Can you develop immunity to west nile virus

A mosquito gets infected by biting a bird that is infected with the virus. An uninfected mosquito cannot bite an infected human and become infected. Mosquitoes also do not transmit the virus between people. Less often, the virus has been spread by blood transfusion, organ transplant, breastfeeding, and from mother to child during pregnancy. Donated blood is check for WNV before being used. West Nile virus is NOT spread by casual contact such as touching, kissing, or caring for someone who is infected.

West Nile virus is spread to humans commonly by the bite of infected mosquitoes. In rare instances, the virus has been spread by blood transfusion, organ transplant, breastfeeding, and from mother to child during pregnancy. Asymptomatic West Nile most people Most people - 80 percent- of the people who are infected with West Nile have no symptoms or may experience mild illness, then recover fully. Often, these people only know they have West Nile because the virus is detected when they have blood work done for an unrelated reason, such as blood donation or routine lab work.

West Nile Fever some people Up to 20 percent of people who are infected with West Nile contract West Nile Fever, a flu-like illness that causes symptoms such as fever, headache, body aches, nausea, and, less frequently, skin rash on chest, stomach and back, or sometimes swollen lymph glands or eye pain.

West Nile Neuroinvasive Disease few people Fewer than 1 percent of individuals infected with West Nile can develop West Nile neuroinvasive disease, a serious form of the virus that affects the nervous system. Symptoms include severe headache, high fever, stiff neck, disorientation, muscle weakness, numbness, tremors, vision loss, coma, or paralysis. These symptoms last several weeks, and can cause death or permanent brain damage.

The elderly are most at risk for this form of West Nile, but anyone who contracts West Nile has a chance of developing this most severe form. If you can get bitten by a mosquito, you are at risk for West Nile virus. People older than 50 are more likely to become ill and develop serious symptoms when infected because as we age, our bodies have a harder time fighting off disease. Being outside increases your risk of being bitten by a mosquito, which increases your risk for getting West Nile virus.

The best ways to avoid West Nile are to take precautions against mosquito bites, and to stay generally healthy so that your body is better able to fight off infection so that if you do get West Nile, you'll be less likely to get the more severe form of the virus.

The risk of West Nile transmission from medical procedures is very low — donated blood is tested before being used. Signs for West Nile virus infection begin to appear 2 to 15 days after infection being bitten by an infected mosquito that transmits the virus. Most people who are infected with West Nile virus have no symptoms or experience only mild illness. West Nile virus infection can only be diagnosed by a doctor.

If you think you have any of the signs or symptoms, you should make an appointment to see your doctor. If your doctor suspects that you may have West Nile virus infection, he or she will take your blood sample or draw spinal cord fluid. The eggs become larvae that remain in the water until they mature and fly off.

Weeds, tall grass and shrubbery provide an outdoor home for adult mosquitoes. They can also enter houses through unscreened windows or doors, or broken screens. Most mosquitoes will breed in discarded tires.

When are mosquitoes most active? Some mosquitoes are most active between dusk and dawn, when the air is calm. However, others may be present at any time of day, and feed during the daytime and at dusk. What bird s can carry West Nile virus? Although most birds can be infected with West Nile virus, crows, blue jays, magpies, hawks, owls and eagles are most likely to die from the virus.

Can you get West Nile virus directly from birds? There is no evidence that a person can get the virus from handling live or dead infected birds.

However, avoid bare-handed contact when handling any dead animals and birds. Use gloves or double plastic bags to place the carcass in a garbage can. Can other animals become infected? WNV can make horses very ill. It can also be detected in dogs, cats, bats, chipmunks, raccoons, skunks, squirrels, and domestic rabbits. It is important to remember that animals cannot transmit WNV to people.

How can I protect my family and myself? To reduce the mosquito population around your home and property, reduce or eliminate all standing water:. Remove all discarded tires on your property. Used tires have become an important source of mosquito breeding in the nation. Drill holes in the bottoms of recycling containers that are kept outdoors. Make sure roof gutters drain properly, and clean clogged gutters in the spring and fall.

Turn over plastic wading pools and wheelbarrows when not in use. Clean and chlorinate swimming pools, outdoor saunas and hot tubs. Use landscaping to eliminate standing water that collects on your property. The study determined that the vaccine is safe for California condors, stimulates protective antibodies, and protects against naturally circulating WNV Chang et al. Like humans, horses have a robust immune response to WNV that utilizes both the innate and adaptive responses.

In the early immune response, horses utilize an interferon-mediated IFN response. In one study that used WNV Kunjin subtype authors found increased levels of type I and type II interferon in blood leukocytes, lymph nodes, and spleen. In a project that investigated global gene expression of the central nervous system CNS of horses by sequencing the transcriptome of the brain and spinal cord, researchers identified gene ontology groups utilized in the WNV immune response.

These pathways also exist in humans, indicating similarities between the human and horse immune responses to WNV.

Furthermore, like birds, horses also mount an immune response to WNV using antibodies Bielefeldt-Ohmann et al. Pony foals have been shown to receive maternally-inherited antibodies as a means of passive immunity Wilkins et al. This strategy utilizes antibodies to rapidly activate the immune response to protect foals from infection.

Because of the negative impact of WNV on the human population throughout the U. The downstream ISGs include the IFIT interferon-induced protein with tetratricopeptide repeats genes and viperin, which inhibit viral infection and replication Jiang et al. This strategy of antagonizing the IFN response is common to flaviviruses. Apoptosis is another innate immune response in mammals that restricts WNV replication, and the mechanisms of apoptosis induction have been studied in murine models.

However, while apoptosis can be an effective method for eliminating virus from a host, it has a damaging effect on neurons. Although caspase 3 is activated during WNV infection, possibly in an attempt at an immune response, caspase 3 knockout mice have higher survival during WNV infection and less neuronal death than their wild-type counterparts Samuel et al.

These findings suggest that the net beneficial or detrimental outcome of apoptosis as an immune response could be dependent on the type of tissue and the specific pro-apoptotic pathway activated.

Indeed, a single nucleotide polymorphism in the OAS1b gene, namely rs, that contains a C to T substitution in the second intron of the gene, is a risk factor for human West Nile encephalitis and paralysis from WNV infection Bigham et al.

OAS1 has been demonstrated to undergo positive selection in Old World primates Fish and Boissinot, , indicating a historic interaction between flaviviruses like WNV and host immunity Daugherty and Malik, This pathway is conserved in birds and horses, as discussed in earlier sections. Passive immunity is also useful for rapid host protection to WNV.

Strikingly, the BAFFR-deficient mice can develop sustained protective immunity after treatment with immune sera Giordano et al. Together, this indicates that passive immunity could be utilized as a therapeutic option for human infection to induce a robust immune response. To the best of our knowledge, no studies have determined if antibodies to WNV are maternally-inherited in humans. While mammals do possess an RNAi pathway like insects, the IFN immune response takes precedence as the primary innate immune response Benitez et al.

Both insects and mammals utilize apoptosis as a rapid response to virus infection. Birds, horses, and humans all utilize an OAS response and passive immunity, which are both activated rapidly during infection and are effective at restricting WNV.

Presently, no approved vaccine or therapeutic exists for human use to prevent or treat WNV infection. There are, however, four approved horse vaccines in use in the U. Veterinary options include two inactivated whole virus vaccines, a non-replicating live recombinant canary pox vector vaccine, and an inactivated flavivirus chimera vaccine Ishikawa et al.

A number of human vaccines have been proposed, with some in clinical trials. One promising vaccine is ChimeriVax-WN02, which is a live, attenuated vaccine created by inserting the genes for the pre-membrane prM and envelope E proteins from WNV into the yellow fever 17D clone Arroyo et al. The vaccine completed a successful phase I clinical trial and two phase II clinical trials Monath et al.

Both versions of this vaccine completed successful phase I clinical trials. One notable impediment is the low and sporadic incidence of WNV activity, which would make it difficult to establish vaccine efficacy. Because of the logistical challenges of developing and licensing a vaccine for WNV, perhaps a more feasible avenue for prevention is the introduction of Wolbachia into the mosquito population. As discussed in an earlier section, Wolbachia reduces flavivirus titer in mosquitoes, and models predict that WNV eradication is possible with the introduction of Wolbachia Farkas et al.

Certainly, great caution should be taken to determine if the introduction of Wolbachia into the Culex population would have any detrimental effects on the greater ecosystem. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Adler Research Fund, and the Mary V. Schindler Equine Research Endowment. National Center for Biotechnology Information , U. Front Cell Infect Microbiol. Published online Apr 3. Laura R. Ahlers 1 and Alan G. Alan G. Author information Article notes Copyright and License information Disclaimer.

Edited by: Colleen B. Reviewed by: Jeremy V. Goodman ude. Received Jan 23; Accepted Mar The use, distribution or reproduction in other forums is permitted, provided the original author s and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.

No use, distribution or reproduction is permitted which does not comply with these terms. This article has been cited by other articles in PMC. Abstract Vector-borne diseases, including arboviruses, pose a serious threat to public health worldwide. Keywords: innate immunity, West Nile virus, Culex , host response, vector-borne disease. Open in a separate window. Figure 1. Culex mosquitoes as vectors of infection Mosquitoes in the culicine family carry WNV, and each species has a preferred geographical tropism, blood meal host, and daily and seasonal feeding pattern.

Table 1 Summary of the host responses of the animal hosts of West Nile virus. Author contributions LA wrote the manuscript in consultation with AG. Conflict of interest statement The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments We thank A. Carver for providing editorial comments for our manuscript. West Nile virus usually only causes mild symptoms, if any. Most people recover in a few days. Some symptoms may last a few weeks, such as weakness or fatigue.

But they will go away on their own. Most people who develop severe illness from West Nile virus recover. But your recovery could take weeks or months. You could have long-term illness, brain damage, or permanent disability. This article was contributed by: familydoctor. This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject. You may hear conflicting reports from different sources.

The U. Visit The Symptom Checker. Read More. Food Poisoning. Acute Bronchitis. Eustachian Tube Dysfunction. Bursitis of the Hip. Abnormal Uterine Bleeding. High Blood Pressure. Table of Contents. What is West Nile virus? However, about 1 in 5 people may have mild, flu-like symptoms, which include: Skin rash. Loss of appetite. Swollen lymph nodes lymph glands. An achy feeling in the back and muscles.