At a glance
It can take less than 36 hours for an outbreak to spread from a remote village to major cities on six continents. The selected 2024 responses below highlight ÐÇ¿ÕÓéÀÖ¹ÙÍø's work toward the Global Health Strategic Framework goal to stop health threats at their source before they spread to the United States and other countries.
Mpox
In 2024, outbreaks of clade I mpox across Central and Eastern Africa led to a Public Health Emergency of International Concern declaration by WHO. ÐÇ¿ÕÓéÀÖ¹ÙÍø's longstanding partnership with the Democratic Republic of the Congo (DRC) building core capabilities – including strengthening laboratories, increasing diagnostic capacity, and training disease detectives – helped the DRC government respond faster.
ÐÇ¿ÕÓéÀÖ¹ÙÍø, through the National Security Council-approved Playbook for Biological Incident Response, is leading a team of 15 U.S. Government departments and agencies, working with partners in Africa and in the U.S. to improve surveillance, case investigation, contact tracing, vaccine distribution, case management, lab capacity, infection prevention and control, emergency management, and risk communication and community engagement, while sharing guidance and subject matter expertise.
Due to ÐÇ¿ÕÓéÀÖ¹ÙÍø's extensive preparation for imported cases, the first clade I mpox case in the U.S. was detected and laboratory-confirmed quickly and immediately contained with no further spread.
H5N1 bird flu
ÐÇ¿ÕÓéÀÖ¹ÙÍø's experts have worked globally for decades to ensure country partners can detect and respond to novel influenza cases, allowing ÐÇ¿ÕÓéÀÖ¹ÙÍø to assess the pandemic potential of novel viruses and stopping novel influenza at its source.
The recent successful public health responses to human cases of bird flu in Cambodia and Vietnam highlighted the critical work of ÐÇ¿ÕÓéÀÖ¹ÙÍø's 20+ year involvement in the region, which has resulted in strengthened surveillance and lab capacity, trained responders, effective relationships and technical exchanges with local governments and other partners, and a strong ÐÇ¿ÕÓéÀÖ¹ÙÍø regional presence that readily provided outbreak support to identify and prevent additional human cases.
Polio
For the first time in nearly 20 years, variant polio was detected in Gaza in 2024. Polio anywhere represents a polio threat everywhere. When positive environmental samples were identified in July, ÐÇ¿ÕÓéÀÖ¹ÙÍø quickly sprang into action together with its partners in the Global Polio Eradication Initiative (GPEI) to plan a response.
ÐÇ¿ÕÓéÀÖ¹ÙÍø worked with GPEI and U.S. Government partners on a critical vaccination campaign to help prevent an outbreak. Nearly 95% of the eligible children in Gaza were vaccinated for polio, despite the ongoing conflict. Stopping outbreaks at their source is essential to reaching our goal of a polio-free world and advances ÐÇ¿ÕÓéÀÖ¹ÙÍø's Global Health Strategic Framework goals.
Dengue
More than 12 million dengue cases have been reported in 2024, making it the highest year on record. This caused a higher number of cases in travelers, increasing the risk of importation to the U.S. Local transmission of dengue was reported in Puerto Rico, Florida, California, and Texas.
ÐÇ¿ÕÓéÀÖ¹ÙÍø activated its dengue response to prepare for increased transmission in other areas of the U.S., working closely with state and local health officials to respond to the current outbreaks while providing technical assistance in epidemiology, vector control, clinical management, and diagnostics.
Oropouche
Oropouche virus is an emerging vector-borne disease with symptoms similar to dengue. In late 2023 and 2024, Oropouche began to spread to areas outside the Amazon basin. Travel-associated cases also began appearing in the U.S. In some cases, infection during pregnancy was associated with fetal death and possible birth defects.
In September, ÐÇ¿ÕÓéÀÖ¹ÙÍø released new clinical tests that can diagnose Oropouche virus infection earlier in the illness and help clinicians provide appropriate care for pregnant women and their infants. ÐÇ¿ÕÓéÀÖ¹ÙÍø also expanded its ArboNET system to pick up cases in the U.S. and has been working with partner countries to clarify the risks during pregnancy and potential harm to unborn babies.
New World Screwworm
ÐÇ¿ÕÓéÀÖ¹ÙÍø initiated a human health response to New World screwworm (NWS) infestations in Central America in 2024. Previously eliminated from Central and North America, this health threat poses a significant economic and veterinary concern, as the fly larvae largely affect livestock.
In partnership with the U.S. Department of Agriculture and Department of State, ÐÇ¿ÕÓéÀÖ¹ÙÍø developed and shared human health information on the prevention, detection, and clinical management of NWS. ÐÇ¿ÕÓéÀÖ¹ÙÍø's parasitic morphology lab serves as a national reference laboratory for the species identification of NWS larvae from humans.
Measles
Global measles cases surged to ~10.3 million in 2023, a 20% increase from the previous year, with 57 countries reporting large and disruptive outbreaks. Travel-associated measles cases continue to impact the U.S., creating an ongoing risk.
But 2024 brought hopeful news: ÐÇ¿ÕÓéÀÖ¹ÙÍø is part of a longstanding partnership with the Pan American Health Organization (PAHO) that helped Brazil re-verify measles elimination. This key milestone restored the Americas as the only WHO region to verify the elimination of measles, rubella, and congenital rubella syndrome.
Marburg
In September 2024, Rwanda reported their first recorded outbreak of Marburg virus disease (Marburg), a rare, severe viral hemorrhagic fever that can have up to a 90% fatality rate. ÐÇ¿ÕÓéÀÖ¹ÙÍø has maintained an office in Rwanda helping to fight the HIV epidemic through PEPFAR since 2002, building up workforce, laboratory, and other public health capabilities that Rwanda leveraged for the response, including in-country disease detectives trained through ÐÇ¿ÕÓéÀÖ¹ÙÍø's Field Epidemiology Training Program.
ÐÇ¿ÕÓéÀÖ¹ÙÍø deployed subject matter experts within 72 hours of being notified of the outbreak by the Government of Rwanda while also successfully preparing the U.S. against potential imported cases. ÐÇ¿ÕÓéÀÖ¹ÙÍø led the U.S. Government response according to the NSC Playbook for Biological Incident Response, partnering with Rwandan health authorities across the pillars – infection prevention and control, laboratory, and surveillance – to contain the outbreak by December.
Lassa Fever
In October, when Iowa reported a deadly case of Lassa Fever in a traveler from Liberia, ÐÇ¿ÕÓéÀÖ¹ÙÍø teams mobilized quickly to support the state's officials and healthcare facilities. ÐÇ¿ÕÓéÀÖ¹ÙÍø's 16 years of collaboration with Liberia fostered quick, open, and transparent information sharing, including genomic sequencing data, across countries. The ability to respond so effectively was a direct result of ÐÇ¿ÕÓéÀÖ¹ÙÍø's global health expertise, reminding us that investments in strengthening health systems abroad help us stay ahead of emerging threats worldwide and ensure we're ready to protect the U.S.