Potential impact of macroclimatic variability on the epidemiology of giardiasis in three provinces of Cuba, 2010-2012

The Influence of Climate and Livestock Reservoirs on Human Cases of Giardiasis

Giardia duodenalis is an intestinal parasite which causes diarrhoeal illness in people. Zoonotic subtypes found in livestock may contribute to human disease occurrence through runoff of manure into multi-use surface water. This study investigated temporal associations among selected environmental variables and G. duodenalis occurrence in livestock reservoirs on human giardiasis incidence using data collected in the Waterloo Health Region, Ontario, Canada. The study objectives were to: (1) evaluate associations between human cases and environmental variables between 1 June 2006 and 31 December 2013, and (2) evaluate associations between human cases, environmental variables and livestock reservoirs using a subset of this time series, with both analyses controlling for seasonal and long-term trends. Human disease incidence exhibited a seasonal trend but no annual trend. A Poisson multivariable regression model identified an inverse association with water level lagged by 1 month (IRR = 0.10, 95% CI 0.01, 0.85, P < 0.05). Case crossover analysis found varying associations between lagged variables including livestock reservoirs (1 week), mean air temperature (3 weeks), river water level (1 week) and flow rate (1 week), and precipitation (4 weeks). This study contributes to our understanding of epidemiologic relationships influencing human giardiasis cases in Ontario, Canada.

The association between temperature, rainfall and humidity with common climate-sensitive infectious diseases in Bangladesh

Bangladesh is one of the world's most vulnerable countries for climate change. This observational study examined the association of temperature, humidity and rainfall with six common climate-sensitive infectious diseases in adults (malaria, diarrheal disease, enteric fever, encephalitis, pneumonia and bacterial meningitis) in northeastern Bangladesh. Subjects admitted to the adult medicine ward of a tertiary referral hospital in Sylhet, Bangladesh from 2008 to 2012 with a diagnosis of one of the six chosen climate-sensitive infectious diseases were enrolled in the study. Climate-related data were collected from the Bangladesh Meteorological Institute. Disease incidence was then analyzed against mean temperature, humidity and average rainfall for the Sylhet region. Statistical significance was determined using Mann-Whitney test, Chi-square test and ANOVA testing. 5033 patients were enrolled (58% male, 42% female, ratio 1.3:1). All six diseases showed highly significant (p = 0.01) rises in incidence between the study years 2008 (540 cases) and 2012 (1330 cases), compared with no significant rise in overall all-cause hospital admissions in the same period (p = 0.19). The highest number of malaria (135), diarrhea (266) and pneumonia (371) cases occurred during the rainy season. On the other hand, the maximum number of enteric fever (408), encephalitis (183) and meningitis (151) cases occurred during autumn, which follows the rainy season. A positive (P = 0.01) correlation was observed between increased temperature and the incidence of malaria, enteric fever and diarrhea, and a negative correlation with encephalitis, meningitis and pneumonia. Higher humidity correlated (P = 0.01) with a higher number of cases of malaria and diarrhea, but inversely correlated with meningitis and encephalitis. Higher incidences of encephalitis and meningitis occurred while there was low rainfall. Incidences of diarrhea, malaria and enteric fever, increased with rainfall, and then gradually decreased. The findings support a relationship between weather patterns and disease incidence, and provide essential baseline data for future large prospective studies.

Impact of climate change on occupational health and productivity: a systematic literature review focusing on workplace heat

BACKGROUND

With climate change, mean annual air temperatures are getting hotter and extreme weather events will become more and more common in most parts of the world.

OBJECTIVES

As part of the EU funded project HEAT-SHIELD we conducted a systematic review to summarize the epidemiological evidence of the effects of global warming-related heat exposure on workers' health and productivity.

METHODS

Three separate searches, focused, respectively, on: i) heat-related illness (HRI), cardiovascular, respiratory and kidney diseases; ii) traumatic injuries; and iii) vector-borne diseases or vectors distribution, were conducted in PubMed. EMBASE was also consulted to retrieve relevant studies focused on the health effects of climate change. A fourth search strategy to assess the effects on work productivity was conducted both in PubMed and in the SCOPUS database.

RESULTS

A significant proportion of studies reported findings regarding the Mesoamerican nephropathy issue. This is a disease occurring especially among young and middle-aged male sugarcane workers, without conventional risk factors for chronic kidney disease. For injuries, there is a reversed U-shaped exposure-response relationship between Tmax and overall daily injury claims. Outdoor workers are at increased risk of vector-borne infectious diseases, as a positive correlation between higher air temperatures and current or future expansion of the habitat of vectors is being observed. As for productivity, agriculture and construction are the most studied sectors; a day with temperatures exceeding 32°C can reduce daily labour supply in exposed sectors by up to 14%.

CONCLUSIONS

The present findings should inform development of further research and related health policies in the EU and beyond with regard to protecting working people from the effects of workplace heat during climate change.

Estimating and mapping the incidence of giardiasis in Colombia, 2009-2013

BACKGROUND

Giardiasis is one of the most common intestinal infections in the world. There have been no national studies on the morbidity of giardiasis in Colombia. In this study, incidence rates of giardiasis were estimated for the years 2009-2013.

METHODS

An observational, retrospective study of the giardiasis incidence in Colombia, 2009-2013, was performed using data extracted from the personal health records system (Registro Individual de Prestación de Servicios, RIPS). Official population estimates from the National Department of Statistics (DANE) were used for the estimation of crude and adjusted incidence rates (cases/100 000 population).

RESULTS

During the period studied, 15 851 cases were reported (median 3233/year; 5-year cumulated crude national rate of 33.97 cases/100 000 population). Of these, 50.3% were female; 58.4% were <10 years old and 14.8% were 10-19 years old. By region, 17.7% were from Bogotá (10.07 cases/100 000 population, 2009), 10.9% from Antioquia (9.42, 2009), 8.6% from Atlántico (15.67, 2009), and 6.5% from Risaralda (33.38, 2009). Cases were reported in all departments (even insular areas).

CONCLUSIONS

As giardiasis is neglected in many countries, surveillance is not regularly undertaken. Despite its limitations, this study is the first attempt to provide estimates of national giardiasis incidence with consistent findings regarding affected age groups and geographical distribution.