Paradox between adequate sanitation and rainfall in dengue fever cases.

BACKGROUND: Dengue fever is a tropical disease and a major public health concern, and almost half of the world's population lives in areas at risk of contracting this disease. Climate change is identified by WHO and other international health authorities as one of the primary factors that contribute to the rapid spread of dengue fever. METHODS: We evaluated the effect of sanitation on the cross-correlation between rainfall and the first symptoms of dengue in the city of Mato Grosso do Sul, which is in a state in the Midwest region of Brazil, and employed the time-lagged detrended cross-correlation analysis (DCCAC) method. RESULTS: Co-movements were obtained through the time-phased DCCAC to analyze the effects of climatic variables on arboviruses. The use of a time-lag analysis was more robust than DCCAC without lag to present the behavior of dengue cases in relation to accumulated precipitation. Our results show that the cross-correlation between rain and dengue increased as the city implemented actions to improve basic sanitation in the city. CONCLUSION: With climate change and the increase in the global average temperature, mosquitoes are advancing beyond the tropics, and our results show that cities with improved sanitation have a high correlation between dengue and annual precipitation. Public prevention and control policies can be targeted according to the period of time and the degree of correlation calculated to structure vector control and prevention work in places where sanitation conditions are adequate.

Safety assessment of Hibiscus sabdariffa after maternal exposure on male reproductive parameters in rats.

CONTEXT: Hibiscus sabdariffa L. (Malvaceae) is a species widely used in folk medicine for the treatment of some disorders. OBJECTIVE: This study evaluated the effects of H. sabdariffa (HS) on the development of the male reproductive tract in rats following in utero exposure. MATERIALS AND METHODS: Pregnant rats received 250 or 500 mg/kg of HS extract or vehicle from gestational day 12 until day 21 of lactation. RESULTS AND DISCUSSION: Both doses of HS increased the body weight of male offspring at weaning, without compromising the puberty onset parameters. At puberty, there was a significant increase in the vas deferens absolute weight and a significant reduction in the relative weight of kidney at higher dose. These animals also presented a significant reduction in the sperm number in the caput/corpus of epididymis after exposure to both doses and a reduction in the sperm number in the cauda epididymis for the lower dose. At adulthood, the highest dose significantly reduced the sperm production in relation to controls and both doses provoked a reduction in the relative sperm number in the epididymis without affecting the sperm morphology. CONCLUSION: These findings demonstrated that maternal exposure to H. sabdariffa can adversely influence the male reproductive system in rats.

Maternal exposure to aqueous extract of Jacaranda decurrens: effects on reproductive system in male rats.

CONTEXT: Jacaranda decurrens subsp. symmetrifoliolata Farias & Proença (Bignoniaceae) is a species widely used for their medicinal properties. At least to our known, no study has been conducted concerning its toxicological profile after gestational and lactational exposure. OBJECTIVE: The present study was carried out to evaluate the effects of J. decurrens on development of the reproductive system in male rats. MATERIALS AND METHODS: Pregnant rats were treated daily (gavage) with 250 or 500 mg/kg/day of aqueous extract of J. decurrens or vehicle, from day 12 of pregnancy to day 21 of lactation. RESULTS AND DISCUSSION: Both doses of J. decurrens significantly anticipated (p < 0.05) the age of testicular descent to the scrotum, a parameter indicative of puberty initiation. Furthermore, at puberty, there was a significant reduction (p < 0.05) in testicular and epididymis weights in the offspring exposed to the higher dose of extract, without effect on sperm production and the histology of reproductive organs. On the other hand, at adulthood, the reproductive parameters analyzed did not differ among groups. CONCLUSIONS: J. decurrens, in this experimental model, interfered with the initial development of the reproductive system, but without lasting effects on sperm production in adulthood.