Scenarios for the Spread of COVID-19 in Manaus, Northern Brazil

Abstract

We use a compartmental model to project scenarios for the spread of COVID-19 in the city of Manaus, with different degrees of social distancing and isolation of infectious individuals. In a scenario without any containment measures, our projections point to more than 50,000 (simultaneously) infectious individuals before the end of April 2020. Only in a scenario with strict and extensive social distancing (lockdown), implemented and observed as of March 23 rd , 2020, would this number be less than 50,000 in the first half of June. Furthermore, an increase in the number of tests or in the collective awareness among the population regarding the importance of strict distancing measures would have only had a significant impact if implemented before the end of March.

Misinformation Caused Increased Urban Mobility and the End of Social Confinement Before the Second Wave of COVID-19 in Amazonia

“…Contrary to the newsletter’s assertion that Manaus was entering the last phase of the pandemic in early June 2020, the evidence from two studies by authors of the current paper pointed to a second wave of SARS-CoV-2 infections [ 5 , 16 ]. Epidemiological data at that time suggested that no European country had seen high enough infection rates to prevent a second wave of transmission if behavioral controls or precautions were to be relaxed without compensatory measures being implemented [ 17 ].…”

Dynamics of COVID-19 in Amazonia: A history of government denialism and the risk of a third wave

“…For Brazil in general, and for Manaus in particular, elderly people usually live in the same households as their younger family members, if not in the same rooms, as is often the case in lower-income homes. Thus, in these neighborhoods, we assume high population mixing, in line with Bitar and Steinmetz (2020) . In this situation, it is much more challenging to model social-contact networks based on age-structured models.…”

“…The parameters of interest in the model are described as follows: We assume the population of Manaus to be N = 2.2 million inhabitants and consider scenarios with a population mixing value of 0.85 ( Bitar and Steinmetz, 2020 ). COVID-19′s infection fatality rate (IFR) for the population of Manaus is based on estimates of the infection fatality rate for each age group and on the age structure of the population of the Manaus city according to the Brazilian census ( IBGE, 2010 , Ioannidis, 2020 ).…”

“…We assume the population of Manaus to be N = 2.2 million inhabitants and consider scenarios with a population mixing value of 0.85 ( Bitar and Steinmetz, 2020 ).…”