Where the Zika virus is most likely to occur in the United States.

Scientists who use computer models to predict future events are often wrong.
, a recent article in the journal Science announced that some modelers appear to have made the right prediction: a team of meteorologists and entomologists in May predicted where the Zika virus is most likely to be in the United States.
, the only cases of mosquito-borne Zika virus to humans in the U.S. mainland have occurred in southern Florida and Brownsville, Texas.
this is in line with the best model for Zika virus transmission.
and if history repeats itself, cold weather will reduce the number of the Aedes aegypti mosquito, the main vector of the Zika virus, when winter arrives, and the spread may stop and re-emerge later in the spring.
so far, the Zika virus has only appeared on a small scale in the United States, much to the relief of public health officials who are close to the enemy.
and the modelers have confidence that their "crystal ball" does work.
Monaghan, a model designer at the National Center for Atmospheric Research in Colorado, said his team has not updated the Zika virus forecast, but noted that the zika virus may be spreading in the U.S. this year at the same location as the current dengue virus.
" as a result, in addition to the continued high risk of Zika virus transmission in Brownsville and Miami, the risk of transmission in central Florida, the Florida Keys, and the Rio Grand Canyon on the South Texas border will increase in 2017.
," Monaghan said.
but Monaghan stressed that he could make mistakes.
systems are so complex that it is always difficult to predict the spread of viruses.
," he said.
three is the story of what happened in May this year, showing how model designers think: If history repeats itself, the U.S. media will be in a state of uproar over the country's first confirmed case of Zika virus transmission from mosquitoes to humans.
"local" transmission has not occurred so far, but scientists believe it is likely to occur in the coming weeks.
look at the attention caused by foreign cases of the Zika virus, we know that if this happens, the U.S. media will be full of firepower.
, politics will add fuel to the fire: White House Press Secretary Josh Earnest has released a map in his daily briefing showing that the Zika virus will sweep across half of the continental United States by the middle of the summer.
map behind me shows that Congress needs to act immediately.
," Earnest said, urging Congress to approve Barack ObamaPresident Ma plan to allocate $1.9 billion in emergency aid to fight the Zika virus.
the Zika virus and its mosquito-borne transmission say the U.S. is still calm.
they predict that the virus, which can harm fetuses, will spread locally in only a small area of the U.S. mainland, a narrow stretch of land stretching from Florida along the Gulf Coast to Texas.
, mosquito-induced diseases spread in the United States and in Latin America before local transmission.
on the other hand, the Zika virus has many unsolly mysteries, especially how it works in pregnant women, how to miscarry some pregnant women, and how others give birth to babies with brain dysfunctions such as glyphs.
The mosquito-free mode of transmission of the Zika virus is also a problem: the virus can survive in sperm and is sexually transmitted;
, however, there is a good understanding of the type of mosquitoes that the Zika virus hosts and the patterns of its transmission to humans.
two diseases transmitted by the same type of mosquito, dengue fever and Chekungunya fever, have also been used by scientists.
U.S. does not have the conditions for an outbreak of the Zika virus spreading locally in Latin America, said Thomas Scott, an entomologist and epidemiologist at the University of California, Davis.
, "Of course, I don't want to exaggerate and give the impression that you don't need to worry."
, who knows how things are going to go? "I don't think the Zika virus is going to continue to spread in the U.S., mainly because we have different lifestyles and there are not as many mosquitoes in the U.S.
carrier of the Zika virus is the temperature-sensitive Aedes aegypti mosquito.
only exist in small parts of the United States and multiply in large numbers during the summer months when temperatures reach 25 to 32 degrees Celsius.
brazil alone, there were about 1.3 million infections in 2015 because of the large number of Aedes aegypti mosquitoes.
and people's skin exposure is high because of the hot weather, and Brazilians prefer to wear vests, slippers and shorts.
poverty is one of the reasons the Zika virus is rampant in Latin America.
In many parts of the country, people don't install screens and windows, and usually there are tubes or pots in the dark, filled with non-flowing water, which are used as breeding grounds by the Aedes aegypti mosquito, known as the "cockroach" of mosquitoes.
, "this mosquito doesn't fly very far after birth."
usually carry viruses around in humans.
," Says Scott, Latin America's social culture has also contributed to the spread of the virus: "In many places where the Zika virus is rampant, people are happy to travel around cities to visit friends and relatives.
, he says, and in the United States, "people usually stay in air-conditioned rooms and watch TV as soon as they get home."
" Scott recently participated in a global Zika virus modeling project led by Simon Hay, head of geospatial science at the Institute for Health Measurement and Evaluation in Seattle, Washington.
based on factors such as annual rainfall, temperature, Aedes aegypti mosquito distribution, and regional conditions in areas where the Zika virus is already emerging, the team mapped the virus's environmental adaptability.
also collected information about the Aedes aegypti mosquito, which can also be a carrier of the Zika virus.
the United States, the Aedes aegypti mosquito is more widespread than the Aedes aegypti mosquito.
But Scott doubts it will be able to maintain the chain of transmission, because unlike the Aedes aegypti mosquito, which sucks human blood only for appetizers, it will then go to other animals to complete the blood-sucking meal.
" nuances in the frequency of host bites can make a big difference to the results of virus transmission.
," Scott said.
model, published online on eLIFE, calculates that 2.17 billion people around the world live in environments suitable for the survival of the Zika virus.
high-risk regions include more than half of Latin America, South-East Asia, northern Australia, and the vast African region near the equator.
but the risk of transmission of the Zika virus in the United States is limited.
"high-risk" areas include Florida and the coastlines of Alabama, Mississippi, Louisiana and Texas to the west.
the white house press briefing above is from another article published March 16 in the Public Library of Science - Current Outbreaks.
The White House presents it as a "month-to-month distribution of mosquitoes capable of carrying the Zika virus", so it looks like a wave of yellow, orange and red circles expanding on the U.S. map over time in 2016.
the paper, these data, based on climate data, point to the "potential range" of mosquito populations, i.e. how large mosquito populations may be in these areas.
could be far beyond what is currently known about the mosquito's actual life.
map extends northwards to places like Denver and Salt Lake City, where the Aedes aegypti mosquito has never appeared.
"I don't have any clear assessment of the White House's use of this map."
," said Andrew Monaghan, a meteorologist at the National Center for Atmospheric Research in Colorado and head of the mapping team.
monaghan stressed, "We did this map primarily to show the seasonal climate adaptability of the Aedes aegypti mosquito, not to indicate the precise distribution of the mosquito."
" Monaghan and colleagues from NASA and North Carolina State University in Raleigh agree that the area with the greatest abundance of the Aedes aegypti mosquito extends from Florida to the Gulf Coast of Texas.
map also points to another variable that could exacerbate local transmission: the number of visitors to the United States from Latin American and Caribbean countries where the Zika virus is currently endetroly transmitted.
history repeats itself, the Zika virus is only likely to begin spreading in these parts of the U.S. mainland.
first case of dengue fever on U.S. soil dates back to Philadelphia, Pennsylvania, in 1780, but local transmission stopped in 1945.
1980, dengue fever re-emerged in Texas, and a 5-year-old girl was infected.
1986, the state recorded nine more local infections, four of them in Brownsville;
2001-2002, Hawaii identified 122 cases of dengue fever, but not the Aedes aegypti mosquito, but the Aedes aegypti mosquito.
first local transmission of dengue fever was detected in Florida between 2009 and 2010, when the U.S. Department of Health cleared 88 cases related to Key West in the southern part of the state.
, there have been other sporadic cases of local transmission in the southern and central United States, the most serious of which was in 2013, when 28 people were infected.
, Chekungunya fever has so far not been a serious problem in the United States.
first confirmed case of local transmission occurred in Miami-Dade County, Florida, in 2014.
year, the CDC reported only 10 cases since then, all in South Florida counties.
January 14 last year, another map published in The Lancet also concluded that South Florida is the main breeding ground for the Zika virus.
researchers analyzed travelers arriving in the United States from certain airports in Brazil, within 50 kilometers of areas where the Zika virus is likely to spread throughout the year.
also highlighted the two Aedes aegypti mosquito-borne areas in the U.S. that are best suited to spreading the Zika virus.
found that Miami and Orlando airports are the most vulnerable to the Zika virus.
, U.S. epidemiologist D.A. Henderson noted that the threat of the Zika virus to the United States does not need to raise current fears and concerns.
, however, he fully supports the upgrading of mosquito control measures, stressing that the virus rarely causes illness in most of the people it infects and is not easily transmitted from person to person.
"We don't think there will be a large-scale infectious disease."
," he said.
Henderson is 87 years old and has seen many infectious diseases die out.
said the current U.S. media "bombing" of the Zika virus is partly due to the lack of research on the virus in the laboratory.
" is well-intentioned, but they do tend to say 'this issue should be taken seriously' in order to maintain their access to research funding.
" Henderson said, "it's not evil, and I don't want virologists to be out of money, but you have to keep an eye on what all this means."
things are a little out of the question now.
"