Friday, February 26, 2010

Early Oseltamivir Therapy May Reduce Viral Shedding in 2009 H1N1 Virus Infection

During the pandemic containment response in Singapore, all patients with positive polymerase chain reaction (PCR) results for pandemic influenza (H1N1) 2009 were hospitalized, given oseltamivir for 5 days, and discharged when daily PCR results for combined nasal and throat swab samples became negative.


Prolonged viral shedding was noted in young immunocompetent adults with mild pandemic influenza (H1N1) 2009 despite receipt of oseltamivir. When prescribed during the first 3 days of illness, oseltamivir shortened the duration of viral shedding.


Source: Clinical Infectious Diseases http://www.journals.uchicago.edu/doi/abs/10.1086/651083

WHO Sticks With Current Pandemic Phase

The WHO emergency committee of experts, set up under International Health Regulations (IHR), met in a 2-hour teleconference on Tuesday, and discussed whether to move from pandemic alert phase 6 (pandemic phase) to a post-peak phase.

The committee has recommended holding at the current pandemic alert level based on evidence of new community spread of the virus in West Africa, and the possibility of a second wave of illnesses as the Southern Hemisphere enters its winter months.

The committee expressed that it is clear that the pandemic situation varies in different parts of the world. Though flu activity continues to taper off in many Northern Hemisphere countries, the virus is still active in areas such as Eastern Europe and central Asia, and there are increased reports of new pandemic activity in the West African countries Senegal and Mauritania.

Though many countries in the Northern Hemisphere have had two pandemic flu waves, many Southern Hemisphere nations have had only one, and those countries are just entering their winter months, when increased influenza activity is anticipated.

Members of the emergency committee were concerned that transitioning to a post-peak pandemic phase could undermine control actions in some countries, he said, adding that the group said it would revisit the issue over the next several weeks when more epidemiological evidence is available.

Dr Margaret Chan, the WHO's director-general, asked the committee to review three specific IHR recommendations, according to a statement today from the WHO. The committee favored continuing the recommendations, but urged an update to the second recommendation, replacing "intensify" with "maintain" regarding surveillance. The recommendations thus now read:

  • Countries should not close borders or restrict international traffic and trade.
  • Maintain surveillance of unusual flu-like illness and severe pneumonia.
  • If ill, it is prudent to delay travel.

The WHO continues to endorse vaccination, especially because the pandemic H1N1 virus continues to dominate seasonal strains. The vaccine has excellent safety and efficacy profiles, and the WHO estimates that about 300 million people across the globe have been immunized.

Source: CIDRAP http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/feb2410pandemic.html

The CDC Behavioral Risk Factor Surveillance System

The Behavioral Risk Factor Surveillance System (BRFSS) is used in the United States as a state-based system of health surveys that collects information on health risk behaviors, preventive health practices, and health care access primarily related to chronic disease and injury.

The timely data on health related behaviors obtained by BRFSS is used by states to identify and track health objectives, and develop and evaluate public health policies and programs.

The 2009 H1N1 ILI module is able to indicate how much ILI is reported in the participating states and territories. When participants report that they have had ILI, they are asked follow-up questions, including whether they sought medical care for their illness. Participants are also asked whether anyone in their households were hospitalized for ILI. These data are supplemental to CDC’s weekly FluView surveillance system and provide additional information about ILI, and also about behaviors related to influenza.

Country offices can learn more about the BRFSS at http://www.cdc.gov/brfss and possibly develop context specific questionnaires of their own.

Thursday, February 18, 2010

WHO Recommendations for 2010-2011 Influenza Vaccine Viruses

As mentioned in last week's blog entry, twice a year, WHO influenza experts meet to make recommendations on the composition of the next season's influenza vaccines, and this meeting for the upcoming influenza season was held last week. These recommendations provide a guide to national public health authorities and vaccine manufacturers on the viruses to be included in influenza vaccines for the next northern hemisphere season.

WHO recommends that for the 2010-2011 influenza season, the following viruses be included in influenza vaccines:
  • An A/California/7/2009 (H1N1)-like virus
  • An A/Perth/16/2009 (H3N2)-like virus
  • A B/Brisbane/60/2008-like virus
Usually, influenza vaccines for seasonal vaccines contain three different viruses (i.e., are trivalent) -- including A (H1N1), A (H3N2) and B viruses that are considered representative of those that are in circulation. In 2009, because of the H1N1 influenza pandemic, many vaccine manufacturers worldwide have also produced monovalent pandemic vaccines which contain only A/California/7/2009 (H1N1). The decisions on whether to make trivalent and monovalent vaccines containing these viruses will be made by national and regional authorities.

Trivalent vaccines that contain all three of the WHO recommended viruses are expected to protect against both pandemic and seasonal influenza.

Source: WHO http://www.who.int/csr/disease/influenza/201002_RecommendationFAQ.pdf

Egypt Reports Further H5N1 Human and Poultry Infections

Egypt's health ministry has reported another human H5N1 influenza case, in a 29-year-old woman from Menofia governorate who died of her infection, according to a statement yesterday from the Egyptian State Information Service.

News of the latest human case came as Egypt's animal health officials detailed 33 new H5N1 outbreaks in poultry that have been confirmed since Feb 1 and as foreign-language media sources reported other human H5N1 infections and deaths.

The notice of the woman's infection contained few details, but said her death brought the number of fatalities to 30 and raised the number of cases to as many as 99. When the World Health Organization (WHO) reported the latest Egyptian case on Feb 10, it listed Egypt's total as 97 cases and 27 fatalities, so it's unclear if Egypt's tally includes H5N1 cases and deaths that haven't yet been reported to WHO. The FluTrackers infectious disease message board has noted what appear to be additional H5N1 deaths and an illness that have only been reported in the Arabic press so far.

Since the first of the year Egypt has reported seven H5N1 infections in humans, and the infections seem to be striking adults more than children, a change from a pattern in 2009, when the youngest children seemed to bear the greatest disease burden. Among seven H5N1 infections reported to the WHO this year, five have occurred in adults—three women and two men.

Meanwhile, the rise in human H5N1 infections seems to be following increased H5N1 activity in the country's s poultry. Egypt's Strengthening Avian Influenza Detection and Response (SAIDR) site recently posted reports of 33 H5N1 detections since Feb 1. The outbreaks hit birds in 12 different governorates, with the highest numbers of outbreaks in Dakahlia (7), Qalyubia (6), and Menofia (5).

Most of the outbreaks were detected in household birds, though the virus was detected at four farms—two during routine surveillance. The type of operation was not reported for one of the outbreaks.

Source: CIDRAP http://www.cidrap.umn.edu/cidrap/content/influenza/panflu/news/feb1510avian-br.html

Friday, February 12, 2010

WHO - consultation on 2010 influenza vaccine

Twice a year, influenza experts meet to make recommendations on the composition of the next season's influenza vaccines. Next week, the group will determine which viruses they recommend be put in influenza vaccines for use in the northern hemisphere in 2010.

These consultations are held twice annually, one for the northern hemisphere (usually in February) and the other for the southern hemisphere (usually in September). The consultations are conducted to finalize analyses of influenza viruses that have been shared with WHO through a global network of national laboratories called GISN (Global Influenza Surveillance Network) and to make recommendations to WHO of which influenza viruses should be contained in influenza vaccine for the upcoming season. The analyses of viruses are complemented by available epidemiological and clinical information. These meetings will cover influenza viruses considered infectious for people and for which either developmental or commercial vaccines have been made. Such viruses include pandemic A(H1N1), seasonal influenza viruses, influenza A (H5N1) and influenza A(H9N2) viruses. These meetings also discuss serology studies of whether antibodies to current vaccines cover circulating viruses, and the availability of vaccine reassortant viruses and reference reagents. Based on all relevant considerations, the consultation provides a recommendation to WHO for composition of influenza vaccines.

In contrast to many other vaccines, the viruses in influenza vaccines are replaced frequently because circulating influenza viruses often mutate and change. Keeping up with these changes requires global virus sharing and monitoring.

Visit WHO's brief to learn more: http://www.who.int/entity/csr/disease/influenza/qanda_vaccinerechow.pdf

Monday, February 8, 2010

Global Tamiflu-resistant H1N1 cases reach 225

From CIDRAP News -- February 5, 2010

The World Health Organization (WHO) reported today that 225 cases of H1N1 flu with resistance to oseltamivir (Tamiflu) have been found worldwide, and resistant viruses have spread from person to person in several clusters but have not spilled into the community.

Many of the resistant cases involved people with severely weakened immunity, reinforcing the importance of monitoring for the problem in such patients, the WHO said in today's issue of its Weekly Epidemiological Record.

The 225 cases come from 20 countries and include 65 cases in the Americas, 77 in Europe, 1 in Africa, and 82 in the Western Pacific region, the agency said. All the isolates had the H275Y mutation that confers resistance to oseltamivir but not to the other neuraminidase inhibitor in general use, zanamivir (Relenza).

Of 142 cases for which data were available, 56 (40%) were in severely immunocompromised patients, and 54 (38%) were linked to treatment of flu. Another 16 cases (11%) were associated with preventive treatment, and 16 others did not involve any known antiviral use.

The WHO reviewed reports of three clusters of resistant cases, one each in the United States, the United Kingdom, and Vietnam. They involved:

  • Four severely immunocompromised patients in the same ward at Duke University Hospital in Durham, N.C., in October and November; in three cases, resistance was found before the drug was used
  • Eight patients with hematological malignancies at the University Hospital of Wales in Cardiff, Wales, in November, at least four of whom contracted the resistant virus from someone else
  • Seven healthy young adults in Vietnam who traveled together by train last July and were believed to have caught the virus from an unidentified index case; the cluster apparently did not lead to any further cases

The WHO said the number of resistant cases remains low despite the large scale of the pandemic, the wide use of oseltamivir, and extensive monitoring.

"Although there is no evidence of general community circulation of such resistant viruses, there is clear evidence of limited person-to-person transmission in several epidemiological settings," the agency said. It added that active surveillance for resistant cases should continue and all cases should be investigated and reported to health authorities.

Source:

CIDRAP http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/feb0510resist-jw.html

WHO http://www.who.int/wer/2010/wer8506.pdf

2009 H1N1 Outbreak in Northern Vietnam

On February 4th, Vietnamese health officials reported an outbreak of 2009 H1N1 in the northern province of Bac Kan.

Eighteen people have recently contracted the A/H1N1 virus in the province’s Na Ri District, said Dr. Nguyen Huy Nga of the Preventive Health and Environment Department. The patients have shown typical symptoms of the virus including fever, cough, sore throat, and muscle pain, he added.

Dr. Nga made the announcement at a meeting of the National Steering Board for Human Flu Prevention on February 3 in Hanoi.

Earlier on January 27, the Ministry of Health reported that several Bac Kan students at a secondary school in Dong Xa Commune had contracted the illness.

Dr. Nga said the epidemic is complicated and that the health ministry has therefore ordered medical clinics to strengthen monitoring of A/H1N1 cases, quarantine patients immediately, and ensure prompt treatment of those affected to stop the virus from spreading. Hospitals have also been asked to step up monitoring of avian flu, acute diarrhea and dengue fever.

Provinces with border crossings must control the flow of visitors from affected regions and detect swine flu cases quickly.

Source: http://www.english.vietnamnet.vn/Health/201002/Fresh-swine-flu-outbreak-hits-Bac-Kan-893274/

Neurologic Manifestations of Pandemic (H1N1) 2009 Virus Infection

A recently published article in the scientific journal Emerging Infectious Diseases highlighted a case study of a 34 year old male in Thailand who developed neurologic manifestations - namely, progressive quadriplegia - after contracting 2009 H1N1.

Similar to the effects of other viruses, pandemic (H1N1) 2009 virus may cause neurologic complications. Associated neurologic symptoms were first reported from Dallas, Texas, USA: 4 children experienced unexplained seizures or had an alteration of consciousness level that was associated with this virus.


Source: CDC EID http://www.cdc.gov/eid/content/16/3/pdfs/09-1699.pdf

Monday, February 1, 2010

Avian Influenza in Humans: Lessons from Egypt

From Eurosurveillance -- January 28, 2010

Highly pathogenic avian influenza A(H5N1) has ravaged the Egyptian poultry population. Ninety human cases, including 27 fatalities have been recorded by 30 December, 2009. However, epidemiological information on the infection in humans in Egypt is scarce. We analyzed the first three years of highly pathogenic avian influenza A(H5N1) in Egypt between 20 March 2006 and 31 August 2009 and found that more cases occurred in females than males, especially in 2006 and 2007.

Women in the age group 20-39 years had the greatest tendency to be infected. It took an average of one day and 18 hours to seek medical assistance in patients who recovered and of six days in fatal cases. Children sought treatment much earlier than adults. On average, patients died 11 days after the onset of symptoms. Exposure to infected poultry remained the most important risk factor.

The overall case fatality in this study was 32% (27/85). This percentage may appear small when compared with statistics from other places, for example 82% in Indonesia (115/141), 68% in Thailand (17/25), 66% in China (25/38) and 50% in Vietnam (56/111). Nevertheless, with the exceptional surge in number of cases (especially in children) arising in Egypt in 2009 and the recent recurrence of human cases of avian influenza A(H5N1) in China and Vietnam despite an intensive control program in the poultry populations, the pandemic potential of this virus is still very evident.

Public health guidelines in Egypt will need to be tailored to meet the local situation, taking into consideration the agricultural practices and the people’s perceptions. It will also be necessary to conduct more studies on human H5N1 influenza infection in Africa to evaluate the situation of asymptomatic carriers and unreported cases.