Mosquito-borne diseases: when the bite packs a punch

Infectious disease is on the rise as international travel increases, temperatures climb, and mosquitoes migrate to new territories. Along with these changes come new and increasing mosquito-borne diseases, most of which can either be symptom-free or mimic other illnesses.

The truth is, not all mosquitoes carry diseases. But educating yourself and taking all the steps to prevent bites will significantly lower your chances of contracting one.

Your best defense against these disease-transmitting pests is teaming up with Western Exterminator's mosquito control experts to keep mosquitoes away from your property. If you're concerned about a mosquito problem, contact us today.

Zika virus

Zika was first discovered in African monkeys in the 1940s and later made its way to the US through travel. It’s found in tropical and subtropical regions where mosquitoes feed all day and night. Symptoms include fever, rash, and body aches, but most people that suffer from Zika don’t even realize they have it. This is alarming because the virus can also be transmitted through sex and blood transfusions. Medical professionals have not released a cure or a vaccine as of yet. 

Anyone can contract the Zika virus, but it is particularly dangerous for pregnant women as they can pass it to their unborn children. Congenital Zika can result in miscarriage or birth defects such as a misshapen head and other complications.

West Nile virus

Most people have already heard of West Nile virus (WNV), but did you know that the majority of humans that contract it are asymptomatic? Those that do feel sick have flu-like symptoms and weakness that can linger for weeks. About 1% of these patients develop invasive neurological trauma such as meningitis, encephalitis, and paralysis almost identical to polio—all of which can be fatal. 

Healthy people that contract the disease usually recover in two weeks. Those with a compromised immune system—including elderly people and organ transplant patients—are at a much higher risk and can take much longer to recover, so it’s important to take all precautions when outdoors. 

West Nile virus is transmitted to humans after a mosquito feeds on an infected bird. Over 300 species of birds are known carriers of the virus, most of which don’t appear sick. While birds aren’t known to directly spread the disease to humans, it’s important to avoid handling sick or dead birds.

Canine heartworm

Mosquitoes feed on warm-blooded animals, which in turn regulates their body temperature and aids egg production. Unfortunately, this puts our furry, four-legged friends at risk. 

Canine heartworm disease is a serious condition that can cause permanent damage to the heart, lungs, and arteries. Because heartworms are parasites, they suck up all the nutrients from inside their host. But how do they get there? Adult heartworms spew microscopic baby worms into the host’s bloodstream, which are then ingested by mosquitoes and deposited onto a new host. After that mosquito feeds, the heartworm will enter the body through the same wound where the cycle can start over again. 

Symptoms of canine heartworm don’t usually appear until the infection has spread beyond the heart. You may notice fatigue, lack of interest in food and exercise, weight loss, cough, and overall irritability. 

There is a cure for canine heartworm disease but it’s expensive and complicated, so prevention is key. If your canine companion has not been treated for heartworms, schedule an appointment with your local veterinarian so your dog can live a long, healthy life.

Malaria

Malaria is a parasite transmitted to mosquitoes through infected humans. Once inside the host, the malaria parasites invade the liver where they multiply until maturity. They then move on to the red blood cells where they battle with other cells and release daughter parasites. This is when victims begin to display the classic signs of Malaria: flu-like symptoms, profuse sweating, organ failure, convulsions, and blood and neurological abnormalities. 

Once again, this mosquito-borne disease spreads only through blood and from mother to fetus.

Dengue fever

Dengue fever is spread from infected humans to mosquitoes, which is then transmitted to healthy humans. The virus that causes Dengue is closely related to those that cause West Nile and yellow fever. Over 400 million people worldwide come down with Dengue each year, and only a fraction of those cases come to the US. According to the CDC, California and Florida reported the highest cases in 2019, and of the 200+ reported US cases, only one was locally transmitted. The rest were travel-related. 

Symptoms of Dengue fever include nausea, vomiting, rash, fever, and aches in the joints and eye sockets. However, 75% of infected people are asymptomatic. Fortunately, this virus can’t be spread from one person to another.

Eastern equine encephalitis

Eastern equine encephalitis (EEE) is spread to mosquitoes through infected horse and bird blood, particularly in the eastern United States. Confirmed cases of this virus are on the rise in several states and counties, increasing the risk of infection to critical. Experts report that EEE can be even deadlier than West Nile Virus because the mortality rate is higher and grade of infection varies. 

Encephalitis refers to inflammation of the brain, which often leads to painful headaches, fever, chills, nausea, and in severe cases, coma and death. But EEE can attack as a systemic infection, and sometimes the host doesn’t even know they’re infected at all. Brain tissue, spinal fluid, and blood tests are the only ways to confirm human cases. 

Survivors of severe encephalitis often have lasting damage to the central nervous system.

Western equine encephalitis

Very closely related to EEE, Western equine encephalitis (WEE) is also transmitted to mosquitoes through infected horses and birds in wetlands. This virus can also attack the body in two ways: neurologically or systemically. The mild form may present itself as the flu, but the neuroinvasive form can lead to confusion, seizures, coma, and death. Survivors are often left with brain damage like cognitive impairment and behavioral changes.

La Crosse virus

This virus is very similar to the rest in that symptoms usually appear flu-like, if they appear at all. La Crosse virus does the strongest damage to children because their bodies are not able to fight it off. To add to the concern, there are no known treatments or cure for the disease. Fortunately, only 1% of cases are fatal.

St. Louis encephalitis

Infected birds are carriers of the St. Louis virus, which is then passed to humans through hungry mosquitoes. The viral form, if not asymptomatic, presents as fatigue, headache, nausea, vomiting, and diarrhea. Neuroinvasive encephalitis usually occurs in elderly people, which can result in permanent brain damage or death.

How to fight the bite

Mosquito-borne diseases are preventable. Here are some ways that you can reduce your chances of becoming a mosquito’s lunch. 

Avoid peak hours

Mosquitoes are most commonly spotted in the evening and early morning hours. Staying indoors—or in a screened or netted area—from dusk to dawn will keep your family safe. However, there are species to beware of at all hours of the day, so there is never a truly mosquito-free timeframe in the warm months. 

Clothing

Unfortunately, long sleeves, pants, and socks in the summer heat aren’t realistic, but covering as much skin as possible will decrease exposure. Experts suggest wearing loose-fitting clothes, preferably pre-treated with permethrin. 

Wear insect repellent

One way to make yourself and loved ones unappetizing to mosquitoes is by covering all exposed skin with chemical DEET, picaridin, and lemon eucalyptus. This is very important while traveling. Make sure to follow the instructions on the label—particularly around children and pets—and reapply as directed. And as an added bonus you’ll also be protected from ticks, fleas, and other biting insects! 

Eliminate standing water

Eliminate wet zones around your home like shallow pools, bird baths, buckets, old tires, empty pots, and trash cans because this is where mother mosquitoes lay their eggs. 

Exercise indoors

Mosquitoes are attracted to heat, carbon dioxide on our breath, and sweat, so it’s no surprise that they flock to joggers. For those that must participate in outdoor recreation—like baseball or tennis—always wear insect repellent. 

Home repairs

Inspect all the screens in your home, including windows, doors, and screened-in sitting rooms. Replace any damaged screens and remember to keep doors closed so nothing can wander inside. 

Protect family pets

Make sure your four-legged friends are up to date on vaccines and oral medications. You may also want to consider a pet-safe mosquito repellent, but consult your veterinarian first. 

Call a professional to fight mosquito-borne diseases

If you live in a mosquito-ridden territory or see a spike in mosquitoes around your home, call the professionals at Western Exterminator for a free inspection at 888-444-6138.

For questions about mosquitoes and Coronavirus, visit our article: Can mosquitoes spread Coronavirus?