Mozambique: Increasing polio cases have been reported in Tete and Zambezia provinces as of Nov. 10

Event

Authorities reported elevated poliovirus activity in Mozambique, May 18-Nov. 1, compared to zero cases in 2021 and one in 2020. Officials identified 21 polio cases, of which eight cases were wild poliovirus (WPV), and the remaining 13 cases were circulating vaccine-derived poliovirus (cVDPV). Polio cases have been reported in the provinces of Tete and Zambezia, where officials have continued implementing two rounds of oral polio vaccine (OPV) to prevent further transmission. This report represents the most recent information as of Nov. 10.

Context

The last notable polio outbreak in Mozambique was reported in 1992. During the current outbreak, the first confirmed polio case, a 12-year-old child from the Tete Province, displayed symptoms of paralysis in late March. Cases of cVDPV are a rare result of widespread vaccination using oral polio vaccine (OPV), which contains a live but weakened poliovirus strain. When a child is immunized with OPV, the weakened vaccine-virus replicates in the intestine for a limited time, leading to antibodies' development. In areas of inadequate sanitation, vaccine-virus excreted by these children can spread in the community.

Polio is highly infectious and can spread rapidly through contact with infected fecal material, such as contaminated food and water. Infections are generally mild, but one in 200 cases leads to irreversible paralysis. Among those victims, 5-10 percent die when respiratory muscles become affected. The risk of paralysis increases with age. There is no specific treatment for polio.

The risk of healthy individuals contracting polio from contaminated food or water remains negligible. Still, individuals with compromised immune systems or those suffering from long-term illness may be more susceptible.

Advice

Visit a doctor to receive a precautionary polio booster before traveling to Nigeria, as even mildly symptomatic or asymptomatic people are infectious. Practice basic food and water precautions: drink only boiled, bottled, or purified water, and ensure that food is properly prepared and served hot.