Poliovirus has been detected in Brazil for the first time since 1989. The World Health Organization (WHO) reports that it could have piggybacked into São Paulo with a sports fan prior to the World Cup.

However, Brazilians and soccer fans alike should not panic just yet. The wild poliovirus type 1 (WPV1) was detected in sewage samples collected in March at Viracopos International Airport in São Paulo, Brazil by local health officials, according to the WHO report. An isolate of the virus was detected through routine testing of sewage waters, and there does not appear to be any evidence of transmission of WPV1 in the country; although, an epidemiological investigation has been launched to verify that the virus has not spread.

According to the US Centers of Disease Control and Prevention (CDC), the poliovirus does not spread particularly easily, as it spreads through feces. Still, even the smallest amount of fecal matter can carry the virus, and thus is a problem in less sanitary countries.

In rare cases, the poliovirus can cause permanent loss of muscle function in a person's limbs, effectively immobilizing them. The virus also primarily affects young children. Thankfully, there is a vaccination for this potentially debilitative disease.

According to Brazilian health authorities, this is the first random testing that has come back positive for polivirus since 1994. The virus was officially declared eradicated in the country before that in 1989.

Unsurprisingly, investigators have determined that this most recent positive case is the product of an imported and isolated case of the virus.

"Genetic sequencing indicated a close match with a strain of WPV1 that was recently isolated from a case of polio in Equatorial Guinea," the WHO reported. "Given the ongoing WPV1 outbreak in Equatorial Guinea, low national routine immunization coverage, and the inconsistent quality of the initial outbreak response vaccination campaigns, WHO assesses the risk of additional exportation from Equatorial Guinea as high."

According to the Global Polio Eradication Initiative, as of June 18 Equatorial Guinea has seen four confirmed cases of the virus, which have been traced to another ongoing outbreak in Cameroon. Pakistan boasts the largest outbreak this year, with 82 confirmed cases.