Seasonal patterns of dengue fever in rural Ecuador: 2009—2016 Seasonality of dengue fever in Ecuador

AbstractSeason is a major determinant of infectious disease rates, including arboviruses spread by mosquitoes, such as dengue, chikungunya, and Zika. Seasonal patterns of disease are driven by a combination of climatic or environmental factors, such as temperature or rainfall, and human behavioral time trends, such as school year schedules, holidays, and weekday-weekend patterns. These factors affect both disease rates and healthcare-seeking behavior. Seasonality of dengue fever has been studied in the context of climatic factors, but short- and long-term time trends are less well-understood. With 2009—2016 medical record data from patients diagnosed with dengue fever at two hospitals in rural Ecuador, we used Poisson generalized linear modeling to determine short- and long-term seasonal patterns of dengue fever, as well as the effect of day of the week and public holidays. In a subset analysis, we determined the impact of school schedules on school-aged children. With a separate model, we examined the effect of climate on diagnosis patterns. In the first model, the most important predictors of dengue fever were annual sinusoidal fluctuations in disease, long-term trends (as represented by a spline for the full study duration), day of the week, and hospital. Seasonal trends showed single peaks in case diagnoses, during mid-March. Compared to the average of all days, cases were more likely to be diagnosed on Tuesdays (risk ratio (RR): 1.26, 95% confidence interval (CI) 1.05—1.51) and Thursdays (RR: 1.25, 95% CI 1.02—1.53), and less likely to be diagnosed on Saturdays (RR: 0.81, 95% CI 0.65—1.01) and Sundays (RR: 0.74, 95% CI 0.58—0.95). Public holidays were not significant predictors of dengue fever diagnoses, except for an increase in diagnoses on the day after Christmas (RR: 2.77, 95% CI 1.46—5.24). School schedules did not impact dengue diagnoses in school-aged children. In the climate model, important climate variables included the monthly total precipitation, an interaction between total precipitation and monthly absolute minimum temperature, an interaction between total precipitation and monthly precipitation days, and a three-way interaction between minimum temperature, total precipitation, and precipitation days. This is the first report of long-term dengue fever seasonality in Ecuador, one of few reports from rural patients, and one of very few studies utilizing daily disease reports. These results can inform local disease prevention efforts, public health planning, as well as global and regional models of dengue fever trends.Author summaryDengue fever exhibits a seasonal pattern in many parts of the world, much of which has been attributed to climate and weather. However, additional factors may contribute to dengue seasonality. With 2009— 2016 medical record data from rural Ecuador, we studied the short- and long-term seasonal patterns of dengue fever, as well as the effect of school schedules and public holidays. We also examined the effect of climate on dengue. We found that dengue diagnoses peak once per year in mid-March, but that diagnoses are also affected by day of the week. Dengue was also impacted by regional climate and complex interactions between local weather variables. This is the first report of long-term dengue fever seasonality in Ecuador, one of few reports from rural patients, and one of very few studies utilizing daily disease reports. This is the first report on the impacts of school schedules, holidays, and weekday-weekend patterns on dengue diagnoses. These results suggest a potential impact of human behaviors on dengue exposure risk. More broadly, these results can inform local disease prevention efforts and public health planning, as well as global and regional models of dengue fever trends.

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A date to remember: the nature of memory in savant calendrical calculators

Psychological Medicine ◽

10.1017/s0033291798007776 ◽

1999 ◽

Vol 29 (1) ◽

pp. 145-160 ◽

Cited By ~ 43

Author(s):

L. HEAVEY ◽

L. PRING ◽

B. HERMELIN

Keyword(s):

Cognitive Processing ◽

Memory Function ◽

Long Term Memory ◽

Term Memory ◽

Processing Style ◽

Calculation Skills ◽

Short And Long Term ◽

Day Of The Week ◽

Better Than

Background. Savant calendar calculators can supply with speed the day of the week of a given date. Although memory is suggested to be an important component of this unusual ability, memory function has never been systematically investigated in these skilled yet learning impaired individuals.Methods. Eight savant calendrical calculators, most of whom had autism, were compared with eight verbal IQ, age and diagnosis matched controls on digit and word span tests and measures of long-term memory for words and calendrical information (individual years). In an analogue to the ‘generation effect’, the savants' memory for dates was also compared following calculation and study/read tasks.Results. The savants did not differ from controls on measures of general short- and long-term memory. They did, however, show a clear recall superiority for the long-term retention of calendrical material. They also remembered calculated dates better than those that were only studied.Conclusions. A general mnemonic advantage cannot explain savant date calculation skills. Rather, through exposure to date information, the savants are suggested to develop a structured calendar-related knowledge base with the process of calculation utilizing the interrelations within this knowledge store. The cognitive processing style characteristic of autism may also play a role in the acquisition of this savant ability.

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Comparison of statistical algorithms for syndromic surveillance aberration detection

Online Journal of Public Health Informatics ◽

10.5210/ojphi.v10i1.8302 ◽

2018 ◽

Vol 10 (1) ◽

Author(s):

R. Morbey ◽

A. Noufaily ◽

F. D. Colón-González ◽

A. Elliot ◽

S. Harcourt ◽

...

Keyword(s):

Public Health ◽

Sensitivity And Specificity ◽

Syndromic Surveillance ◽

Mixed Effects ◽

Outbreak Detection ◽

Aberration Detection ◽

Day Of The Week ◽

Multi Level ◽

Public Holidays

ObjectiveTo investigate whether alternative statistical approaches can improve daily aberration detection using syndromic surveillance in England.IntroductionSyndromic surveillance involves monitoring big health datasets to provide early warning of threats to public health. Public health authorities use statistical detection algorithms to interrogate these datasets for aberrations that are indicative of emerging threats. The algorithm currently in use at Public Health England (PHE) for syndromic surveillance is the ‘rising activity, multi-level mixed effects, indicator emphasis’ (RAMMIE) method (Morbey et al, 2015), which fits a mixed model to counts of syndromes on a daily basis. This research checks whether the RAMMIE method works across a range of public health scenarios and how it compares to alternative methods.MethodsFor this purpose, we compare RAMMIE to the improved quasi-Poisson regression-based approach (Noufaily et al, 2013), currently implemented at PHE for weekly infectious disease laboratory surveillance, and to the Early Aberration Reporting System (EARS) method (Rossi et al, 1999), which is used for syndromic surveillance aberration detection in many other countries. We model syndromic datasets, capturing real data aspects such as long-term trends, seasonality, public holidays, and day-of-the-week effects, with or without added outbreaks. Then, we compute the sensitivity and specificity to compare how well each of the algorithms detects synthetic outbreaks to provide recommendations for the most suitable statistical methods to use during different public health scenarios.ResultsPreliminary results suggest all methods provide high sensitivity and specificity, with the (Noufaily et al, 2013) approach having the highest sensitivity and specificity. We showed that for syndromes with long-term increasing trends, RAMMIE required modificaiton to prevent excess false alarms. Also, our study suggests further work is needed to fully account for public holidays and day-of-the-week effects.ConclusionsOur study will provide recommendations for which algorithm is most effective for PHE's syndromic surveillance for a range of different syndromes. Furthermore our work to generate standardised synthetic syndromic datasets and a range of outbreaks can be used for future evaluations in England and elsewhere.ReferencesNoufaily, A., Enki, D. G., Farrington, C. P., Garthwaite, P., Andrews, N. and Charlett, A. (2013). An Improved Algorithm for Outbreak Detection in Multiple Surveillance Systems. Statistics in Medicine, 32(7), 1206-1222.Morbey, R. A., Elliot, A. J., Charlett, A., Verlander, A. Q, Andrews, N. and Smith, G. (2013). The application of a novel ‘rising activity, multi-level mixed effects, indicator emphasis’ (RAMMIE) method for syndromic surveillance in England, Bioinformatics, 31(22), 3660-3665.Rossi, G, Lampugnani, L, Marchi, M. (1999), An approximate CUSUM procedure for surveillance of health events. Statistics in Medicine, 18, 2111–2122

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Hospital usage of TOXBASE in Great Britain: Temporal trends in accesses 2008 to 2015

Human & Experimental Toxicology ◽

10.1177/0960327118759405 ◽

2018 ◽

Vol 37 (11) ◽

pp. 1207-1214 ◽

Cited By ~ 1

Author(s):

K Pyper ◽

M Eddleston ◽

DN Bateman ◽

D Lupton ◽

S Bradberry ◽

...

Keyword(s):

Generalized Additive Models ◽

Temporal Trends ◽

Emergency Admission ◽

Additive Models ◽

Seasonal Patterns ◽

Long Term Trends ◽

Day Of The Week ◽

Future Work ◽

Long Term Trend

Aim: To examine temporal trends in accesses to the UK’s National Poison Information Service’s TOXBASE database in Britain. Methods: Generalized additive models were used to examine trends in daily numbers of accesses to TOXBASE from British emergency departments between January 2008 and December 2015. Day-of-the-week, seasonality and long-term trends were analysed at national and regional levels (Wales, Scotland and the nine English Government Office Regions). Results: The long-term trend in daily accesses increases from 2.8 (95% confidence interval (CI): 2.6–3.0) per user on 1 January 2008 to 4.6 (95% CI: 4.3–4.9) on 31 December 2015, with small but significant differences in population-corrected accesses by region ( p < 0.001). There are statistically significant seasonal and day of the week patterns ( p < 0.001) across all regions. Accesses are 18% (95% CI: 14–22%) higher in summer than in January and at the weekend compared to weekdays in all regions; there is a 7.5% (95% CI: 6.1–8.9%) increase between Friday and Sunday. Conclusions: There are consistent in-year patterns in access to TOXBASE indicating potential seasonal patterns in poisonings in Britain, with location-dependent rates of usage. This novel descriptive work lays the basis for future work on the interaction of TOXBASE use with emergency admission of patients into hospital.

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Effect of day of the week on short- and long-term mortality after emergency general surgery

British Journal of Surgery ◽

10.1002/bjs.10507 ◽

2017 ◽

Vol 104 (7) ◽

pp. 936-945 ◽

Cited By ~ 15

Author(s):

M. A. Gillies ◽

N. I. Lone ◽

R. M. Pearse ◽

C. Haddow ◽

L. Smyth ◽

...

Keyword(s):

General Surgery ◽

Emergency General Surgery ◽

Short And Long Term ◽

Day Of The Week ◽

Long Term Mortality

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Experience with Short and Long Term Courses of Local Adrenal Steroid Therapy For Ulcerative Colitis

Gastroenterology ◽

10.1016/s0016-5085(62)80117-6 ◽

1962 ◽

Vol 42 (6) ◽

pp. 669-677 ◽

Cited By ~ 18

Author(s):

Jean A. Spencer ◽

Joseph B. Kirsner

Keyword(s):

Ulcerative Colitis ◽

Steroid Therapy ◽

Adrenal Steroid ◽

Short And Long Term

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Short- and Long-Term Results of Total vs Subtotal Thyroid- ectomies in the Surgical Treatment of Graves' Disease

Swiss Surgery ◽

10.1024/1023-9332.7.1.20 ◽

2001 ◽

Vol 7 (1) ◽

pp. 20-24 ◽

Cited By ~ 14

Author(s):

Robert ◽

Mariéthoz ◽

Pache ◽

Bertin ◽

Caulfield ◽

...

Keyword(s):

Recurrent Laryngeal Nerve ◽

Nerve Palsy ◽

Recurrent Laryngeal Nerve Palsy ◽

Laryngeal Nerve ◽

Long Term Results ◽

Graves Disease ◽

Laryngeal Nerve Palsy ◽

Short And Long Term

Objective: Approximately one out of five patients with Graves' disease (GD) undergoes a thyroidectomy after a mean period of 18 months of medical treatment. This retrospective and non-randomized study from a teaching hospital compares short- and long-term results of total (TT) and subtotal thyroidectomies (ST) for this disease. Methods: From 1987 to 1997, 94 patients were operated for GD. Thirty-three patients underwent a TT (mostly since 1993) and 61 a ST (keeping 4 to 8 grams of thyroid tissue - mean 6 g). All patients had received propylthiouracil and/or neo-mercazole and were in a euthyroid state at the time of surgery; they also took potassium iodide (lugol) for ten days before surgery. Results: There were no deaths. Transient hypocalcemia (< 3 months) occurred in 32 patients (15 TT and 17 ST) and persistent hypocalcemia in 8 having had TT. Two patients developed transient recurrent laryngeal nerve palsy after ST (< 3 months). After a median follow-up period of seven years (1-15) with five patients lost to follow-up, 41 patients having had a ST are in a hypothyroid state (73%), thirteen are euthyroid (23%), and two suffered recurrent hyperthyroidism, requiring completion of thyroidectomy. All 33 patients having had TT - with follow-ups averaging two years (0.5-8) - are receiving thyroxin substitution. Conclusions: There were no instances of persistent recurrent laryngeal nerve palsy in either group, but persistent hypoparathyroidism occurred more frequently after TT. Long after ST, hypothyroidism developed in nearly three of four cases, whereas euthyroidy was maintained in only one-fourth; recurrent hyperthyroidy was rare.

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