[ad_1]
Public health measures to stop the spread of Covid-19 had unintended consequences in Latin America and Southeast Asia in 2020: dengue virus infections were prevented in hundreds of thousands of people. a study It was published this month in The Lancet. Research offers clues for new strategies for fighting a dangerous tropical disease it was infecting more and more people every year.
The research found a significant decrease in infections from April 2020 in many areas where dengue is spread by mosquitoes; The study estimates that there were 720,000 fewer cases of dengue fever worldwide in the first year of the pandemic, due to movement restrictions.
Epidemiologist at the London School of Hygiene and Tropical Medicine and senior author of the study, Dr. “We have found some really unexpected net benefits from Covid restrictions that will help us better fight dengue in the future,” said Oliver Brady. .
In 2019, more than 5 million people worldwide were infected with dengue fever, also known as “broken bone fever” because of the severe joint and muscle pain it caused.
Dr. Brady said at the beginning of the pandemic that he and other infectious disease researchers feared disasterAs resources are diverted to Covid-19 and other disease control measures such as mosquito spraying have been interrupted. The huge drop in dengue cases came as a happy surprise and left them eager to understand what could be causing it. They eliminated other potential factors, including environmental changes and decreases in reporting of dengue fever by public health agencies. That left only the severe deterioration in people’s movements as a plausible explanation, he said.
School closures, in particular, seem to have played a key role in reducing dengue cases. The main dengue vector, Aedes aegypti mosquitoes, are diurnal feeders. Most dengue control programs focus on spraying people’s homes to kill mosquitoes and monitoring for stagnant water that can feed them, under the assumption that transmission has occurred. “But if there was a situation where the house was really a risky place and mosquitoes were only biting the house, then you would expect stay-at-home orders to increase the risk – but we don’t see that in many countries,” he said.
The researchers do not suggest that stay-at-home orders should continue, but the emergency allowed for unexpected insight. Dr. Brady said their findings show biting at school or workplaces, which means mosquito control needs to be concentrated in public places. Dengue fever may have also fallen during stay-at-home orders because when people were infected, they were not going to places where new mosquitoes could bite them and transmit the virus to other people.
The study may prove that dengue symptoms are closely related to other mosquito-borne viruses, including Zika and chikungunya. However, Dr. Brady warned that soon-to-be dengue data for 2021 and for the post-pandemic period could bring bad news: infection rates could return to pre-Covid levels or worse if vector control programs are announced. deteriorating, immune levels may have dropped as fewer people were exposed, he said.
[ad_2]
Source link