Polio-Like Syndrome Outbreak Prevented, Delayed By COVID-19 Social Distancing

Studies say that other than delaying and slowing down the spread of COVID-19, social distancing may have also delayed transmissions of a rare outbreak of polio-like syndrome, says Princeton University Researchers.

Despite its rarity, acute flaccid myelitis (AFM) is a scathing condition that seriously diminishes motor functions, causes weakness of the limbs, and may lead to lifelong disabilities.

What is Acute Flaccid Myelitis?

According to the Centers for Disease Control and Prevention (CDC), acute flaccid myelitis is a rare neurological condition. It primarily affects the nervous systems especially the area of the spinal cord -- the gray matter -- that causes muscles and reflexes to become weak.

An increase in acute flaccid myelitis cases has occurred in 2014, 2016, and 2018 in the US with more than 90% of cases being reported in young children.

The CDC reports that more than 90% of cases with AFM had mild respiratory symptoms and fever coinciding with viral infections like enteroviruses that are common in children, even before they develop AFM.

AFM Outbreak

A study published in the journal Science Translational Medicine entitled, "Epidemiological dynamics of enterovirus D68 in the United States and implications for acute flaccid myelitis" used epidemiological surveillance tools which led to researchers predicting an AFM outbreak in 2020.

Thankfully, due to social distancing and minimum health restrictions put in place amidst the onslaught of the COVID-19 pandemic, the spread was prevented or postponed.

Social distancing was effective in reducing occurrences of respiratory illnesses known as enterovirus 68 that researchers found to be closely linked with AFM.

The virus EV-D68 is usually found in infants and children which typically causes respiratory issues like coughs, runny noses, and sneezing. However, the definitive causes of AFM are inconclusive, and it has been associated with viral infections and past studied that have identified a link to EV-68.

Sang Woo Park, first author and a Ph.D. student at Princeton University's Department of Ecology & Evolutionary Biology explains that although it is uncommon, the syndrome has been consistently increasing in frequency with each outbreak since first noted in 2014 which makes it critically important to understand the patterns and drivers of the disease.

Researchers state that the findings underline the significance of epidemic surveillance in projecting future impacts of infectious diseases.

EV-D68 virus outbreaks have been reported every two years matching outbreak patterns of acute flaccid myelitis. To understand the correlation between AFC and EV-D68, researchers analyzed patterns of EV-D68 outbreaks with unique surveillance data acquired from BioFire Syndromic Trends--a cloud-based network for de-identified pathogens from across the globe collected in near-real time.

Findings show that EV-D68 outbreaks occurred every two years across many states, although not all. In states like Ohio, EV-D68 outbreaks revealed intricate patterns upholding the strong relation between AFM and EV-D68.

Likely, social distancing put in place to hamper the spread of COVID-19 contained AFM cases in 2020 where only 31 cases were reported compared to 153 cases in 2016 and 238 in 2018.

Park explains that thanks to minimum health standards, there were few circulations of EV-D68 in 2020 compared to what was expected. However, these findings make it even more important for the public to be prepared for what could come in 2021 and beyond.

Check out more news and information on Medicine & Health on Science Times.