Mathematical Modeling of Population Dynamics of the Aedes Aegypti (Diptera: Culicidae) Mosquito with Some Climatic Variables in Villa Clara, Cuba

Opinion

Millions of people suffer from infections transmitted by arthropod vectors; among them, culicids are undoubtedly the most important in terms of hygiene and health, because they are one of the priority health problems in almost all tropical and subtropical regions. The objective of the study was to establish a forecast model among some meteorological variables for the focus of the Aedes aegypti mosquito species, during the period from 2007 to 2017 in the province of Villa Clara, Cuba. The research covered the 13 municipalities of the province, as well as the number of outbreaks reported by them in the different months of the period analyzed. Regressive Objective Modeling was used for the development of the predictive model. Likewise, the response variable was defined as: the focus for Ae. aegypti and as explanatory variables, the meteorological variables: Maximum Temperatures (TX), Average Temperatures (TM), Minimum Temperatures (TN), Maximum Relative Humidity (HRX), Average Relative Humidity (HRM), Minimum Relative Humidity (HRN), Provincial Precipitation (Prec.), Air Pressure (AP), Average Wind Speed (VMV) and Cloudiness (Cloud). The data for both variables came from the same time period (2007- 2017), and were provided by the Villa Clara Provincial Meteorological Center, which covers the four meteorological stations in the province (Santa Opinion Clara, Manicaragua, Caibarién and Sagua La Grande). Data processing was done by Pearson and t student correlations, as a test of statistical significance with the SPSS statistical package ver.13. A perfect model was obtained for each of the studied municipalities, with the combination of delays 1, 2, and 6, and the influence that the meteorological variables have in the modeling of the population dynamics of the Ae. a mosquito was demonstrated.

Emerging and re-emerging infectious diseases are one of the health problems that have raised the most interest in the different countries of the world in recent years, since many of such diseases are considered national disasters due to the high morbidity they generate, the large number of lives they take, and the cost they represent for the country from the economic point of view. They are more than just health problems, they become economic issues since they affect tourism, industry, exports, and the health sector needs to provide resources to control the disease. Millions of people suffer from infections transmitted by arthropod vectors, including culicids, which are undoubtedly the most important in terms of hygiene and health because they are one of the priority health problems in almost all tropical and subtropical regions and are responsible for the maintenance and transmission of the pathogens that cause dengue fever, yellow fever, West Nile fever, Chikungunya, Zika, Malaria, and Lymphatic Filariosis, among other deadly and debilitating infections.

In the Americas, yellow fever remains a persistent threat. Between 1985 and 2012 there were 4 066 confirmed cases of yellow fever, of which 2 351 (58%) died. Between 1980 and

2012, 150 outbreaks of yellow fever have been reported in 26 African countries, with more than 200 000 cases occurring globally. From December to February 2017, an outbreak of yellow fever affected Brazil, with 1 345 suspected cases, 295 confirmed cases, and 215 deaths. Dengue fever has spread in recent decades and continues to be the main arbovirus disease. Additionally, Chikungunya and Zika have emerged in recent years. Malaria remains the world’s leading parasitic health problem, an estimated 429 000 deaths were recorded in 2015. About 90% of malaria-related deaths globally occur in Africa, with 70% occurring in children under five years of age. This problem is now being aggravated by global warming and the intensification of extreme weather events, which have brought about changes in the behaviour of diseases and their transmitters, with the establishment of vector species in previously unrecorded locations. Weather conditions are considered to be one of the most important factors related to the spread of dengue fever outbreaks. Increases in temperature, humidity and rainfall volume are among the most influential climate variables reported.

In Cuba, the incidence of these entities, both parasitic and viral, is undoubtedly a health problem, with a tendency to increase the number of cases, as well as the populations of vector organisms. The emergence and re-emergence of arbovirus infections has increased in the last decade. The changing epidemiology and the factors responsible for the dramatic resurgence of such diseases are complex. A large percentage of human diseases are zoonotic. In addition, global and focal demographic, social and environmental changes have led to the spread of infection to humans. Seasonality and year-to-year variation in disease incidence are more marked for arboviral diseases, as vector reservoirs are susceptible to seasonal changes. Climatic conditions and the transmission dynamics of these diseases are interlinked, and since nowadays the world knows more about meteorological parameters, the impact of climate change can and should be mitigated. Over the past 50 years or more, models of emerging arbovirus diseases have changed significantly. Climate is the primary factor in determining the temporal and geographic distribution of arthropods, the characteristics of their life cycles, the consequent dispersal patterns of associated arboviruses, the evolution of arboviruses, and the efficiency with which they are transmitted from arthropods to vertebrate hosts. Although it is well known that meteorological variables are determinant in the transmission of arboviruses diseases, in our province there are few studies on the effect of some of these variables on larval densities of culicids with entomoepidemiological importance.