Arboviruses, covid-19 and social vulnerability

From now on, there will be a tendency for covid-19 to invade poor communities, who live in conditions of agglomeration in precarious housing and without basic sanitation


It is urgent to adopt measures that minimize the impact of coronavirus on the poorest populations in the country

Urban health problems in Brazil are innumerable, among them, dengue and other arboviruses transmitted by mosquitoes of the genus Aedes, such as the Zika and Chikungunya fevers, stand out. These arboviruses represent chronic challenges for the country and for which public health responses have been disappointing. Dengue has afflicted Brazil since the mid-1980s, periodically causing massive epidemics, affecting millions of Brazilians, causing suffering and withdrawal from daily activities and, eventually, death. The introduction of Zika and Chikungunya in the country more recently, generated a triple burden of the disease transmitted by the same vector, deepening its social and economic impact. On the one hand, Zika, creating a generation of children with severe neurological disorders associated with microcephaly and bringing suffering and psychological disorders to several family nuclei. On the other hand, Chikungunya, showing a hitherto relatively unknown face of arboviruses, that of the chronic and disabling effects of the infection. In addition to the difficulties in coping with arboviruses, there are countless other infectious diseases such as tuberculosis, HIV/AIDS, visceral leishmaniasis, bacterial pneumonia, meningitis, leptospirosis, leprosy and seasonal influenza, which further aggravate the health situation of the populations of the Brazilian metropolises.

PhD in Public Health and Epidemiology from Harvard School of Public Health, Dr. Guilherme Werneck, highlights the chronic underfunding of the Unified Health System (SUS), worsened in recent years by the prioritization of a restrictive economic model and averse to investment in social policies. According to him, the approval of constitutional amendment no95 (known as the Constitutional Amendment to the Ceiling of Public Spending) brought even more uncertainties and bottlenecks in health financing in the country. “The result is the generation, with unprecedented speed, of a legion of highly vulnerable, impoverished people, living mostly in informality. It is in this context of social vulnerability that the Brazilian population, already living in a situation of epidemiological polarization where high loads of infectious, chronic-degenerative diseases, accidents and violence coexist, needs to deal with the pandemic of the new coronavirus (Covid-19)”, points out.

For Dr. Werneck, who is also a professor at the Institute of Social Medicine of the State University of Rio de Janeiro (UERJ) and the Institute of Studies in Collective Health at the Federal University of Rio de Janeiro (IESC/UFRJ), Covid-19 has demonstrated two clear features: it has a high dissemination capacity and a lower lethality compared to other recent coronavirus epidemics (SARS-CoV and MERS-CoV). Covid-19s lethality of around 2% has been suggested as a reason for not treating the epidemic with the proper seriousness. “However, percentages are misleading, because they can represent very different absolute numbers. The 2009 influenza A pandemic (H1N1pdm09), for example, had less lethality than that of Covid-19, but claimed between 150 thousand and 575 thousand lives in the world, even with a vaccine available”, points out the doctor. In his assessment, the great challenge presented by Covid-19 is the speed with which cases accumulate in the world, without any therapeutic measure or vaccine available. In just over three months since the outbreak in China at the end of 2019, almost 800 thousand cases and 40 thousand deaths have been recorded worldwide, and it is estimated that many cases and deaths will still occur in the coming months.

As of March 30 2020, just under 1 month since the definitive installation of the Covid-19 community transmission in the country, more than 4.5 thousand confirmed cases of the disease and 165 thousand deaths have already been registered, figures that are certainly underestimated considering the limited coverage of diagnostic tests, delay in processing and disseminating results and underreporting of deaths by Covid-19. Mathematical models estimate that the number of infections by the new coronavirus is at least 10 times higher and that at least 1 in 5 deaths from the disease is not being correctly attributed to it. “This picture still represents a transmission dynamic mostly concentrated in middle or upper-middle class populations, those who acquired the infection abroad and eventually transmitted it to their contacts. From now on, there will be a tendency for disease to invade poor communities, which live in conditions of agglomeration in precarious housing and without basic sanitation”, says Dr. Werneck, who is also vice-president of the Brazilian Association of Collective Health (Abrasco). The doctor is categorical in stating that the involvement of vast sections of vulnerable population by Covid-19 could be a real tragedy, with the collapse of health services and a substantial increase in the number of deaths.

The epidemiologist hopes that it will be possible to reverse this expectation, at least partially, with the extreme measures of social distancing that are being implemented in the main Brazilian cities, despite the visible discomfort of the national rentier businessmen and part of those who are in power today. “There is also the Unified Health System (SUS), a vilified SUS, under gradual and deliberate dismantle, but the SUS that today can provide the answer to the crisis, the SUS that is the only access to health care for the majority of the Brazilian population, the SUS that insists on resisting, our SUS, that the current crisis will make society realize its importance for guaranteeing the universal right to the health of its people, the greatest asset that a nation can have”, concludes Dr. Werneck, who is also a member of the editorial board of the Brazilian Society of Tropical Medicine (BSTM).