WHO findings on bird flu treatment

on Friday the World Health Organization (WHO) reported the early conclusions of a group of international experts who met last month to compare evidence on treatments, including attempts by some doctors to use steroids in addition to other treatment measures.

The experts conclude that Bird flu patients given early treatment with the antiviral drug Tamiflu have the best chance of surviving but that using steroids can do more harm than good, .

"Corticosteroid therapy has failed so far to show effectiveness," the WHO warned in a statement. "Prolonged or high dose corticosteroids can result in serious adverse events."

Frederick Hayden of WHO's global influenza program said some doctors in Vietnam and Indonesia, had used steroids to try to save quickly deteriorating bird flu patients. Published research showed eight of nine had died.

"A concern is some treatment is of unsubstantiated value and in some instances may be doing more harm than good," he told Reuters.

The WHO confirmed that early treatment with Tamiflu (known generically as oseltamivir reduces mortaality from the H5N1 virus. Giving it to people with advanced symptoms was also "warranted".

"Data presented gave strong support that early treatment makes a difference," Hayden said, citing data from Egypt where 20 of 34 bird flu patients have survived to date.

"Unfortunately the problem is many patients are coming in late with shortness of breath and progressive symptoms that would indicate advanced viral pneumonia," he said.

Tamiflu can also be used at a two-fold higher dosage and possibly in so-called "dual antiviral therapy" with an older class of drugs known as amantadine, the WHO said, in line with previous recommendations.

But such decisions should be made on a case-by-case basis, especially in patients with pneumonia or progressive disease.

Combining Tamiflu with amantadine may be especially useful in countries where the virus is susceptible to amantadine.

These countries include China and parts of Europe and Africa where a particular H5N1 subvirus or "clade" has spread, causing human cases since January 2006, according to Hayden. He cited Turkey, Egypt and Azerbaijan.

Antibiotics should not be given preventively, due to possible resistance and side-effects but according to the WHO should only be given if there is good reason to suspect the patient has a bacterial complication to pneumonia.

Caterpillars produce flu vaccine

Flu vaccine is normally made using chicken eggs but now for the first time research has shown that genetically engineered flu vaccine can be made from yellow striped caterpillars according to a University of Rochester study.

Early results suggest that this caterpillar method could be a faster, easier alternative to traditional egg-based production. If this proves to be the case when scaled up then this might provide a quicker vaccine development cycle in response to a pandemic.

The research was funded by the vaccine's maker, Protein Sciences Corp. The company designed the study with Dr. John Treanor, director of UR's Vaccine Treatment and Evaluation Unit and lead author of the study. Dr.Treanor, is also professor of medicine and of microbiology and immunology at UR.

The results are reported in the Journal of the American Medical Association.

The experimental vaccine used in the research was designed to protect against three of the common influenza strains. Among participants who got single high-dose injections, none developed the flu and at least two-thirds had a strong immune response.

More than half of those given a lower dose had a strong immune response, and two got flu.

In a control seven patients who received a dummy vaccine got the flu.

451 adults took part in the study during the 2004-05 flu season.

Current production methods takes about nine months to produce vaccine supplies and rely on hens laying millions of eggs. Live flu viruses are injected into the eggs and multiply, then the shells are broken and the viruses inactivated and treated to create vaccine.

The experimental method uses fall army worms — abundant caterpillars that are vulnerable to a caterpillar virus. The researchers replaced a gene from that virus with a flu virus gene, then injected it into the worms to make more flu viruses. The process took about a month less than the egg method and didn't involve using live flu viruses.

The study is likely to boost interest in insect production methods as an alternative to traditional egg based methods for producing flu vaccine.

Flu Transmission via hands and surfaces

While most people are aware that colds and flu are transmitted from person to person via coughing and sneezing there is less awareness that people can catch flu and colds through other forms of direct and indirect contact.

One of the pre-requisites in preparing the public for any pending pandemic will be to greatly increase public awareness of these forms of transmission and effective measures for controlling them.

Influenza is of course highly contagious, in particular for those who don't have any pre-existing antibodies against influenza obtained through previous viral exposure. This will typically include young children during inter-pandemic phase influenza and almost everyone during a highly mutated viral pandemic.

Commonly around 50% of all "normal" influenza infections are asymptomatic and this is particularly common in children. Most influenza virus is transmitted via droplets through the coughing and sneezing of infected persons. It can however also be transmitted by direct and indirect contact and many people seem unaware of this.

Direct-contact transmission involves skin-to-skin contact and the physical transfer of the virus to a susceptible person from an infected person.

Such direct contact transmission can occur in a hospital or care setting for example as staff perform patient care activities involving physical contact. Direct-contact transmission in these settings can also occur between two patients (e.g., by hand contact). In domestic settings when people fall ill, awareness of contact transmission will be less and the risks of this route may be higher.

Indirect-contact transmission involves a contaminated intermediate object, usually inanimate, in the infected persons environment. There is some evidence that flu virus can survive outside the human body for some time. The infected persons may contaminate a surface through coughing , sneezing or hand contact ( if hands have come into contact with mouth or nose). Another person touching this surface with their hands may then transfer this infection to themselves through hand to face contact. (There have been suggestions that influenza can even infect through the eye membranes).

There is insufficient data to exactly determine the proportion of influenza transmission that is attributable to direct or indirect contact.

So apart from being actually coughed or sneezed upon by an infected person, the most common way to catch the flu is by touching something which has been coughed on or sneezed upon by an infected person. The person who used that door handle before you had the flu. They covered their mouth with their hand as they coughed then used that same hand to open the door. You touch the same place and without thinking later rub your eye or nose. You have introduced the virus to your most vulnerable point of infection.

Good hand washing practice and awareness of such transmission routes is vital.
Droplet transmission is still thought the predominant overall form of spread particularly in a setting such as a crowded space where air exchange is limited. However contact transmission should always be controlled for.

Good hand washing practice should involve the use of reliable soaps and/or wipes.

Type B flu virus resistance to Tamiflu and Relenza

Japan has been known for prescribing antiviral flu drugs more frequently than other countries and now one of the less common strains of flu has shown hints of resistance to Tamiflu and Relenza among patients in a small study of patients who had type B influenza.

Type B is normally milder and causes smaller outbreaks than the more common type A.

The findings indicate that doctors may eventually need new medications to treat drug-resistant flu if the viruses become more prevalent.

Previous studies, including work by the same researchers, have found a few cases of resistance to Tamiflu in type A flu, the variety thought most likely to cause a pandemic if bird flu mutates into a human transmissable form.

Dr. William Schaffner, an infectious-disease specialist at Vanderbilt University who was not involved in the study, said Japanese doctors prescribe anti-flu drugs perhaps too often, giving viruses a chance to evolve.

''We were afraid this might happen.'' Schaffner said.

Tamiflu and Relenza, designed to treat seasonal flu, are thought likely to be helpful in treating a global epidemic but this finding confims the importance of vaccination and other preventive measures.

The U.S. government has stockpiled Tamiflu and Relenza, and has funded new anti-flu drug development.

Evolving resistance among viruses is of course biologically inevtiable when doctors use anti-viral drug widely which is why the continual development of new drugs is vital.

The study appeared in Wednesday's Journal of the American Medical Association. Samples from 74 children before and after they were treated with Tamiflu showed drug-resistant virus in one of the children after treatment, indicating the resistance had emerged during treatment.

Samples from 422 untreated children and adults with flu showed drug-resistant virus in seven patients.

The rate of resistance to this family of drugs, less than 2 percent, was lower than for type A influenza where drug-resistant type A virus has been reported at 18 percent.

Note that the study had financial support from the Japanese and U.S. governments. Some researchers reported receiving speaking fees or previous grant support from drug companies, including a company developing a new anti-flu drug.

Bird Flu Round Up 5th April 2007

The Gulf Times reports that bird flu has spread to a new poultry farm in Bangladesh despite the efforts by vets and health workers.
An official of the Fisheries and Livestock ministry reported that “The latest farm confirmed to have H5N1 virus is in northern Jamalpur 200km (125 miles) from the capital Dhaka,” .

Since bird flu was detected in six farms at Savar near the capital in March 72,000 chickens have been culled from 26 farms and 500 workers at infected farms given a local version of the Tamiflu anti-viral drug.

About 4m Bangladeshis are directly or indirectly associated with poultry farming.

The Arab Times online reports that on Wednesday Kuwait sent samples from Bangladeshi bird handlers to WHO laboratory in Cairo for confirmation of test results conducted in Kuwait - according to Dr Ahmad Al-Shatti, spokesman for the Health Ministry. Test results are expected Thursday. The four workers had earlier shown bird-flu symptoms.

Dr Al-Shatti said the bird flu situation in the Kuwait was under control, : “The bird handlers are in good health and there is no cause for concern. We have plans in place to deal with any emergent situation."
Since Kuwait reported a bird flu outbreak late February authorities have slaughtered around 1.6 million birds. The four Bangladeshi bird handlers were part of the task force slaughtering birds in Wafra area, where most positive cases were discovered.

In the US, at a farm in West Virginia test results from turkeys have indicated exposure to H5N2 virus according to World of Poultry.
The test samples were part of routine, pre-slaughter surveillance and the turkeys showed no signs of illness and no mortality.
USDA Chief Veterinarian John Clifford stressed, "Every indication is that the virus is consistent with low pathogenic strains of avian influenza, or LPAI, which are commonly found in birds and typically cause only minor sickness or no noticeable symptoms. We can say for certain this is not the highly pathogenic H5N1 strain." The National Veterinary Services Laboratory plans to run sequencing and pathogenicity tests to further identify the virus.

Around 25,000 turkeys were slaughtered and poultry operations within a 6-mile radius of the affected farm closely monitored.