A virus that starts off like the common cold could be responsible for leaving more than 100 children with paralysis . Last summer , more than 1,000 children and teens across the country were hospitalized with symptoms that appeared to be caused by a particularly nasty strain of enterovirus . While some of the children showed only minor symptoms of the virus - such as runny nose , sneezing and coughing - others suffered weakness of the limbs to complete paralysis . Doctors caring for the sick children connected the illness early on to a pathogen called enterovirus D-68 . A new study published on Monday has strengthened the connection between enterovirus D68 and the sudden paralysis of more than 100 children in the last year . A new study published Monday in the journal Lancet Infectious Diseases backed those initial opinions , after following the progress of 25 children in California and Colorado who experienced paralysis . Enteroviruses are a type of virus that use a single strand of RNA to replicate themselves inside the cells of mammals . Among other enteroviruses are polio , the virus that causes Hand Foot and Mouth disease along with others that cause a range of respiratory illnesses . Enterovirus D-68 is among the most recently idenfitied and was first spotted in California in 1962 . It can cause mild to severe respiratory illness and is likely to be spread by inhaling virus particles when an infected person coughs , sneezes , or touches a surface . In previous years only small numbers of EV-D68 infections have been reported but that has increased during 2014 , according to the US Centre for Disease Control and Prevention . It has caused severe illness in a number of children and has even been implicated in some deaths . The incidence of infections has fallen off considerably since October but public health officials warn that infections seem to spike during the late summer and autumn . Researchers now suggest that the children were infected with a mutated form of D-68 , which first appeared four years ago . B1 has five to six coding differences that make it different from other strains commonly found in the U.S. , and that these differences cause nerve-damaging symptoms similar to polio . And like polio , the nerve damage appears to be permanent - since none of the children have fully recovered . 'This is starting to look more like polio unfortunately where the paralysis appears to be permanent or semi-permanent . This is why there is such an urgency for more research to investigate this ' researcher Charles Chiu , an associate professor at the University of California , San Francisco , said according to the Washington Post . However , the study has not definitely proved the connection between B1 and the paralyzed children , since researchers could not find the strain in the patients ' spinal fluid . The researchers however , theorized that that was because the samples were taken too late . 'This is a virus that causes the common cold , ' Chiu told NBC News . 'Parents do n't bring their kids in until they are really sick . By that time , typically , the viral levels may be very , very low or undetectable . ' They looked for other viruses , bacteria , fungi and parasites that also could have caused the symptoms but none were present . Researchers were also not able to answer another mystery of the enterovirus - why some children only came down with minor symptoms and others lasting paralysis . Included in the study were two siblings that both came down with an 100 per cent genetically-identical strain of the virus in the past year . One of the siblings experienced paralysis while the other only suffered upper respiratory symptoms . With enterovirus season just a few months away in late summer , researchers are saying it 's extremely important that more work be done to unravel the B1 mystery and make grounds to develop a vaccine to fight the dangerous virus . The Children 's Hospital Colorado continues to monitor the patients infected with enterovirus , and have even set up a special clinic for the victims .
Researchers now believe mutated strain of enterovirus D-68 caused more than 100 children to suffer sudden paralysis in the last year . The B1 strain first popped up four years ago and has coding differences that make it similar to polio . None of the children monitored in the new study have fully recovered - suggesting the paralysis is permanent .