Recurrent Episodes of Some Mosquito-Borne Viral Diseases in Nigeria: A Systematic Review and Meta-Analysis.

Different ecological zones favor the breeding of Aedes species. The molecular epidemiology of dengue virus (DENV), yellow fever virus (YFV), and Chikungunya virus (CHIKV) was determined from outbreaks and surveillance activities in Nigeria. Twenty-eight DENV, twenty-five YFV, and two CHIKV sequences from Nigeria were retrieved from GenBank. Genotyping was performed with a genome detective typing tool. The evolutionary comparison was performed by the Maximum Likelihood method on MEGA. Chi-square was used to compare the association between the proportions of viral infections at different times. Six DENV-1 were detected in 1964, 1965, 1978, 2007, and 2018. Nineteen DENV-2 strains were reported, four belonging to sylvatic VI, one belonging to cosmopolitan II, and twelve to Asian I genotype V. DENV-2 genotype VI was detected in 1966, and genotypes II and V in 2019. All three DENV-3 were detected in 2018, while only one DENV-4 was identified in 2019. YFV was reported in 1946 and then in the 60s, 70s, 80s, 90s, 2018, and 2019 with reports to date. CHIKV is still circulating following its identification in 1964 and 1965. Recurrent episodes of dengue, Chikungunya, and yellow fever continue unabated. Vector control initiatives and immunization should be greatly sustained.

Presence and Potential Distribution of Aedes albopictus and Aedes japonicus japonicus (Diptera: Culicidae) in Slovenia.

In Slovenia, two invasive mosquito species are present, Aedes albopictus (Skuse, 1895) (Diptera: Culicidae) and Aedes japonicus (Theobald, 1901) (Diptera: Culicidae). In this study, we examined their actual distribution and suitable habitats for new colonizations. Data from survey of species presence in 2013 and 2015, bioclimatic variables and altitude were used for the construction of predictive maps. We produced various models in Maxent software and tested two bioclimatic variable sets, WorldClim and CHELSA. For the variable selection of A. albopictus modeling we used statistical and expert knowledge-based approach, whereas for A. j. japonicus we used only a statistically based approach. The best performing models for both species were chosen according to AIC score-based evaluation. In 2 yr of sampling, A. albopictus was largely confined to the western half of Slovenia, whereas A. j. japonicus spread significantly and can be considered as an established species in a large part of the country. Comparison of models with WorldClim and CHELSA variables for both species showed models with CHELSA variables as a better tool for prediction. Finally, we validated the models performance in predicting distribution of species according to collected field data. Our study confirms that both species are co-occurring and are sympatric in a large part of the country area. The tested models could be used for future prevention of invasive mosquitoes spreading in other countries with similar bioclimatic conditions.

Zika virus outbreak: an overview of the experimental therapeutics and treatment.

Zika virus (ZIKV) infection is a new emerging threat around the globe which might be responsible for microcephaly and Guillain-Barre syndrome in the infants. Recently, ZIKV outbreak has caused a public health crisis in Brazil after being linked to a sharp increase in birth defects. ZIKV is ssRNA virus belongs to the family Flaviviridae. It is mainly transmitted by mosquito bite specifically Aedes species and disease symptoms include fever, joint pain, muscle pain, rash, conjunctivitis, and headache. The reservoir of ZIKV is still not known. Protection at personal level by avoiding mosquito bite would help to reduce the incidence of the disease. Control of ZIKV infection by vaccination or antiviral drug either from modern, complementary and alternative medicines may be considered to be one of the most effective strategies in the long run. Large scale immunization of susceptible human population is highly required to prevent this deadly disease. Attempts should be made as soon as possible to develop effective vaccines or antiviral to prevent ZIKV infection. This article provides a current overview of the experimental therapeutics and treatment options based on modern, complementary and alternative medicines.

Study on the correlation of premises condition index and the presence of larvae of aedes species mosquitoes in human dwellings of the cuddalore district of Tamil Nadu, India.

CONCLUSIONS: It is concluded that this study helps in conducting rapid survey to identify the presence of Aedes larvae with a minimum number of staff for both inspection and treatment of Aedes larvae during the epidemic situation. OBJECTIVES: To predict dwellings for the presence of Aedes larvae rapidly based on Premises Condition Index (PCI) factors, we studied the possible presence of Aedes species mosquitoes larvae among houses in the Chidambaram urban of Cuddalore District in Tamil Nadu, India based on the scores of variables in PCI, namely House, Yard and degree of shadow. Data of these variables were collected in September and October 2006 from 1813 houses in the Chidambaram urban area during the intensive vector control activities employed for the prevention and control of Chikungunya. METHODS: The association between presence of larvae and the variables of PCI was tested by Chi-square and Correlation. The predictability of the presence of Aedes larvae based on PCI factors was computed by logistic regression. RESULTS: The study shows 301 containers in 132 houses were found positive with Aedes species out of 1813 houses surveyed. It was further observed that the probability of presence of positive premises was four times higher in the premises with 75% shadow compared with premises with a 25% shadow. These findings showed a significant association (p < 0.001) with positive premises.

Evaluation of the efficacy of cynoff 25 ULV to eradicate aedes species, dengue vectors in Vietnam, 2004

Background: Dengue fever remains a major public health problem in Vietnam. It was transmitted through two main Aedes species, namely Aedes aegypti and Aedes albopictus in which Aedes aegypti played the predominant role in transmitting the dengue viruses (accounted for 94% of the Aedes genus).Different groups of insecticides have been widely used in the community. As a consequence, it increased the resistance level of Aedes vectors to the insecticides. Therefore, a new synthesized insecticide was required for future control and prevention of dengue epidemics. \r\n', u'Objectives: To evaluate the efficacy of Cynoff 25 ULV in suppressing Aedes species in Vietnam. \r\n', u'Subjects and methods: The study was conducted in the entomology laboratory and in the fields of Ha Tay province. ULV spraying was implemented in Hiengiang commune, Thuongtin district, in comparison with a control area, Van Mo commune in Ha Dong town.\r\n', u'Results and conclusions: : Cynoff 25 ULV had a high efficacy that kills over 90% of 2 dengue vector species, namely Aedes aegypti and Aedes albopicctus after 24 hours exposure at the distance of 30 meters from the brass nozzle of a STIHL SR 400 sprayer. In the field trials, Cynoff 25 ULV also had high efficacy in killing Aedes species, e.g. 100% of Aedes species were killed after spraying and the effects lasted for 3 months for Aedes aegypti and one month for Aedes albopictus species. The insecticide had no side-effects or any other adverse effects to humans, livestock and the environment in the intervention areas. \r\n', u'