Pope Leo XIV continues South American tour as health officials watch measles risk

Pope Leo XIV, the 71-year-old head of the Catholic Church, is holding a mass in Santa Cruz de Succhabamba in northern Peru on Saturday as his tour of South America continues. After a helicopter flight from Chiclayo air base, he returns in the evening for a prayer meeting with the Catholic community at the shrine of Saint Toribio de Mogrovejo. The large crowds drawn by the pontiff have heightened concern among Latin American health authorities, because measles cases in the region have risen sharply this year.

Return to Chiclayo

On Friday the pope went back to Chiclayo, which he regards as his former hometown. Born in Chicago, Leo previously worked in Peru as a missionary and then a bishop, and he holds Peruvian citizenship. About 500,000 people attended his open-air mass. "What a joy it is to return to Chiclayo!" he said, thanking people for their prayers, especially for his health "during this time of trial", which he said he is overcoming with God's help.

The measles threat

From January to the end of October, 57,666 confirmed measles cases were recorded in 17 countries and territories of the Americas, almost five times the figure for the same period a year earlier. At least 81 deaths have been reported. Before the visit, the Pan American Health Organization (PAHO) rated the public health risk of measles as "very high" given the expected religious mass gatherings. The concern stems mainly from low vaccination rates, particularly in Argentina and Peru. PAHO immunization head Daniel Salas Peraza said children are missing school and being hospitalized, calling it "a very complex situation".

Measles is a highly contagious airborne viral disease that can cause severe complications and death. The World Health Organization recommends two vaccine doses for children, and at least 95% of a population must be fully vaccinated to stop community spread. According to WHO data for 2025, only Uruguay reached that level. Peru's coverage was 90% for the first dose and 82% for the second; Argentina's was 84% and 55%.

Peru has recorded almost 3,000 cases this year, the fourth highest in the Americas after Guatemala, Mexico and the United States. In the five cities on the pope's itinerary — Lima, Chiclayo, Cajamarca, Cusco and Pucallpa — 170 infections have been detected. Peruvian authorities stepped up vaccination, and by the end of September 1.2 million doses had been given since April.

In Argentina, authorities issued a warning in late October about health risks tied to the visit, with up to four million people expected in Buenos Aires province. Experts also worry about government health spending cuts. Uruguay has introduced enhanced epidemiological surveillance until 29 November.