Flu Shots Needed in the Southern Hemisphere

When most vacationers book their summer vacation in countries in the Southern Hemisphere, they should consider how to protect themselves from influenza. Currently, the World Health Organization (Influenza Update N° 534) is advising everyone in the 'south' to speak with a healthcare provider about immunization options.

As of July 2025, influenza positivity was elevated in countries of Tropical and Temperate South America, Southern and Eastern Africa, and South-East Asia.

The risk of exposure to the influenza virus during travel depends on the time of year and destination. In temperate regions, such as Brazil, influenza epidemics are more common from April to September in the Southern Hemisphere.

In the Northern Hemisphere, specifically in the United States, the previous flu season was notably severe, marking the worst in 15 years.

To help protect international travelers and others, CSL Seqirus recently announced that the company started shipping its differentiated portfolio of flu vaccines for the 2025-2026 season in the United States.

"During this past flu season, doctors' offices, emergency departments and hospitals across the country were filled with patients affected by the flu," said Gregg Sylvester, Chief Health Officer, CSL Seqirus, in a press release on July 10, 1025.

"We experienced the impact flu can have on our communities, our healthcare systems, and in our own homes. To make sure this doesn't happen again, vaccination is the first and most important action to help prevent flu and its potentially serious consequences."

According to the U.S. Centers for Disease Control and Prevention (CDC), it is recommended that all eligible individuals aged six months and older receive an annual influenza vaccine, especially those at an increased risk of severe influenza-related complications, such as older adults, pregnant individuals, and children under five years old.

Flu shots and other travel vaccines are offered at clinics and pharmacies in the U.S.