on our broadcast tonight, outbreak. the deadly west nile virus is spreading fast. now the feds say it's in almost every state. firestorm in california exploding across dry forest land taking a frightening toll tonight. the gathering storm. is it really possible that a hurricane could be heading to tampa and arriving just as republicans arrive for their convention? toght, the preps are under way just in case. >> risk factor. a new link between the age of some fathers and children with with autism. still making a difference. we need to update you on what's happened since we first told you about a little boy burning up the track to help others. about a little boy burning up the track to help others. "nightly news" begins now. captions paid for by nbc-universal television good evening. tonight it is official, the

federal government says the current outbreak of west nile virus is the largest in the u.s. right now there are four times the usual number of cases. what's worse is very few people are exempt from this because it's now been found in just about every state in this country. some numbers here, over 11 cases -- over 1100 cases reported in 38 states in all. texas and the lower mississippi delta area have been hit the worst. unbelievably 41 people have died from it so far. that's part of the problem, it's early yet in the west nile season. that's why the numbers from the feds today got the attention of a lot of people. we begin tonight with nbc's janet shamlian. she's just outside houston. hey, janet, good evening. >> reporter: brian, good evening. this is hooks airport. it's one of the command centers in the battle against west nile. tonight after dark planes will take off from here and spray tens of thousands of acres to battle this virus from the air.

the west nile virus spread by infected mosquitoes, has never spread across the country this far, this fast. >> this is the worst west nile outbreak in the united states. >> reporter: the cdc reports the number of cases has almost doubled since last week. more than half are in texas, where the death toll has risen to 26. >> i was feeling real drowsy, really weak and everything, started having problems breathing. i went and laid down to see if things would get better. >> reporter: in fact they got worse for domingo via. after 11 days at the baylor medical center, he's home, but walking with a cane and he still has blurry vision. >> they said i will get better but it's going to take some time. >> reporter: dallas, which has most cases, has mounted an after dark aerial attack, small planes spraying insecticide deemed safe by the epa. >> we're passing out brochures about west nile virus. >> reporter: on the ground an information campaign.

standing water has become public enemy number one. it's prime breeding ground for mosquitoes. >> what we have right now is a very serious outbreak here. what we need to do is interrupt the transmission cycle as quickly as we can to try to save lives. >> reporter: 80% of people infected will have no symptoms. dr. nancy snyderman says for others, the virus can progress quickly. >> symptoms occurring 10 to 14 days after a bite. they are usually mild. fever, rash, exhaustion. if there are neurologic problems, confusion, seizures, or if you're over the age of 70, that's when you get to the hospital. >> reporter: experts say the numbers will rise because the west nile season is young, not ending until late september. and the numbers are already rising. texas health officials just updated the death toll here in the lone star state. it's now at 28. two more people have died. >> unbelievable numbers. janet shamlian starting us off outside of spring, texas. just outside houston tonight. janet, thanks.

now to the question we posed at the very top of the broadcast. is it possible a hurricane could be headed for tampa, florida, just as republicans head for tampa, florida, for their gop convention. forecasting this far out is kind of like forecasting the outcome of the general election but here is what we do know. there are hurricane watches and warnings throughout the caribbean. tonight the u.s. navy has put forces at guantanamo on alert, evacuating hundreds of people off that base in cuba and a lot of wary floridans, veterans at this, are watching this very closely as is jim cantore at weather channel headquarters. good evening. >> reporter: good evening. each night confidence grows for a storm that's going to come through the caribbean and turn toward the southeast united states. of course, florida would be first in through here. the situation got complicated tonight because the initiation from the hurricane center at 5:00 in their advisory, we have multiple centers, multiple clusters of thunderstorms which could actually take over as the main center.

you see the one i've drawn here is the one they are using. that means, so what are we initializing here? that's going to have big impacts on what will eventually be the future track of this. again, a lot of confidence in the westward track. you mentioned the hurricane warnings and the watches that are out for puerto rico and dominican and haiti. regardless of strength, there are going to be big impacts here in terms of flooding, because this is such a large storm already, it will rain for days. then as we get into sunday night and monday, florida very, very much in that cone. unfortunately i think we're going to be seeing a whole different animal than what we see now. regardless of what we're starting with, brian, i think the confidence is high enough we'll eventually have a storm, one that could grow rather large impacting the united states next week. >> all right, jim. of course, we'll stay at this as both the storm and the convention approach. jim cantore, weather channel headquarters. in northern california tonight, more than 2,000 firefighters are working a dangerous, unpredictable fire that started this past weekend. some of them, along with our own correspondent miguel almaguer,

found themselves in the path of monstrous flames today when the edge of the fire made a fast run right at them, at the worst possible time. miguel reports tonight from the fire line. >> reporter: exploding across forest land, moving towards homes, northern california's ponderosa fire blew up this afternoon. >> coming hot and hard. >> reporter: firefighters scrambled, 50 structures have been destroyed, 240 more threatened. with help from a steady air attack and aggressive push on the ground, crews have contained half this blaze. but flair-ups forced firefighters to retreat. breeding on dry forest land for five days now, this fire continues to make runs. crews are worried the next one will be into a neighborhood. this afternoon the mountain town of mineral was placed under voluntary evacuation. at this christian campground,

most of the 200 people are seniors. >> if you do have to leave, we want you to be able to do it and be able to get out safely. >> reporter: dangerous and deadly, this wildfire season is also historic. in new mexico, the largest in state history. in colorado, the most destructive. twelve firefighters have died this season. the west under siege, a fire season for the record books. miguel almaguer, nbc news, california. >> now to the economy in the news today that gave us the clearest, most vivid evidence yet of what a brutal decade this has been for middle class americans who have found themselves losing ground economically. in fact, the middle class itself is shrinking. our report tonight from nbc's john yang. >> reporter: the american middle class, the historic backbone of the u.s. economy, is struggling through a lost decade, losing

ground and shrinking in numbers. that's the conclusion of a new report from the pew research center, which found that in the past 10 years family incomes at all levels have declined. the first time that's happened since the end of world war ii. >> there are fewer people in the middle now than there used to be. they have a smaller share of a shrinking pie. >> reporter: not only did incomes fall but so did median wealth. what people own minus what they owe. it went from about 130,000 in 2001 to around $93,000 in 2010. who do middle class americans blame for this? in a survey 62% said congress. 54% faulted banks and financial institutions. 47% said big corporations. >> only 8% blame the middle class itself. they see this as a problem being imposed upon them by large institutions. >> middle class americans are also getting more pessimistic about the future. only 43% say their children will have a better life than their

own, down from 51% just four years ago. as people say they are working harder and harder just to stay even. john yang, nbc news, chicago. on the campaign trail today, congressman todd akin continued what's being called his apology tour for his remarks about rape and abortion after inflicting unforeseen and great damage on the national party. but there is more to report tonight. nbc's andrea mitchell has that story. >> reporter: mitt romney in iowa, paul ryan in north carolina. today both zeroing in on the economy. but because of todd akin only days before their convention, republicans remain trapped in a national debate about abortion and rape. >> it's been an exciting day. >> we're doing the best we can. >> reporter: on "today," akin told matt lauer he misspoke, does not believe in so-called legitimate rape. >> while i apologize for the

misuse of that word, at the same time i don't apologize for the fact i am strong in my belief of pro-life. paul ryan co-sponsored one bill with akin that critics say could outlaw all abortions even for rape victims. today he said he would follow mitt romney's lead. >> mitt romney as president, he sets policy. his policy for rape, incest, health of the mother. i'm comfortable with it. it's a good step in the right direction. >> romney once supported abortion rights. he reversed course before his first run to the white house. in 2007 he embraced anti-abortion activist dr. john willke, the man who came up with the discredited rape theory akin was citing, a theory he cited two days ago saying rape victims were unlikely to get pregnant. saying, quote, this is a traumatic thing, she's uptight, frightened, tight and so on. sperm are less likely to be able to fertilize. not what mitt romney wants to focus on. >> mitt romney took pains to make sure he never talked about abortion, whether to me or

others. he just didn't want to have anything to do with it. here he is having to talk about it. >> meanwhile democrat claire mccaskill now has a chance. i'm going to run against todd akin and we're going to draw the contrast necessary so voters know he's outside the mainstream. >> reporter: if republicans thought they could escape the platform committee has adopted a strong anti-abortion plank with no exception for rape victims. but the important thing for voters, mitt romney has clearly made it clear he disagreed entirely with todd akin's view. >> in our nbc newsroom, andrea, thanks. this week the american death toll in the war in afghanistan passed 2,000. it long ago became this nation's longest war. lately an increasing number of americans have been killed at the hands of afghan security forces. our chief foreign correspond richard engel, who has spent so

many years of his life covering this war is here with us in our studio tonight. richard, we were struck by this. today's "new york times" comes out with what is, in effect, the second thousand american troops to die out of the 2,000 in all in this war. it is striking and arresting as a visual. i just looked down and saw a kid from my hometown in new jersey. all of them leave family members behind. question to you as a veteran covering this, how does this end? >> well, there's a surge under way. the surge is ending right now. by the way, i think it's a very bold move from the "new york times" to do this, because no one has been focusing on afghanistan. no one has been focusing on the surge that is under way right now. casualty figures are up. the surge is ending. if you ask the military, the surge has been a success and the surge will allow the roughly 80,000 troops who are there to leave the country in two years, in 2014. if you ask many afghans and you ask many people in this country

and you look at the absence of debate, they would say the surge did not work, that u.s. troops are going to leave sometime at the end of 2014 and afghanistan will be a failed state with some sort of extremist president. >> we know your travels will take you back here again before too long. richard engel here with us in the studio. thanks. today we learned a former member of navy s.e.a.l. team six has written a book about the bin laden raid. the book is already raising a lot of eyebrows in the special operations community where they decidedly do not talk about their work, which may explain why this book titled "no easy day" is being written under an anonymous, made-up pen name. it will be released on september 11th. the pentagon says the author is no longer on active duty. still ahead as we continue tonight, news about autism, specifically this. does the age of the father increase the risk to the children. later, look at him now. what's happened since we first met one very determined kid

racing to help others in the fight of their lives.

it is an arresting headline that came out today, older fathers are more likely to have children who are autistic. our chief science correspondent robert bazell has more on the new research suggesting men may, too, have a biological clock. >> reporter: it's the strongest evidence yet that older men run a higher risk of fathering children with autism and other mental problems. the study out today is published as the cover story in the prestigious journal "nature." >> it helps us understand the complex causes that are likely behind autism and other related developmental disorders.

>> reporter: research has shown for each decade a man ages, his chance of fathering a child with autism goes up by 22%. today's study in the laboratories in iceland offers a good explanation. it shows that as men age, the sperm cells undergo genetic mutations which are passed onto the child. a 20-year-old man passes on an average of 25 mutations, while a 40-year-old passes on 65. the number keeps going up as the man gets older. many scientists caution while this latest research is very important, a father's age is just one of many factors that increase the risk for autism. often young men have children with autism. even though the average age of fathers has been increasing, it still only accounts for a small part of the recent big jump in autism cases. >> for a father who is over 50, if you look at the risk factors contributing towards autism, all the other risk factors are more important than the risk caused by these mutations. >> reporter: the other risk

factors for autism, older moms also have a greater risk, family history and premature birth play a role. autism remains a frightening puzzle with many of the pieces still missing. robert bazell, nbc news, new york. up next here tonight, dr. martin luther king, jr., in his own words in the lost tape we have not been able to hear until now.

the latest picture from mars is just a photo of tire tracks on mars, but roll that thought around in your head for a while. those are tire tracks on mars from a vehicle nasa landed there, the new mars rover curiosity taking its first tentative test-drive around its new neighborhood. by the way, they have named the landing site bradbury after the late great ray bradbury of science fiction fame, who would have turned 92 today.

sadly, he did not live long enough to see this. a piece of american history we did not know we had has been discovered in a box in an attic in chattanooga, tennessee. it's reel to reel audiotape of an interview with the reverend dr. martin luther king, jr. the best thing we can do here is let you listen to a portion of what dr. king said about the progress toward civil rights. as a young man of just 31 years of age, this was recorded just four days before christmas, 1960. >> i'm convinced that when the history books are written in future years, historians will have to record this movement as one of the greatest epics of our heritage. i think the movement represents struggle on the highest level of dignity and discipline. no one of goodwill can disagree with the ends of the sit-in movement, the end to break down

all the barriers between people on the basis of race, color. >> the quality and clarity are perfect. in case you're wondering, the interview was recorded by a local insurance salesman who wanted to write a books on racism. it also contains rare comments by dr. king on the situation in africa right then. we put the complete audio on our website for you tonight. up next this evening, a little boy using a lot of speed to make a big difference.

time now for our making a difference report and an update on a story we've been following for a while. a young boy with drive in every sense of the word working to speed a cure for childhood cancer and making a difference along the way. his story tonight from nbc's anne thompson. >> reporter: this summer mini tyrrell is in overdrive in his race thelp children with cancer. >> cancer is just -- i don't like it. i wish it wasn't a subject in the world. >> reporter: this virginia go-cart driver combines his 7-year-old logic -- >> a raffle or something?

>> reporter: -- with the marketing savvy of an adult. >> my hope is that i will inspire each one of you here to make a difference. >> reporter: he already has. most drivers chart their success with points or prizes, for mini, it's donations. this year he has a new goal, $250,000. when we first met mini last october, inspired by his friend ella, he raised $7,000. >> i'd like to present a check for a lot of money. >> all i can say is you look fast. >> reporter: nascar legend jeff gordon pledged to match that. the total today $34,000 and growing. the money at this rate goes to help a young man mini has never met, who must travel four hours for treatment. >> he now considers this his job. he says this is my job. i'm racing go-carts, and i'm raising money for kids cancer. >> reporter: robin major is so glad he does. four years ago her daughter maddie, then just three, was diagnosed with leukemia. she endured two and a half years

of chemotherapy, a relapse and bone marrow transplant that made maddie cancer-free. >> crying. >> why do you think your mom is crying? >> because she's happy. >> reporter: the odyssey devastated the family's finances. when they needed to repaint the house so maddie with a weakened immune system could come home, mini's mission came to the rescue. >> sometimes that makes all the difference in the world, just knowing there's that one person who cares enough to say, hey, you need a gallon of paint. let me provide that for you. >> reporter: today mini is children's foundation, taking his experience with jeff and replicating it for kids with cancer. at an age when most children are easily distracted, mini knows exactly where he's going. anne thompson, nbc news, virginia. >> nice thought to end on for a wednesday night. thank you for being here with us. i'm brian williams.

of course we hope to see you right back here tomorrow evening. right back here tomorrow evening. good night. -- captions by vitac -- www.vitac.com right now at 6:00, one of the most violent stretches in recent memory. >> i'm tony cove less ki. you've seen the pictures and the video. a massive road en infestation. what it did and why. first the giants and now the a's. reaction tonight as another local baseball star is busted for drug use.