at 1,2,4,6,8,10 and 12 weeks after the smoking cessation day). Before treatment was initiated, several diagnostic procedures were performed (Fagerström test, Cooximetry and semiquantitative study of cotinine in using the NicAlert system). The semiquantitative analysis makes it possible to know these levels on a scale from 0 to 6.The 16-hour nicotine patches were used at different doses, depending on the baseline levels of cotinine in urine. The fundament objective of treatment was to reach the same levels of cotinine in urine with the nicotine patches that had existed with the consumption of cigarettes. Cotinine was measured in the following visits: baseline, and at 1, 2 and 4weeks after quitting smoking. Complete abstinence was defined as the total abstinence of smoking cigarettes from the day of cessation that is accompanied by CO levels in expired air equal to or less than 10 ppm. Results: A total of 187 smokers were included in the study: 103 women and 84 men. Mean age was 44.5. Complete abstinence index - of the 187 smokers who began the study, 156 (83%) remained abstinent at 4 weeks, 140 (74.8%) at 8 weeks and 125 (66.8%) at 12 weeks. The relationship between the abstinence index and obtaining of correct percentage of replacement was: at 3 months of follow-up in 129 subjects. A total of 106 out of the 129 (82.1%) subjects who obtained adequatere placement levels fulfilled complete abstinence criteria at the end of the 12 weeks and 23 (17.9%) failed. Nineteen out of 58 (32.7%) of the subjects who did not obtain adequate levels of replacement fulfilled complete abstinence criteria at the end of the 12 weeks of follow-up and 39 (67.3%) failed. Odds ratio 0.17 (0.07-0.33), p less than 0.0001. Conclusions: Adequate nicotine replacement in drug treatment of smoking cessation is associated significantly to the likelihood of cessation. A total of 70% of those in whom corinne was controlled in urine quit smoking at 12 weeks. Over all, the fraction that can be prevented by adjusting the cotinine levels during treatment has a 50% greater success compared to those in which it is not controlled (AU)

Smoking characteristics and cessation in patients with thromboangiitis obliterans.

AIM: Describe the smoking characteristics and the results of a smoking intervention programme involving 27 cigarette smokers with Thromboangiitis Obliterans (TAO). METHODS: Clinical records of all cigarette smokers with TAO that attended our smoking treatment clinic from 1990 to 2004 were reviewed. Demographic and smoking characteristics, the type of smoking treatment received and its efficacy and safety up to 12 months was abstracted. Treatment consisted of the combination of behavioural and pharmacological treatment. The behavioural treatment was delivered in eight individual visits: one baseline visit and seven follow-up visits. Pharmacological treatment consisted of combinations of nicotine patches and nicotine gum (NRT) and/or bupropion. This is an 'intent to treat' analysis. A descriptive analysis of the variables was performed. Qualitative variable relationships were tested using the chi-square test for independence, or Fisher's Exact Test when expected values were less than five. Statistical significance was accepted at a level of p < 0.05. RESULTS: 27 cigarette smokers (23 male and 4 female), mean (SD) age 36.07 (7.23), mean FTND-score 8.4 (1.4), smoked a mean of 29.6 (7.71) cigarettes daily. They attended our clinic a mean of 45.48 (8.63) months after onset of TAO. Their mean number of attempts to stop was 3.22 (2.75). The continuous abstinence rate decreased from 29% at the end of treatment to 18.5% at 12-month follow up. The seven day point prevalence abstinence rate at the 12th month of follow up was 40.7%. We found that continuous abstinence at 6 and 12 months was more frequent among those with multiple previous stop attempts (p = 0.003 and p = 0.001, respectively). There were no significant differences in abstinence outcomes between groups. Incidence of adverse effects was similar to other smokers seeking treatment. All the smokers who achieved continuous tobacco abstinence had improvement in their disease and none of them underwent amputation, compared to 50% of those who resumed smoking and later required an amputation. CONCLUSIONS: Continuous abstinence rates among treated cigarette smokers with TAO are relatively low, but abstinence does improve symptoms and reduce the likelihood of amputation. More aggressive treatment programmes need to be developed for this high risk, highly tobacco dependent population.

Ten-year population-based molecular epidemiological study of tuberculosis transmission in the metropolitan area of Madrid, Spain.

SETTING: The epidemiology of tuberculosis (TB) in urban populations is changing. Combining conventional epidemiological techniques with DNA fingerprinting of Mycobacterium tuberculosis can improve our understanding of how TB is transmitted. OBJECTIVE: To improve the definition of molecular epidemiology of TB over 10 years in an area of Europe not previously studied. DESIGN: A population-based retrospective study was conducted in the Autonomous Community of Madrid, Spain, from 1992 to 1998; from 1999 to 2001, the study was prospective. The study population consisted of all patients for whom positive culture and full clinical and demographic data were available. All strains were typed by RFLP. Non-clustered patients were compared with clustered patients and studied using univariate analysis and a logistic regression model. RESULTS: Of 448 patients studied, 228 (50.7%) were clustered. Youth was the strongest risk factor associated with clustering. Pleural effusion was also found to be associated with clustering. An epidemiological link was found in only 85 (37.4%) of the 228 patients belonging to a cluster. CONCLUSION: Youth and pleural effusion were identified as risk factors for clustering. These findings may help adjust TB control and contact tracing strategies.