Miami's Zika Virus Woes Are Far From Over

On October 19, the Centers for Disease Control and Prevention (CDC) issued updated guidance on the mosquito-borne virus in the city of Miami after a new case cluster emerged in the “Little Haiti” neighborhood. After relaxing travel warnings to the city’s Wynwood neighborhood in early September, when an ongoing outbreak there that had resulted in more than 80 Zika cases, was deemed over—thanks to the use of pesticides to control the local mosquito population—the CDC announced new warnings for Little Haiti. The Florida Department of Health (DOH) announced that there was a new case cluster of the virus, linked to local mosquitos. More than 180 cases of Zika in Florida have been traced to bites sustained from mosquitos in South Florida.

“[CDC] continues to work with Florida health officials to investigate new cases of locally transmitted Zika virus infection in Miami-Dade County, Florida,” the agency said in a statement. “The Florida [DOH identified last week an additional area where local, state, and CDC officials have determined that the intensity of Zika virus transmission presents a significant risk to pregnant women.”

According to officials, the affected neighborhood occupies a 1-square mile area of Miami-Dade County, between Northwest 79th Street to the north, Northwest 63rd Street to the south, Northwest 10th Avenue to the west and North Miami Avenue to the east. The CDC is now advising pregnant women traveling to this area to use “protective measures to prevent exposure to Zika,” and recommending that pregnant women who have “lived in, traveled to, or had unprotected sex with someone who lived in or traveled to any area of Miami-Dade County” get tested for Zika virus.

At present, the CDC designates areas of Zika active transmission as “red” and “cautionary areas” as “yellow.” Red areas constitute regions “where local, state, and CDC officials have determined that the intensity of Zika virus transmission presents a significant risk to pregnant women… [as] determined by… geographic distribution of cases, number of cases identified, known or suspected links between cases and population density.” As of the October 19 guidance, both Little Haiti (also known as Little River) and Miami Beach have both been classified as “red” areas, while the rest of Miami-Dade County is a “yellow” area.

The CDC recommends that pregnant women consider postponing travel to “yellow” areas of Miami-Dade County, and “specifically avoid travel to “red” such as Little Haiti. The agency also advises pregnant women who have lived in, traveled to, or had unprotected sex with someone who lived in or traveled to Miami-Dade County since August 1 (or since July 14 for Miami Beach) to get tested for Zika virus. According to the agency, people who have traveled to or spent time in a red area should wait at least 8 weeks (for men) or 6 months (for women) after Zika symptom onset “before attempting conception.” Officials also recommend that men and women living in Zika-affected areas who plan to have children should consult with their physicians about the risks associated with the virus.

“Zika continues to pose a threat to pregnant women living in or traveling to Miami-Dade County,” said Lyle Petersen, MD, MPH, Director, CDC Division of Vector-Borne Diseases. “Our guidance today strengthens our travel advice and testing recommendations for pregnant women, to further prevent the spread of the infection among those most vulnerable.”

Brian P. Dunleavy is a medical writer and editor based in New York. His work has appeared in numerous healthcare-related publications. He is the former editor of Infectious Disease Special Edition.