The study of the influence of climatic parameters on the aggressiveness and infectivity of Anopheles s.l in North Benin is essential not only to understand the effect of climate on the dynamics of transmission but also to establish a effective and targeted control of these vectors taking into account climate variability. The study was carried out in two health zones composed of six communes of North-Benin: the health zone Kandi-Gogounou-Ségbana in the department of Alibori and the health zone Djougou-Copargo-Ouaké in the department of Donga in the aim of identifying climate variables favorable to the strong aggressiveness and infectivity of Anopheles s.l in the said zone. These data will be used to evaluate the effectiveness of the strategy for the indoor sprinkling of large scale remnant insecticides, for the reduction of malaria transmission in the beneficiary communes. Longitudinal entomological and climatic monitoring, carried out for seven months in these villages, allowed us to take into account the main climate parameters that are implicated in the transmission of malaria in North Benin. Two members of the An. gambiae complex were found in the study area. This is An. gambiae s.s. and An. funestus. On the other hand, the anopheles density increases considerably during the rainy months and this increase is related to the rainfall. This result asserts the accuracy of the work of Klinkenberg et al. (2008)  in Ghana and Okono et al. (2015)  in Cameroon where these authors showed that the anopheles density is a function of the period. Each peak or decrease in rainfall was responsible for an increase or decrease in the climate parameters recorded in the area.
On the other hand, the average rate of aggressiveness of Anopheles s.l ranges from 4 to 12 in the communes of the health zone KGS and from 5 to 30 stings per man per month in the communes of the health zone DCO depending on the urbanisation situation and the type of village of residence. This result confirms the work of Téné in 2007 in the cliff of Mbô which shows that the mean aggressiveness was higher in the plain (9.34 b/h/n) than on the plateau (5.29 b/h/n), but the entomological inoculation rate did not show such a large difference; 51.84 ib/h/y with seasonal transmission and 47.68 ib/h/y with perennial transmission, respectively. This could be explained by the drop in temperature at altitude which extended the duration of the gonotrophic cycle by one day for the 2 species. According to them, despite the lower anophelian aggressiveness at altitude, the sporozoitic index is higher at Dschang (2.47%) than at Santchou (1.52%). This higher plasmodial prevalence in the vector can be explained by the migration of populations from the lower, more malarious lowlands to the uplands.
Our work is in line with that of Rhodain and Perez  in 1985 and Tchuinkam et al., 2007  which shows that at altitude, the drop in temperature and hygrometry are at the origin of the lengthening of the gonotrophic cycle.
Climatic parameters which have mainly favored aggression are wind speed, humidity, sunshine and temperature. These works are similar of mosquitosquad  in 2018 which those the recipe for mosquito activity is heat + rainfall = humidity, and this, combined with stagnant water means the perfect soupy combination for mosquito madness The temperature and activity of mosquitoes go hand in hand with insects that thrive in humid and relatively warm environments, working best at 20°C (80°F). Once the temperature has decreased to about 20°C (60°F), they become lethargic and, below 50°C (80°F), it is difficult to operate. If it’s too hot and too dry, mosquitoes will not be as active and will not feed as usual. But once the temperature drops a little and is within the tolerable range for mosquitoes, they get more hungry and therefore bite more.
On the other hand, the anopheelian density and their infectivity increase considerably in the temporal and geographical context and this increase is related to the wind speed, the rainfall. This result confirms the work of Klinkenberg et al. (2008)  in Ghana and Okono et al. (2015)  in Cameroon where these authors showed that the anophelian density is seasonal. Each peak or decrease in rainfall was responsible for an increase or decrease in the population of An. gambiae s.l.
Student Newman Keuls (SNK) tests showed higher monthly HBR in July and August whereas lower rate was recorded in May, June, January and February. De plus, the correlation and regression analyzes identified climatic factors which led to the increase in HBR during August and October. This duration of strong anopheles aggressiveness is lower than those obtained in the municipality of Corpargo in northeastern Benin (Yadouléton et al.,, 2018) . However, the months of May, July and September are the months when populations receive more bites. In addition, research on P. falciparum infectivity shows that no infected individuals were found in the population of An. Funestus. This would probably be due to the small number of mosquitoes tested.
This study shows that the lack of access to controlled meteorological and entomological data acrossall months of the year and their quality has considerably undermined the quality of the climate and the analysis of some control indicators.
Whether or not observed increases in infectivity and aggressiveness in northern Benin during the last thirty years are associated with co-varying changes in local temperature, possibly connected to global changes in climate, has been debated for decade. Studies, using differing data sets and methodologies, produced conflicting results regarding the occurrence of temperature trends and their likelihood of being responsible, at least in part, for the increases in malaria transmission in Northern Sudan.
A time series of quality controlled daily temperature and rainfall data from northern Benin.
In order to develop a pre-alert system for Benin, not only is it essential to monitor the vulnerability of the population to increased malaria transmission, but it is also important to predict and observe weather conditions. It appears that replacement of natural swamp vegetation with agricultural crops has led to increased climatic parameters, which may be responsible for elevated malaria transmission risk in cultivated areas.