Avindra Nath, clinical director of the National Institute of Neurological Disorders and Stroke and president of the International Society for NeuroVirology, compared the situation to the prolonged investigations that led to confirmation of HIV as the cause of AIDS. In response to the suggestion that the enterovirus might be taking over the role of polio, Nath said that EV-D68 was far less virulent and spread much more slowly than polio, and that unlike in polio, only a few cases of paralysis were seen per thousand children infected. He also suggested that adults with respiratory diseases should also be evaluated for neurological deficits, and that infectious disease should be considered as a cause when patients presented with neurological symptoms.A subsequent report described 29 cases of EV-D68-associated AFM in Europe in 2016, noting, "these probably represent only the tip of the iceberg. "CDC sees 2018 as a record year, annual documented cases of AFM reached a record 238  nationwide. The relatively lower circulation in 2020 may reflect the use of COVID-19 pandemic infection mitigation measures. Because of the EV-D68 surge in 2022 Health Alert Network (HAN) released a notice for Healthcare providers and hospitals. The CDC warned clinicians that EV-D68 detections have continued to be high. "Sentinel surveillance sites are reporting a higher proportion of EV-D68 positivity in children who are [rhinovirus and/or enterovirus] positive compared to previous years," the agency wrote. Clinicians should be aware of "the potential for an increase in AFM cases in the upcoming weeks."
Subdural hygroma does not have internal membranes that can easily rupture like subdural haematoma, but hygroma can sometimes occur together with hemorrhage to become hematohygroma.Subdural hygromas most commonly occur when events such as head trauma, infections, or cranial surgeries happen in tandem with brain atrophy, severe dehydration, prolonged spinal drainage, or any other event that causes a decrease in intracranial pressure. This provides the basis for why subdural hygromas more commonly occur in infants and elderly; infants have compressible brains while elderly patients have a greater amount of space for fluid to accumulate due to brain atrophy from age. Signs and symptoms
Most subdural hygromas are small and clinically insignificant. A majority of patients with SDG will not experience symptoms. However, some commonly reported, but nonspecific, symptoms of SDG that have been reported include headache and  nausea. Focal neurologic deficits and seizures have also been reported but are nonspecific to SDG. Larger hygromas may cause secondary localized mass effects on the adjacent brain parenchyma, enough to cause a neurologic deficit or other symptoms. Acute subdural hygromas can be a potential neurosurgical emergency, requiring decompression. Acute hygromas are typically a result of head trauma—they are a relatively common posttraumatic lesion—but can also develop following neurosurgical procedures, and have also been associated with a variety of conditions, including dehydration in the elderly, lymphoma and connective tissue diseases. Diagnosis
In CT scan, subdural hygroma will have same density as the normal CSF. Meanwhile, in MRI, subdural hygroma will have same intensity with CSF.