Rift Valley Fever (RVF) is a zoonotic disease that is able to spread from animals (primarily domestic ruminants like cattle, sheep, goats, buffalo, camels, and so on) to humans and vice versa. Other animals are known to be able to contract it as well, including dogs, cats, monkeys, and horses. This disease is viral, producing symptoms that typically begin as a headache, muscle and joint pains, a slight fever, and dizziness. It may then progress to a high fever, feeling as though you have the flu, and potential liver abnormalities. According to the Center for Disease Control (CDC), most people only experience slight to moderate versions of these symptoms, but about 8 to 10% of people who contract the disease may experience more severe and critical problems, such as brain inflammation, ocular disease, and potentially permanent vision loss, and, in very extreme cases, death from hemorrhaging. Pregnant women and animals are of particular concern, as the disease can severely damage the fetus and leads to an approximate 50% fetal mortality rate in cattle that are infected, with this number jumping to nearly 90% for fetal and infant sheep. To date, there are only two known cases of human infant mortality due to RVF, though doctors acknowledge that since we’re still learning about this disease, there could be more cases that were misidentified or simply not documented.
What Causes It?
As suggested by this article’s title, the Rift Valley Fever virus is typically spread by mosquitos. Specifically, it is transferred via direct contact with the tissues, blood, bodily fluids, etcetera that are infected with the virus. This can occur via touching or ingesting infected meat, aiding in livestock birthing procedures (wherein the mother is infected), and commonly, via being bitten by an insect, typically a mosquito or other similar blood-sucking insect, that is carrying the disease on its mouthparts. The insects don’t themselves become infected with the virus but instead act as carriers or vectors. There are multiple mosquito species that can spread the disease (74 known species, to be exact) after first biting an infected animal. The more rainfall there is, the more the disease seems to spread, as increased rainfall allows for increased mosquito populations. Mosquito eggs are viable for several years in dry conditions after being laid, and similarly, the virus can lay dormant in these eggs for as long as it takes them to hatch and then mature into adults.
Specifically, the virus first appeared in the Rift Valley (hence its name) in Kenya in 1931 and acts by attacking the glycoproteins within DNA. Most commonly, Rift Valley Fever occurs in sub-Saharan Africa, the Middle East, and portions of Asia. However, with modern day worldwide travel, shipping, and trade available, there is a greater risk of the disease impacting other continents such as Europe and the Americas.
How Can I Protect Myself from RVF?
If you live in Europe or the Americas, the chances of you contracting RVF are pretty low. However, if traveling to impacted areas or you just wish to be cautious regardless, there are steps that you can take to help protect yourself from the disease.
- Insect Repellent: Perhaps one of the simplest ways to help protect yourself from contracting RVF is to utilize insect repellent that will deter potential carrier insects such as mosquitos, ticks, and biting flies or gnats. Wearing long, protective clothing (long sleeve shirts and pants, hats, etc.) that covers your extremities is also helpful, as is reapplying the repellent every couple of hours or more frequently if you’re sweating or have been in the water. Be aware that some repellents, such as those with a higher concentration of DEET, have a greater likelihood of deterring mosquitos and ticks but at the expense of being hard on your skin and clothes. There are some natural options available as well.
- Avoid Some Areas: As mentioned above, the areas where RVF is of most concern is in Africa, Asia, and the Middle East, so be aware of the risks if you’re traveling to these areas. If you can, try not to travel to areas where this disease has confirmed cases, and take precautions and preventative measures if you must go into these areas. In addition, if in these locations limit time spent outside during peak insect activity times, such as during rainy seasons or particularly humid days when mosquitos are likely to be more active. Again, wear bug repellent and protective clothing.
- Good Hygiene: If you work with animals, particularly cows, goats, or sheep, or in the healthcare industry, make certain that you wear gloves and long clothing to protect yourself from any blood or other bodily fluids that you may come into contact with while working with the animal, particularly, if you work in an area that has confirmed cases of or is suspected to have RVF. In addition, wash your hands and arms regularly. If you or someone else is administering an RVF vaccine to animals, don’t do so during an outbreak but rather before one occurs if there is a risk of the disease spreading to that area – vaccinating during an outbreak can actually spread the disease more via needles.
- Thoroughly Cook Your Food: You can greatly reduce the risk of contracting RVF by carefully, fully cooking your food prior to consumption. Meat, in particular, needs to be cooked completely, and unpasteurized milk should not be consumed in risk/endemic areas. If you purchased the milk or meat from elsewhere and had it shipped to you, you will also need to be cautious.
In addition to the main points covered above, other possible steps to take include making sure that your personal lawn is well aerated. You can do this by incorporating plenty of plants to help uptake excess moisture (as the moister an area is, the more mosquitos will thrive in it), and also by tilling up your soil or simply poking some small holes throughout it to encourage faster water drainage. Other measures can include adding a section of bug netting to your patio or lawn so that you can at least still be outdoors in this area with much less worry of mosquitos getting through.