'Stomach Flu' Rips Through the Nation
By Anita Manning
USA Today
(Jan. 9) - Stomach viruses tearing through communities from California to the Carolinas wrecked the December holidays for some, and they are getting the new year off to an uncomfortable start for others.
The most likely culprits, experts say, are noroviruses, the most common cause of contagious gastroenteritis, better known as the "stomach flu." Cases occur every winter, but health officials say that in recent weeks they have seen two to three times as many cases as usual.
The virus, best known as the cause of cruise ship outbreaks, is easy to catch, hard to wipe out and seems to be everywhere at once.
Last week, San Quentin State Prison closed to new prisoners and visitors after nearly 500 inmates and guards fell ill with vomiting, diarrhea, stomach cramps, headaches and low fever. Similar symptoms have been plaguing staff and residents of nursing homes in several states. College and pro athletes have missed games. Hundreds of patients have sought help in emergency rooms since mid-December. Nearly 400 people on a Caribbean cruise last month and 700 on a trans-Atlantic cruise in November were stricken, according to Associated Press reports.
Norovirus infection usually clears up after two or three days, but medical epidemiologist Marc-Alain Widdowson, a norovirus expert at the Centers for Disease Control and Prevention, says the misery of those days shouldn't be dismissed.
"When you're ill, you're really ill," he says. "People (can) vomit 20 times a day."
Norovirus can be spread through contaminated food or water, causing large outbreaks. About half of food-borne diseases are thought to be caused by norovirus, the CDC says.
But this winter, it is spreading mainly from person to person through communities, and experts believe the majority of cases are unreported.
Once it's in the house, experts say, it's tough to wipe out. It can linger for days on surfaces such as children's toys, keyboards, telephones and doorknobs, and both vomit and stool are highly infectious. It is present in the stool up to three weeks after the patient recovers, so health officials stress the importance of hand-washing, especially after using the bathroom and before preparing food.
The virus causes illness year-round, though like many, it is more common in colder months. Why it's so widespread this winter is not known, Widdowson says. "Some years, it does seem to be a lot worse than others, and this is one of those."
From Carolina to California
Among states with outbreaks:
--Texas. In Corpus Christi, there has been "a true minor epidemic here," says William Burgin Jr., health authority for the Corpus Christi-Nueces County Public Health District. "Dozens of cases at a time were reported" during the holidays, and hundreds more likely went unreported. Hospitals saw about three times as many cases as usual. "Even our emergency room folks caught it."
--North Carolina. In Asheville, 30 to 40 people have been sick enough to seek emergency room treatment for norovirus symptoms in the past two to three weeks, and up to 10 have been hospitalized, says Buncombe County Health Center medical director Steve Swearingen. And "there's no way of knowing how many are out in the community."
--California. Twenty nursing homes in Contra Costa County have reported outbreaks, twice as many as in a normal year, says communicable-disease program chief Francie Wise. "In one facility, we had over 50 patients and 21 health care workers sick," she says.
--Wisconsin. The state Division of Public Health put out an alert to local and tribal health departments last month, says spokeswoman Stephanie Marquis. "It's hitting a lot of people all at the same time." She says outbreaks in schools led a few, including two in Oshkosh, to close before the holidays.
--Montana. Cases began in nursing homes the week before Christmas, says Yellowstone City-County Health Department spokeswoman Barbara Schneeman. "That's real typical for noroviruses. It seems they like nursing homes and cruise ships."
Six facilities have confirmed positive cases. No cases were reported last winter, she says, but there was an outbreak earlier this year. From late March to early June, "we had about 1,100 to 1,200 people reporting the norovirus to us, but we estimate for every person who reports, there are two or three who don't. That would put our numbers in the 4,000 to 5,000 range."
Outbreaks in nursing homes are of special concern because of the risk of dehydration caused by vomiting and diarrhea, health experts warn. Deaths as a result of norovirus are rare. It may be a factor in roughly 300 deaths, generally in the elderly, the CDC says.
But even the young and healthy are vulnerable. About 50 University of Missouri football players, coaches, staff and family members were flattened days before Christmas while in El Paso for a bowl game.
"It spread pretty fast," says Chad Moller, team spokesman. "When you travel in a plane in closed quarters and are around each other a solid week in a hotel," it's easy to see why, he says.
A stomach flu knocked out three players and an assistant coach for the San Antonio Spurs and eight players for the Washington Capitals in the past couple of weeks, according to news reports.
The disease, often characterized by doctors as "mild," is anything but that from the patient's point of view, Burgin says.
"The patient is absolutely miserable. You don't know which end to put on the pot sometimes, you get cramps, don't feel like doing anything, don't feel like taking the fluids you need."
Norovirus strikes every year, but the last time it was notably severe was the winter of 2002-03, when there were several outbreaks on cruise ships, mainly caused by a new strain known as the Farmington Hills strain, the CDC's Widdowson says. There are 30 to 40 major strains; new variations are often responsible for spikes in the number of cases. Widdowson says the CDC doesn't yet have information on strains circulating now.
Positive ID is Expensive
Unlike many bacteria and other viruses, norovirus doesn't grow in a common lab culture, so it can only be positively identified through specialized, expensive tests called PCR, which are run on stool, vomit or swab samples from the environment. Because most people recover at home with no medical care, most cases are never diagnosed.
Infection is no guarantee against future misery, he says. "You may develop immunity to one group but get whacked by another," he says, and any immunity gained is only temporary.
"In tests with volunteers, you feed them (virus), they get sick. A week later, you give it again, they're immune. You give it six months later, and they get sick again," he says.
Other studies show some people are naturally immune to norovirus. "You can throw as much virus as you want at them, and they won't get it," he says.
To cause illness, the virus binds to receptors in the gut, he says, but "clearly, there are people who don't have the receptors and won't get infected."
Then there are people who get infected and can spread the virus but don't get sick themselves.
Some research suggests people with blood type B seem to be resistant to infection and illness from at least one of the norovirus strains known as Norwalk virus, Widdowson says. Why? Another mystery.
For now, health officials are monitoring the situation and are on alert for new outbreaks, especially as students return to schools after the winter break. Happily, it is unlikely to last much longer.
"It's seasonal," Widdowson says, "and the season will end."
By Anita Manning
USA Today
(Jan. 9) - Stomach viruses tearing through communities from California to the Carolinas wrecked the December holidays for some, and they are getting the new year off to an uncomfortable start for others.
The most likely culprits, experts say, are noroviruses, the most common cause of contagious gastroenteritis, better known as the "stomach flu." Cases occur every winter, but health officials say that in recent weeks they have seen two to three times as many cases as usual.
The virus, best known as the cause of cruise ship outbreaks, is easy to catch, hard to wipe out and seems to be everywhere at once.
Last week, San Quentin State Prison closed to new prisoners and visitors after nearly 500 inmates and guards fell ill with vomiting, diarrhea, stomach cramps, headaches and low fever. Similar symptoms have been plaguing staff and residents of nursing homes in several states. College and pro athletes have missed games. Hundreds of patients have sought help in emergency rooms since mid-December. Nearly 400 people on a Caribbean cruise last month and 700 on a trans-Atlantic cruise in November were stricken, according to Associated Press reports.
Norovirus infection usually clears up after two or three days, but medical epidemiologist Marc-Alain Widdowson, a norovirus expert at the Centers for Disease Control and Prevention, says the misery of those days shouldn't be dismissed.
"When you're ill, you're really ill," he says. "People (can) vomit 20 times a day."
Norovirus can be spread through contaminated food or water, causing large outbreaks. About half of food-borne diseases are thought to be caused by norovirus, the CDC says.
But this winter, it is spreading mainly from person to person through communities, and experts believe the majority of cases are unreported.
Once it's in the house, experts say, it's tough to wipe out. It can linger for days on surfaces such as children's toys, keyboards, telephones and doorknobs, and both vomit and stool are highly infectious. It is present in the stool up to three weeks after the patient recovers, so health officials stress the importance of hand-washing, especially after using the bathroom and before preparing food.
The virus causes illness year-round, though like many, it is more common in colder months. Why it's so widespread this winter is not known, Widdowson says. "Some years, it does seem to be a lot worse than others, and this is one of those."
From Carolina to California
Among states with outbreaks:
--Texas. In Corpus Christi, there has been "a true minor epidemic here," says William Burgin Jr., health authority for the Corpus Christi-Nueces County Public Health District. "Dozens of cases at a time were reported" during the holidays, and hundreds more likely went unreported. Hospitals saw about three times as many cases as usual. "Even our emergency room folks caught it."
--North Carolina. In Asheville, 30 to 40 people have been sick enough to seek emergency room treatment for norovirus symptoms in the past two to three weeks, and up to 10 have been hospitalized, says Buncombe County Health Center medical director Steve Swearingen. And "there's no way of knowing how many are out in the community."
--California. Twenty nursing homes in Contra Costa County have reported outbreaks, twice as many as in a normal year, says communicable-disease program chief Francie Wise. "In one facility, we had over 50 patients and 21 health care workers sick," she says.
--Wisconsin. The state Division of Public Health put out an alert to local and tribal health departments last month, says spokeswoman Stephanie Marquis. "It's hitting a lot of people all at the same time." She says outbreaks in schools led a few, including two in Oshkosh, to close before the holidays.
--Montana. Cases began in nursing homes the week before Christmas, says Yellowstone City-County Health Department spokeswoman Barbara Schneeman. "That's real typical for noroviruses. It seems they like nursing homes and cruise ships."
Six facilities have confirmed positive cases. No cases were reported last winter, she says, but there was an outbreak earlier this year. From late March to early June, "we had about 1,100 to 1,200 people reporting the norovirus to us, but we estimate for every person who reports, there are two or three who don't. That would put our numbers in the 4,000 to 5,000 range."
Outbreaks in nursing homes are of special concern because of the risk of dehydration caused by vomiting and diarrhea, health experts warn. Deaths as a result of norovirus are rare. It may be a factor in roughly 300 deaths, generally in the elderly, the CDC says.
But even the young and healthy are vulnerable. About 50 University of Missouri football players, coaches, staff and family members were flattened days before Christmas while in El Paso for a bowl game.
"It spread pretty fast," says Chad Moller, team spokesman. "When you travel in a plane in closed quarters and are around each other a solid week in a hotel," it's easy to see why, he says.
A stomach flu knocked out three players and an assistant coach for the San Antonio Spurs and eight players for the Washington Capitals in the past couple of weeks, according to news reports.
The disease, often characterized by doctors as "mild," is anything but that from the patient's point of view, Burgin says.
"The patient is absolutely miserable. You don't know which end to put on the pot sometimes, you get cramps, don't feel like doing anything, don't feel like taking the fluids you need."
Norovirus strikes every year, but the last time it was notably severe was the winter of 2002-03, when there were several outbreaks on cruise ships, mainly caused by a new strain known as the Farmington Hills strain, the CDC's Widdowson says. There are 30 to 40 major strains; new variations are often responsible for spikes in the number of cases. Widdowson says the CDC doesn't yet have information on strains circulating now.
Positive ID is Expensive
Unlike many bacteria and other viruses, norovirus doesn't grow in a common lab culture, so it can only be positively identified through specialized, expensive tests called PCR, which are run on stool, vomit or swab samples from the environment. Because most people recover at home with no medical care, most cases are never diagnosed.
Infection is no guarantee against future misery, he says. "You may develop immunity to one group but get whacked by another," he says, and any immunity gained is only temporary.
"In tests with volunteers, you feed them (virus), they get sick. A week later, you give it again, they're immune. You give it six months later, and they get sick again," he says.
Other studies show some people are naturally immune to norovirus. "You can throw as much virus as you want at them, and they won't get it," he says.
To cause illness, the virus binds to receptors in the gut, he says, but "clearly, there are people who don't have the receptors and won't get infected."
Then there are people who get infected and can spread the virus but don't get sick themselves.
Some research suggests people with blood type B seem to be resistant to infection and illness from at least one of the norovirus strains known as Norwalk virus, Widdowson says. Why? Another mystery.
For now, health officials are monitoring the situation and are on alert for new outbreaks, especially as students return to schools after the winter break. Happily, it is unlikely to last much longer.
"It's seasonal," Widdowson says, "and the season will end."