Weather variables as important clinical predictors of bacterial diarrhoea among international travellers

Incidence and risk factors for travellers' diarrhoea among short-term international adult travellers from high-income countries: a systematic review with meta-analysis of cohort studies

INTRODUCTION

Travellers' diarrhoea (TD) continues to be the most common travel-related medical event in international travellers. Updated incidence and risk factor data will improve pre-travel medical advice for travellers from high-income countries (HICs), providing an opportunity for disease prevention and appropriate disease management.

METHODS

A systematic search for cohort studies of TD incidence published between 1 January 1997 and 2 March 2023 was performed using Ovid Medline, SCOPUS and Google Scholar databases. Study quality was assessed with a modified Newcastle-Ottawa Scale (NOS). We extracted incidence data for adults travelling less than 100 days from HIC and available risk factor data. The overall random-effects pooled incidence and the corresponding 95% confidence intervals (95% CI) were estimated. Heterogeneity was assessed using the I2 statistic, tau and the 95% prediction intervals. Subgroup analyses were conducted to identify the sources of heterogeneity. Risk factor studies were reviewed qualitatively and described.

RESULTS

Ten studies were included in the meta-analysis, containing 8478 participants. Two of the studies measured as high quality and eight as good quality as assessed by the modified NOS. The TD incidence was 36.1% (95% CI 24-41%; I2 94%), with a prediction interval ranging from 20.3 to 55.8%. The pooled incidence of mild, moderate and severe TD was 23.6, 8.1 and 2.9%, respectively. Subgroup analysis showed that the incidence increased with increasing average data collection period. Risk factors for TD in travellers from HIC identified include younger age, longer travel periods, low and middle-income destinations, travelling for tourism, backpacking travel styles and pre-travel health status.

CONCLUSION

It is estimated that between 20 and 56% of international travellers can expect to develop TD in travel of under 100 days. While most cases are mild, ~3% of all travellers will experience a disease that prevents usual activities or requires medical attention.

Medical meteorological forecast for ischemic stroke: random forest regression vs long short-term memory model

Ischemic stroke (IS) is one of the top risk factors for death and disability. Meteorological conditions have an effect on IS attack. In this study, we try to develop models of medical meteorological forecast for IS attack based on machine learning and deep learning algorithms. The medical meteorological forecast would be beneficial to public health in IS events prevention and treatment. We collected data on IS attacks and climatology in each day from 18th September 2016 to 31th December 2020 in Haikou. Data on IS attacks were from the number of hospital admissions due to IS attack among general population. The random forest (RF) regression and long short-term memory (LSTM) algorithms were respectively used to develop the predictive model based on meteorological data. Performance of the model was assessed by mean squared error (MSE) and root mean squared error (RMSE). A total of 42849 IS attacks was included in this study. IS attacks were significantly decreased in winter. The pattern of climatological data was observed the regularity in seasons. For the performance of RF regression model, the MSE is 243, and the RMSE is 15.6. For LSTM model, the MSE is 36, and the RMSE is 6. In conclusion, LSTM model is more accurate than RF regression model to predict IS attacks in general population based on meteorological data. LSTM model showed acceptable accuracy for the prediction and could be used as medical meteorological forecast to predict IS attack among population according to local climate.

Evaluation of Fecal Inflammatory Biomarkers to Identify Bacterial Diarrhea Episodes: Systematic Review and Protocol for the Enterics for Global Health Shigella Surveillance Study

Background

The measurement of fecal inflammatory biomarkers among individuals presenting to care with diarrhea could improve the identification of bacterial diarrheal episodes that would benefit from antibiotic therapy. We reviewed prior literature in this area and describe our proposed methods to evaluate 4 biomarkers in the Enterics for Global Health (EFGH) Shigella surveillance study.

Methods

We systematically reviewed studies since 1970 from PubMed and Embase that assessed the diagnostic characteristics of inflammatory biomarkers to identify bacterial diarrhea episodes. We extracted sensitivity and specificity and summarized the evidence by biomarker and diarrhea etiology. In EFGH, we propose using commercial enzyme-linked immunosorbent assays to test for myeloperoxidase, calprotectin, lipocalin-2, and hemoglobin in stored whole stool samples collected within 24 hours of enrollment from participants in the Bangladesh, Kenya, Malawi, Pakistan, Peru, and The Gambia sites. We will develop clinical prediction scores that incorporate the inflammatory biomarkers and evaluate their ability to identify Shigella and other bacterial etiologies of diarrhea as determined by quantitative polymerase chain reaction (qPCR).

Results

Forty-nine studies that assessed fecal leukocytes (n = 39), red blood cells (n = 26), lactoferrin (n = 13), calprotectin (n = 8), and myeloperoxidase (n = 1) were included in the systematic review. Sensitivities were high for identifying Shigella, moderate for identifying any bacteria, and comparable across biomarkers. Specificities varied depending on the outcomes assessed. Prior studies were generally small, identified red and white blood cells by microscopy, and used insensitive gold standard diagnostics, such as conventional bacteriological culture for pathogen detection.

Conclusions

Our evaluation of inflammatory biomarkers to distinguish diarrhea etiologies as determined by qPCR will provide an important addition to the prior literature, which was likely biased by the limited sensitivity of the gold standard diagnostics used. We will determine whether point-of-care biomarker tests could be a viable strategy to inform treatment decision making and increase appropriate targeting of antibiotic treatment to bacterial diarrhea episodes.

Infections transmitted via the faecal-oral route: a simple score for a global risk map

INTRODUCTION

Faecal-oral transmission refers to the process whereby disease is transmitted via the faeces of an infected individual to the mouth of a susceptible individual. This transmission can occur through failures in sanitation systems leading to exposure via various routes in particular contaminated water, food, and hands. Travellers' diarrhoea is the most common travel-related illness. A score could enhance risk assessment and pre-travel advice.

METHODS

A simple score was developed based on the frequency of defecating in the open (country prevalence > 1%), occurrence of cholera in the period between 2021 and 2017 (one or more case in a country) and reported typhoid fever cases between 2015 and 2019.

RESULTS

Data were available for 199 out of 214 countries for the score to be applied. 19% of the 199 countries scored as high risk countries for faecal-oral transmission (score 3), 47% as medium risk (score 2), and 34% as minimal risk (score 0). The percentage of countries scoring 3 was highest in Africa (63%) and lowest in Europe and Oceania (score 0).

CONCLUSIONS

A global risk map was developed based on a simple score that could aid travel medicine providers in providing pre-travel risk assessment. For travellers to high and medium risk countries, pre-travel consultation must include detailed advice on food and water hygiene.

Clinical characteristics and influencing factors of infectious diarrhea in preschool children: An observational study

Infectious diarrhea is a common disease in preschool children, but the pathogenic species, origins, and influencing factors remain debatable. Therefore, more studies are required to solve these debatable topics. A number of 260 eligible preschool children diagnosed with infectious diarrhea in our hospital were enrolled in the infection group. Meanwhile, a number of 260 matched healthy children from the health center were enrolled in the control group. The pathogenic species and origins, the time of onset of infectious diarrhea in the infection group, demographic data, exposure history, hygiene habits, dietary habits, and other variables in both groups were initially collected from medical documents. In addition, a questionnaire was used to complete and confirm study variables through face-to-face or telephone interviews. Then, the univariate and multivariate regression analyses were used to screen the influencing factors of infectious diarrhea. Among 260 infected children, salmonella (15.77%), rotavirus (13.85%), shigella (11.54%), vibrio (10.38%), and norovirus (8.85%) were the top 5 common pathogens; January (13.85%), December (12.69%), August (12.31%), February (11.92%), and July (8.46%) were the top 5 frequent times of infectious diarrhea. The distribution of onset time for infectious diarrhea was commonly found in winter and summer, and the pathogens always originated from foods. The results of multivariate regression analysis showed that recent exposure to diarrhea, flies, and/or cockroaches indoors were the 2 risk factors for infectious diarrhea; Meanwhile, rotavirus vaccination, regular hand-washing, tableware disinfection, separate preparation of cooked and raw foods, and regular intake of lactobacillus products were the 5 protective factors for infectious diarrhea in preschool children. Infectious diarrhea has a diversity of pathogenic species, origins, and influencing factors in preschool children. Activities focusing on these influencing factors such as rotavirus vaccination, consumption of lactobacillus products, and other conventional factors would be beneficial to preschool children's health.