A study published in the journal in May this year Clinical infections People who have had dengue fever in the past have suggested that if they are infected with the new coronavirus, they are twice as likely to develop the symptoms of COVID-19.
The results of this study are based on the analysis of blood samples from 1,285 inhabitants of Mansiorima, a small town in the state of Acre, which is part of the Amazon region of Brazil. The main researcher was Marcelo Urbano Ferreira, a professor at the Institute of Biomedical Sciences (ICB-USP) at the University of Sao Paulo, Brazil. This study was supported by FAPESP.
“Our results show that the population most exposed to dengue fever is the one with the highest risk of getting sick when infected with SARS-CoV-2, probably due to socio-demographic factors. This is an example of what is called Syndemic. [ synergic interaction between two epidemic diseases so that one exacerbates the effects of the other ].. On the one hand, COVID-19 has hampered efforts to control dengue fever. The latter, on the other hand, seems to increase the risk for those who contract the former. “
Ferreira has been studying in Mansiorima for seven years with the goal of fighting malaria. In 2018, he began working on a project to survey 20% of the town’s population every six months. His team calls home, applies questionnaires, and collects blood samples. In early 2020, the project was additionally funded by FAPESP and was able to direct some of its research efforts to monitoring and characterization of SARS-CoV-2 in the region.
"In September 2020, another group study was published, suggesting that areas with high cases of dengue are relatively less susceptible to COVID-19. Since blood samples had already been collected from residents of Mansiorima before and after the first wave of the pandemic, this material was used to hypothesize that previous infection with the dengue virus provided some protection against SARS-CoV-2. I decided to verify. What we found was the exact opposite. “
Marcelo Urbano Ferreira, Professor, Institute of Biomedical Sciences, University of Sao Paulo, Brazil
This study was supported by FAPESP.
The analyzed blood samples were collected in November 2019 and November 2020. These were submitted to tests that could detect antibodies against all four dengue serotypes and SARS-CoV-2.
The results showed that 37% of the cohorts surveyed were infected with dengue fever before November 2019 and 35% were infected with the new coronavirus by November 2020. Clinical data (symptoms and outcomes) of volunteers diagnosed with COVID-19 were also analyzed.
“We have developed a statistical analysis to conclude that previous infections with the dengue virus do not change the risk of being infected with SARS-CoV-2, while our study also shows that people with dengue have symptoms. It shows that they are likely to be infected with SARS-CoV-2, “said Vanessa Nicolete, the first author of the article. Nicolete is a postdoctoral researcher at ICB-USP.
The cause of the phenomenon described in the article is unknown. There may be biological evidence in the sense that antibodies to the dengue virus somehow exacerbate COVID-19. Alternatively, it may be due to sociodemographic factors that make a particular population more vulnerable to both diseases for a variety of reasons.
“This result demonstrates the importance of strengthening both social distance measures introduced to control the spread of SARS-CoV-2 and efforts to control dengue vectors. Two epidemics are at the same time. It’s happening and affecting the same vulnerable population, which should get more attention from the federal government. “
Nicolete, VC, et al.. (2021) Amazon’s Interacting Epidemic in Brazil: Previous Dengue Infections Associated with Increased Risk of COVID-19 in Population-Based Cohort Studies.. Clinical infection. Doi.
Previous dengue infection significantly increases the risk of symptomatological COVID-19
Source link Previous dengue infection significantly increases the risk of symptomatological COVID-19