Dr. Kevin Most: West Nile, Lyme Disease and Rocky Mountain Spotted Fever
I thought we may touch on West Nile ,Lyme disease and Rocky Mountain Spotted Fever, as the news last week about the new Asian tick has garnered some attention. Great that we are looking and tracking new ticks and bugs, but probably more important that we know what we could get exposed to now and what to look for.
Last week we heard news that a tick native to Asia, that had been found in New Jersey last summer has now been found in seven states. The tick made national news last week and is known as the Asian Long horned tick. This tick, in Asia has been noted to carry a virus that causes death in 15% of the people it infects. Now do not get alarmed, as this tick in the US has not been noted to be carrying that virus. The media made a big play on this tick being found and that it carries a deadly virus, but the whole story is that the Asian Long Horn ticks found in the US currently have not been found to carry the virus. That being said the CDC will continue to monitor the tick population for this virus.
The world is getting smaller and with world travel very common, it is only a matter of time before more insects from around the world make their way here and then spread across the country. The spread across the country is occurring a lot quicker than many thought it would, and many of these insects care bacteria or viruses with them. Stopping them at the border is almost impossible, no wall will stop them as the vector for travel may be birds, may be containers carrying imports or may be brought by an individual. We all remember the concern with the Zika Virus and the amount of mosquito abatement that was done to limit it coming into the US. In 2018 we have had no local mosquito borne Zika Transmission in the United States. However Zika is still a risk for those traveling to Central America and South America and we have had 35 cases of individuals coming back to the US with the virus after traveling to an affected area.
Our focus now should be on the insect borne illnesses that we currently are seeing and making everyone aware of what to do to prevent the illness as well as how to identify it. We are finding that insect borne illnesses are spreading and becoming much more common. Insects have been known to be vectors for illnesses that up until recently were not found in the US.
Let’s take a minute to discuss a few. We all have probably heard of Lyme Disease, this is a disease that historically had been noted in the world for over 130 years, however in the US the story is quite different. In the 1970’s a group of children and adults in Lyme, Connecticut, were found to be suffering from an illness that could not be understood. The symptoms started with a rash, swollen knees, headaches and fatigue. These patients went undiagnosed for many years with many of the patients suffering from long term illness. They called the illness Lyme but had no idea what caused it or how to treat it. In the early 80’s a researcher finally identified that this was associated with a tick bite from a deer tick and that the illness was caused by a bacteria. In the 40 years since this discovery, Lyme Disease has spread to the entire United States, with cases being reported in all 50 states.
So what is Lyme Disease. It is an infection caused by a specific bacteria, that bacteria gets into our system via a bite from a deer tick. Once bitten, individuals will often get a red raised bump at the site of the bite. This will often resolve after just a few days. This is common after any tick bite and does not indicate that you have Lyme disease. However, Some individuals may go on to develop symptoms that show that the tick bite was more than a simple bite. These symptoms include getting the classic “bullseye rash”, this rash can get quite large however it is often not painful or itchy. If that rash is noted get in to see a doctor. Patients may also note fever, chills, fatigue and body aches. Often patients just write off these symptoms and do not seek care. This is an important time to see a doctor and get treated. We have blood tests that can show us if there is an infection present as well as if you have had Lyme disease in the past.
If treatment is not initiated individuals can go on to have joint pain, joint swelling, paralysis, numbness, heart problems, eye problems, liver inflammation and meningitis.
As Lyme disease is caused by a bacteria, early identification allows for treatment with antibiotics and the sooner the treatment is started the quicker and more complete the recovery. We can treat with oral antibiotics if caught early enough, and the treatment will often last for 14-21 days. Unfortunately there are patients who continue to have some symptoms after treatment as the body continues in a state of inflammation
Obviously the goal here is prevention and early identification. Deer ticks are quite small but identifying them quickly and removing them shortly after exposure decreases your chance of infection substantially. If you happen to be hiking through a forest preserve a complete body check for any ticks is a great idea. Better yet, anyone going into a wooded area or field should have clothing that will protect them, and wear insect repellant with DEET, the DEET concentration should be 30%. Don’t forget about your dog, if they are out in an area they can bring ticks back into the house, so make sure your dog has the correct flea and tick collar. Every home should have a good set of pointy tweezers and a magnifying lens. The ticks we are talking about are quite small and often a magnifying lens is needed to aid in the removal. These are also good for removing wood splinters which happens to all of us.
So the big thing with Lyme disease is prevention, wear appropriate clothes, wear DEET and check for ticks after being out in the field or forest. If you notice a tick bite, what for any other signs or symptoms which may show up a month after the tick exposure.
The spread of Lyme disease has been fairly widespread and although it has been seen in all 50 states the site of the initial infection is not always clear.
Many may remember in 1999 the incidence of dead birds in New York that caught everyone’s attention. Shortly after that they identified that the birds had died from West Nile Virus, this was a well-known virus that had been identified in Uganda but have never been noted to be here in the United States. Within a short 3 years the virus had spread from a six county area in NY to 45 states including the west coast. Many of you may remember 2002, that was a record year for Illinois with 884 cases and 64 deaths, Illinois led the country with cases and deaths that year. This was noted to be the largest outbreak and common thought now is The idea that many people now have immunity and we are actually protected from future cases of the virus is being studied.
For this disease it is noted to be carried by a mosquito however the bird acts as the mode of transportation. Mosquito’s would infect the bird, the bird would travel and bring the virus along with it, and it traveled across the country in a very short period of time.
If you spend a lot of time outside around dawn and dusk and have had many mosquito bites, chances are that you have already had West Nile Virus infection. The vast majority of people will have an infection without any symptoms or symptoms so mild that they are not reported. The mild symptoms may include fever, headache and body aches that last a day or two. Some may even notice a rash on the trunk. The downside is about 1 in 150 people infected will have more severe symptoms which can include high fever, stupor, seizures, coma, muscle weakness and paralysis.
The first case in Illinois was noted in June, although we had mosquitoes that tested positive in May. Currently we are heading into peak time for West Nile as we see most cases in August and September. This year has been average for cases as we have had 4 human cases in Illinois as of last week. However we know it is out there as we have had 1300 mosquito batches test positive and 45 counties
The West Nile illness is caused by a virus so there are no antibiotics that treat this. There is a vaccine that is now being trialed on humans via a NIH study, so perhaps we will see a vaccine soon. Some argue why should we have a vaccine for a virus that has minimal to no impact on most patients and if we only vaccinate those who are older or with a poor immune system will the vaccine work.
Treatment is supportive measures as it is for almost all viral illnesses. We try to keep the patient comfortable, keep the fever under control for the simple cases to IV’s ventilators and treatment of secondary infections treatment when appropriate.
With no treatment to eliminate the virus in our system, prevention plays a big part. Minimizing the standing water in your yard decreases the breeding grounds for mosquitos. Wearing insect repellent is key as is staying indoors at peak mosquito times, dawn and dusk.
Although we do not live anywhere near the Rocky Mountains, another tick borne illness is known as Rocky Mountain Spotted Fever, RMSF. This is an illness caused by the bite of a tick, unlike Lyme Disease where it is always from the deer tick, RMSF can come from the bite of infected dog tick or wood tick. Symptoms for this illness often start with a fever which is followed 2-4 days later with a rash. The difficult thing about this is the rash is not always the same in every person, some may have a fine pin point rash while others may have large red blotches. Symptoms will go on to include, headache, nausea, vomiting and muscle aches. This can be a life threatening illness so early identification and treatment is needed. We can diagnose with blood tests but physicians will start treatment when they see the symptoms and associated outdoor travel or possible tick exposure. The number of cases across the US has risen dramatically in the past 8-10 years, but fortunately physicians are more aware of the disease and the need to treat quickly so the number of deaths have decreased.
The big message is, the world is getting smaller, the medical field needs to be aware of international illnesses as we will start to see more insect borne illnesses spreading. Locally what you need to know is if you have received an insect bite or been exposed to wooded area where ticks and mosquitos thrive and you have any unusual symptoms, get into the doctor. Share the timing of your exposure and the timing of your symptoms with the doctor. They may decide to do blood tests, they may treat you right away. So bottom line, do what you can to prevent any exposure with clothing and repellants, and if you have a rash and fever, get into the doctor and let him take a look at it.