Hospital-based sentinel surveillance for COVID-19: Clinical-epidemiological characteristics, disease cost, accuracy of diagnostic tests and therapeutic pathway

Emerging and reemerging diseases have proved to be a challenge for public health. Among the pathogens capable of causing pandemics, coronaviruses stand out (Cheng et al. 2007; Gao 2018). The coronaviridae family is composed of enveloped RNA viruses, widely distributed in the world, which can cause acute and chronic diseases in several animal species and in humans causing respiratory, gastrointestinal, hepatic and neurological disorders (Weiss and Leibowitz 2011; Chen, Liu, and Guo 2020). Most coronavirus infections in humans are self-limiting and of low severity, but these viruses have been responsible for two major epidemics in the last decade, with more than 10,000 reported deaths: Severe Acute Respiratory Syndrome [(SRAG) - severe acute respiratory syndrome coronavirus (SARS-CoV)], in 2009; and Middle East respiratory syndrome coronavirus (MERS-CoV), in 2012 (Weiss and Leibowitz 2011). Thus, these agents are recognized as important given their morbidity and mortality (Wang et al. 2020) and, therefore, their harmful social and economic effects on societies. On December 31, 2019, an outbreak of pneumonia in 27 people was recorded in Wuhan, Hubei province, China (WHO 2020b). Initially of unknown origin, the first 30 days of the epidemic caused by the "new coronavirus 2019" (nCoV-19) recorded more than 400 cases of "Coronavirus disease 2019" (COVID-19). Despite the containment measures adopted, in less than a month from the first records, cases of COVID-19 were reported in Thailand, Japan, South Korea, Vietnam, Singapore and the United States of America (Du Toit 2020; Wang et al. 2020 ). The World Health Organization (WHO) declared COVID-19 a public health emergency of international interest (ESPII) on January 30, 2020, for the sixth time in the organization's history (WHO 2020c). On March 11, 2020, after a 13-fold increase in the number of cases of the disease outside of China in two weeks, with a record of 4,291 deaths in 114 countries (average lethality coefficient of 3.64%), the organization declared the COVID as a "pandemic" - although the technical pandemic criteria had been in place a few weeks earlier. It should be noted that the pandemic status had not been declared by the WHO for more than a decade - since the H1N1 pandemic (WHO 2020a). In Brazil, the state of emergency in public health of national importance (ESPIN) was declared on February 3, 2020 (Brazil 2020c); the first confirmed case of COVID-19 was registered on February 26, 2020, in São Paulo; the viral genome sequenced on February 28, 2020 (Jaqueline Goes de Jesus et al. 2020); and on March 17, 2020, the first two deaths from the disease, also in the municipality of São Paulo (Flávia Albuquerque 2020). Until March 16, 2020, the epidemiological situation was 234 confirmed cases and 2,064 suspected cases, distributed in all regions of the country. Community transmission was declared in the states of São Paulo and Rio de Janeiro, and in the Federal District (DF) (Brazil 2020b). The importance of COVID-19, especially regarding its transmission capacity, morbidity, severity of respiratory manifestations and lethality, requires efficient preventive and therapeutic measures. However, despite its magnitude, there are still no specific antiviral therapies for this disease, with supportive care being the therapeutic measure used and social detachment being the recommended preventive measure (Brazil 2020a). An important disease control mechanism is the identification of suspicion and timely diagnosis, which has been highlighted by WHO as a necessary measure to support clinical and political decision-making (WHO 2020d). However, due to the diversity of agents that can cause illnesses with fever and respiratory symptoms; the limited number of resources (human and material), including diagnostic tests; and cultural issues that facilitate viral spread in Brazil, the diagnosis of 100% of suspected cases represents a challenge. Sentinel surveillance strategies, for other diseases and conditions, have been shown to be useful because they bring high quality data, especially in diseases that the passive surveillance system may not be able to report properly (Racloz, Griot, and Stärk 2006; WHO 2014 ) - as epidemic situations. In addition, the social and epidemiological context experienced in Brasília - wide social inequalities (BRAZIL 2017) and the prevalence of comorbidities such as smoking, diabetes and hypertension (Brazil 2019) - makes the proper monitoring of cases and their evolution imperative. From the above, the researchers believe that it is important to implant a hospital-based sentinel surveillance in a university hospital, one of the hospitals referred for cases of SARS. This surveillance will make it possible to monitor the epidemiological situation of the DF and the Integrated Development Region of the Federal District (RIDE), based on the identification and monitoring of cases, expanding the understanding of risk and protective factors that may lead to a better understanding of the pathogenesis and its short- and long-term risks, in addition to understanding the costs arising from the cohort of inpatients and making the assessment of new technologies for the rapid diagnosis of the disease.