Saturday, May 03, 2008

China Sounds Alert Over EV-71 Virus

 

# 1945

 

To most ears, the names are strange and mysterious. 

 

New diseases, along with old foes, are very much in the news these days - with outbreaks occurring, and being widely reported on the Internet - from all over the world. 

 

Enterovirus 71,  Coxsackievirus,  MRSA (Methicillin Resistant Staphylococcus Aureas), C. Diff (Clostridium Difficile),  Adenovirus-14, Hanta virus, Hemorrhagic Dengue Fever, Nipah Virus, Chikungunya . . .  the list goes on.   Viral and bacterial enemies that up until a few years ago, most people had never heard of.

 

If it seems that we live in a world awash in pathogens . . . well, we do. Even as old enemies, like smallpox and polio, are eradicated - nature comes up with new pathogens to throw at us, or old ones learn new tricks. 

 

Scott McPherson has done an excellent job with his series, It's Not Only Influenza That Kills, with  Part 5  dealing with new worries of a super strain of C. Diff, a bacteria that sickens a half million Americans each year, killing tens of thousands.

 

Award winning author Maryn McKenna writes on all things MRSA related on her blog Superbug, as she researches her next book which will deal with that growing concern.  

 

And the Reveres at Effect Measure often tackle emerging infectious diseases.  Today, for instance, they give a thoughtful discussion on the recent outbreaks of measles in this country, and around the world.

 

From time to time I'll cover other emerging infectious diseases besides influenza, such as my columns on the Nipah Virus and Ebola.    

 

The truth is, while not all of these emerging infectious diseases are capable of causing a pandemic, many are quite capable of causing an epidemic, and not just in third world countries.  

 

While I don't advocate that everyone worry about every outbreak of a strange or exotic disease somewhere in the world (there are, after all,  people who are paid to worry about such things), being informed is rarely a bad thing.

 

Today, we'll look at the outbreak of EV-71 in China, a virus mainly affecting children, that few people know anything about.

 

First this report (excerpts) from the Associated Press, then some discussion.

 

 

 

China's Health Ministry puts nation on alert as deadly child virus appears to spread

 

© AP

2008-05-03 12:34:05 -

 

BEIJING (AP) - China's Health Ministry issued a nationwide alert Saturday calling for heightened efforts to control a virus that has caused the deaths of 22 children in one city and shows signs of spreading.


 

Health bureaus around the country must step up monitoring for hand, foot and mouth disease following a «relatively large» outbreak

 

in the central city of Fuyang, the Health Ministry said in notices on its Web site. The ministry warned that cases were more numerous this year than in recent years and would likely peak in June and July.


The increased vigilance was prompted by a jump in cases in the Fuyang outbreak of Enterovirus 71, or EV-71, a type of hand, foot and mouth disease.

 

Up to Thursday night, 3,321 cases of EV-71 were reported in Fuyang, a fast-growing city in largely rural Anhui province. Besides the 22 deaths, 978 people remain hospitalized, 58 of them in serious or critical condition, the ministry said in a separate statement.


 

Meanwhile, state-run Xinhua News Agency reported that preliminary tests showed an 18-month-old boy who died Friday in southeastern Guangdong province was infected with EV-71, and a second suspected death is under investigation. Cases of hand, foot and mouth outbreaks, but not necessarily EV-71, have been reported in at least two other provinces.

 


Hand Foot and Mouth Disease (HFMD) is often confused by the public with Foot and Mouth Disease (FMD)  of cattle, swine, and sheep.  Despite the similar name, the diseases are in no way related.

 

HFMD is a disease, mainly of children under the age of 10, but one that can affect adults as well, caused by several non-polio enteroviruses.   The two most common causes are the Coxsackie A16 virus, and the Enterovirus-71 (EV-71).   The disease caused by the Coxsackie virus is generally less severe than that caused by the Enterovirus 71.

 

The CDC's web page on HFMD describes the illness this way:

 

It is characterized by fever, sores in the mouth, and a rash with blisters. HFMD begins with a mild fever, poor appetite, malaise ("feeling sick"), and frequently a sore throat. One or 2 days after the fever begins, painful sores develop in the mouth. They begin as small red spots that blister and then often become ulcers. They are usually located on the tongue, gums, and inside of the cheeks. The skin rash develops over 1 to 2 days with flat or raised red spots, some with blisters. The rash does not itch, and it is usually located on the palms of the hands and soles of the feet. It may also appear on the buttocks. A person with HFMD may have only the rash or the mouth ulcers.

 

This describes the common course of illness with the Coxsackie virus, where complications are rare, and victims usually recover in 7 to 10 days without hospitalization. 

 

In recent years we've seen outbreaks, particularly in the Far East, caused by the more pathogenic EV-71, and this version of the HFMD can be quite serious. Viral meningitis, and less commonly, encephalitis may occur, which sometimes proves fatal.

 

These outbreaks are spread from person to person by direct contact with nose, mouth and throat secretions, fluid from blisters, or fecal contamination from infected persons.   Hand washing, disinfecting contaminated surfaces, and avoidance of close intimate contact (kissing, hugging, sharing utensils) can reduce the spread of the virus.

 

With the deaths of 22 children over the past few weeks, some schools and day care facilities have been temporarily closed in China, and news reports tell of panicked parents sending their children out of the city to live with relatives in the country.   

 

This outbreak is expected to peak in June or July, and  comes at a bad time for Chinese authorities who are desperately trying to reassure the world that it is safe to travel to China for this summer's  Olympics.  

 

Interestingly, non-polio enteroviruses (62  have been identified: 23 Coxsackie A viruses, 6 Coxsackie B viruses, 28 echoviruses, and 5 other enteroviruses) are one of the most common infectious diseases in the world, probably only second to the common cold.

 

These viruses cause an estimated 10-15 million infections a year in the United States, generally producing mild upper respiratory infections ("summer cold") or flu-like symptoms.  They are also responsible for thousands of cases of viral, or `aseptic' meningitis each year.

 

Two major genotypes of EV-71, EV-71 B and EV-71 C, have been identified as being responsible for severe outbreaks in Australia, Japan, China, Malaysia, and Taiwan since 1997.  These two viruses are considered particularly neurovirulent, causing a high incidence of neurological complications in recent HFMD outbreaks in Asia.

 

Although not a big factor in Europe or the United States at this time, there is no reason to believe we are immune to the EV-71 version of HFMD.   

 

Given the 3 to 7 day incubation period, and the prevalence of international travel these days, it is probably just a matter of time before it shows up here.

 

A good enough reason to pay close attention to what is happening in China today.