BioPerfectus - Unmasking the Menace of West Nile Virus

According to the CDC and WHO, West Nile virus (WNV) is the leading cause of mosquito-borne disease in the continental United States and is commonly found in Africa, Europe, the Middle East, North America, and West Asia. As a result of periodic epidemics, WNV activity typically occurs during the summer months and into the fall. All residents and visitors to areas where WNV activity has been identified are at risk of WNV infection, particularly people who engage in outdoor work and recreational activities. It is estimated that approximately 1 in 150 persons infected with the West Nile virus will develop a more severe form of the disease.

Figure 1: Distribution of WNV, countries with historic or recent (2007-present) WNV activity (isolations from mosquitoes, birds, horses or humans) are highlighted in red and blue, respectively

Figure 2: Explore Human Data for 1999-2022 in the U.S.A

Figure 3: West Nile virus human disease cases reported by month of illness onset, 1999-2022, All disease cases in the U.S.A

Key facts

West Nile virus can cause a fatal neurological disease in humans.

However, approximately 80% of people who are infected will not show any symptoms, which leads to the even wider spread of the virus.

Mosquitoes become infected when they feed on infected birds. Infected mosquitoes then spread West Nile virus to people and other animals by biting them.

As of now, there are no vaccines accessible for proactive protection or medications to treat WNV in humans.

Figure 4:West Nile Virus Transmission Cycle

Signs and symptoms

Infection with WNV is either asymptomatic (no symptoms) in around 80% of infected people or can lead to West Nile fever or severe West Nile disease.

About 20% of people who become infected with WNV will develop West Nile fever. Symptoms include：

l Fever

l Headache

l Tiredness

l Body aches

l Nausea

l Vomiting

l Occasionally a skin rash (on the trunk of the body) and swollen lymph glands.

The symptoms of severe disease (also called neuroinvasive disease, such as West Nile encephalitis or meningitis or West Nile poliomyelitis). Serious illness can occur in people of any age, however, people over the age of 50 and some immunocompromised persons (for example, transplant patients) are at the highest risk of getting severely ill when infected with WNV. The incubation period is usually 3 to 14 days.

Prevention

West Nile virus (WNV) is spread to people through the bite of an infected mosquito. Mosquitoes bite during the day and night. There is no vaccine to prevent WNV infection. The best way to prevent West Nile is to protect yourself from mosquito bites. Use insect repellent, wear long-sleeved shirts and pants, treat clothing and gear, and take steps to control mosquitoes indoors and outdoors.

WNV Diagnosis

In the absence of effective treatments or vaccines, the significance of testing for West Nile virus becomes paramount. Early and accurate testing serves as a crucial beacon, allowing us to identify individuals who may have fallen victim to this insidious disease.

West Nile virus can be diagnosed by a number of different tests:

IgG antibody sero-conversion (or significant increase in antibody titers) in two serial specimens collected at a one-week interval by enzyme-linked immunosorbent assay (ELISA);

IgM antibody capture enzyme-linked immunosorbent assay (ELISA);

neutralisation assays;

viral detection by reverse transcription polymerase chain reaction (RT-PCR) assay

virus isolation by cell culture.

Some studies indicate that RT-PCR will be more useful in immunocompromised patients where antibody development is delayed or absent. RT-PCR led to sensitive, easy identification, and rapid reactions.

What can BioPerfectus provide for WNV diagnosis?

BioPerfectus offers West Nile Virus Real Time PCR Kit, designed for human diagnosis with a CE certificate. From NA extraction to PCR amplification, we could provide a Total PCR Solution for distinguishing vector-borne viruses with similar symptoms.