Zika fever is a viral infection that is usually mild and short-lived. Many people with Zika fever have no symptoms, but early symptoms of Zika fever can include fever, rash, joint pain, red eyes, headache, and muscle aches. It may help to know that doctors have studied this condition for decades, and most people recover within a few days to about 1 week. Zika fever can affect adults and children, and it is usually not fatal, but infection during pregnancy can cause serious birth defects in a developing baby. Treatment for Zika fever is supportive and includes rest, fluids, and medicine such as acetaminophen or paracetamol for fever and pain.
How many people live with Zika fever?
There is no single, widely accepted estimate of how many people are living with Zika fever worldwide or in the United States at any given time, because Zika is usually a short-term infection and health agencies track outbreaks and reported cases rather than an ongoing total (WHO, 2024; CDC, 2024). In other words, recent sources report cases by outbreak or by year, but not a reliable global or U.S. "people living with Zika fever" number (WHO, 2024; CDC, 2024).
Overview
Zika feverSymptoms
Zika fever often causes a mild fever, rash, joint pain, red eyes, headache, and muscle aches. Many people with Zika fever have no symptoms, and when illness happens, it is usually mild and lasts several days to a week.
Outlook and prognosis
For most people, Zika fever is mild and improves within several days to a week. The outlook is usually very good, though pregnant people need prompt medical care because Zika fever can seriously affect a developing baby.
Causes and risk factors
Zika fever is usually caused by a bite from an infected Aedes mosquito. Risk rises with travel to or living in outbreak areas, unprotected sex with an infected partner, and pregnancy exposure. Rarely, it spreads through blood transfusion.
Genetic influences
Genetics do not play a major role in whether someone gets Zika fever. The main risk comes from exposure to the virus, though individual genetic differences may slightly affect immune response and illness severity.
Diagnosis
Zika fever is diagnosed based on symptoms, recent travel or mosquito exposure, and lab tests on blood or urine. Early symptoms of Zika fever can overlap with other infections, so testing helps confirm the diagnosis.
Treatment and drugs
Treatment for Zika fever focuses on rest, fluids, and acetaminophen for fever or aches. Avoid aspirin and ibuprofen until dengue is ruled out, because they can raise bleeding risk. Most people recover at home with supportive care.
Symptoms
Many people with Zika fever feel only mildly unwell, and some have no symptoms at all. When symptoms do happen, they usually begin within 3 to 14 days after exposure and often last several days to about a week. The early symptoms of Zika fever can look like a simple viral illness, so they are easy to miss. Symptoms vary from person to person and can change over time.
Zika fever often causes a low fever rather than a very high temperature. You may feel warm, chilled, or generally run-down for a few days.
A flat or slightly raised rash often starts on the face or body and can spread to the arms and legs. It may itch, and for many people with Zika fever this is one of the most noticeable signs.
The eyes can look pink or bloodshot because the surface becomes irritated. This usually is not the thick, sticky kind of eye infection, but it can still feel bothersome.
Achy or stiff joints are common, especially in the hands, wrists, knees, ankles, or feet. Small tasks like opening a jar or walking downstairs may feel more uncomfortable than usual.
How people usually first notice Zika fever?
People usually first notice Zika fever through a mild illness that starts suddenly, often with a blotchy rash, low-grade fever, red eyes, joint pain, muscle aches, or headache after a mosquito bite or travel to an area where Zika is spreading. Many people with Zika fever feel only slightly unwell, and some have no symptoms at all, which can make the infection easy to miss. When symptoms do appear, they usually begin within about 3 to 14 days after exposure and are often mild, but medical advice is especially important during pregnancy because infection can affect a developing baby.
Types of Zika fever
Zika fever can look quite different from one person to the next, and many people have no symptoms at all. Symptoms don’t always look the same for everyone. When symptoms do happen, the early symptoms of Zika fever are usually mild, but a small number of people develop more serious nerve problems, and infection during pregnancy can affect the baby in distinct ways.
No symptoms
Many people with Zika fever feel completely well and may only learn they were infected after testing or during an outbreak. Even without symptoms, the virus can still be present in the body for a time.
Typical illness
This is the most common symptomatic form of Zika fever and usually causes a mild fever, rash, red eyes, joint pain, headache, or muscle aches. Some may find these symptoms last several days to about 1 week and then improve on their own.
Neurologic complications
A small number of people develop nerve-related problems after Zika fever, most notably Guillain-Barré syndrome, which can cause weakness, tingling, and trouble walking. These symptoms are uncommon but much more serious than the usual mild illness and need urgent medical care.
Pregnancy-related infection
When Zika fever happens during pregnancy, the pregnant person may have mild symptoms or none at all, but the infection can still affect the developing baby. The main differences show up in the fetus or newborn, including a higher risk of congenital Zika syndrome with brain and developmental problems.
Can I slow down the onset of symptoms?
No, there is no good evidence that lifestyle changes or medicines can meaningfully delay the start of symptoms in Zika fever once the infection has happened. The main proven step is to lower the chance of getting Zika in the first place by avoiding mosquito bites and using condoms or avoiding sex with a partner who may have been exposed; this reduces the risk of infection, but it does not prevent illness after infection has already begun. There is no widely used preventive medicine for Zika, but if you may have been exposed, especially during pregnancy, early medical advice can help with testing and follow-up, and most people recover fully with supportive care.
What genetics can tell you about symptoms
Genetics can tell us a little about why Zika fever affects people differently, but it cannot reliably predict exactly which symptoms someone will have. Most people with Zika have mild illness, and differences in symptoms are thought to depend more on factors like pregnancy, immune response, prior exposure to related viruses, and the timing of infection than on any single gene change. Researchers are still studying whether inherited genetic differences affect symptom severity or complications, so at this point genetics has only a limited role in predicting symptoms of Zika fever.
Causes and risk factors
For many, the risk of Zika fever starts with a bite from an infected Aedes mosquito in a place where the virus is spreading. Warm areas with standing water raise risk, and so does time outdoors without repellent or window screens. Zika fever can also spread through sex and, rarely, through blood transfusion, so recent travel and unprotected sex are important risk factors for Zika fever. Knowing the risks can help you feel more in control. Genes are not known to play a major role in who gets Zika fever, but pregnancy is a key biological factor because the virus can harm a developing baby.
What are the most common causes or risk factors?
Zika fever is caused by infection with the Zika virus, most often after a bite from an infected mosquito, especially in places where Zika is spreading. The biggest risk factors are living in or traveling to those areas, getting mosquito bites during the day, and not using steps like repellent, long sleeves, or window screens to lower exposure. Zika can also spread through sex with an infected partner and, less often, through blood exposure, and this is especially important in pregnancy because the virus can pass to the developing baby.
Environmental and biological risk factors
Zika fever becomes more likely when you are exposed to infected mosquitoes or, less often, infected body fluids. The main risk factors for Zika fever during travel or daily life are where the virus is circulating, the local mosquito conditions, and whether your body has seen the virus before. Doctors often group risks into internal (biological) and external (environmental).
Living in or traveling to places where Zika is actively spreading raises the chance of infection. Risk is highest in tropical and subtropical regions where the mosquitoes that carry the virus are established.
Warm temperatures, humidity, and rainy periods help mosquito numbers rise. When standing water collects in buckets, gutters, or plant trays, Zika fever can spread more easily in the community.
The mosquitoes that spread Zika often live close to people and usually bite during the daytime. Homes or buildings without good window screens, air conditioning, or mosquito control can increase exposure.
People who have never had the virus before do not have existing immune protection against Zika. This can make travelers, visitors, and newly arrived residents more likely to get Zika fever when local transmission is happening.
Genetic risk factors
Zika fever is caused by infection with the Zika virus, not by an inherited gene change. For people wondering whether Zika fever runs in families, the answer is generally no. At this time, there are no well-established genetic causes of Zika fever and no routine genetic test used to predict who will get it.
No inherited cause: Zika fever is not considered a genetic disease. You do not inherit Zika fever from your parents through your DNA.
Family history: Having relatives who had Zika fever does not, by itself, point to a proven inherited risk. Family history is not used as a genetic warning sign for Zika fever in routine care.
Immune gene research: Researchers are studying whether small inherited differences in immune-system genes may affect how the body responds to Zika infection. At this point, these findings do not give doctors clear, usable genetic risk factors for Zika fever.
Pregnancy and genes: Zika-related birth problems are linked to infection during pregnancy, not to a known inherited gene in the baby or parent. Standard genetic testing does not explain most of these cases.
Lifestyle risk factors
For Zika fever, the main lifestyle-related risks come from everyday habits that increase exposure to infected mosquitoes or sexual transmission. Unlike many chronic illnesses, diet and exercise are not known to meaningfully change the chance of getting Zika fever. In practice, how lifestyle affects Zika fever is mostly about travel choices, bite prevention habits, and safer sex behaviors.
Traveling to areas with active Zika transmission can raise the chance of infection, especially when trips involve prolonged outdoor exposure. Delaying nonessential travel during outbreaks or taking strict precautions can lower risk.
Skipping insect repellent, wearing more skin-exposing clothing, or not using screens and bed nets can increase mosquito bites and the risk of Zika fever. Consistent bite prevention is one of the most important lifestyle risk factors for Zika fever.
Spending long periods outdoors during peak mosquito activity without protection can increase exposure to infected mosquitoes. Planning activities to reduce bites and using protective clothing can help lower risk.
Zika can spread through sex, so unprotected vaginal, anal, or oral sex with an infected or recently exposed partner can increase risk. Condom use and temporary abstinence after possible exposure can reduce transmission.
Risk prevention
For many, preventing Zika fever comes down to avoiding mosquito bites and taking extra care with travel and sex if exposure is possible. Zika fever is usually spread by infected Aedes mosquitoes, but it can also pass through sex and from a pregnant person to a fetus. Prevention is about lowering risk, not eliminating it completely. This matters most in pregnancy, since infection can sometimes harm a developing baby even when symptoms are mild or absent.
The best way to lower the risk of Zika fever is to prevent mosquito bites, especially during the day when Aedes mosquitoes are most active. Use an EPA-registered insect repellent, wear long sleeves and long pants, and choose screened or air-conditioned spaces when possible.
Mosquitoes that spread Zika fever breed in small amounts of still water around homes and buildings. Empty or scrub items like buckets, plant saucers, birdbaths, and gutters regularly so mosquitoes have fewer places to lay eggs.
If Zika fever is spreading in a destination, postponing nonessential travel can reduce risk, especially during pregnancy. If travel cannot be avoided, strict bite prevention before, during, and after the trip becomes even more important.
Zika can spread through vaginal, anal, and oral sex, even if a partner feels well. Using condoms correctly every time or avoiding sex for the recommended period after possible exposure helps reduce transmission.
Can you prevent Zika fever?
You cannot prevent Zika fever with complete certainty, but you can lower the risk. The best-known ways are to avoid mosquito bites, especially in places where Zika is spreading, and to reduce sexual spread by using condoms or avoiding sex if you or your partner may have been exposed. This matters most during pregnancy, because preventing infection can help protect the baby.
Transmission
Zika fever is usually passed to people through the bite of an infected Aedes mosquito, the same type that can spread dengue and chikungunya. It can also spread through sex, from a pregnant person to the baby during pregnancy, and rarely through blood transfusion, so when people ask how Zika fever spreads, the answer is not just mosquito bites.
Zika fever is not considered highly contagious in everyday contact, and it does not spread through coughing, sneezing, hugging, or sharing food. For many living with Zika fever, the main risk is being bitten in an area where the virus is circulating, while sexual spread is less common but still important, especially during pregnancy.
When to test your genes
For Zika fever, genetic testing of your own genes is not a routine tool for early detection or personalized care. What matters is testing for the virus itself after possible mosquito exposure, travel to an affected area, symptoms, or pregnancy. If you are pregnant or planning pregnancy, ask promptly about Zika testing guidance.
Diagnosis
Zika fever is usually diagnosed by looking at recent symptoms together with where you have traveled, where you live, and whether you may have been exposed to mosquitoes or sex-related spread. The illness can look like other viral infections, so doctors often need tests to confirm it, especially early on. It’s natural to worry when symptoms don’t have a clear explanation. The diagnosis of Zika fever also matters in pregnancy, because even a mild infection can affect care decisions.
Doctors ask about fever, rash, red eyes, joint pain, headache, and when these symptoms started. They also look at how mild or short-lived the illness has been, since many people with Zika fever feel only slightly unwell.
Recent travel to an area with Zika, mosquito bites, and sexual contact with someone who may have been exposed can all raise suspicion. A detailed family and health history can help, but recent exposure is usually the key part for Zika fever.
Blood tests can look for the virus itself in the first days after symptoms begin. This is often the most useful way to confirm how Zika fever is diagnosed early in the illness.
Urine tests may also detect the virus, sometimes for a bit longer than blood tests. Doctors often order blood and urine tests together to improve the chance of finding an infection.
How is Zika fever diagnosed?
Doctors usually diagnose Zika fever by looking at symptoms such as fever, rash, red eyes, and joint pain, and by asking about recent travel or sexual contact that could have led to exposure. To confirm it, they may test blood or urine, especially in the first 1 to 2 weeks after symptoms begin, to look for the virus itself or signs that the body has reacted to it. Because Zika can look a lot like other mosquito-borne illnesses, lab testing is often needed to tell the difference.
Stages of Zika fever
Zika fever does not have defined progression stages. This is because it is usually a short-term viral illness rather than a condition that steadily worsens step by step over time. Doctors usually start with a conversation about symptoms such as fever, rash, red eyes, joint pain, and recent travel or mosquito exposure, since the early symptoms of Zika fever can look like other infections. Diagnosis may be confirmed with blood or urine tests, especially in the first days after symptoms begin, and follow-up is guided by symptoms, pregnancy status, and any concerns about complications.
Outlook and prognosis
The outlook for most people with Zika fever is very good, with symptoms usually being mild and resolving on their own within about 2 to 7 days. Most infected people recover fully without lasting health problems, and hospitalization is uncommon. Death from Zika fever is very rare, but severe neurologic complications such as Guillain-Barré syndrome can occur in a small number of cases and may prolong recovery. The most serious prognosis concerns infection during pregnancy, because congenital Zika syndrome can cause miscarriage, stillbirth, or lifelong disabilities in the baby, including microcephaly and other brain and eye abnormalities. For adults and children who are not pregnant, long-term outcomes are generally favorable with supportive care and monitoring for complications.
Long-term effects
Most people with Zika fever recover fully within days to weeks, and lasting problems are uncommon. Still, the long-term effects of Zika fever can matter most when the infection affects the nervous system or happens during pregnancy. Doctors often describe these as long-term effects or chronic outcomes, although not everyone will have them.
Some people continue to feel tired, achy, or generally run-down for weeks after the rash and fever are gone. For many, this can mean getting through work, exercise, or daily chores feels harder than usual for a while.
Zika fever has been linked to Guillain-Barré syndrome, a rare nerve problem that can cause weakness, tingling, and sometimes trouble walking. Recovery often happens over months, but some people are left with ongoing weakness, numbness, or fatigue.
In rare cases, Zika can affect the brain or spinal cord and lead to lasting neurologic problems. These may include weakness, movement trouble, or changes in thinking, depending on which part of the nervous system was affected.
If Zika fever happens during pregnancy, the infection can pass to the developing baby and cause serious birth differences. The risk is not the same in every pregnancy, but the effects can be lifelong.
How is it to live with Zika fever?
For most people, living with Zika fever means a short-lived illness that feels a lot like a mild viral infection, with tiredness, rash, fever, joint pain, red eyes, and the need to slow down for several days to a week. Daily life is usually affected more by fatigue and body aches than by severe disability, but the situation can feel much heavier if you are pregnant or trying to conceive, because Zika infection during pregnancy can harm a developing baby. It also affects the people around you, since the virus can spread through mosquitoes and through sex, so preventing bites, using condoms, and taking extra care around pregnant partners or family members becomes an important part of protecting others.
Treatment and drugs
Treatment for Zika fever is mainly supportive, because there is no specific antiviral drug that cures the infection. Most people improve with rest, plenty of fluids, and medicines to lower fever and ease aches, such as acetaminophen; doctors usually advise avoiding aspirin and other nonsteroidal anti-inflammatory drugs until dengue has been ruled out, since dengue can also cause fever and rash and may raise the risk of bleeding. Supportive care can make a real difference in how you feel day to day, especially if the early symptoms of Zika fever leave you tired, sore, and wiped out for several days. If Zika fever occurs during pregnancy, care is more closely monitored because the virus can affect the developing baby, and follow-up may include extra prenatal scans and specialist input. Severe illness is uncommon, but anyone with dehydration, worsening weakness, trouble breathing, or nerve symptoms needs prompt medical care.
Can you cure Zika fever?
No, there is no specific cure for Zika fever at this time. Most people get better on their own with rest, plenty of fluids, and medicine to ease fever, headache, and body aches, while doctors watch for any problems; if you are pregnant or may be pregnant, it is important to contact a doctor promptly because Zika can affect the baby.
Non-drug treatment
Zika fever is usually managed with supportive care at home, aimed at easing symptoms while the body clears the infection. For many, treatment begins not at the pharmacy, but with rest, steady fluids, and simple comfort measures that make the day easier. If early symptoms of Zika fever start after travel or mosquito exposure, getting medical advice can help confirm the cause and spot warning signs. Most people recover within days to about a week, but some need closer follow-up, especially during pregnancy or if nerve symptoms appear.
Extra sleep and lighter daily activity can help your body recover while fever, rash, or aches settle down. Many living with Zika fever find it helps to pause exercise, work, or travel until energy starts to return.
Drinking water, soups, or oral rehydration drinks can help prevent dehydration, especially if fever has you sweating or eating less. Small, frequent sips may be easier if you feel washed out or mildly nauseated.
A cool room, light clothing, and a lukewarm compress can ease fever and body discomfort without medicine. If itchy skin is bothering you, gentle skin care and avoiding hot showers may help.
Red or irritated eyes often feel better with rest, sunglasses outdoors, and avoiding contact lenses until symptoms improve. Clean hands and not rubbing your eyes can also reduce extra irritation.
Your genes may have an impact on how drugs work for you
For most people with Zika fever, genes do not play a big role in treatment because care is usually simple and focused on easing symptoms, like rest, drinking fluids, and using common fever or pain medicine such as acetaminophen. People’s bodies can naturally break down medicines at slightly different speeds, so one person may get good relief while another feels it wears off sooner or is more likely to have side effects, but this is not something doctors usually test for in Zika fever. In everyday care, genetic testing is not a routine part of treating Zika, because there is no standard virus-fighting medicine whose use is guided by these differences.
Pharmacological treatments
Most people with Zika fever do not need a specific antiviral drug, and treatment focuses on easing symptoms while the body clears the infection. Drugs that target symptoms directly are called symptomatic treatments. In practice, this means rest, fluids, and a few common medicines for fever, aches, rash, or itching, which is the usual approach to how Zika fever is treated.
Acetaminophen, also called paracetamol, is usually the first choice for fever, headache, and body aches in Zika fever. It can help people feel more comfortable while they recover at home.
Ibuprofen or naproxen may be used for pain or fever only after dengue has been ruled out. This matters because dengue can increase bleeding risk, and these medicines can make that worse.
Aspirin is generally avoided when Zika fever is first suspected until dengue is excluded. It is also usually not given to children or teenagers with viral illnesses because of rare but serious side effects.
Antihistamines such as cetirizine, loratadine, or diphenhydramine may help if the rash is very itchy. Some can make you sleepy, so timing and choice may matter.
Genetic influences
For most people, catching Zika fever has much more to do with mosquito exposure, travel, or sexual contact than with what runs in the family. Genetics is only one piece of the puzzle, but researchers are studying whether small differences in immune-system genes help explain why some people have more severe Zika fever symptoms while others notice little or none. At this point, there is no known inherited gene change that directly causes Zika fever, because the illness itself comes from infection with the Zika virus. Scientists are also looking at the virus's own genes, since changes in the virus may affect how easily it spreads or how likely it is to cause complications, especially during pregnancy. For families worried about pregnancy and birth effects, genetics may play a small supporting role, but exposure to the virus remains the main factor.
Is Zika fever genetic?
Genetics do not play a major role in whether someone gets Zika fever. The main risk comes from exposure to the virus, though individual genetic differences may slightly affect immune response and illness severity.
Having a genetic risk is not necessarily a diagnosis
Changes in genes are a normal part of being human and are common across the population. Most of these changes do not directly affect health and are simply part of normal human variation. For many genes, having a change connected with a condition suggests a possible link rather than a definite diagnosis, especially when several genes and environmental influences play a role. In some situations, though, one well-studied change in a particular gene is enough to confirm the diagnosis.
Pharmacogenetics—how genetics influence drug effects
For most people with Zika fever, treatment is mainly about easing everyday symptoms such as fever, rash, headache, and joint pain with rest, fluids, and acetaminophen. Doctors usually avoid aspirin, ibuprofen, and similar pain relievers at first until dengue has been ruled out, because dengue can also cause fever and rash and may raise the risk of bleeding. Genetics is only one factor, and in Zika fever it does not usually change which medicines your doctor recommends. Researchers are studying whether inherited differences in the immune system affect how strongly some people respond to the virus, but this has not led to routine genetic testing or gene-based drug choices for Zika fever. So when people ask about the best treatment for Zika fever, care is still guided mostly by symptoms, pregnancy status, travel history, and watching for complications rather than by DNA results.
Interactions with other conditions
Zika fever can overlap with other mosquito-borne illnesses, especially dengue and chikungunya, because the early symptoms of Zika fever can look very similar: fever, rash, joint pain, red eyes, and feeling generally unwell. In places where these infections circulate together, someone might notice their symptoms flare when another condition is active, or doctors may need blood tests to sort out which virus is causing the illness. This matters because dengue can sometimes become more serious, with bleeding or severe dehydration, while Zika fever is usually milder in the person infected but can pose major risks during pregnancy. Zika fever has also been linked with Guillain-Barré syndrome, a rare nerve condition that can cause weakness or paralysis, so new trouble walking, lifting, or breathing needs urgent medical care. People living with immune system problems or other serious illnesses may need closer follow-up, even though most Zika fever infections improve with rest, fluids, and time. Talk with your doctor about how your conditions may influence each other, especially if you are pregnant, recently traveled, or live in an area where several mosquito-borne infections are common.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
What other conditions can cause similar symptoms to Zika fever?
The main conditions that can look like Zika fever are dengue and chikungunya, because all three can cause fever, rash, body aches, and joint pain, often after mosquito exposure. Other viral illnesses such as the flu or COVID-19 can sometimes seem similar at first, and if you have recently traveled, doctors may also think about malaria because fever can be an early sign.
History
In recent decades, awareness has grown around Zika fever, especially because it can turn what seems like a mild, short-lived illness into a much bigger concern during pregnancy. Many people with Zika fever have few symptoms or none at all, so for years it drew far less public attention than infections that made people much sicker right away.
Zika virus was first identified in 1947 in Uganda during research on mosquito-borne disease, and human infections were recognized soon after. For decades, Zika fever was reported only occasionally in parts of Africa and Asia, and it was generally thought of as an uncommon infection causing mild fever, rash, joint pain, and red eyes. In everyday life, that often meant someone might feel as if they had a brief flu-like illness, recover at home, and never know the exact cause.
That picture changed in the 2000s, when larger outbreaks were reported on Pacific islands and then in the Americas. As medical science evolved, doctors and public health teams began linking Zika fever not only to mosquito bites but also to serious pregnancy-related risks and, more rarely, nerve complications in adults. This was a major turning point, because the infection had long been seen as mild.
The 2015 to 2016 outbreak in Brazil brought global attention to Zika fever after researchers found a clear link between infection during pregnancy and birth defects affecting brain development, including microcephaly. Health agencies around the world responded quickly with travel guidance, mosquito control efforts, and advice for pregnancy planning. For many families, this changed Zika from a little-known tropical illness into something with real day-to-day decisions around travel, sex, and prenatal care.
Since then, research has helped explain how the virus spreads and why the effects can vary so much from one person to another. Testing has improved, although diagnosis can still be tricky because the early symptoms of Zika fever overlap with other mosquito-borne illnesses such as dengue and chikungunya. Today, the history of Zika fever is a reminder that infections once considered minor can become much more important when new outbreaks reveal risks that were not fully recognized before.