OBJECTIVES: Aedes mosquitoes are responsible for transmitting the dengue virus. The mosquito lifecycle is known to be influenced by temperature, rainfall, and relative humidity. This retrospective study was planned to investigate whether climatic factors could be used to predict the occurrence of dengue in East Delhi. METHODS: The number of monthly dengue cases reported over 19 years was obtained from the laboratory records of our institution. Monthly data of rainfall, temperature, and humidity collected from a local weather station were correlated with the number of monthly reported dengue cases. One-way analysis of variance was used to analyse whether the climatic parameters differed significantly among seasons. Four models were developed using negative binomial generalized linear model analysis. Monthly rainfall, temperature, humidity, were used as independent variables, and the number of dengue cases reported monthly was used as the dependent variable. The first model considered data from the same month, while the other three models involved incorporating data with a lag phase of 1, 2, and 3 months, respectively. RESULTS: The greatest number of cases was reported during the post-monsoon period each year. Temperature, rainfall, and humidity varied significantly across the pre-monsoon, monsoon, and post-monsoon periods. The best correlation between these three climatic factors and dengue occurrence was at a time lag of 2 months. CONCLUSIONS: This study found that temperature, rainfall, and relative humidity significantly affected dengue occurrence in East Delhi. This weather-based dengue empirical model can forecast potential outbreaks 2-month in advance, providing an early warning system for intensifying dengue control measures.
Aedes ; Culicidae ; Dengue Virus ; Dengue* ; Disease Outbreaks ; Humidity* ; Incidence* ; Linear Models ; Retrospective Studies* ; Seasons ; Weather

An undifferentiated carcinoma (UC) of the gall bladder behaves aggressively and has a grave prognosis. Small cell type undifferentiated carcinoma of the gall bladder is a rare variant. This paper reports a case of UC of gall bladder with PAS-positive diastase-resistant eosinophilic hyaline globules present as liver mass (on imaging) in a male patient. The microscopic findings of the liver and gall bladder after a right tri-segmentectomy showed an un-differentiated malignant neoplasm composed of cells with round to oval nuclei, prominent nucleoli, and scanty neoplasm. No definite cell pattern was identified with these neoplastic cells. A section from the gall bladder revealed a tumor arising from the lining epithelium and infiltrating through the muscularis. This tumor was infiltrating the adherent liver tissue directly and forming a mass of undifferentiated malignant cells. The focal area within the tumor mass showed the presence of PAS-positive, diastase-resistant, eosinophilic hyaline globules within the neoplastic cells. The immunohistochemistry test was diffusely positive for perinuclear anti-neutrophil cytoplasmic antibodies and negative for chromogranin, vimentin, Desmin, alpha-fetoprotein, leukocyte common antigen, CD34, and bcl2. When the clinical and radiological data are inconclusive, careful analysis of the histological and immunophenotypic features is needed to make the final diagnosis of UC of the gall bladder. The biological behavior and prognosis of this tumor remain unclear because of its rarity. Further studies will be needed to understand the characteristics of this deadly tumor and to establish an effective therapy for it.