Population ecology of mosquitoes and the status of bancroftian filariasis in el Dakahlia governorate, the Nile Delta, Egypt

Mosquitoes were surveyed [Oct. 2010 and Apr. - Oct. 2011] in some localities representing 13 centers of El-Dakahlia Governorate. Six mosquito species were collected: Culex pipiens, Cx. antennatus, Cx. perexiguus, Ochlerotatus detritus, Anopheles pharoensis and An. tenebrosus. Culex pipiens was predominating [ca 79% larvae, 51% adults]. Culex antennatus and Cx. perexiguus were also common. Of the Four types of the breeding habitats, the drainage canals were the most productive [53.4% larvae]. For the three common species, the compiled larval density increases as water temp, increased and decreases as pH increased while adult indoor density increases as indoor and outdoor temp, and indoor RH increased and decreases as outdoor RH increased. Cx. pipiens significantly associated with Cx. antennatus [C[AB]=0.88 and I=0.48] while Cx. antennatus has a moderate association with Cx. perexiguus [C[AB]=0.47 and I=0.36]. Out of 908 examined blood samples from ten centers, 7.49% were infected with Wuchereria bancrofti. The highest infection rates in some centers were associated with high indoor densities of Cx. pipiens females, the main filariasis vector. The situation necessitates a wide vector control program to minimize lymphatic filariasis transmission in this Governorate

Geographical distribution and relative abundance of culicine mosquitoes in relation to transmission of lymphatic filariasis in El Menoufia Governorate, Egypt

Culicine mosquito were surveyed in El Menoufia Governorate [October to November 2008 and April to May 2009] in villages representing eight districts. Six species were reported: Culex [Culex] pipiens Linnaeus, Cx. [Cx] perexiguus Theobald, Cx. [Cx.] antennatus [Becker], Aedes [Ochlerotatus] caspius [Pallas], Aedes [Ochlerotatus] detritus [Haliday] and Culiseta [Allotheobaldia] longiareolata [Macquart]. Cx. pipiens, the main filariasis vector was the commonest or predominating species [ca. 47% adults and 92% larvae, P<0.01]. For the common species, the following were investigated: 1-temperature and pH of the breeding habitats and their relation to the larval density and 2-relation of adult indoor density with indoor-and outdoor-temperature and RH. Besides, parasitologically, Wuchereria bancrofti cases [33/631 blood samples, 5.23%] were detected in three districts [range=1.96-14.12% infection]. The cases were associated with the abundance of Cx. pipiens adults [ca. 45-62% of the collected adults]

Mosquitoes [diptera: culicidae] in relation to the risk of disease transmission in el Ismailia Governorate, Egypt

Mosquito were surveyed [Nov. 2009 - March 2010] in El Ismailia Governorate. Nine species were reported: Culex pipiens, Cx. perexiguus, Cx. antennatus, Anopheles tenebrosus, An. pharoensis, An. multicolor, Ochlerotatus detritus, Oc. cas-pius and Culiseta longiareolata. Culex pipiens was the predominant species [ca. 87% larvae and 57% adults]. For the 3 common species, Cx. pipiens, Cx. perexiguus, and Cx. antennatus the following were examined: [1] the type and characteristics [temperature and pH] of the breeding habitats and their relation to the larval density and [2] the relation of adult indoor density to the indoor and outdoor temperature and RH. The abundance of mosquito vectors in El Ismailia with its old history of vector transmitted diseases contributes to the risk of mosquito borne disease transmission in this area. This would assist in the control activities

Susceptibility of bromadiolone anticoagulant rodenticide in two rodent species and its haematologic effect

Susceptibility levels of the Norway rat, Rattus norvegicus and the roof rat, Rattus rattus to bromadiolone anticoagulant rodenticide by bioassay and biochemical methods were studied. Animals were trapped from Giza and Qualyobia Governorates in which the anticoagulant rodenticides were used to control rodents for long periods. Complete mortality was obtained for both species and sexes within standard no-choice feeding test period [4 days] indicating bromadiolone susceptibility. Treatment of rats with LD50 showed high prothrombin times which also indicate the susceptibility of the tested animals. In treated rats, bromadiolone caused significant decrease in the total erythrocytic counts and increase in the total leucocytic counts. In survivors, RBCs, WBCs approximately reached the control levels at day 43 post treatment. Also, treatment decreased neutrophils, eosinophils, basophils and monocytes but increased the lymphocytes in dead and survived animals more than in controls

Hematological changes in mice exposed to biting of the bedbug: Cimex lectularius L. [Hemiptera: Cimicidae]

The studies on hematologic changes in humans or animals as a result of bedbug bites are lacking. This study was undertaken to examine changes in the blood picture of mice [Mus musculus] exposed to Cimex lectularius biting. As compared to the check animals, mice exposed to bedbug bites either once or twice within 7 days showed insignificantly higher WBC's [1.6 and 2.8% increase, respectively] and lower HGB content [0.5 and 0.8% decrease, respectively] and significantly higher PLT's [P<0.01] by 2.2% and 3.0%, respectively. Significantly higher [P<0.01] RBC's counts in mice bitten once than those of normal animals or those exposed to twice bites [5.3 and 5.9% increase, respectively]. Bedbug biting exerts its effects largely upon the differential WBC's. Mice bitten once or twice showed significantly lower number of neutrophils [1.2% and 12.1% decrease, respectively] than those for normal animals. Mice exposed to twice bites showed significantly [P<0.01] higher numbers of lymphocyte [18.8%], monocyte [13.6%], eosinophil [200.0%] and basophil [500%] than those of normal mice

Effect of warfarin anticoagulant rodenticide on the blood cell counts of Rattus norvegicus and Rattus rattus

The effect of the warfarin LD50 on the counts of the blood cells of Norway rat, Rattus norvegicus and roof rat, Rattus rattus from Giza and Qualyobia Governorates was investigated in the laboratory. Warfarin toxication caused significantly different blood cell counts in treated rats compared to control ones. Warfarin significantly decreased the total erythrocytic count and increased the total leucocytic count of treated rats. But, it caused significant de-crease in neutrophrils, eosinophils, basophils and monocytes, but significant increase in lymphocytes. The data also showed that in survived rats, WBC count equaled the normal level or slightly exceeded it at 33/43 days post treatment

effect of the host blood on the biology of the sand fly, phlebotomus papatasi [diptera: psychodidae] under laboratory conditions

The effect of the blood of human, Guinea pig and hamster on the different biological aspects of phlebotomid sand fly, Phiebotomus papatasi under laboratory conditions of 28 +/- 2°C, 75 +/- 5% RH and a 14:10 hr. [L:D] photoperiod regime was evaluated. Man was the most preferable host followed by hamster, and then Guinea pig. Human blood gave the highest yield of eggs [mean: 65.15 eggs/female], highest hatchability [mean: 96.23%], shortest egg incubation period [mean: 7.37 days], shortest larval duration [mean: 22.59 days], shortest adult emergence period [mean: 39.73 days] and highest productivity of the adult progeny [mean; 81.75%]. As human blood can not be currently used for laboratory rearing and colonization of sand flies, the hamster may be chosen as source of a substituted blood for the long term colonization of P. papatasi

Detection of haematologic effects of mosquito biting using an animal model

The studies on haematologic changes in humans or animals as a result of mosquito bites are few. This study was undertaken to examines changes in the blood picture of mice[Mus muscu-lus] exposed to culexpipiens biting Mice exposed to mosquito bites either once twice [with7days between the two bites showed insignificantly higher [P>0.05] counts of the total blood cell, platelets and hemoglobin content than normal mice with the highest level [11%] was in WBCs following the second bite mosquito biting exerts its effects largely upon the differential WBCs. Exposure of mice once or twice to mosquito bites resul- ted in increased numbers of the 5 WBC types.compared to control mice cells, the highest [P < 0.01] levels of basophils [7.19-fold, 72.02 cell/ul],eosinophils [3.59-fold, 216.05 cells/ul], monocytes [1.34-fold, 288.08 cells/ul and lymphocytes [1.29-fold, 1833.74 cells/ul] were after the second bite. Segmented neutrophils significantly [p < 0.01] decreased by 2% and 5%of the normal mice count following first and second bite, respectively

Immunomodulatory properties of sand fly Saliva and its role on vertebrate host

The salivary glands of Phlebotomus papatasi and P. langeroni were investigated for their immunomodulatory properties on vertebrate hosts. Laboratory reared sand fly, were used for feeding on hamsters and for extraction of salivary gland. To determine the influence of the sand fly saliva homogenate [SGH] were performed ELISA using sera from injected hamsters by SGH. Frequent feeding of P. papatasi on hamsters were carried out to relate the antibody titre with the biting rate. The mosquito Culex pipiens was allowed to feed on pre-exposed hamsters to P. papatasi bites. Antibodies correlated with the saliva of both species showed low titre and not related either to the time [after feeding and injection] or to the number of fed flies. Saliva of P. langeroni [non vector] recorded higher anti-body titre than P. papatasi. The preliminary experiment of the mosquitoes' feeding [C. pipiens] on pre-exposed hamsters on its saliva showed cross reactions between biting of mosquitoes and sand-flies. More investigations are needed to study the effects of sand fly saliva on human immune responses to evaluate the fly salivary proteins as vaccines for leishmaniasis and to prevent or decrease the sand-flies biting or probably mosquitoes