MIAMI/SINGAPORE/KUALA, LUMPUR – Authorities in Florida said Thursday they have found the Zika virus in three groups of trapped mosquitoes in Miami Beach, the first time this has happened in the continental U.S.
The Zika-carrying mosquitoes were trapped in a touristy 1.5-sq.-mile area of Miami Beach that had been identified as a zone of active transmission of the virus, the Florida Department of Agriculture and Consumer Services said in a news release.
“This find is disappointing, but not surprising,” Commissioner of Agriculture Adam H. Putnam said. “Florida is among the best in the nation when it comes to mosquito surveillance and control, and this detection enables us to continue to effectively target our resources.”
Finding the virus in mosquitoes has been likened by the U.S. Centers for Disease Control and Prevention to finding a needle in a haystack, but the testing helps mosquito controllers target their efforts, and it confirms that the insects are indeed a mode of transmission as suspected. The illness spreads from people to mosquitoes to people again through bites, but the insects do not spread the disease among their own population, and their lifespan is just a few weeks.
Since July, authorities have linked a couple dozen cases to transmission in small areas of Miami’s Wynwood district and the popular South Beach neighborhood of Miami Beach. Other isolated cases not linked to travel outside the U.S. also have been confirmed elsewhere in Miami-Dade county, as well as in neighboring counties and in the Tampa Bay area, totaling 47 for the state.
Putnam said Miami-Dade County, the City of Miami Beach, and state and federal partners are continuing to work aggressively to prevent the spread of Zika.
The agency says Miami-Dade County’s Mosquito Control team will continue to conduct inspections to reduce mosquito breeding and perform spraying around in a 1/8-mile radius around the area where the infected batches of mosquitoes were trapped.
Officials said 95 more mosquito samples — each one containing several dozen bugs — tested negative since those three were found. Intensive trapping and testing is continuing across the region.
“As it has been from the beginning, our goal is to eliminate the cycle of transmission by eliminating the mosquitoes,” Miami-Dade County Mayor Carlos A. Gimenez said in the news release.
The Florida Department of Health has said there have so far been 47 cases of Zika in people believed to have contracted the virus in a small area of Miami, but until now, the department had not found infected mosquitoes.
Now that Zika-positive mosquitoes have been identified in surveillance traps in Miami Beach, Miami-Dade County’s Mosquito Control team will continue to conduct inspections to reduce mosquito breeding and perform spray treatments as necessary in a 1/8-mile radius around the trap location, officials said.
“We are aggressively working to eliminate any and all potential mosquito breeding grounds,” Miami Beach Mayor Philip Levine said in a statement. “We need Congress to do its part to provide the necessary emergency resources to properly combat the spread of this virus.”
The U.S. Congress has failed to reach an agreement on emergency Zika funding after President Barack Obama requested $1.9 billion for mosquito control, development of vaccines and diagnostics and other efforts to combat Zika. The CDC has said it is running out of funds to fight the virus.
The current Zika outbreak, first detected in Brazil last year, has rapidly spread across the Americas.
Florida officials said more than 40,000 mosquitoes had been tested since May, and that the three samples were the first to test positive.
“It means that there is a substantial amount of Zika virus in that population because it’s actually not easy to find the virus in the mosquitoes that you trap,” said Dr. William Schaffner, professor of medicine in the division of infectious diseases at Vanderbilt University School of Medicine in Nashville.
Zika infection in pregnant women can cause the rare birth defect known as microcephaly, which can lead to serious developmental problems, and has also been linked to severe fetal brain abnormalities.
Singapore authorities meanwhile said Thursday that a second woman has been confirmed to be infected with the Zika virus as the total number of people infected so far rose by 36 to 151.
Three of the new cases were in other parts of Singapore away from the original cluster that affected the Aljunied Crescent and Sims Drive areas in the central eastern part of Singapore.
One case in Harvey Crescent is nearer to Changi Airport.
Singapore’s cramped urban setting has made it a vulnerable target for spread of the mosquito-borne Zika virus, but the disease has proven to be mild and most of the people have recovered.
“This is a disease that spreads through the mosquito vector and obviously in urban settings like ours where people are living much closer together. In Singapore 80 percent of our residents live in apartment buildings, you have a higher concentration and high congregation of people together,” Derek Ho, director general of public health at the National Environment Agency, said in a press conference on Thursday.
“Of course it then becomes much easier for the transmission of the disease. Therefore it does have a different disease dynamics than in a Malaysian authorities also confirmed the country’s first cases of Zika virus on Thursday, saying that a 58-year old woman who had visited Singapore had become infected with the virus.
Addressing reporters, Health Minister Subramaniam Sathasivam said the woman, from Klang on the outskirts of Kuala Lumpur, had visited the city-state on Aug. 19 to help care for her daughter there, who had herself contracted Zika.
She returned three days later and on Sunday began developing a rash. She was tested for the virus on Monday, and was confirmed positive.
“The source of infection is suspected to occur in Singapore, since the patient started experiencing signs of Zika on the same day with her daughter in Singapore,” Subramaniam said.
“The patient’s husband and family members who lived in the same house with her have yet to show any symptoms of Zika infection,” he added.
Zika virus is transmitted by Aedes mosquitos, which are also responsible for spreading dengue fever, a disease that is more common in tropical Malaysia.
Patients normally exhibit symptoms such as mild fever, skin rash, conjunctivitis, muscle and joint pain and headache. The virus is also known to cause microcephaly, a condition where babies are born with small heads, or their heads stop growing after birth.
Singapore has seen a spike in new cases of Zika in recent weeks, with the number of people infected in the city-state so far jumping to 115 on Wednesday.