By Marice Richter

DALLAS, Oct 31 (Reuters) - The number of people infected with the mosquito-borne West Nile virus in the United States continues to grow, but the pace of this year's outbreak is slowing, federal health officials said on Wednesday.

The Centers for Disease Control and Prevention said 4,891 people have contracted the disease, up from 4,725 a week ago. The virus killed four more people in the past week, bringing this year's death toll to 223.

The outbreak appears to be slowing, with 166 new cases reported during the last week, down from 199 the week before, according to CDC data. The week's death toll dropped to four, down from 36 during the previous week.

Just over half the cases reported to the CDC this year have been of the severe nueroinvasive form of the disease, which can cause meningitis and encephalitis. West Nile Fever, the less severe form, causes flu-like symptoms and is rarely lethal.

More than 70 percent of cases have been concentrated in 10 states: Texas, California, Louisiana, Mississippi, Illinois, South Dakota, Michigan, Oklahoma, Nebraska and Colorado.

Texas has been the hardest hit, accounting for more than a third of all cases, with Dallas-Fort Worth at the center of the outbreak.

According to the latest tally from the Texas Department of State Health Services, 1,718 people in the state have contracted the virus this year, and 78 people have died.

"We're still seeing new cases, but we're seeing the pace slow down quite a bit," said Chris Van Deusen, a spokesman for the Texas Department of State Health Services.

CDC officials said warm weather is a factor in a West Nile outbreak and colder weather suppresses mosquito activity. The worst year for West Nile-related deaths was 2002, when 284 people died as a result of the virus, the CDC said. (Editing by Cynthia Johnston and Stacey Joyce)

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  • Ice

    A shock of cold therapy will provide relief for itching and keep you from swelling more, says Schultz. "Ice actually numbs the nerves that conduct itching and pain so you don't feel either," he says. <br><br> You may have heard that going the other direction in temperature can also help. Hot water would in fact have the same effect on the nerves, says Schultz, but after you remove your warm compress or step out of that hot shower, you'll face a "rebound release of histamine that makes the itching worse," he says.

  • Essential Oils

    "Tea tree oil is one of my favorite essential oils in all of dermatology," says Schultz. It <a href="http://tlc.howstuffworks.com/family/treating-insect-bites-with-aromatherapy.htm" target="_hplink">acts as an anti-inflammatory</a>, so it can combat itching, swelling and pain, and it seems to also have anti-bacterial and anti-viral properties that can help prevent infection at the site of the bite, he explains. <br><br> Lavender oil can also help. "Lavender is the most versatile of all the essential oiils, with more benefits than you can shake a stick at," says Schultz. A dab on the skin can help reduce inflammation and pain and prevent infections, he says. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/badlydrawn/4685088481/" target="_hplink">.angels.</a></em>

  • Vinegar

    This "way-underutilized" home remedy can help stop itching due to its acidity, says Schultz. He recommends diluting two or three cups in a bathtub of warm water to treat all-over bites, or putting a few drops on cotton and wiping an individual bite. Apple cider vinegar may be an even better bet, he adds, since it's slightly less acidic, and it's likely that the pH of itchy, red skin is off balance to begin with, he says. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/aroberts/4080080785/" target="_hplink">AndyRobertsPhotos</a></em>

  • Honey

    Since this natural sweetener is known for a <a href="http://www.everydayhealth.com/diet-nutrition/8-health-benefits-of-honey-for-a-happy-new-year-sd.aspx" target="_hplink">wide range of health benefits</a>, including its anti-inflammatory and anti-bacterial properties, it's not surprising that honey can also ease itchy bites. It's included in a number of natural lotions and balms for this exact reason, Everyday Health explains. <br><br> Schultz recommends opting for raw honey and only dabbing a little bit right on the bite. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/dphiffer/79606170/" target="_hplink">dphiffer</a></em>

  • Tea Bag

    Just like (cooled!) tea bags can <a href="http://www.huffingtonpost.com/2012/04/12/allergies-skin-problems_n_1418961.html" target="_hplink">reduce under-eye puffiness</a>, they can ease swelling on bites, too, says Schultz. The tannins in tea act as an astringent, he says, drawing extra fluid out of the bite.

  • Baking Soda

    "Sodium bicarbonate is a mild alkaline compound that <a href="http://www.prevention.com/doubledutyremedies/list/3.shtml" target="_hplink">can help neutralize the pH balance of your skin</a>," Dr. Linda K. Franks told <em>Prevention</em>. "This 'buffering effect' may help quell the inflammation that occurs at the skin's surface, easing your soreness." <br><br> Try dissolving some into a warm bath and soaking for 30 minutes, or mixing some with a little water to create a paste to apply directly to the bitten skin. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/f-oxymoron/5423065696/" target="_hplink">[F]oxymoron</a></em>

  • Witch Hazel

    Baking soda can also work in conjunction with other remedies, says Schultz, like this plant-based astringent that, when applied in a paste with baking soda, will draw fluid out and reduce swelling at the bite. "There's a synergy, they work even better together," he says. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/zimpenfish/7074564449/" target="_hplink">zimpenfish</a></em>

  • Basil

    The aromatic leaf naturally <a href="http://www.ncbi.nlm.nih.gov/pubmed/18401780" target="_hplink">contains camphor and thymol</a>, two compounds that can relieve itching, says Schultz. It's easy to crush some up and apply it to bites, or buy the essential oil and dab onto the skin. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/saragoldsmith/2541929711/" target="_hplink">saragoldsmith</a></em>

  • Lemon And Lime

    Both citrus fruits are anti-itch, anti-bacterial and anti-microbial, according to Schultz. The juice or the peel can "kill all sorts of bacteria" he says. <br><br> There is one downside, though. Just the way you used to squeeze lemon juice into your hair for beachy highlights, the oils will also react with the sun on your skin. "You'll get a blistering reaction," Schultz says. Stay safe by only using citrus-based remedies indoors. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/psd/2873520174/" target="_hplink">psd</a></em>

  • Peppermint

    You may have heard that a dab of toothpaste can ease the itch, but it might be that minty-fresh flavoring that's at work. <br><br> "It causes a cooling sensation, [which] gets to the brain faster than the itching," Schultz says. Because the brain can only process one sensation at a time, cooling agents are often added to skin products to act as "counter-irritants" he says, which prevent and block other sensations, like itching. If you don't want to slather the chemicals in your toothpaste on your bites, try a drop of the essential oil or a paste made from crushed leaves.

  • Banana Peel

    While some people swear by this home remedy, there (perhaps unsurprisingly) isn't a whole lot of credible research to back it up. Schultz hypothesizes that the sugars in the chemical makeup of the skin of a banana could be soothing and draw fluid out from a bite. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/carbonnyc/7171600976/" target="_hplink">CarbonNYC</a></em>

  • Milk And Water

    For a soothing compress, Schultz recommends soaking equal parts milk and water into a handkerchief and applying it to the skin. "It's very soothing and helpful at relieving itching, swelling and inflammation," he says, "plus it's also a great technique for relieving sunburn." Skim works the best, he adds, as it's the protein and not the fat in milk that soothes the skin. <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/elements/3937169441/" target="_hplink">tauress</a></em>

  • Slapping Or Pinching

    It sounds silly, but it works! "Slapping is a greater form of pain than itching," explains Schultz. "It's more startling, but it's not annoying the way itching is." The brain can only register one feeling at a time, he says, so you may get some relief from the itchiness when the pain of a slap takes over, even if you might feel strange inflicting that pain on yourself. <br><br> Squeezing the bite gently but firmly is another option (which may feel less 'out there'). These methods can ease all itchy bumps, adds Schultz, not just mosquito bites.

  • Aloe

    While it's primarily thought of as sunburn relief, aloe shouldn't be ignored in treating bites, says Schultz. "It's very good for itching and swelling and really is very soothing." <br><br> <em>Flickr photo by <a href="http://www.flickr.com/photos/veggiefrog/2252234971/" target="_hplink">veggiefrog</a></em>

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