Emerging Threat of New World Screwworm Fly Sparks Urgent Response from USDA

The New World Screwworm fly, previously eradicated in 1966, has re-emerged as a threat due to an outbreak in Mexico. The USDA has suspended imports of cattle, horses, and bison following this alarming news. If unchecked, the NWS could significantly impact livestock and public health, echoing economic losses experienced in previous decades. Strong prevention measures are now essential to mitigate the risks of resurgence.

The re-emergence of the New World Screwworm (NWS) fly poses significant risks to U.S. livestock, particularly cattle. Previously believed eradicated in 1966, an outbreak in Mexico has raised alarms among agricultural officials, leading to immediate actions by the U.S. Department of Agriculture (USDA). Secretary Brooke Rollins declared the suspension of cattle, horse, and bison imports at southern border entry points due to this threat.

In her announcement, Rollins underscored the severity of the situation, stating, “The last time this devastating pest invaded America, it took 30 years for our cattle industry to recover. This cannot happen again.” The New World Screwworm is primarily found in areas of the Caribbean and parts of South America, including countries like Cuba and the Dominican Republic.

The NWS fly has a particularly troubling reproductive behavior. Adult females choose warm-blooded animals, such as cattle and horses, to lay their eggs in wounds or orifices. When the eggs hatch, the maggots burrow into the flesh, potentially causing deadly infestations. According to the USDA’s Animal and Plant Health Inspection Service (APHIS), these maggots cause significant damage to the host animal’s tissue with the help of sharp mouth hooks, which exacerbates the wounds and attracts more flies.

In rare occurrences, these larvae can also infest humans, leading to myiasis—a serious parasitic infection. The Centers for Disease Control and Prevention (CDC) points out that anyone traveling to infected regions, spending time with livestock, or having open wounds may be at greater risk. Infestations can result from even small wounds, like a tick bite. Vulnerable groups, such as the immunocompromised, elderly, or malnourished, face increased danger of infection, especially if they have recently undergone surgery.

Should an outbreak occur on U.S. soil, the potential fallout is vast. The USDA warns that pets, livestock, and even humans might face severe health risks. Historical evidence indicates that the southwestern U.S. suffered losses ranging from $50 million to $100 million annually during the NWS’s previous presence in the region. A report attributed higher losses in this area to considerable livestock populations, expansive geography, and an increased likelihood of the screwworm surviving winter.

Notably, even after the eradication of NWS in 1966, a localized outbreak occurred in 2016 within the Florida Keys, affecting endangered deer. However, it was swiftly eradicated by March 2017. The potential for NWS to regain a foothold in the U.S. continues to be a pressing concern for health officials and ranchers alike. The recent measures taken by the USDA reflect an urgent response to a potentially dire situation.

The New World Screwworm fly’s resurgence poses serious health and economic risks to both livestock and human populations in the U.S. with prevention measures now critical. The USDA’s suspension of imports illustrates the urgency of the situation and highlights the potential consequences, as seen in historical losses tied to prior infestations. With vulnerable populations more at risk, further actions are needed to prevent another outbreak and protect national health and agriculture.

Original Source: www.foxnews.com