West nile virus who is affected

WNV-specific IgG is typically detectable from eight days post onset of symptoms onwards and may persist for multiple years. Therefore, diagnosis based on IgG requires testing of an acute and convalescent serum to demonstrate seroconversion or a minimal four-fold increase in IgG titers. WNV diagnosis based on serology is severely hampered by extensive cross-reactivity between antibodies triggered by related viruses of the genus Flavivirus i.

In addition, an acute flavivirus infection may boost cross-reactive antibodies due to previous infection with or vaccination against another flavivirus, thereby obscuring antibody response to the present acute infection. Positive results obtained with these type of assays should be confirmed by virus neutralisation tests VNT; plaque reduction neutralisation test — PRNT80 and PRNT90 , preferably by parallel testing of acute and convalescent serum samples to distinguish recent infection from past infections.

To exclude cross-reactions with other flaviviruses, PRNTs should be performed simultaneously against all potential flaviviruses. Such tests require biosafety level 3 facilities and appropriate reference viruses. West Nile virus infection can be confirmed by virus genome detection or virus isolation.

Viral genome is typically detectable in plasma from 2—18 days post-infection and up to five days post-onset of symptoms, although prolonged viremia up to 35 days after symptom onset has been reported. There is evidence that whole blood is the best sample type, with Requirements for sensitivity of assays used depend on setting, e.

SoHO screening of population samples versus identification of clinical cases. Virus isolation is not considered as a test of choice for diagnosis, as it requires biosafety level 3 facilities and it takes up to five days to obtain a cytopathogenic effect.

WNV antigen detection by immunohistochemistry is possible in post-mortem tissue of fatal encephalitis cases. No specific prophylaxis or treatment exist for WNV infections. The only available treatment is supportive care [9]. In affected areas, blood establishments [1] should follow recommendations provided in the EU preparedness plan for blood safety [39]. Donors of organs, tissues and cells living in or returning from an affected area should be tested for WNV infection.

Systematic collection of epidemiological information on WNV infection among donors and recipients of SoHO is an important tool for national authorities to better assess the risk of transmission and impact of preventive measures on the availability of SoHO. According to the preparedness plan for WNV blood safety in the EU [39], blood establishments in affected areas should:. Mosquito vectors may be controlled through larval source reduction and measures against adult mosquitoes.

Vector breeding sites include stagnant and often dirty water collections in dishes, buckets, barrels and cans, flowerpots, rain gutters, discarded tires and other containers that can collect water. In urban environments, infrastructure such as underground heating, sewage pipes and basements liable to flooding can act as breeding and resting sites for vectors.

Specific methods for vector control to prevent transmission of WNV have been infrequently evaluated for their impact on reducing human cases [40]. Personal protective measures against mosquito bites include the use of mosquito bed nets preferably insecticide-treated nets , sleeping or resting in screened or air-conditioned rooms, the wearing of clothes that cover most of the body, and the use of mosquito repellent in accordance with the instructions indicated on the product label.

West Nile virus infection. Facts Surveillance and disease data Threats and outbreaks Prevention and control. Factsheet about West Nile virus infection. Twitter Facebook Linked In Mail. Epidemiological criteria At least one of the following epidemiological links: Animal to human transmission residing, having visited or having been exposed to mosquito bites in an area where WNV is endemic in horses or birds Human to human transmission vertical transmission, blood transfusion, transplants Case classification A.

Possible case Not applicable B. Probable case Any person meeting the clinical criteria and with at least: an epidemiological link; and a laboratory test for a probable case. Confirmed case Any person meeting laboratory criteria for case confirmation Note: Serological results should be interpreted according to previous exposure to other flavivirus infections and vaccination status.

The pathogen WNV is an enveloped positive-stranded ribonucleic acid RNA virus belonging to the Japanese encephalitis serocomplex Flavivirus genus, Flaviviridae family [6].

Animals WNV infections among equids are usually asymptomatic. Transmission WNV is transmitted in an enzootic cycle between mosquitoes and birds that respective acting as vectors and amplifying hosts.

Figure 1. West Nile virus transmission cycle. SoHo: substance of human origin. Diagnostics Laboratory methods for the diagnosis of a WNV infection are most commonly indirect detection based on serology, but can also entail direct detection of the virus. Direct detection West Nile virus infection can be confirmed by virus genome detection or virus isolation.

Case management and treatment No specific prophylaxis or treatment exist for WNV infections. According to the preparedness plan for WNV blood safety in the EU [39], blood establishments in affected areas should: temporarily interrupt blood collection or implement NAT screening for blood donations from WNV affected areas quarantine, retest and discard positive blood components in storage at the time of implementation of measures and retrieve and quarantine blood components derived from whole blood donated days prior the date of collection of the ID-NAT-positive donation enhance donor post-donation information, especially about fever, influenza-like illness or other acute symptoms within 15 days after donation strengthen post-transfusion haemovigilance and perform look-back analysis in any case of transfusion-transmitted WNV infection for a period dating days prior to the donation of implicated blood components; and consider the use of pathogen inactivation procedures.

Vector control Mosquito vectors may be controlled through larval source reduction and measures against adult mosquitoes. Infection control, personal protection and prevention Personal protective measures against mosquito bites include the use of mosquito bed nets preferably insecticide-treated nets , sleeping or resting in screened or air-conditioned rooms, the wearing of clothes that cover most of the body, and the use of mosquito repellent in accordance with the instructions indicated on the product label.

Read more on the ECDC website. Weekly updates: West Nile virus transmission season. Historical data by year - West Nile virus seasonal surveillance. Data West Nile virus risk assessment tool Tool - 1 Jul Publication The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in Surveillance report - 12 Dec Data Mosquito-borne diseases: An emerging threat Infographic - 12 Aug Read more on external websites.

Peer-Reviewed Publication Diagnosis of west nile virus human infections: Overview and proposal of diagnostic protocols considering the results of external quality assessment studies Sep Guide to the preparation, use and quality assurance of blood components — 19th Edition. References United Nations Statistics Division. New York: U N; [cited 20 September ]. European Centre for Disease Prevention and Control.

People with certain medical conditions, such as cancer, diabetes, hypertension, kidney disease, and people who have received organ transplants, are also at greater risk. Recovery from severe illness might take several weeks or months. Some effects to the central nervous system might be permanent. About 1 out of 10 people who develop severe illness affecting the central nervous system die.

Diagnosis See your healthcare provider if you develop the symptoms described above. Your healthcare provider can order tests to look for West Nile virus infection.

To learn more about testing, visit our Healthcare Providers page. Treatment No vaccine or specific medicines are available for West Nile virus infection. Over-the-counter pain relievers can be used to reduce fever and relieve some symptoms In severe cases, patients often need to be hospitalized to receive supportive treatment, such as intravenous fluids, pain medication, and nursing care.

If you think you or a family member might have West Nile virus disease, talk with your health care provider.

Repellents containing a higher concentration of active ingredient such as DEET provide longer-lasting protection. Read the directions to find out how long your product will last.

Most people infected with the West Nile virus will have only mild symptoms. However, if any of the following serious symptoms develop, seek medical attention right away:. Health Home Conditions and Diseases.

But, the virus can cause life-threatening illnesses, such as: Encephalitis inflammation of the brain Meningitis inflammation of the lining of the brain and spinal cord Meningoencephalitis inflammation of the brain and its surrounding membrane What causes West Nile virus? What are the symptoms of West Nile virus?

These are the most common symptoms of West Nile fever: Fever Headache Body aches Skin rash on trunk of body Swollen lymph glands The more severe form of the West Nile virus affects mostly older adults.

It occurs when the virus crosses the blood-brain barrier and can cause: Headache High fever Neck stiffness Stupor a state of impaired consciousness, extreme lethargy, and reduced reactivity to outside stimuli Disorientation Coma Tremors Convulsions Muscle weakness Paralysis The symptoms of West Nile virus may look like other conditions or health problems. What are the risk factors for West Nile virus?

How is West Nile virus diagnosed? Your doctor will order a blood test to check for antibodies to the West Nile virus. He or she may also do a lumbar puncture to test cerebrospinal fluid for signs of infection. How is West Nile virus treated? Your healthcare provider will figure out the best treatment based on: How old you are Your overall health and medical history How sick you are How well you can handle specific medications, procedures, or therapies How long the condition is expected to last Your opinion or preference There's no specific treatment for West Nile virus-related diseases.

If a person gets the more severe form of the disease, West Nile encephalitis or meningitis, treatment may include intensive supportive therapy, such as: Hospitalization Intravenous IV fluids Breathing support ventilator Prevention of other infections such as pneumonia or urinary tract infections Nursing care What are the complications of West Nile virus?

However, the virus can cause life-threatening illnesses, such as Encephalitis inflammation of the brain Meningitis inflammation of the lining of the brain and spinal cord Meningoencephalitis inflammation of the brain and its surrounding membrane Can West Nile virus be prevented?

If you spray your clothing, there's no need to spray repellent containing DEET on the skin under your clothing. When possible, wear long-sleeved shirts and long pants treated with repellents containing permethrin or DEET since mosquitoes may bite through thin clothing. Don't directly apply repellents containing permethrin to exposed skin. Consider staying indoors at dawn, dusk, and in the early evening. These are peak hours for mosquito bites, especially those mosquitoes that carry the West Nile virus.

Limit the number of places for mosquitoes to lay their eggs by getting rid of standing water sources from around your home. To boost your protection from insect repellent, remember: Sweating, or water may call for reapplication of the product.

If you aren't being bitten, you don't need to reapply repellent. Use enough repellent to cover exposed skin or clothing. Don't apply repellent to skin that's under clothing. Heavy application isn't needed for protection. Don't apply repellent to cuts, wounds, or irritated skin. After returning indoors, wash treated skin with soap and water.

Don't spray aerosol or pump products in enclosed areas. Don't apply aerosol or pump products directly to your face.