(CNN) "Everything we look at with this (Zika) virus seems to be a little scarier than we initially thought," Dr. Anne Schuchat, CDC principal deputy director, told reporters during a White House briefing on Monday.

She was joined by Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Disease at the NIH. "The more and more we learn, the more you get concerned about the scope of what this virus is doing ," he said.

Both continued to remind the public that new information about the virus is being learned every day.

They reviewed what's been learned in the two weeks since they last addressed White House reporters on the virus.

Photos: Zika virus outbreak Photos: Zika virus outbreak A pest control worker fumigates a school corridor on the eve of the annual national Primary School Evaluation Test in Kuala Lumpur on Sunday, September 4. Malaysia reported its first locally transmitted Zika case on September 3. Hide Caption 1 of 29 Photos: Zika virus outbreak A banner about Zika virus is seen as ferry passengers arriving from Singapore get in line at the immigration check on September 4, in Batam, Indonesia. Hide Caption 2 of 29 Photos: Zika virus outbreak A banner is flown over the South Pointe Park area, Tuesday, September 6, in Miami Beach, Florida. Hide Caption 3 of 29 Photos: Zika virus outbreak A pest control worker fumigates drains at a local housing estate where the latest case of Zika infections were reported on Thursday, September 1, in Singapore. Hide Caption 4 of 29 Photos: Zika virus outbreak Florida Gov. Rick Scott and Florida Surgeon General Dr. Celeste Philip address the media gathered at the Miami-Dade County Department of Health as they announce five cases of Zika in a 1.5 mile area of Miami Beach on Friday, August 19, in Miami, Florida. Hide Caption 5 of 29 Photos: Zika virus outbreak Brazil's interim President Michel Temer, center right, meets with officials during Temer's first visit to the Olympic Park on Thursday, June 14, in Rio de Janeiro. The Rio 2016 Olympic Games commence August 5 amid a political and economic crisis in the country along with the Zika virus outbreak. Hide Caption 6 of 29 Photos: Zika virus outbreak Rio 2016 Chief Medical Officer Joao Grangeiro, Municipal Secretary of Health Daniel Soranz and Sub-secretary of the State for Health and Surveillence Alexandre Chieppe field questions from the media during an International Media Briefing to address the Zika virus on Tuesday, June 7, in Rio de Janeiro. Hide Caption 7 of 29 Photos: Zika virus outbreak A health worker fumigates an area in Gama, Brazil, to combat the Aedes aegypti mosquito on Wednesday, February 17. The mosquito carries the Zika virus, which has suspected links to birth defects in newborn children. The World Health Organization expects the Zika outbreak to spread to almost every country in the Americas. Hide Caption 8 of 29 Photos: Zika virus outbreak A man places a mosquito net over a bed at a home for the elderly in Masaya, Nicaragua, on Thursday, February 11. Hide Caption 9 of 29 Photos: Zika virus outbreak An Aedes aegypti mosquito floats in stagnant water inside a tire at a used tire store in Villavicencio, Colombia, on Thursday, February 4. Hide Caption 10 of 29 Photos: Zika virus outbreak A health worker fumigates an area in Caracas, Venezuela, on Tuesday, February 2. Hide Caption 11 of 29 Photos: Zika virus outbreak A lab worker exposes his arm to Aedes aegypti mosquitoes during testing at the Roosevelt Hospital in Guatemala City, Guatemala, on Monday, February 1. Hide Caption 12 of 29 Photos: Zika virus outbreak Tainara Lourenco sits inside her home in Recife, Brazil, on Friday, January 29. Lourenco, five months pregnant, lives at the epicenter of Brazil's Zika outbreak. The Zika virus has been linked to microcephaly, a neurological disorder that results in newborns with small heads and abnormal brain development. Hide Caption 13 of 29 Photos: Zika virus outbreak Dr. Angela Rocha shows brain scans of a baby born with microcephaly at the Oswaldo Cruz Hospital in Recife on Thursday, January 28. Hide Caption 14 of 29 Photos: Zika virus outbreak Alice Vitoria Gomes Bezerra, a 3-month-old baby with microcephaly, is placed in her crib by her father Wednesday, January 27, in Recife. Hide Caption 15 of 29 Photos: Zika virus outbreak A health ministry employee fumigates a home in Soyapango, El Salvador, on January 27. Hide Caption 16 of 29 Photos: Zika virus outbreak A lab technician at the Oswaldo Cruz Foundation Institute stores Aedes aegypti mosquitoes to be used in research in Recife on January 27. Hide Caption 17 of 29 Photos: Zika virus outbreak A patient suffering from Guillain-Barre syndrome recovers at a hospital in San Salvador, El Salvador, on January 27. Researchers are looking into a possible link between Zika and Guillain-Barre, a rare disorder that causes the body's immune system to attack its nerves. Hide Caption 18 of 29 Photos: Zika virus outbreak Luiz Felipe lives in Recife and is one of more than 4,000 babies in Brazil born with microcephaly since October. The drought-stricken impoverished state of Pernambuco has been the hardest-hit, registering 33% of recent cases. Hide Caption 19 of 29 Photos: Zika virus outbreak A health worker sprays insecticide under the bleachers of Rio de Janeiro's Sambadrome on Tuesday, January 26. Hide Caption 20 of 29 Photos: Zika virus outbreak A Brazilian soldier inspects a home in Recife on Monday, January 25, while canvassing the neighborhood and attempting to eradicate the larvae of mosquitoes linked to the virus. Hide Caption 21 of 29 Photos: Zika virus outbreak David Henrique Ferreira, a 5-month-old who has microcephaly, is watched by his brother in Recife on January 25. Hide Caption 22 of 29 Photos: Zika virus outbreak The larvae of Aedes aegypti mosquitoes are photographed in a lab in Cali, Colombia, on January 25. Scientists are studying the mosquitoes to control their reproduction and resistance to insecticides. Hide Caption 23 of 29 Photos: Zika virus outbreak Angelica Prato, a pregnant woman infected by the Zika virus, receives medical attention at a hospital in Cucuta, Colombia, on January 25. Hide Caption 24 of 29 Photos: Zika virus outbreak A woman walks through fumes as health ministry employees fumigate an area in Soyapango on Thursday, January 21. Hide Caption 25 of 29 Photos: Zika virus outbreak Brazilian soldiers apply insect repellent as they prepare for a cleanup operation in Sao Paulo on Wednesday, January 20. Hide Caption 26 of 29 Photos: Zika virus outbreak A researcher at the University of Sao Paulo holds a container with female Aedes aegypti mosquitoes on Monday, January 18. Hide Caption 27 of 29 Photos: Zika virus outbreak A graveyard in Lima, Peru, is fumigated on Friday, January 15. Hide Caption 28 of 29 Photos: Zika virus outbreak Aedes aegypti mosquitos are seen at the University of Sao Paulo on January 8. Researchers from the Pasteur Institute in Dakar, Senegal, came to Brazil to train local researchers to combat the Zika virus epidemic. Hide Caption 29 of 29

The mosquito-borne disease is a cause of microcephaly , according to the World Health Organization, but Schuchat said experts are now linking the virus to premature birth, eye problems and other neurological conditions in babies born to mothers who were infected while pregnant.

These concerns are no longer limited to exposure to the virus only during the first trimester. There is reason to be concerned throughout the pregnancy.

Schuchat also noted revised surveillance maps of the Zika-carrying mosquito, Aedes aegypti, released last month, showing that the insects could be more widespread than previously thought, reaching as far north as San Francisco and New York.

Fauci said researchers are on track with their goal to begin a clinical trial for a vaccine in September. He also said his teams have screened 62 existing drugs as possible treatments. Fifteen have been identified for further research, although he cautioned they may not pan out.

Progress in the lab

Progress is also being made in the lab with the recent molecular discovery that potentially sheds light on why the virus, which is so similar to dengue fever, infects neurological tissue.

Fauci said there are now two mouse models that could help researchers understand how and why neurological tissue is infected by the virus. And with a monkey model is allowing, they can compare how the virus behaves when the host is pregnant as compared with not pregnant.

Photos: First Zika transmitted via sex Photos: First Zika transmitted via sex Microbiologist Brian Foy poses on a hillside above the villages of Ibel and Ndebou in southeastern Senegal in the summer of 2008. Senegal is a small country in West Africa. Hide Caption 1 of 12 Photos: First Zika transmitted via sex From left: Graduate student Kevin Kobylinski, African researcher Massamba Sylla and CSU microbiologist Brian Foy pause during mosquito collection in Senegal. Hide Caption 2 of 12 Photos: First Zika transmitted via sex Brian Foy aspirates malaria-causing mosquitoes inside a villager's home in Ibel, Senegal. Only female Anopheles mosquitoes transmit malaria; they pick up a parasite called a plasmodium from infected people when they bite to obtain blood needed to nurture their eggs. Hide Caption 3 of 12 Photos: First Zika transmitted via sex Research assistant Alassane aspirates mosquitoes inside a villager's home. After feeding on humans during the night, the mosquitoes often hide in bedding and along ceiling rafters. Hide Caption 4 of 12 Photos: First Zika transmitted via sex A trap at the end of electronic aspirator shows collected mosquitoes. According to the World Health Organization, there were about 627,000 deaths from malaria in 2012; 90% were in sub-Saharan Africa. Hide Caption 5 of 12 Photos: First Zika transmitted via sex After collection in the trap of the electronic aspirator, the mosquitoes must be sucked out and transferred to specially prepared collection cups holding sugar water. Hide Caption 6 of 12 Photos: First Zika transmitted via sex African researcher Massamba Sylla, left, and graduate student Kevin Kobylinski visit a villager's home in Ibel, Senegal. Hide Caption 7 of 12 Photos: First Zika transmitted via sex The verdant village of Ndebou, in southeastern Senegal. The warm climate of Senegal makes it an ideal breeding environment for mosquitoes, particularly in the wet season. Hide Caption 8 of 12 Photos: First Zika transmitted via sex Villagers in Ndebou, Senegal, are part of a study on a parasite drug called ivermectin. The blood of villagers taking this medication seems to kill any mosquitoes that bite them. Hide Caption 9 of 12 Photos: First Zika transmitted via sex Kevin Kobylinski poses with village children. Hide Caption 10 of 12 Photos: First Zika transmitted via sex Kevin Kobylinski adds sugar water to collected mosquitoes. The research team compared the life span of mosquitoes from Ibel, where villagers where taking ivermectin, to mosquitoes collected from Ndebou, where villagers where not on the medication. Hide Caption 11 of 12 Photos: First Zika transmitted via sex From left: Kobylinski, Sylla and Foy dissect dead mosquitoes in their makeshift Senegal lab. Hide Caption 12 of 12

The end point is to protect Americans, especially pregnant women, which is why the agencies have been working around the clock. They can't say for sure how widespread the virus will be in the United States.

So far there have been at least 346 cases of the virus in the continental United States, according to the CDC. Most of these among travelers returning from currently affected countries and territories. There are no reported cases of mosquito transmitted Zika infection at this time.

"While we absolutely hope we don't see widespread local transmission in the continental U.S., we need the states to be ready for that," Schuchat said.

In the U.S. territories of Puerto Rico, American Samoa and the U.S. Virgin Islands, however, there have been 354 cases of the virus so far, most of them locally transmitted in their tropical climates. This is why the CDC is concerned. Schuchat said there could be hundreds of thousands of cases of Zika virus in Puerto Rico and that hundreds of babies could be affected by microcephaly.

As they've done before, they appealed to Congress for an emergency $1.9 billion to keep the virus at bay.

In February, the administration asked Congress for $1.9 billion in emergency supplemental funding to fight the Zika virus. Congress has yet to act on that request.

Last week, the White House said it was redirecting $589 million to the cause. The White House made it clear the $1.9 billion was still needed and the redirected money, which includes $510 million of unused Ebola funds, would need to be replaced.

Fauci echoed that Monday. He said the money also being taken from work being done on tuberculosis and malaria.

"If we don't refurbish that money, those programs are going to stop when they reach the point that they run out of money. What we're trying to do is keep everything going," he said.

Then he became more direct, "I can't image that we're not going to be given the money when we reach the point when every time we come in front of you we tell you things that are more serious."

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Without directly telling Congress to approve the funding request, White House press secretary Josh Earnest told reporters the information from Schuchat and Fauci would "serve as motivation for members of Congress to pay careful attention to this top priority."

"We can't assume that we're not going to have a big problem. We know with other viruses we've had bigger problems than we expected. We're taking this very seriously." Schuchat said.