Arboviral diseases and COVID-19 in Brazil: Concerns regarding climatic, sanitation, and endemic scenario.

To the Editor,

Coronavirus disease‐19 (COVID‐19) has emerged in Latin America in a different scenario from North America, Asia, and Europe. COVID‐19 was officially first described in Brazil in São Paulo, on 26th February since then, progressively, Brazil has been witnessing a massive and concerning increase on the COVID‐19 incidence curve, which threatens the Brazilian's health, economic and social conditions in many ways. We read with interest the recent commentary paper by Blasco et al, which points out the occurrence of other respiratory coinfections, considering the different periods of the year (seasons), and the possibility of a viral interference phenomenon.

Nevertheless, here we discuss and raise awareness of some difficulties that Brazil may face during the COVID‐19 pandemic, not only regarding to other respiratory pathogens, but also to other relevant issues parallelly occurring in Brazil: (a) Brazil is in the middle of the autumn season (21st March‐20th June) and winter season will end only on 22nd September. This climatic scenario provides a longer period with high transmissibility of respiratory viruses (for instance, Influenza A H1N1 and H3N2, Influenza B), parallelly.

Besides, (b) Brazil is localized in a geographical tropical area with relevant arboviral diseases. In 2019 Dengue fever presented highest incidence during March to June, mainly at Southeast and Midwest regions. Number of cases and incidence per 100 000 habitants during 2019 of dengue fever were 1 544 987 and 735, respectively, while chikungunya and zika fever presented 132 205 and 10 768 cases. In Brazil, probably it will occur overlapping curves of arboviruses and COVID‐19, which will overload our public health system.

In addition to that, (c) regarding intensive care units (ICU), there are only 22 ICU beds per 10 000 habitants and disparities exist between different Brazilian regions and public versus private health systems according last surveillance in 2020. Public health system has 14 ICU beds per 10 000 habitants, while private health system 49 ICU beds per 10 000 habitants. The North Brazilian accounts for 43% of the total ICU beds in Brazil, while Southeast accounts for more than 50%. After SARS‐CoV‐2 infection, ICU occupation rate increased progressively. São Paulo, the state most affected by COVID‐19 in Southeast region, presents 74% of ICU occupation, while São Paulo City, the capital of the state, 90% (until 24th May 2020). The North region presents same tendency than Southeast; Pará State and Amazonas State present an ICU occupation rate between 85% and 90% (until 24th May 2020). ,

Moreover, (d) until 24th May 2020, 363 211 new cases of COVID‐19 and 22 666 deaths occurred in Brazil, where Southeast region presents the highest number of cases of COVID‐19, with 131 347 cases, 10 584 deaths and an incidence of 1486 cases/100 000 habitants (mortality rate of 120 deaths/100 000 habitants). Additionally, this same region reported 1 024 548 cases of Dengue fever in 2019, which represented 66% of Brazilian total cases. An increase of 479% in dengue fever cases should be highlighted in Northwest region between September/2018‐February/2019 and September/2019‐February/2020. During all 2019, Dengue fever and chikungunya were responsible for 782 and 92 deaths, respectively. However, since severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has landed in Brazil, even during the moment of flattened curve, COVID‐19 already have exceeded the number of deaths by arboviruses in a shorter time length.

Another point that should be highlighted is the (e) difficulty found to distinguish dengue fever and COVID‐19 and its implications, which present similar laboratorial and clinical characteristics. Besides that, it has been pointed out false‐positive results in serological tests for dengue fever, which later were confirmed as COVID‐19. A major concern must be raised for the high incidence of arboviruses in peripherical areas and low‐income communities in Brazil (ie, slums), concomitant to COVID‐19 dissemination, once sanitation and hygiene measures and medical access are scarce.

It is important to raise awareness about the possible different COVID‐19 impacts in Brazilian health system when considering concomitant endemics, such as caused by arboviruses and the respiratory diseases that a high transmissibility of other respiratory viruses are linked to. These issues demand urgent attention, once infection cases and deaths caused by COVID‐19 remain underdiagnosed due to a lack of resources, and arboviruses epidemic is a reality, which may culminate in a higher SARS‐CoV‐2 dissemination in Brazil with serious and devastating impacts in the health system, public health, and social conditions.

CONFLICT OF INTERESTS

FFT is a CNPq researcher. The other authors declare that there are no conflict of interests.

AUTHOR CONTRIBUTIONS

Conceptualization: VSTR and JPT; data curation: VSTR and JPT; formal analysis: VSTR, JPT, and FFT; supervision: FFT; roles/writing‐original draft: VSTR and JPT; writing‐review and editing: VSTR, JPT, and FFT.