Implications of the COVID-19 pandemic in eliminating trachoma as a public health problem

Abstract

Background Progress towards elimination of trachoma as a public health problem has been substantial, but the coronavirus disease 2019 (COVID-19) pandemic has disrupted community-based control efforts. Methods We use a susceptible-infected model to estimate the impact of delayed distribution of azithromycin treatment on the prevalence of active trachoma. Results We identify three distinct scenarios for geographic districts depending on whether the basic reproduction number and the treatment-associated reproduction number are above or below a value of 1. We find that when the basic reproduction number is <1, no significant delays in disease control will be caused. However, when the basic reproduction number is >1, significant delays can occur. In most districts, 1 y of COVID-related delay can be mitigated by a single extra round of mass drug administration. However, supercritical districts require a new paradigm of infection control because the current strategies will not eliminate disease. Conclusions If the pandemic can motivate judicious, community-specific implementation of control strategies, global elimination of trachoma as a public health problem could be accelerated.

How modelling can help steer the course set by the World Health Organization 2021-2030 roadmap on neglected tropical diseases

“…This has added clout to the call for modelling in the policy arena as well as setting a high bar of best practice for the wider modelling community. Having now gained significant traction, the use of modelling in NTD policy has contributed to new intervention tools 22 , vector control strategies [23][24][25][26] , shaped policy responding to COVID-19-related programme disruptions [27][28][29][30][31][32][33][34][35] and has aided in the development of WHO guidelines 36,37 . For this positive relationship to continue, it is imperative to invest in a mutual understanding through ongoing conversation between policy-makers and modellers, to determine what kind of questions are the "right" questions, how to interpret uncertainty and what the models can and cannot be used for.…”

“…We would like to acknowledge all of those who contributed to the pieces within this collection. We list them here in alphabetical order; Fernando Abad-Franch 30,42…”

Dynamics of HSV-2 in the Presence of Optimal Counseling and Education among Prisoners

“…Equations ( 25) and ( 26) are converted into a problem of minimizing pointwise the Hamiltonian J, with respect to the control u, through the application of the Pontryagin's Maximum Principle. First, we formulate the Hamiltonian from the cost functional equation (26) and the governing dynamics equation ( 25) to obtain the optimality conditions: In addition, λ 1 , λ 2 , λ 3 , λ 4 are the respective adjoints for the states S, I, R, D. e system of adjoint equations is obtained by taking the appropriate partial derivatives of the Hamiltonian given in equation ( 29) concerning the respective state and control variables. Theorem 9.…”

“…and recalling that, the total cost associated with the infected individuals is given by equation (26). Using our baseline values from Table 1, the total cost of executing the control strategy will be J � 2.0268 × 10 4 .…”

“…Mathematical epidemiological models have been demonstrated to be vital tools that can help understand this disease and provide solutions to phenomena that are complex to measure in the field. e literature on epidemic models on the spread of infectious diseases is quite substantial and it also contains some recent research works (see [24][25][26][27][28]). In [24], a new definition of a fractional derivative with nonsingular kernel in the sense of Caputo was proposed, which generalized various forms existing in the literature.…”