Experts say a Maryland man who died last month of rabies might have been spared under transplant recommendations that hadn't yet been published when he got a kidney from an infected donor in 2011.

The guidance from the federally funded United Network for Organ Sharing came out in June, nine months after organs from the Florida donor went to four patients. The guidelines urge caution when considering donors with encephalitis, a brain inflammation that is one symptom of rabies. The Florida donor suffered from the condition.

The only other known U.S. case of rabies transmission through a transplant occurred in 2004 in Texas. Four organ recipients died, and the case helped stir the creation of a UNOS committee dedicated to reducing disease transmission through transplants. The Disease Transmission Advisory Committee was formed in 2006 as part of a government agreement with the private group, based in Richmond, Va.

The committee says it took so long to publish the encephalitis guidelines partly because it had to gather and analyze enough data about rare transmission events to provide a solid basis for its recommendations.

The committee also decided to address more common diseases first.

In 2010, it issued guidance on influenza, suggesting that lungs and intestines from donors infected with the H1N1 virus not be recovered for transplant. In 2011, the panel published guidance on the cancer-causing HTLV-1 virus, and last November, recommendations on tuberculosis. The group now is working on guidance for West Nile virus.

The encephalitis document urges organ banks and transplant surgeons to be cautious in considering organs from donors whose symptoms suggest a central nervous system infection, such as rabies. It urges "extreme caution" when the encephalitis appears to be from a virus. The document lists the rabies virus as one possible cause of encephalitis.

When the donor — 20-year-old William Edward Small — died in September 2011, doctors at Sacred Hearth Heath System in Pensacola, Fla., thought his symptoms were caused by a food-borne toxin, ciguatera, carried in saltwater fish, said Kathy Giery, director of LifeQuest Organ Recovery Services, which approved his organs for transplant.

She said nobody suspected the donor had rabies until after the Maryland recipient died. If they had, the organs wouldn't have been offered, she said.

"The guidelines from 2012 were different from what was in place in 2011, when this took place, so for our cases today and going forward, I think everyone would be looking at this through a different lens," Giery said.

Dr. Michael Green, a University of Pittsburgh pediatric surgeon and chairman of the Disease Transmission Advisory Committee, said a concern for rabies in potential donors would call for extreme caution. But he said every transplant carries risk.

"In every instance, the transplant team must weigh the rare risk of donor disease transmission against the possibly greater risk that a candidate will die without a transplant opportunity," Green wrote in an email.

Compared with other diseases, rabies is rare. It kills just a handful of U.S. residents a year. Usually transmitted by a wild animal bite, it's almost always fatal once symptoms appear. But the disease can be stopped if a bitten person gets treatment, including a series of vaccinations, soon after exposure. The people in Florida, Georgia and Illinois who also received organs from Small have shown no symptoms and are getting the vaccines.

Thirty-two other people in five states who had close contact with the recipients or donor also have been urged to get the vaccine, according to the Centers for Disease Control and Prevention.

Committee member Dr. Timothy Pruett, surgical chief of the University of Minnesota transplant programs, said deaths from transmitted diseases are horrible events — but part and parcel of the organ donation system.

"The risk of dying without an organ still is so much greater than the risk of dying with a transmitted disease, but I don't want to be cavalier about it — it's something no one wants to see," he said.

The eight years it took for the rabies guidance seems unreasonable to Jennifer Hightower of Gilmer, Texas, whose 18-year-old son Joshua was among those killed by rabies-infected transplants in 2004.

"I think it took way too long," she said. "I believe any time there's signs of encephalitis or any kind of anything wrong with the brain that they can't point to, they shouldn't use them.

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A North Carolina woman says her child's father is the Air Force mechanic whose rabies-infected organs were transplanted into multiple recipients, including a Maryland man who died.

Alecia Mercer of Trenton, N.C., said Monday that military and state health officials told her last week that William Edward Small had died of rabies in September 2011. At the time of his death, Mercer says she was told that Small died of complications from a stomach virus.

Doctors in Florida didn't test the 20-year-old Small for rabies before he died. A Maryland man who received an infected kidney died. His heart, liver and other kidney went to recipients in Florida, Georgia and Illinois.

Small had been in the Air Force for 17 weeks before he died. He was in Florida to train as aviation mechanic.

The Department of Defense said last week that the donor whose organs went to four patients had been an Air Force recruit, originally from North Carolina, who died in Florida of unknown causes.

Mercer said she wasn't surprised to learn that Small had died of rabies, and not a stomach virus, because he liked to hunt and trap animals.

"He did a lot of trapping and hunting and stuff," she said. "He did the trapping, and he didn't care what the animal looked like. He just picked it up."

Small visited a clinic at the Pensacola Naval Air Station in August 2011 for abdominal pain and vomiting and was transferred to a civilian hospital four days later, a Defense Department spokeswoman said last week.

Mercer and her 3-year-old son hadn't seen Small since December 2010, several months before he joined the military.

Mercer said the state health officials asked if she had visited Small at the hospital, but she had not. The officials didn't suggest that Mercer or her son have any treatments, said Mercer, who is pregnant.

BSIP / UIG via Getty Images

An electron micrograph image of rabies viruses. A Maryland kidney transplant patient died of rabies transmitted by the organ, federal officials say.

Rabies killed a patient who got a kidney transplant more than a year ago, federal officials said Friday. Now they are treating three other people who got a second kidney, a heart and a liver from the same donor – an Air Force recruit who apparently died of undiagonosed rabies.

The donor died in Florida, and the heart, kidneys and liver from the patient were transplanted into three other people, the Centers for Disease Control and Prevention said. The Defense Department said the donor was a 20-year-old recruit who had been in the Air Force for just under four months when he died in 2011.

Doctors did not suspect rabies killed the donor and did not test for the virus, the CDC said. "Rabies was only recently confirmed as the cause of death after the current investigation began in Maryland," the CDC said.

"Shortly before becoming ill, the donor had moved to Florida, but was a previous resident of North Carolina where it is believed the exposure may have occurred. How the donor may have gotten rabies is currently under investigation," the CDC said in a statement.

The agency is not naming any of the patients involved.

"In 2011, the donor became ill and was admitted to a healthcare facility in Florida and then died.  At that time, the donor’s organs, including the kidneys, heart, and liver, were recovered and sent to recipients in Florida, Georgia, Illinois, and Maryland," the CDC said.

Potential organ donors in the United States are screened and tested  for viruses, bacteria and other infections. But rabies isn't one of the usual microbes that is tested for, in part because the test takes too long and in part because rabies is so rare in people.

People can become infected with rabies without knowing it. It  is transmitted in saliva -- which is why animal bites are dangerous -- and blood. But vaccination after a bite can prevent symptoms. Once a patient develops symptoms from rabies, it is almost always fatal.

Bats are the most common cause of rabies infection, while raccoons, skunks, and foxes are the most commonly reported rabid animals.

"CDC’s preliminary laboratory analysis indicates that the recipient and the donor both had the same type of rabies virus—a raccoon type.  This type of rabies virus can infect not only raccoons, but also other wild and domestic animals. In the United States, only one other person is reported to have died from a raccoon-type rabies virus,' the CDC said. Genetic testing can reveal what strain of virus has infected someone and advanced testing that looks for genetic mutationscan show whether someone was directly infected by someone else.

"The three other people who received organs from the donor have been identified and are currently being evaluated by their healthcare teams and receiving rabies anti-rabies shots (immune globulin and anti-rabies vaccination)," the CDC said.

"CDC is working with public health officials and healthcare facilities in five states (Fla., Ga., Ill., Md., and N.C.) to identify people who were in close contact with the initial donor or the four organ recipients and might need rabies post-exposure treatment," the agency says.

Doctors perform 40,000 organ transplants  annually worldwide.  In 2011, a team at Northwestern University’s school of medicine estimated that fewer than 1 percent of all organ transplants also transmitted an infection.

More than 28,000 organ transplants are performed in the U.S. each year,  while more than 114,000 people are waiting for organ transplants, according to the United Organ Sharing Network. In 2011, 6,669 people died waiting for organ transplants.

Organ donors are routinely tested for hepatitis viruses, HIV, a virus called HTLV that can cause leukemia, the syphilis bacteria, West Nile virus and the parasite that causes Chagas disease. But other infections have been transmitted by organ, tissue and other transplants – including  the deadly brain disease called Creutzfeldt Jakob disease or CJD; herpes, cytomegalovirus and a variety of bacterial and fungal infections.

Rabies is also known to have been transmitted both by cornea transplants and organ transplants – most recently a batch of three organ recipients treated at Baylor University in Texas in 2004. Officials ended up treating hundreds of people who had been in contact with the organ donor and the recipients.

But last August, Melissa Greenwald,  chief of the Tissue and Reproduction Branch at the Food and Drug Administration raised concerns about the lack of a systematic protocol for testing organs and tissue used for transplant.

“Disease transmission through organ and tissue transplantation has been documented. Recognizing emerging infectious diseases in organ and tissue transplantation is challenging because of nonstandardization of donor evaluations and data collection, pathogen characteristics, and recipient surveillance,” Greenwald and colleagues wrote in Emerging Infectious Diseases.

“Because organs, cells, and some tissue grafts cannot be subjected to sterilization steps, the risk of infectious disease transmission remains and thorough donor screening and testing is especially important.”

Organ recipients are especially vulnerable because they’ve usually been ill for along time, and then must take drugs to suppress their immune systems so their bodies will tolerate the donated organ.

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Frederick A. Murphy / CDC handout via EPA file

A new virus that appears similar to rabies, but has the symptoms and lethality of Ebola, shown here, has been dubbed the Bas-Congo virus. It killed two teenagers in the Congo in 2009.

A virus that killed two teenagers in Congo in 2009 is a completely new type, related to rabies but causing the bleeding and rapid death that makes Ebola infection so terrifying, scientists reported on Thursday. They’re searching for the source of the virus, which may be transmitted by insects or bats.

The new virus is being named Bas-Congo virus, for the area where it was found.  Researchers are finding more and more of these new viruses, in part because new tests make it possible, but also in the hope of better understanding them so they can prevent pandemics of deadly disease.

The virus infected a 15-year-old boy and a 13-year-old girl in the same village in Congo in 2009. They didn’t stand a chance, says Joseph Fair of Metabiota, a company that investigates pathogens. Fair is in the Democratic Republic of Congo now, under contract to the U.S. Agency for International Development (USAID) to help battle an ongoing Ebola outbreak.

“They expired within three days,” Fair said in a telephone interview. “It was a very rapid killer.”

A few days later a male nurse who cared for the two teenagers developed the same symptoms and survived. Samples from the lucky nurse have been tested and it turned out a completely new virus had infected him, Fair and other researchers report in the Public Library of Science journal PLoS pathogens.

The genetic sequences went to Dr. Charles Chiu, of the University of California, San Francisco.

“We were astounded that this patient had sequences in his blood from a completely unknown and unidentified virus,” Chiu said. They weren’t expecting that.

“Congo is very much known for having Ebola and Marburg outbreaks. Yet about 20 percent of the time we have hemorrhagic fever outbreaks that are completely negative, which means unknown causes and they are not Ebola.”

The sequencing puts this new virus on its own branch of the bad virus family tree -- somewhat related to Ebola and the virus that causes Lassa fever, another horrific killer, and most closely related to the rhabdoviruses. This family usually only infects animals with one notable exception -- rabies.

But rabies is not known to cause hemorrhaging. It’s plenty horrible on its own, of course, killing virtually all patients if they aren’t vaccinated soon after infection. 

A nurse who took care of the first infected nurse had antibodies to the new virus. It doesn’t look like the teenagers infected one another, says Fair, but they probably infected the first nurse, who probably infected the second. Tests of other villagers have found no more evidence of the virus, however, which is good news.

“Although the source of the virus remains unclear, study findings suggest that Bas-Congo virus may be spread by human-to-human contact and is an emerging pathogen associated with acute hemorrhagic fever in Africa,” the researchers wrote.

Africa is loaded with nasty viruses. Lassa fever virus comes from a family known as arenaviruses and causes 500,000 cases of hemorrhagic fever a year. Crimean-Congo hemorrhagic fever and Rift Valley Fever viruses are in another family called bunyaviruses; Ebola and Marburg viruses are filoviruses that kill anywhere between 30 percent and 90 percent of victims. They’re also helping wipe out great apes such as gorillas in Central Africa. This adds a new one to the list.

It worries Chiu because its closest relative is spread by biting flies in Australia. “We think that is potentially a valuable clue. This virus may have come from an insect vector,” Chiu says. “What is scary about this virus is if it does happen to be spread by insects, it has the potential to be something like West Nile."

West Nile showed up in the United States for the first time in 1999, having never been seen here before. It causes regular outbreaks in Africa and parts of Europe, however, and some experts think a mosquito or an infected person carried it on a flight to New York. It’s killed 147 people in an especially bad U.S. outbreak this year, although more than 90 percent of people infected with West Nile never even know it.

New viruses often cause disease -- there was severe acute respiratory syndrome or SARS, which killed 800 people and infected 8,000 in 2003 before it was stopped. Scientists are now watching a similar virus that has emerged in the Middle east.

Chiu says there is not enough information to know how deadly the new Bas-Congo virus is.

“It  has probably been lurking out there in remote areas and causing sporadic cases of hemorrhagic fever and no one had the resources to discover it,” Chiu said. “This is probably the tip of the iceberg. I believe there are many, many more of these emerging viruses that have yet to be discovered,” he added.

“This points to the importance of being vigilant, especially these remote areas of Africa and Asia. This is the area that I believe the next generation of emerging viruses will come from.”

Fair agrees, and says his team will be looking. They’ll also be checking to see if bats or insects can spread it. “It is a frightening prospect. That is why the next step in this process is to look for the vector,” Fair said.

That’s not so easy. Fair’s team and hundreds of other scientists have been looking for the reservoir -- the animal or insect source --of Ebola. That would be a bat or other creature that can carry it without getting sick itself. So far they have had no luck, although fruit bats are a major suspect.

And for the new Bas-Congo virus, the trail is now three years old. “Everything we do will be as a forensic investigation,” Fair said. “We really have to go look for a needle in a sack of needles.”

And in the meantime, there’s an outbreak of Ebola to cope with. Fair says a coordinated effort is going on, although this isn’t the worst outbreak he has seen. It’s killing about 30 percent to 40 percent of patients -- not nearly as bad as some strains, which killed up to 90 percent of victims.

“If you had to get Ebola, this is the strain to get,” he said.

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• Health teams face real-life horror in Ebola battle
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It’s been a wild year for rabies in the U.S, with rising reports of the disease in animals -- think rabid skunks, bats, even beavers -- just as supplies of the vaccine used to treat humans for the deadly virus are down.

“We’ve had essentially a lack of a winter, a very warm summer and reports of animal rabies are up,” said Jesse Blanton, an epidemiologist with the Centers for Disease Control and Prevention.

Though no firm figures are available, Blanton estimates that the number of rabid animals confirmed in the U.S. will reach the upper margins of the 6,000 to 7,000 typically found in a year. In 2011, the number barely topped 6,000.

“We had a much earlier start to the bat season this year,” he said. “It was a month early in some places. It’s really been across the board.”

No human cases of rabies infection have been reported in the U.S. this year, though six cases were reported in 2011, a high number in a country that typically sees only one or two. Three of those cases were in people who had contact with rabid animals in other countries.

But the number of human exposures to rabid animals seems to be higher this year, even in a country where up to 100 cases of possible contact may be reported across the nation on a typical summer day. And some of the cases have been sensational enough to make headlines:

• In May, an Arizona man killed a rabid mountain lion with a skillet after the big cat attacked the family dog on a hiking trip. 
• In July, a Maryland woman was kicked in the face by a rabid deer. 
• Last week, a rabid beaver jumped from a pond and chased children in Virginia, just days after a rabid beaver attacked an 83-year-old woman.
• And, in a more typical encounter, an 82-year-old woman in Wayne, Pa., was attacked Saturday in her backyard garden by a rabid skunk.

“It’s been a more intense summer for reports of human contacts,” Blanton said. However, the increased contact comes just as the two manufacturers of rabies vaccine in the U.S. -- Novartis and Sanofi Pasteur -- are reporting limited supplies and no clear date for resolution.

CDC officials have stopped short of calling the problem a shortage, but there’s no question supplies are thin. The agency reported last week that Novartis’ RabAvert, a rabies vaccine for pre-exposure use, is available only from wholesale distributors who already had existing stock. And the CDC advised that while supplies of vaccine for post-exposure prophylaxis, or PEP, remain available, health officials should make sure that rabies shots go only to those who need them.

“It’s a little worrisome. It makes us even more cautious,” said Dr. Paul Ettestad, New Mexico’s state health veterinarian. “Usually we keep enough vaccine on hand for 10 people and right now we have enough only for three or four.”

Sixty people in New Mexico have had to be treated this year with rabies post-exposure prophylaxis, or PEP, after coming into contact with rabid animals, including domestic pets, Ettestad said. An outbreak of the disease that began in December has been concentrated in Eddy County in the south part of the state.

Typically, between 30 and 70 people are treated in New Mexico in an entire year with the PEP series that includes a dose of human rabies immune globulin and four doses of vaccine given over two weeks.

Overall in the U.S., between 23,000 and 38,000 people receive PEP vaccinations after confirmed or possible exposure to rabid animals each year.

This year's combination of high demand and low vaccine supply has created sporadic problems across the country, said Blanton.

“A crimped supply is a good way to refer to it,” he said. “Largely it appears to be a short delay that happened within the distribution chain of the vaccines.”

That means that although there may be enough rabies vaccine to go around, it may take longer or be more complicated to get it. In Illinois, for instance, several providers had difficulty acquiring rabies vaccine PEP for patients with rabies exposure, according to Melaney Arnold, a health department spokeswoman. 

CDC officials said they believe the smoother distribution will resume soon, but the American Society of Health-System Pharmacists, which tracks the nation’s drug shortages, reported that neither Novartis nor Sanofi Pasteur could estimate when the products would be available.

This isn’t the first -- nor the worst -- “crimp” in the supply of rabies vaccine. An outright shortage in 2009 rippled through the rabies community, forcing states to implement secret passwords to gain access to vaccine and leading to a reevaluation of how many doses of vaccine were actually needed to prevent infection. In 2010, the CDC's Advisory Committee on Immunization Practices, or ACIP, agreed to reduce the number of doses from five to four.

The situation is not that dire now, but health care providers are urged to closely evaluate rabies cases before prescribing vaccine.

“We’ve never had the recommendation that there’s carte blanche that everyone needs to be vaccinated,” Blanton said. “We are expecting a normal, healthy, cognizant person to be aware if they had contact with a bat.”

In practice, however, determining whether contact actually occurred is harder than it seems. In Kentucky earlier this year, state health officials had to interview more than 260 people who worked as volunteers at a charity service organization and wound up sleeping in an old schoolhouse infested with bats.

“We categorized everyone as low risk, moderate risk or high risk,” said Dr. Kraig Humbaugh, the Kentucky state epidemiologist. “Instead of a blanket recommendation, we were being judicious with our vaccine administration.”

Sixteen of the volunteers were advised to consult with their doctors about PEP because they had known contact with a bat. Others were pointed toward treatment because they’d slept in a room where a bat was found. Rabies is primarily spread through the infected saliva of an animal, usually through bites. The fear is that certain people -- those who sleep too soundly, those on medication, the disabled and children -- might not realize it if they've been bitten by a bat. Still others might not feel the sting of the bat's sharp teeth.

In 2011, two of the U.S. rabies victims didn’t report contact with bats, but both had reported waking to find bats in their bedroom. Both later developed the disease and died, a CDC report said.

When in doubt, health officials usually err on the side of vaccination, experts said. The incubation period for rabies  is typically one to three months, but it can vary widely, from less than a week to more than a year, according to the World Health Organization.

The rabies vaccine PEP is the only way to stop the infection, and only during the incubation period. After that, the horrific symptoms progress rapidly, often including fever, pain, agitated behavior, hyperactivity and hydrophobia -- difficulty swallowing and panic at the thought of water. The disease is almost always fatal.

Rabies exposure typically wanes after the first frost, said Blanton, who is looking forward to colder weather. Vaccine supplies should become more plentiful, too.

“Additional lots are already coming down,” he said. “We should be back to normal.”

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Daniel Streicker / ASTMH Press

Vampire bats in an abandoned mine in Huanuco, Peru. Researchers are investigating whether some Amazonian villagers may have survived rabies infections, which have a nearly 100 percent fatality rate.

Some Amazonian villagers plagued by vampire bats may have survived rabies infections — something that doctors thought was virtually impossible. The scientists' discovery opens hopes of eventually developing an effective treatment for the nearly always fatal infection.

A study of people living in remote areas of Peru shows that about one in 10 appears to have been bitten by rabid bats, but lived to tell the tale. Rabies is almost universally fatal, with only five documented cases of people surviving. Teams at the Centers for Disease Control and Prevention are now looking further to see if people may survive the deadly virus more often than had been believed.

“They were infected,” said the CDC’s Brett Petersen, an epidemiologist who worked on the study. What’s not clear is whether the people who survived infection ever actually got sick.

Any mammal can get rabies, and the disease causes horrible symptoms as the virus attacks the nervous system. It can make an animal aggressive and violent and can cause severe pain. Victims eventually fall into a coma and die when they can no longer breathe properly.

“Rabies has the highest case fatality rate of any conventional infectious disease, approaching 100 percent,” Petersen and colleagues wrote in their report, published on Wednesday in the American Journal of Tropical Medicine and Hygiene. People can survive if vaccinated immediately after a bite or other exposure to rabies, but there is no real treatment for infection, with very rare exceptions.

The CDC team and officials with Peru’s health ministry traveled to a remote Amazon region where vampire bats regularly feed on cattle and people. It took two days to reach the area by boat.

“Many of [the people] have very basic housing. There are no real barriers for entry to bats. The bats are able to enter the house and have easy access to people,” Petersen said in a telephone interview. The teams interviewed 92 people and got blood samples from 63 of them.

More than half said they had been bitten by a bat at least once and 20 percent said they were bitten more than once a year. The blood tests showed something startling -- seven people, or 11 percent of those tested, had antibodies against rabies. These immune system proteins were the type that can neutralize a virus.

“This shows evidence that these people were exposed to rabies virus previously,” said the CDC’s Amy Gilbert, an epidemiologist who led the study.

It's undetermined whether these seven people had actually become sick. Early symptoms of rabies infection aren’t always clear and can resemble those of a cold or flu. The incubation period can be as long as three months. It might be, Gilbert said, that they were bitten and got a very low dose of the virus, perhaps not enough to make them sick. More study will be needed to find out.

“We know that not all viral introductions into the body will lead to clinical illness,” Gilbert said. A lot depends on how much virus gets in, what part of the body, how deep a bite was, and perhaps if other germs got in at the same time.

What is certain is, rabies is very deadly. “We are still talking about 99.999 percent of cases, approaching 100 percent,” Gilbert said.

The scientists aren't sure the villagers are actually immune to rabies, so the CDC team is recommending that all get vaccinated.

“What we know is that they did develop an antibody response. We don’t know what level of antibodies will provide complete protection,” Petersen said.

More outbreaks of rabies have been reported in the region in recent years, he added.

Rabies was once a global scourge, but widespread vaccination has made it very rare in countries such as the United States. The vaccine is very effective if given before symptoms develop. That's why doctors urge anyone bitten by an animal get medical attention right away. Most US cases – and there are just one or two a year at most – are caused by bat bites.

Globally, the World Health Organization says 55,000 people die of rabies every year, with dogs the source of 99 percent of these fatal bites. Five people have survived documented rabies infections -- all young girls who were given a complex treatment called the "Milwaukee protocol," which involves putting them into a medical coma.

"Our results open the door to the idea that there may be some type of natural resistance or enhanced immune response in certain communities regularly exposed to the disease," said Gilbert. "This means there may be ways to develop effective treatments that can save lives in areas where rabies remains a persistent cause of death."

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MyHealthNewsDaily

The case of a U.S. Army soldier who died in New York after likely contracting rabies from a dog bite in Afghanistan calls attention to the risk of rabies during travel or deployment to certain countries, and the importance of administering the rabies vaccine promptly to anyone who may have been exposed to the virus, according to a report of the soldier's death released today.

The 24-year-old soldier's death, which occurred in August 2011, was the first rabies death among U.S. service members since 1974, the report from the Centers for Disease Control and Prevention said.

Unless the rabies vaccine is administered after exposure, an infection with rabies virus, which targets the nervous system, is nearly always fatal.

On Aug. 19, the solider was admitted to a New York emergency room with right arm and shoulder pain, nausea and vomiting. He tested positive for rabies. Although doctors administered an experimental treatment, the soldier died on Aug. 31.

The soldier had told family and friends that he'd been bitten by a feral dog in Afghanistan in January 2011, and had sought medical treatment, which he described as wound cleansing and injections. However, an Army investigation revealed no documentation of a reported bite wound or treatment, the CDC report said.

Twenty-nine people who were in close contact with the soldier, including health-care personnel, received the vaccine.

The case also highlights the need for the global elimination of rabies in dogs, the report said. Canine rabies is responsible for the majority of rabies deaths worldwide.

In the U.S., 45 cases of rabies were reported between 1996 and August 2011, and 10 of those cases were likely caused by dog bites. All 10 occurred overseas but were reported in the U.S., the report said.

People traveling should be aware of rabies risks, and should keep a safe distance from wild and feral animals, the report said. Travelers receiving bites or scratches from such animals should wash the wound thoroughly with soap and water, and promptly seek medical attention.

Human-to-human transmission of rabies has not been documented (with the exception of transmission through organ transplantation ), the report said, but is theoretically possible, because the virus can present in saliva and tears, along with cerebrospinal fluid and neural tissue.

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