A new Brazilian study suggests that dengue antibodies could offer immunity against COVID-19. Based on the study, regions where people had previously contracted dengue have fewer COVID-19 cases, coronavirus infection growth rates and deaths.

Led by Duke University Professor Miguel Nicolelis, the study compared the geographic distribution of coronavirus cases against dengue spread in certain areas. Using mathematical modeling, the researchers studied the link between dengue cases and coronavirus infections in Asia, Latin America, and islands in the Pacific and Indian Oceans in 2019 and 2020.

Researchers noted the significant correlations between COVID-19 incidence, infection growth rate, and deaths to the percentage of people with dengue antibodies. They described the link between COVID-19 and dengue as “highly complementary,” saying areas where several members of the population previously had dengue seem to have greater immunity against the pandemic.

“We discovered that the geographic distribution of dengue fever, amounting to more than 3.5 million cases from January 2019 to July 2020, was highly complementary to that of COVID-19,” noted the researchers. “States where a large portion of the population had contracted dengue reported lower COVID-19 cases and deaths, and took longer to reach exponential community transmission, due to slower SARS-CoV-2 infection growth rates,” they added.

Researchers also noted that such correlations were not observed for the chikungunya virus, which is also transmitted by the same mosquito vector. They noted that if the link between dengue and COVID-19 immunity is proven, then nations could use dengue vaccines to tackle the pandemic.

“This striking finding raises the intriguing possibility of immunological cross-reactivity between dengue’s Flavivirus serotypes and SARS-CoV-2,” the researchers noted. “If proven correct, this hypothesis could mean that dengue infection or immunization with an efficacious and safe dengue vaccine could produce some level of immunological protection for SARS-CoV-2 before a vaccine for SARS-CoV-2 becomes available.”

Meanwhile, Nicolelis said their findings are interesting since earlier studies showed that people with dengue antibodies could falsely test positive for coronavirus antibodies. A group of scientists from CSIR’s Indian Institute of Chemical Biology also claimed that dengue antibodies could bind with SARS-CoV-2, the virus that causes COVID-19.

COVID-19 positive Test result shows a patient is COVID-19 positive. Pixabay