Modelling population dynamics based on experimental trials with genetically modified (RIDL) mosquitoes

Abstract

Recently, the RIDL-SIT technology has been field-tested for control of Aedes aegypti. The technique consists of releasing genetically modified mosquitoes carrying a "lethal gene". In 2016 the World Health Organisation (WHO) and the Pan-American Health Organization (PAHO) recommend to their constituent countries to test the new technologies proposed to control Aedes aegypti populations. However, issues concerning effectiveness and ecological impact have not been thoroughly studied so far. In order to study these issues, we develop an ecological model compatible with the information available as of 2016. It presents an interdependent dynamics of mosquito populations and food in an homogeneous setting. Mosquito populations are described in an stochastic compartmental setup in terms of reaction norms depending on the available food in the environment. The development of the model allows us to indicate some critical biological knowledge that is missing and could (should) be produced. Hybridisation levels, release numbers during and after intervention and population recovery time after the intervention as a function of intervention duration and target are calculated under different hypotheses with regard to the fitness of hybrids and compared with two field studies of actual interventions. The minimal model should serve as a basis for detailed models when the necessary information to construct them is produced. For the time being, the model shows that nature will not clean the non-lethal introgressed genes.

Stochastic model for COVID-19 in slums: interaction between biology and public policies

“…General properties of Markov jump processes are assumed to hold for this problem, in particular that events are independent of each other (although related indirectly by the dependence of the rates on the populations). These properties add up to the following two results (Feller, 1940; Durrett, 2001; Solari and Natiello, 2014; Natiello and Solari, 2017):…”

Stochastic model for COVID-19 in slums: interaction between biology and public policies

“…General properties of Markov-jump processes are assumed to hold for this problem, in particular that events are independent of each other (although related indirectly by the dependence of the rates on the populations). These properties add up to the following two results [3, 23–25]: The waiting time to the next event is exponentially distributed with rate . At the occurrence time indicated above, the probability of occurrence for event α is . …”

The optimal strategy of incompatible insect technique (IIT) using Wolbachia to control Malaria

“…Genetically modified male mosquitoes are released and eggs laid by mating with wild females die in the larval stage, which consequently leads to the reduction of mosquito population. The control effectiveness for both classical SIT and RIDL has been verified by field experiments (Evans et al 2019;Bouyer et al 2020) and has been well studied in mathematical models so that possible control strategies have been examined and suggested under various situations (Phuc et al 2007;Seirin-Lee et al 2013a,b;Natiello and Solari 2020).…”