New World Screwworm Outbreak Sparks US Livestock Import Ban

The New World Screwworm fly has resurfaced as a threat to American agriculture after an outbreak in Mexico. The USDA has suspended cattle, horse, and bison imports from southern border ports. Historical context warns of potential severe economic losses should the pests invade anew. Health risks extend to humans, with infestations causing significant pain and injury.

The re-emergence of the New World Screwworm (NWS) fly is prompting serious concerns for the health of American livestock. Once thought eradicated from the United States since 1966, it has recently been detected in Mexico, raising alarms among officials. In response, the U.S. Department of Agriculture (USDA) has halted imports of live cattle, horses, and bison originating from southern border ports, as announced by USDA Secretary Brooke Rollins on social media.

In her announcement, Rollins stressed the urgency of the situation, stating, “Due to the threat of New World Screwworm, I am announcing the suspension of live cattle, horse, and bison imports effective immediately.” She went on to highlight a troubling historical precedent, noting, “The last time this devastating pest invaded America, it took 30 years for our cattle industry to recover. This cannot happen again.”

So, what exactly is the New World Screwworm? According to the USDA’s Animal and Plant Health Inspection Service, this fly is primarily found in Cuba, Haiti, the Dominican Republic, and parts of South America. While common in forested areas, the female NWS will seek out large mammals like cattle and horses in pastures to lay her eggs. Those eggs hatch into larvae—which are basically maggots—and then these creatures burrow into the flesh of their hosts, causing severe damage.

The term “screwworm” comes from the larvae’s behavior, which is reminiscent of how screws are twisted into wood. The damage inflicted can be excruciating, as maggots use sharp mouth hooks to tear at tissues. This not only enlarges existing wounds but also invites more flies to lay eggs, creating a vicious cycle of infestation. Furthermore, there have been rare cases where larvae have inflicted myiasis on humans, resulting in parasitic infections in human tissue, as noted by the Centers for Disease Control and Prevention (CDC).

Health professionals warn that individuals traveling to known infected regions, spending time near livestock, or having open wounds are at an increased risk of infection. In particular, the CDC indicates, “Wounds as small as a tick bite may attract a female to feed.” Those who are immunocompromised, elderly, or malnourished also face heightened risk for these infestations.

The potential for a resurgence of NWS in the U.S. poses a grave threat, not just to livestock but also to pets, wildlife, and humans. As the USDA has indicated, the last major outbreak, prior to its eradication in 1966, cost livestock producers between $50 million and $100 million annually. These losses were likely exacerbated by denser livestock populations and favorable conditions for overwintering the flies.

While NWS was declared eradicated in 1966, a localized outbreak was reported in the Florida Keys in 2016, affecting vulnerable deer populations. That situation was swiftly managed and eliminated by March 2017, according to APHIS.

In light of the potential risks associated with NWS, a watchful eye is necessary to ensure that history does not repeat itself.

The resurgence of the New World Screwworm poses significant threats to livestock and, potentially, human health in the United States. Measures by the USDA to prevent the import of livestock from affected regions underscore the seriousness of the outbreak in Mexico. Historical losses from similar infestations serve as a reminder of the need for vigilance. Continued monitoring and strict regulations are crucial to prevent a similar disaster in the future.

Original Source: www.foxnews.com